45,141 research outputs found
A K band survey in the Groth Strip Flanking Fields
No full text© 2003. Instituto de Astronomía, UNAM. Meeting on Science with the GTC (1st. 2002. Granada/Spain). Financial support for this research has been provided by the Spanish Programa Nacional de Astronomía y Astrofísica under grants AYA2000-977 and AYA2000-1790.As a part of our collaboration in the COSMOS Project, devoted to the characterization of galaxies during the ep o c h of maximum star formation in the history of the Universe, we have carried out a deep photometric survey covering about 380 arcmin^(2) in the so-called Groth Strip Flanking Fields. The observations were obtained in the K´ band with the OMEGA-PRIME infrared camera at the 3.5 m telescope at the Hispano–German Calar Alto Observatory . Galaxy counts and photometric redshifts will be computed in order to prepare future observations with EMIR.Como parte de nuestra colaboración en el Proyecto COSMOS, dedicado a la caracterización de galaxias pertenecientes a la época de máxima formación estelar del Universo, hemos realizado una exploración fotométrica profunda con un área aproximada de 380 arcmin^(2) de la zona adyacente al llamado Campo de Groth. Las observaciones se han obtenido en la banda K´ con la cámara infrarroja OMEGA-PRIME del telescopio de 3.5 m del Observatorio Hispano–Alemán de Calar Alto. Se pretende realizar conteos de galaxias y calcular desplazamientos al rojo fotométricos para la preparación de futuras observaciones con EMIR.Programa Nacional de Astronomía y AstrofísicaDepto. de Física de la Tierra y AstrofísicaFac. de Ciencias FísicasTRUEpu
The Origin of Data: Enabling the Determination of Provenance in Multi-institutional Scientific Systems through the Documentation of Processes
No full textThe Oxford English Dictionary defines provenance as (i) the fact of coming from some particular source or quarter; origin, derivation. (ii) the history or pedigree of a work of art, manuscript, rare book, etc.; concr., a record of the ultimate derivation and passage of an item through its various owners. In art, knowing the provenance of an artwork lends weight and authority to it while providing a context for curators and the public to understand and appreciate the work’s value. Without such a documented history, the work may be misunderstood, unappreciated, or undervalued. In computer systems, knowing the provenance of digital objects would provide them with greater weight, authority, and context just as it does for works of art. Specifically, if the provenance of digital objects could be determined, then users could understand how documents were produced, how simulation results were generated, and why decisions were made. Provenance is of particular importance in science, where experimental results are reused, reproduced, and verified. However, science is increasingly being done through large-scale collaborations that span multiple institutions, which makes the problem of determining the provenance of scientific results significantly harder. Current approaches to this problem are not designed specifically for multi-institutional scientific systems and their evolution towards greater dynamic and peer-to-peer topologies. Therefore, this thesis advocates a new approach, namely, that through the autonomous creation, scalable recording, and principled organisation of documentation of systems’ processes, the determination of the provenance of results produced by complex multi-institutional scientific systems is enabled. The dissertation makes four contributions to the state of the art. First is the idea that provenance is a query performed over documentation of a system’s past process. Thus, the problem is one of how to collect and collate documentation from multiple distributed sources and organise it in a manner that enables the provenance of a digital object to be determined. Second is an open, generic, shared, principled data model for documentation of processes, which enables its collation so that it provides high-quality evidence that a system’s processes occurred. Once documentation has been created, it is recorded into specialised repositories called provenance stores using a formally specified protocol, which ensures documentation has high-quality characteristics. Furthermore, patterns and techniques are given to permit the distributed deployment of provenance stores. The protocol and patterns are the third contribution. The fourth contribution is a characterisation of the use of documentation of process to answer questions related to the provenance of digital objects and the impact recording has on application performance. Specifically, in the context of a bioinformatics case study, it is shown that six different provenance use cases are answered given an overhead of 13% on experiment run-time. Beyond the case study, the solution has been applied to other applications including fault tolerance in service-oriented systems, aerospace engineering, and organ transplant management
Jean-Antoine de Baïfs Psaulher. Metrische Bearbeitung der Psalmen mit Einleitung , Anmerkungen und einem Wœrterverzeichnis , zum ersten mal hgg. von Dr Ernst-Joh. Groth, 1888. (vol. IX de la Sammlung französischer neudrucke, publiée sous la direction de M. K. Volmœller)
No full textM. P. Jean-Antoine de Baïfs Psaulher. Metrische Bearbeitung der Psalmen mit Einleitung , Anmerkungen und einem Wœrterverzeichnis , zum ersten mal hgg. von Dr Ernst-Joh. Groth, 1888. (vol. IX de la Sammlung französischer neudrucke, publiée sous la direction de M. K. Volmœller). In: Romania, tome 18 n°71, 1889. pp. 514-515
Compatibility test and adapter generation for interfaces of software components
No full textCompatibility test and adapter generation for interfaces of software components / J. M. Zaha, M. Geisenberger, M. Groth. - In: Distributed computing and internet technology : first International Conference, ICDCIT 2004 Bhubaneswar, India, December 22 - 24, 2004 / R. K. Ghosh ... (eds.). - Berlin u.a. : Springer, 2004. - S. 318-328. - (Lecture notes in computer science ; 3347
K-s number counts in the Groth and Coppi fields
No full text© 2003. The American Astronomical Society. We thank the referee, Jonathan Gardner, for his comments, which helped improve the manuscript. We acknowledge useful discussions on number counts with Matthew Bershady, David Koo, and James Lowenthal. James Lowenthal, Peter Hammersley, and José Acosta-Pulido gave us invaluable help and insights on NIR image reduction. This research has made use of the HST archive and the MDS online database. The Medium Deep Survey catalog is based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. The MDS analysis was funded by the HST WFPC2 Team and STScI grants GO2684, GO6951, GO7536, and GO8384 to Richard Griffiths and Kavan Ratnatunga at Carnegie Mellon University.We have used William Herschel Telescope/INGRID K_(s) images on two high-latitude fields, the Coppi and Groth strips, to obtain galaxy number counts over ~ 180 arcmin^(2), to a depth of K_(s) ~ 21:0. Detection efficiency corrections as a function of object size have been calculated on each pointing. We have used a signalto-noise threshold in two complementary half-exposure images to remove spurious detections. Our data cover the range from K_(s) = 14.5 to K_(s) = 21.0, so they are useful for investigating a previously reported change in the number count slope (d log N/dm) at K ~ 17. We find a slope ϒ_(b)= 0:54- 0:63 for K 17.5. A total contribution from galaxies to the extragalactic background light (EBL) in the K band of νI_(ν)=10.5 nW m^(-2) sr^(-1) has been calculated. This K-band EBL coming from galaxies accounts for only ~50% of the recent measurements of the diffuse EBL. Standard number count models fail to reproduce the observed slope change at K ~ 17.5 unless elliptical and spiral formation is pushed to z<̱̱̰2.Space Telescope Science InstituteHST WFPC2 TeamSTScIDepto. de Física de la Tierra y AstrofísicaFac. de Ciencias FísicasTRUEpu
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
A model of process documentation to determine provenance in mash-ups
No full textThrough technologies such as RSS (Really Simple Syndication), Web Services, and AJAX (Asynchronous JavaScript And XML), the Internet has facilitated the emergence of applications that are composed from a variety of services and data sources. Through tools such as Yahoo Pipes, these "mash-ups" can be composed in a dynamic, just-in-time manner from components provided by multiple institutions (i.e. Google, Amazon, your neighbour). However, when using these applications, it is not apparent where data comes from or how it is processed. Thus, to inspire trust and confidence in mash-ups, it is critical to be able to analyse their processes after the fact. These trailing analyses, in particular the determination of the provenance of a result (i.e. the process that led to it), are enabled by process documentation, which is documentation of an application's past process created by the components of that application at execution time. In this paper, we define a generic conceptual data model that supports the autonomous creation of attributable, factual process documentation for dynamic multi-institutional applications. The data model is instantiated using two Internet formats, OWL and XML, and is evaluated with respect to questions about the provenance of results generated by a complex bioinformatics mash-up
PReServ: Provenance Recording for Services
No full textThe importance of understanding the process by which a result was generated in an experiment is fundamental to science. Without such information, other scientists cannot replicate, validate, or duplicate an experiment. We define provenance as the process that led to a result. With large scale in-silico experiments, it becomes increasingly difficult for scientists to record process documentation that can be used to retrieve the provenance of a result. Provenance Recording for Services (PReServ) is a software package that allows developers to integrate process documentation recording into their applications. PReServ has been used by several applications and its performance has been benchmarked
The requirements of using provenance in e-Science experiments
No full textIn e-Science experiments, it is vital to record the experimental process for later use such as in interpreting results, verifying that the correct process took place or tracing where data came from. The process that led to some data is called the provenance of that data, and a provenance architecture is the software architecture for a system that will provide the necessary functionality to record, store and use process documentation to determine the provenance of data items. However, there has been little principled analysis of what is actually required of a provenance architecture, so it is impossible to determine the functionality they would ideally support. In this paper, we present use cases for a provenance architecture from current experiments in biology, chemistry, physics and computer science, and analyse the use cases to determine the technical requirements of a generic, technology and applicationindependent architecture. We propose an architecture that meets these requirements, analyse its features compared with other approaches and evaluate a preliminary implementation by attempting to realise two of the use cases
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