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The study of exoplanets (planets orbiting other stars) is revolutionizing the way we view our universe. High-precision photometric data provided by the Kepler Space Telescope (Kepler) enables not only the detection of such planets, but also their characterization. This presents a unique opportunity to apply Bayesian methods to better characterize the multitude of previously confirmed exoplanets. This paper focuses on applying the EXONEST algorithm to characterize the transiting short-period-hot-Jupiter, HAT-P-7b (also referred to as Kepler-2b). EXONEST evaluates a suite of exoplanet photometric models by applying Bayesian Model Selection, which is implemented with the MultiNest algorithm. These models take into account planetary effects, such as reflected light and thermal emissions, as well as the effect of the planetary motion on the host star, such as Doppler beaming, or boosting, of light from the reflex motion of the host star, and photometric variations due to the planet-induced ellipsoidal shape of the host star. By calculating model evidences, one can determine which model best describes the observed data, thus identifying which effects dominate the planetary system. Presented are parameter estimates and model evidences for HAT-P-7b. [ABSTRACT FROM AUTHOR]

Computer systems with GPUs are expected to become a strong methodology for high-speed encryption processing. Moreover, power consumption is a primary deterrent for data center security on cloud services and handheld devices such as smartphones and tablet PCs. On the other hand, GPU vendors currently announce their future roadmaps of GPU architecture development, Nvidia Corp. accentuates Kepler architecture and AMD Corp. does GCN architecture. That's why in this paper we evaluated throughput and power efficiency of three 128-bit block ciphers on GPUs with recent Nvidia Kepler and AMD GCN architectures. In accordance with our experiments, whereas the throughput and per-watt throughput of AES-128 on Radeon HD 7970 (2048 cores) with GCN architecture is respectively extremely high 219.9 Gbps and 1310.7 Mbps/W, those on Geforce GTX 680 (1536 cores) with Kepler architecture be respectively considerably low 68.6 Gbps and 471.7 Mbps/W. Next, in order to investigate this mysterious experimental result, we used our micro-benchmark suites. They cleared up the reason, arithmetic logical instructions are required by encryption processing but are eliminated from some of the processing cores in Kepler architecture, unlike GCN's. [ABSTRACT FROM PUBLISHER]

This paper presents an overview of the new developments carried out to offer a reliable and efficient support for different computing infrastructures in the Kepler workflow orchestration system. The aim of the work is to help scientists to transparently use these infrastructures regardless of the underlying middleware. We introduce new complex workflow scenarios developed in the context of the EU EGI Inspire project and their exploitation by two nuclear fusion applications. The presented use cases represent typical scenarios which are common also in other fields and could be easily reused for other applications. [ABSTRACT FROM PUBLISHER]

This paper describes chosen aspects of the European Integrated Tokamak Modelling Task Force (ITM-TF) effort. It covers topics related to latest developments towards providing fusion scientists with a software framework for fusion modeling and simulation. The proposed framework provides researchers with an easy to use, workflow based environment for scientific computations. It allows the execution of various applications in numerous distributed computational resources directly from a user friendly, intuitive interface. We present the latest advances in the development of easy to use tools allowing the integration of the physics codes into the scientific workflows that schedule jobs to different infrastructures. The presented approach provides a simple way to access extensive computational resources and hides the complexity of the process at the same time. It allows for easy extension of existing simulation scenarios and fast prototyping. Some aspects of interactive communication between workflow environment and running jobs are discussed. Results of two practical use cases are presented in the context of the discussed workflow based solution: a parametric study and a plasma turbulence workflow. [ABSTRACT FROM PUBLISHER]

This is a short review of the evolution of ideas and concepts about the Universe. It is based on the introductory talk given on the 25 of July 2008 within the Third School on Cosmic Rays and Astrophysics held in Arequipa, Peru. [ABSTRACT FROM AUTHOR]