726,725 research outputs found
The evolution of tropos: Contexts, commitments and adaptivity
Software evolution is the main research focus of the Tropos group at University of Trento (UniTN): how do we build systems that are aware of their requirements, and are able to dynamically reconfigure themselves in response to changes in context (the environment within which they operate) and requirements. The purpose of this report is to offer an overview of ongoing work at UniTN. In particular, the report presents ideas and results of four lines of research: contextual requirements modeling and reasoning, commitments and goal models, developing self-reconfigurable systems, and requirements awareness
The Trigger System of the CMS Experiment
We give an overview of the main features of the CMS trigger and data
acquisition (DAQ) system. Then, we illustrate the strategies and trigger
configurations (trigger tables) developed for the detector calibration and
physics program of the CMS experiment, at start-up of LHC operations, as well
as their possible evolution with increasing luminosity. Finally, we discuss the
expected CPU time performance of the trigger algorithms and the CPU
requirements for the event filter farm at start-up.Comment: Presented at the 10th International Conference On Instrumentation For
Colliding Beam Physics (INSTR08), 28 Feb - 5 Mar 2008, Novosibirsk, Russi
Technology for Space Station Evolution. Executive summary and overview
NASA's Office of Aeronautics and Space Technology (OAST) conducted a workshop on technology for space station evolution 16-19 Jan. 1990. The purpose of this workshop was to collect and clarify Space Station Freedom technology requirements for evolution and to describe technologies that can potentially fill those requirements. These proceedings are organized into an Executive Summary and Overview and five volumes containing the technology discipline presentations. The Executive Summary and Overview contains an executive summary for the workshop, the technology discipline summary packages, and the keynote address. The executive summary provides a synopsis of the events and results of the workshop and the technology discipline summary packages
Context Aware Adaptable Applications - A global approach
Actual applications (mostly component based) requirements cannot be expressed without a ubiquitous and mobile part for end-users as well as for M2M applications (Machine to Machine). Such an evolution implies context management in order to evaluate the consequences of the mobility and corresponding mechanisms to adapt or to be adapted to the new environment. Applications are then qualified as context aware applications. This first part of this paper presents an overview of context and its management by application adaptation. This part starts by a definition and proposes a model for the context. It also presents various techniques to adapt applications to the context: from self-adaptation to supervised approached. The second part is an overview of architectures for adaptable applications. It focuses on platforms based solutions and shows information flows between application, platform and context. Finally it makes a synthesis proposition with a platform for adaptable context-aware applications called Kalimucho. Then we present implementations tools for software components and a dataflow models in order to implement the Kalimucho platform
Introduction of laser initiation for the 48-inch Advanced Solid Rocket Motor (ASRM) test motors at Marshall Space Flight Center (MSFC)
The Advanced Solid Rocket Motor is a new design for the Space Shuttle Solid Rocket Booster. The new design will provide more thrust and more payload capability, as well as incorporating many design improvements in all facets of the design and manufacturing process. A 48-inch (diameter) test motor program is part of the ASRM development program. This program has multiple purposes for testing of propellent, insulation, nozzle characteristics, etc. An overview of the evolution of the 48-inch ASRM test motor ignition system which culminated with the implementation of a laser ignition system is presented. The laser system requirements, development, and operation configuration are reviewed in detail
Single and binary stellar progenitors of long-duration gamma-ray bursts
This review describes the most common theories behind long-duration gamma-ray
burst progenitors. I discuss two astrophysical scenarios: the collapsar and the
magnetar models. According to their requirements, the progenitor should be an
envelope-free massive star with a fast rotating, collapsing iron core. Such an
object, called a TWUIN star, may be produced by chemically homogeneous
evolution either from a massive single star or a massive binary system. Various
outcomes of this evolutionary path (e.g. supernova explosions and gravitational
wave production) are also mentioned, and directions for future research are
suggested. In the era of multi-messenger astronomy, my hope is to present a
timely overview on how stellar astrophysicists are searching for progenitor
models of long-duration gamma-ray bursts, and what they have found so far.Comment: Proceedings of the XII Multifrequency Behaviour of High Energy Cosmic
Sources Workshop, 12-17 June, 2017, Palermo, Ital
Technology for Space Station Evolution. Volume 4: Power Systems/Propulsion/Robotics
NASA's Office of Aeronautics and Space Technology (OAST) conducted a workshop on technology for space station evolution on 16-19 Jan. 1990. The purpose of this workshop was to collect and clarify Space Station Freedom technology requirements for evolution and to describe technologies that can potentially fill those requirements. These proceedings are organized into an Executive Summary and Overview and five volumes containing the Technology Discipline Presentations. Volume 4 consists of the technology discipline sections for Power, Propulsion, and Robotics. For each technology discipline, there is a Level 3 subsystem description, along with the papers
Evolution of security engineering artifacts: a state of the art survey
Security is an important quality aspect of modern open software systems. However, it is challenging to keep such systems secure because of evolution. Security evolution can only be managed adequately if it is considered for all artifacts throughout the software development lifecycle. This article provides state of the art on the evolution of security engineering artifacts. The article covers the state of the art on evolution of security requirements, security architectures, secure code, security tests, security models, and security risks as well as security monitoring. For each of these artifacts the authors give an overview of evolution and security aspects and discuss the state of the art on its security evolution in detail. Based on this comprehensive survey, they summarize key issues and discuss directions of future research
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