28 research outputs found
Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR
Substantial experimental and theoretical efforts worldwide are devoted to
explore the phase diagram of strongly interacting matter. At LHC and top RHIC
energies, QCD matter is studied at very high temperatures and nearly vanishing
net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was
created at experiments at RHIC and LHC. The transition from the QGP back to the
hadron gas is found to be a smooth cross over. For larger net-baryon densities
and lower temperatures, it is expected that the QCD phase diagram exhibits a
rich structure, such as a first-order phase transition between hadronic and
partonic matter which terminates in a critical point, or exotic phases like
quarkyonic matter. The discovery of these landmarks would be a breakthrough in
our understanding of the strong interaction and is therefore in the focus of
various high-energy heavy-ion research programs. The Compressed Baryonic Matter
(CBM) experiment at FAIR will play a unique role in the exploration of the QCD
phase diagram in the region of high net-baryon densities, because it is
designed to run at unprecedented interaction rates. High-rate operation is the
key prerequisite for high-precision measurements of multi-differential
observables and of rare diagnostic probes which are sensitive to the dense
phase of the nuclear fireball. The goal of the CBM experiment at SIS100
(sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD
matter: the phase structure at large baryon-chemical potentials (mu_B > 500
MeV), effects of chiral symmetry, and the equation-of-state at high density as
it is expected to occur in the core of neutron stars. In this article, we
review the motivation for and the physics programme of CBM, including
activities before the start of data taking in 2022, in the context of the
worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal
This document is under the terms of the CC-BY-NC-ND Creative Commons Attribution
We present Stellaris, the information service of the community project AstroGrid-D. Stellaris is the core component of the AstroGrid-D middleware that enables scientists to share their resources, provides access to large datasets and integrates instruments such as robotic telescopes. Besides the many diverse types of resources, the information service also supports a wide range of use cases each using a specific schema for the metadata. In addition, Stellaris addresses the distributed and dynamic nature of collaborations in the astronomers ’ community. Stellaris satisfies these requirements by adopting RDF and SPARQL for storing and querying metadata. Our paper focuses on the requirements of the community, presents the architecture of the information service in detail and discusses experiences with the prototype already in use by partners within the project.
Self-management of large-scale distributed systems by combining peer-to-peer networks and components
This report envisions making large-scale distributed applications self managing by combining component models and structured overlay networks. A key obstacle to deploying large-scale applications running on Internet is the amount of management they require. Often these applications demand specialized personnel for their maintenance. Making applications self managing will help removing this obstacle. Basing the system on a structured overlay network will allow extending the abilities of existing component models to large-scale distributed systems. A structured overlay network is a form of peer-to-peer network that provides strong guarantees on its behavior. The guarantees are provided for efficient communication, efficient load balancing, and self management in case of node joins, leaves
Error Detection with Directed Symbolic Model Checking
. In practice due to entailed memory limitations the most important problem in model checking is state space explosion. Therefore, to prove the correctness of a given design binary decision diagrams #BDDs# are widely used as a concise and symbolic state space representation. Nevertheless, BDDs are not able to avoid an exponential blow-up in general. If we restrict ourselves to #nd an error of a design which violates a safety property,inmany cases a complete state space exploration is not necessary and the introduction of a heuristic to guide the search can help to keep both the explored part and the associated BDD representation smaller than with the classical approach. In this paper we will show that this idea can be extended with an automatically generated heuristic and that it is applicable to a large class of designs. Since the proposed algorithm can be expressed in terms of BDDs it is even possible to use an existent model checker without any internal changes.
Les Greffes du plancher du sinus maxillaire à but pré-implantaire (intérêt de la technique décrite par Tulasne)
BORDEAUX2-BU Santé (330632101) / SudocPARIS-BIUM (751062103) / SudocPARIS-Bib. Serv.Santé Armées (751055204) / SudocSudocFranceF