2,675 research outputs found

    Using ontologies for modeling context-aware services platforms

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    This paper discusses the suitability of using ontologies for modeling context-aware services platforms. It addresses the directions of research we are following in the WASP (Web Architectures for Services Platforms) project. For this purpose a simple scenario is considered

    The tropospheric gas composition of Jupiter's north equatorial belt (NH3, PH3, CH3D, GeH4, H2O) and the Jovian D/H isotropic ratio

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    The gas composition of the troposphere of Jupiter in the clearest regions of the North Equatorial Belt (NEB) was derived from the Voyager 1 IRIS data. The infrared spectrum for this homogeneous cloud free region was modeled to infer altitude profiles for NH3, PH3, GeH4 and H2O. The Profiles for NH3 and PH3 were found to be depleted in the upper troposphere but otherwise in agreement with their solar values at the 1 bar level. The mole fraction for CH3D was determined to be 3.5(+1.0 or -1.3) x 10 to the minus 7th power. The GeH4 mole fraction of 7+ or -2 x 10 to the minus 10th power at the 2 to 3 bar level is a factor of 10 lower than the solar value. The H2O mole fraction is approximately 1 x 0.00001 at the 2.5 bar level and is increasing to approximately 3 x 0.00001 at 4 bars where it is a factor of 30 lower than solar. Using IRIS infrared values for the mole fractions of CH3D and CH4 a value of D/H = 3.6(+1.0 or -1.4)x 0.00001 is derived. Assuming this Jovian D/H ratio is representative of the protosolar nebula, and correcting for chemical galactic evolution, yields a value of 5.5 - 9.0 x 0.00001 for the primordial D/H ratio and an upper limit of 1.8 to 2.4 x 10 to the minus 31st power cu cm for the present day baryon density

    Kerjasama UNODC – Indonesia Dalam Memerangi Perdagangan Manusia Periode 2007-2013

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    The impact of technological advancement does not always has apositive effect. For example, one of the negative impact is the growingforms of transnational crime such as human trafficking. As onecontinent from five continents in the world, Asia is the region with thenumber of victims of human trafficking at most. Indonesia is one ofAsian countries which has become a source, destination, and transit ofhuman trafficking. Surely the Government of Indonesia continues tostrive to combat human trafficking in various ways, one of them ispartnership with UNODC. This thesis aims to determine the form ofthe partnership between the Government of Indonesia with theUNODC in combating human trafficking with period 2007-2013. Inthis thesis, author use the theory of Liberalism Institutionalism,because it is considered the most appropriate theory to explain thecooperation between the Government of Indonesia and UNODC. Inthis thesis, author use descriptive-explanative research type to explainand to describe the phenomenon of human trafficking in Indonesia.The results from this research is that the cooperation between theGovernment of Indonesia and UNODC are effective and inaccordance with the needs of the Government of Indonesia especiallyon the aspect of capacity building of Indonesian law enforcementofficial. However, the result from this cooperation does not give apositive implication for the reduction of the number of victims ofhuman trafficking in Indonesia

    Contact binaries with additional components. III. The adaptive optics detections

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    We present results of the CFHT adaptive optics search for companions of a homogeneous group of contact binary stars, as a contribution to our attempts to prove a hypothesis that these binaries require a third star to become so close as observed. In addition to companions directly discovered at separations of >=1", we introduced a new method of AO image analysis utilizing distortions of the AO diffraction ring pattern at separations of 0.07"-1". Very close companions, with separations in the latter range were discovered in systems HV Aqr, OO Aql, CK Boo, XY Leo, BE Scl, and RZ Tau. More distant companions were detected in V402 Aur, AO Cam, V2082 Cyg. Our results provide a contribution to the mounting evidence that the presence of close companions is a very common phenomenon for very close binaries with orbital periods <1 day.Comment: Full Figs.4 and 5 are in http://www.astro.utoronto.ca/~rucinski/Triples3

    How to tell if your cloud files are vulnerable to drive crashes

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    This paper presents a new challenge--verifying that a remote server is storing a file in a fault-tolerant manner, i.e., such that it can survive hard-drive failures. We describe an approach called the Remote Assessment of Fault Tolerance (RAFT). The key technique in a RAFT is to measure the time taken for a server to respond to a read request for a collection of file blocks. The larger the number of hard drives across which a file is distributed, the faster the read-request response. Erasure codes also play an important role in our solution. We describe a theoretical framework for RAFTs and offer experimental evidence that RAFTs can work in practice in several settings of interest

    Towards a norm-driven design of context-aware e-health applications

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    In this paper, we explore the usefulness of elaborating process models with norms, especially focusing on the Norm Analysis Method (NAM) as an elaboration tool that can be combined with a process modeling tool, such as Petri Net (PN). The PN-NAM combination has been particularly considered in the paper in relation to a challenge that concerns the design of context-aware applications, namely the challenge of specifying and elaborating complex behaviors that may include alternative (context-driven) processes (we assume that a user context space can be defined and that each context state within this space corresponds to an alternative application service behavior). Hence, the main contribution of our paper comprises an adaptability-driven methodological and modeling support to the design of context-aware applications; modeling guidelines are proposed, considered together with corresponding modeling tools (in particular PN and NAM), and partially illustrated by means of an e-Health-related example. Given the multi-disciplinary nature of the e-Health domain, it is expected that the current research will be useful for it. In particular, e-Health system developers might benefit from the relevant methodological and modeling support, proposed in the paper

    The X-ray Position and Optical Counterpart of the Accretion-Powered Millisecond Pulsar XTE J1814-338

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    We report the precise optical and X-ray localization of the 3.2 ms accretion-powered X-ray pulsar XTE J1814-338 with data from the Chandra X-Ray Observatory as well as optical observations conducted during the 2003 June discovery outburst. Optical imaging of the field during the outburst of this soft X-ray transient reveals an R = 18 star at the X-ray position. This star is absent (R > 20) from an archival 1989 image of the field and brightened during the 2003 outburst, and we therefore identify it as the optical counterpart of XTE J1814-338. The best source position derived from optical astrometry is R.A. = 18h13m39.s04, Dec.= -33d46m22.3s (J2000). The featureless X-ray spectrum of the pulsar in outburst is best fit by an absorbed power-law (with photon index = 1.41 +- 0.06) plus blackbody (with kT = 0.95 +- 0.13 keV) model, where the blackbody component contributes approximately 10% of the source flux. The optical broad-band spectrum shows evidence for an excess of infrared emission with respect to an X-ray heated accretion disk model, suggesting a significant contribution from the secondary or from a synchrotron-emitting region. A follow-up observation performed when XTE J1814-338 was in quiescence reveals no counterpart to a limiting magnitude of R = 23.3. This suggests that the secondary is an M3 V or later-type star, and therefore very unlikely to be responsible for the soft excess, making synchroton emission a more reasonable candidate.Comment: Accepted for publication in ApJ. 6 pages; 3 figure

    Spatially resolved spectroscopy of planetary nebulae and their halos I. Five galactic disk objects

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    Strong mass loss off stars at the tip of the asymptotic giant branch (AGB) profoundly affects properties of these stars and their surroundings, including the subsequent planetary nebula (PN) stage. With this study we wanted to determine physical properties of mass loss by studying weakly emitting halos, focusing on objects in the galactic disk. Halos surround the, up to several thousand times, brighter central regions of PNe. Young halos, specifically, still contain information of the preceeding final mass loss stage on the AGB. In the observations we used the method of integral field spectroscopy with the PMAS instrument. This is the first committed study of halos of PNe that uses this technique. We improved our data analysis by a number of steps. In a study of the influence of scattered light we found that a moderate fraction of intensities in the inner halo originate in adjacent regions. As we combine line intensities of distant wavelengths, and because radial intensity gradients are steep, we corrected for effects of differential atmospheric refraction. In order to increase the signal-to-noise of weak emission lines we introduced a dedicated method to bin spectra of individual spatial elements. We also developed a general technique to subtract telluric lines - without using separate sky exposures. By these steps we avoided introducing errors of several thousand Kelvin to our temperature measurements in the halo. For IC3568 we detected a halo. For M2-2 we found a halo radius that is 2.5 times larger... (abridged)Comment: 27 pages, 29 figures, A&A (in press), Abridged abstract, Corrected and clarified various minor issues; the section on scattered light is significantly clarifie
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