147 research outputs found
ESAF-Simulation of the EUSO-Balloon
For the JEM-EUSO CollaborationThe EUSO-Balloon is a balloon borne ultraviolet (UV) telescope, which is being developed as a pathfinder of the JEM-EUSO mission (Extreme Universe Space Observatory onboard the Japanese Experiment Module on the International Space Station (ISS), see this conference proceedings). Designed as a scaled version of JEM-EUSO, the EUSO-Balloon will serve as a technology demonstrator. From 2014 on, it is planned to conduct a number of missions, between a few and several tens of hours at an altitude of approx. 40 km. Besides proving the robustness of the JEM-EUSO technology it will perform UV background studies under many different ground conditions and potentially observe extended air showers (EAS) induced by ultra-high-energy cosmic rays (UHECR) of the order of 10^18 eV. The detector design consists of a system of Fresnel lenses focussing the incoming 300 - 400 nm UV fluorescence photons onto an array of multi-anode photomultipliers. Generated photoelectrons are then readout by the front end electronics, converted into digital data and saved to disc if a trigger is issued. The ESAF (EUSO Simulation and Analysis Framework) software package is designed to simulate space based observation of EAS, taking into account every physical process from EAS generation, progagation of light in atmosphere, detector response and eventually reconstruction. EUSO-Balloon specifications such as the optics and dedicated electronics components have been implemented in the code to study the expected instrument behavior and its ability to resolve the UHECR arrival direction. In this poster we describe ESAF simuations of the EUSO-Balloon. Furthermore, we present results concerning the expected performance in terms of spatial resolution and background studies
Domain Specific Languages for Managing Feature Models: Advances and Challenges
International audienceManaging multiple and complex feature models is a tedious and error-prone activity in software product line engineering. Despite many advances in formal methods and analysis techniques, the supporting tools and APIs are not easily usable together, nor unified. In this paper, we report on the development and evolution of the Familiar Domain-Specific Language (DSL). Its toolset is dedicated to the large scale management of feature models through a good support for separating concerns, composing feature models and scripting manipulations. We overview various applications of Familiar and discuss both advantages and identified drawbacks. We then devise salient challenges to improve such DSL support in the near future
Haiku - a Scala combinator toolkit for semi-automated composition of metaheuristics
There is an emerging trend towards the automated design of metaheuristics at the software component level. In principle, metaheuristics have a relatively clean decomposition, where well-known frameworks such as ILS and EA are parametrised by variant components for acceptance, perturbation etc. Automated generation of these frameworks is not so simple in practice, since the coupling between components may be implementation specific. Compositionality is the ability to freely express a space of designs âbottom upâ in terms of elementary components: previous work in this area has used combinators, a modular and functional approach to componentisation arising from foundational Computer Science. In this article, we describeHaiku, a combinator tool-kit written in the Scala language, which builds upon previous work to further automate the process by automatically composing the external dependencies of components. We provide examples of use and give a case study in which a programatically-generated heuristic is applied to the Travelling Salesman Problem within an Evolutionary Strategies framework
LEESA: Embedding Strategic and XPath-Like Object Structure Traversals in C++
Abstract. Traversals of heterogeneous object structures are the most common operations in schema-first applications where the three key is-sues are (1) separation of traversal specifications from type-specific ac-tions, (2) expressiveness and reusability of traversal specifications, and (3) supporting structure-shy traversal specifications that require min-imal adaptation in the face of schema evolution. This paper presents Language for Embedded quEry and traverSAl (LEESA), which pro-vides a generative programming approach to address the above issues. LEESA is an object structure traversal language embedded in C++. Using C++ templates, LEESA combines the expressiveness of XPathâs axes-oriented traversal notation with the genericity and programmabil-ity of Strategic Programming. LEESA uses the object structure meta-information to statically optimize the traversals and check their compat-ibility against the schema. Moreover, a key usability issue of domain-specific error reporting in embedded DSL languages has been addressed in LEESA through a novel application of Concepts, which is an upcoming C++ standard (C++0x) feature. We present a quantitative evaluation of LEESA illustrating how it can significantly reduce the development efforts of schema-first applications.
Performances of JEM-EUSO
In this paper we describe the requirements and the expected performances of JEM-EUSO. Designed as the first mission to explore the Ultra High Energy Universe from space, JEM-EUSO will monitor the earth's atmosphere at night to record the UV (300â400 nm) tracks generated by the Extensive Air Showers produced by Ultra High Energy primaries propagating in the atmosphere. After briefing summarizing the main aspects of the JEM-EUSO Instrument and mission baseline, we will present, in details, our studies of the expected trigger rate, the estimated exposure, as well as on the expected angular, energy, and Xmax resolution. Eventually, the obtained results will be discussed in the context of the scientific requirements of the mission
Energy savings and speedups from partitioning critical software loops to hardware in embedded systems
The eROSITA X-ray telescope on SRG
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the primary instrument on the Spectrum-Roentgen-Gamma (SRG) mission, which was successfully launched on July 13, 2019, from the Baikonour cosmodrome. After the commissioning of the instrument and a subsequent calibration and performance verification phase, eROSITA started a survey of the entire sky on December 13, 2019. By the end of 2023, eight complete scans of the celestial sphere will have been performed, each lasting six months. At the end of this program, the eROSITA all-sky survey in the soft X-ray band (0.2-2.3 keV) will be about 25 times more sensitive than the ROSAT All-Sky Survey, while in the hard band (2.3-8 keV) it will provide the first ever true imaging survey of the sky. The eROSITA design driving science is the detection of large samples of galaxy clusters up to redshifts z > 1 in order to study the large-scale structure of the universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of a few million AGNs, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars, and diffuse emission within the Galaxy. Results from early observations, some of which are presented here, confirm that the performance of the instrument is able to fulfil its scientific promise. With this paper, we aim to give a concise description of the instrument, its performance as measured on ground, its operation in space, and also the first results from in-orbit measurements
Performances of JEM-EUSO
In this paper we describe the requirements and the expected performances of JEM-EUSO. Designed as the first mission to explore the Ultra High Energy Universe from space, JEM-EUSO will monitor the earth's atmosphere at night to record the UV (300â400 nm) tracks generated by the Extensive Air Showers produced by Ultra High Energy primaries propagating in the atmosphere. After briefing summarizing the main aspects of the JEM-EUSO Instrument and mission baseline, we will present, in details, our studies of the expected trigger rate, the estimated exposure, as well as on the expected angular, energy, and Xmax resolution. Eventually, the obtained results will be discussed in the context of the scientific requirements of the mission
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