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141.
Using the Chern classes defined by Grothendieck, we map aK-theoretic invariant of invertible symmetric matrices defined by Giffen to the Clifford invariant.According to Herrmann Graßman'sWörterbuch zum Rig-veda, Ketu may not be connected with K2 but es bezeichnet das, was sich sichtbar oder kenntlich macht ... 相似文献
142.
In this paper we propose a model of HIV population through method of phases with non-Markovian evolution of immigration. The analysis leads to an explicit differential equations for the generating functions of the total population size. The detection process of antibodies (against the antigen of virus) is analysed and an explicit expression for the correlation functions are provided. A measure of bunching is also introduced for some particular choice of parameters. 相似文献
143.
This paper pertains to a detailed simulation study conducted on a typical Flexible Manufacturing System (FMS). Initially, the configurations of the FMS under study have been established. Two types of FMSs have been evolved: one is failure free and the other is failure prone. For each of these cases, simulation models have been developed using SLAMSYSTEM. Orders arriving randomly at the FMS are subjected to three levels of scheduling decisions namely, launching of parts into the system, routing of parts through machines and sequencing of parts on AGVs at a central buffer. The simulation results have been used to develop metamodels for the two types of FMSs. These metamodels have been subjected to statistical analysis to ascertain their adequacy to represent the simulation models. These metamodels have been found to be useful for simulating the FMSs under study so as to evaluate various multi-level scheduling decisions in the FMS. 相似文献
144.
R. Parimala R. Sridharan Maneesh L. Thakur 《Transactions of the American Mathematical Society》1998,350(3):1277-1284
Let be a field whose characteristic is different from 2 and 3 and let be a quadratic extension. In this paper we prove that for a fixed, degree 3 central simple algebra over with an involution of the second kind over , the Jordan algebra , obtained through Tits' second construction is determined up to isomorphism by the class of in , thus settling a question raised by Petersson and Racine. As a consequence, we derive a ``Skolem Noether' type theorem for Albert algebras. We also show that the cohomological invariants determine the isomorphism class of , if is fixed.
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In this paper we present a technique to optimize the transport parameters for transverse matching of the space charge dominated beams in the presence of bunching. The increase in the current within the specified bunch width during the transport is obtained from the disc model and is included in the optimization method. A 2D particle in cell (PIC) code is then developed to study the details transverse dynamics of the bunch taking into account the effect of longitudinal compression by reweighting the charge and mass of macroparticles. The evolution of rms beam size obtained using PIC simulation agrees well with the results obtained by solving beam envelope equation. The PIC simulation shows emittance growth during bunching induced by the space charge effect for nonuniform distribution. The growth in the emittance increases with the nonlinearity of distribution and peaks near the time focus. 相似文献
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The finite temperature effective potential for a scalar field with Φ6 interaction is calculated by extending the CJT formalism for composite operators. It is found that unrenormalized terms appear
in the effective potential due to the presence of an unrenormalized mass term. Nonzero turning points are obtained both for
positive and negativeλ. High temperature expansion is performed and the results are analysed numerically. Graphical analysis indicates symmetry
restoration whenT→0. 相似文献