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81.
A. P. Afanasiev I. V. Bychkov O. S. Zaikin M. O. Manzyuk M. A. Posypkin A. A. Semenov 《Journal of Computer and Systems Sciences International》2017,56(4):701-707
A new concept of a multitask distributed heterogeneous computing system is proposed. The basic principles of such system are that it uses only idle supercomputer resources and does it as a common user; thus, it does not conflict with the administration policy in any way. The efficiency of the proposed concept is demonstrated by the example of the real grid system that currently uses supercomputer resources to boost the performance of the SAT@home and OPTIMA@home volunteer distributed computing projects. 相似文献
82.
83.
micrOMEGAs 2.0 is a code which calculates the relic density of a stable massive particle in an arbitrary model. The underlying assumption is that there is a conservation law like R-parity in supersymmetry which guarantees the stability of the lightest odd particle. The new physics model must be incorporated in the notation of CalcHEP, a package for the automatic generation of squared matrix elements. Once this is done, all annihilation and coannihilation channels are included automatically in any model. Cross-sections at v=0, relevant for indirect detection of dark matter, are also computed automatically. The package includes three sample models: the minimal supersymmetric standard model (MSSM), the MSSM with complex phases and the NMSSM. Extension to other models, including non-supersymmetric models, is described.
Program summary
Title of program:micrOMEGAs2.0Catalogue identifier:ADQR_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADQR_v2_0Program obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputers for which the program is designed and others on which it has been tested:PC, Alpha, Mac, SunOperating systems under which the program has been tested:UNIX (Linux, OSF1, SunOS, Darwin, Cygwin)Programming language used:C and FortranMemory required to execute with typical data:17 MB depending on the number of processes requiredNo. of processors used:1Has the code been vectorized or parallelized:noNo. of lines in distributed program, including test data, etc.:91 778No. of bytes in distributed program, including test data, etc.:1 306 726Distribution format:tar.gzExternal routines/libraries used:noCatalogue identifier of previous version:ADQR_v1_3Journal reference of previous version:Comput. Phys. Comm. 174 (2006) 577Does the new version supersede the previous version:yesNature of physical problem:Calculation of the relic density of the lightest stable particle in a generic new model of particle physics.Method of solution: In numerically solving the evolution equation for the density of dark matter, relativistic formulae for the thermal average are used. All tree-level processes for annihilation and coannihilation of new particles in the model are included. The cross-sections for all processes are calculated exactly with CalcHEP after definition of a model file. Higher-order QCD corrections to Higgs couplings to quark pairs are included.Reasons for the new version:There are many models of new physics that propose a candidate for dark matter besides the much studied minimal supersymmetric standard model. This new version not only incorporates extensions of the MSSM, such as the MSSM with complex phases, or the NMSSM which contains an extra singlet superfield but also gives the possibility for the user to incorporate easily a new model. For this the user only needs to redefine appropriately a new model file.Summary of revisions:- •
- Possibility to include in the package any particle physics model with a discrete symmetry that guarantees the stability of the cold dark matter candidate (LOP) and to compute the relic density of CDM.
- •
- Compute automatically the cross-sections for annihilation of the LOP at small velocities into SM final states and provide the energy spectra for final states.
- •
- For the MSSM with input parameters defined at the GUT scale, the interface with any of the spectrum calculator codes reads an input file in the SUSY Les Houches Accord format (SLHA).
- •
- Implementation of the MSSM with complex parameters (CPV-MSSM) with an interface to CPsuperH to calculate the spectrum.
- •
- Routine to calculate the electric dipole moment of the electron in the CPV-MSSM.
- •
- In the NMSSM, new interface compatible with NMHDECAY2.1.
84.
I. A. Sobolev A. É. Arustamov V. V. Shiryaev M. I. Ozhovan K. N. Semenov M. B. Kachalov 《Atomic Energy》1993,74(6):499-501
Radon Scientific Planning Department, Moscow. Translated from Atomnaya Énergiya, Vol. 74, No. 6, pp. 531-533, June, 1993. 相似文献
85.
Problems of Information Transmission - In the first part of this article, we answer Kolmogorov's question (stated in 1963 in [1]) about exact conditions for the existence of random generators.... 相似文献
86.
A number of high-precision pressure sensors for automatic regulation and monitoring systems are presented. The design-technological principles used in the sensors, which ensure their operating capability under severe operating conditions, are considered. A comparative analysis of the technical level of the sensors and their foreign analogs is given. 相似文献
87.
PW Roelvink A Lizonova JG Lee Y Li JM Bergelson RW Finberg DE Brough I Kovesdi TJ Wickham 《Canadian Metallurgical Quarterly》1998,72(10):7909-7915
Attachment of an adenovirus (Ad) to a cell is mediated by the capsid fiber protein. To date, only the cellular fiber receptor for subgroup C serotypes 2 and 5, the so-called coxsackievirus-adenovirus receptor (CAR) protein, has been identified and cloned. Previous data suggested that the fiber of the subgroup D serotype Ad9 also recognizes CAR, since Ad9 and Ad2 fiber knobs cross-blocked each other's cellular binding. Recombinant fiber knobs and 3H-labeled Ad virions from serotypes representing all six subgroups (A to F) were used to determine whether the knobs cross-blocked the binding of virions from different subgroups. With the exception of subgroup B, all subgroup representatives cross-competed, suggesting that they use CAR as a cellular fiber receptor as well. This result was confirmed by showing that CAR, produced in a soluble recombinant form (sCAR), bound to nitrocellulose-immobilized virions from the different subgroups except subgroup B. Similar results were found for blotted fiber knob proteins. The subgroup F virus Ad41 has both short and long fibers, but only the long fiber bound sCAR. The sCAR protein blocked the attachment of all virus serotypes that bound CAR. Moreover, CHO cells expressing human CAR, in contrast to untransformed CHO cells, all specifically bound the sCAR-binding serotypes. We conclude therefore that Ad serotypes from subgroups A, C, D, E, and F all use CAR as a cellular fiber receptor. 相似文献
88.
专家系统是人工智能的一个分支,是一种模拟专家决策能力的计算机系统,知识库是系统的重要组成部分,是系统的核心。本文结合纺织工艺设计及管理专家系统介绍了基于知识的专家系统的概念和结构,对系统中知识的获取、存储方式予以说明.并对其知识的表示方法加以阐述。 相似文献
89.
L. REIS A. FONSECA M. DE FREITAS 《Fatigue & Fracture of Engineering Materials & Structures》2004,27(9):873-877
This work describes the present methodology used on Portuguese Air Force (PoAF) aircrafts for fatigue life assessment to maintain its structural integrity. This methodology uses experimental flight data collected by airborne instrumentation systems. The recorded data are analysed for the prediction of the crack growth of defects at critical components of the aircraft and this information is then used for planning non‐destructive inspections, maintenance, logistical support and operational usage of the various fleets. This methodology is exemplified by one application on DASSAULT/DORNIER ALPHA‐JET aircraft. 相似文献
90.
Abstract The propagation of a television (TV) signal is usually perturbed during periods of atmospheric disturbance such as in thunderstorms. The region under investigation here is situated in the coastal area of the Bay of Bengal and has experienced frequent thunderstorm activities. An investigation to study their effects on VHF signal propagation transmitted from Satkhira in Bangladesh and received at the Indian Statistical Institute, Calcutta, has been undertaken. The depths of the atmospheric disturbances within a 1?km range have been recorded and measured by acoustic sounder (sodar) operated continuously at the receiving station. The inset of the storm is marked by the enhanced signal level with deep fluctuations characteristic during the periods of thunderstorms. 相似文献