The origin and acceleration theories of Ultrah High Energy Cosmic Rays (UHECRs) are still mesterious problem in modern physics and astrophysics. The acceleration of ultra high energy cosmic rays is conjectured to occur through interactions with electromagnetic fields in different astrophysical objects, like magnetic matter clumps, besides the well-known shock waves and elastic Fermi mechanisms. Based on this model, a considerable portion of the dynamics, that derives a charged particle parallel to a magnetic field B and under the influence of a force F, is assumed to be composed of acceleration by a non-magnetic force F || and a gyromotion along B direction plus drifts in the direction of F ⊥ . The model and its formalism are introduced, section 2 and section 3. Various examples for drift motions and accelerating forces are suggested, section 4. The configuration of the cosmic electromagnetic in different astophysical plasma aspects could play intrinsic role in the acceleration process of UHECRs. In a forthcoming work, a quantitative estimation of the energy gained by charged cosmic rays in various astrophysical objects will be evaluated.
The SU(3) Polyakov linear-sigma model (PLSM) in mean-field approximation is utilized in analyzing the chiral condensates σ u , σ d , σ s and the deconfinement order parameters φ,φ, at finite isospin asymmetry. The bulk thermodynamics including pressure density, interaction measure, susceptibility, and second-order correlations with baryon, strange and electric charge quantum numbers are studied in thermal and dense medium. The PLSM results are confronted to the available lattice QCD calculations. The excellent agreement obtained strengthens the reliability of fixing the PLSM parameters and therefore supports further predictions even beyond the scope of the lattice QCD numerical applicability. From the QCD phase structure at finite isospin chemical potential (µ I ), a novel expression for the explicit symmetry breaking term h 3 is introduced, we find that the pseudocritical temperatures decrease with the increase in µ I . We conclude that the QCD phase structure in (T χ -µ I ) plane seems to extend the one in (T χ -µ B ) plane.
We compare results from the Polyakov linear-sigma model (PLSM) in optimized perturbation theory (OPT) with the mean-field approximation (MFA). At finite temperatures and chemical potentials, the chiral condensates and the decofinement order parameters, the thermodynamic pressure, the pseudo-critical temperatures, the subtracted condensates, the second-and high-order moments of various conserved charges (cumulants) obtained in MFA are compared with OPT and also confronted to available lattice QCD simulations. We conclude that when moving from lower-to higher-order moments of various quantum charges, OPT becomes more closer to QCD.
The main objective of this study is to develop a Strategic Asset Management Framework (SAMF) for educational buildings in Egypt. The General Authority for Educational Buildings (GAEB) was chosen as a case study as it represents the biggest governmental organization responsible for planning, operating and maintaining schools in Egypt. This is achieved first through reviewing the literature of strategic asset management. In the next stage, structured interviews were conducted with senior managers of GAEB using a pre designed questionnaire to explore the current practice of asset management (AM). Gap analysis technique was applied against best practices compounded from a vast literature review and showed that the areas related to ''people and organization'' category are the weakest areas. Based on the findings, a SAMF for GAEB was developed. The study developed a checklist to be applied as a multifunctional tool for framework implementation and self assessment of asset management maturity. The developed checklist tool and its mechanism not only assess the overall AM maturity but also allow assessing the detailed step by step level of implementation of the framework. The framework was developed to improve GAEB AM performance and to reach at least the ''Systematic Approach'' level as a first stage in the improvement process. The framework has been implemented and the overall performance achieved the target score that lies in the range of Systematic Approach level, more over the areas related to ''people and organization'' category which represented a main weakness in GAEB have achieved a remarkable improvement.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.