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101.
Based on composite materials, the equivalent elastic-plastic constitutive equations of multiphase solid are researched. According to the suggested definition of constitutive equivalence it is demonstrated that the multiphase solid, composed of several kinds of homogeneous elastic-plastic media that conform to the generalized normality rule, has the same type of constitutive equations as its constituents have that also conform to the generalized normality rule. 相似文献
102.
We use lookback time versus redshift data from galaxy clusters (Capozziello et al., 2004 [9]) and passively evolving galaxies (Simon et al., 2005 [62]), and apply a Bayesian prior on the total age of the Universe based on WMAP measurements, to constrain dark energy cosmological model parameters. Current lookback time data provide interesting and moderately restrictive constraints on cosmological parameters. When used jointly with current baryon acoustic peak and Type Ia supernovae apparent magnitude versus redshift data, lookback time data tighten the constraints on parameters and favor slightly smaller values of the nonrelativistic matter energy density. 相似文献
103.
S. Tazhetdinov 《Siberian Mathematical Journal》2008,49(1):175-179
We describe the subnormal subgroups of 2-dimensional linear groups over local and full rings in which 2 is invertible, as well as the subnormal subgroups of symplectic groups over local rings in which 2 is invertible. 相似文献
104.
This short note proves that the least square nucleolus (Ruiz et al. (1996)) and the lexicographical solution (Sakawa and Nishizaki (1994)) select the same imputation in each game with nonempty imputation set. As a consequence the
least square nucleolus is a general nucleolus (Maschler et al. (1992)).
Received: December 1998/Revised version: July 1999 相似文献
105.
James B. Westgard 《Foundations of Physics Letters》1989,2(3):209-222
A family of trajectories of a single particle, parameterized by initial velocities on some space-like hypersurface, is somewhat analogous to streamline fluid flow. This model is applied to electromagnetism and gravity by introducing velocity and displacement fields. The resulting kinetic field equations are of simpler form than the original equations of motion, and have certain advantages for solution. The gravitational kinetic field equation is, in fact, linear. Some simple solutions are given for illustration. 相似文献
106.
Summary The experimental techniques developed to build a sensitive gravitational wave antenna can find application in many different
fields of research. In the present paper we discuss briefly two experiments that we are developing in the Istituto Fisica
Spazio Interplanetario of C.N.R. More precisely, a noncryogenic gravity gradiometer to be flown on the subsatellite of the
TSS and a cryogenic force sensor which will be used to verify some recent results on the interaction of neutrino with matter
are described.
To speed up publication the proofs were not sent to the authors and were superivised by the Scientific Committee. 相似文献
107.
BONNISSEAU J. M. FLORIG M. JOFRÉ A. 《Journal of Optimization Theory and Applications》2001,109(2):237-263
The purpose of this paper is to study the continuity and uniqueness properties of equilibria for linear exchange economies. We characterize the sets of utility vectors and initial endowments for which the equilibrium price is unique and respectively the set for which the equilibrium allocation is unique. We show that the equilibrium allocation correspondence is continuous with respect to the initial endowments and we characterize the set of full measure where the equilibrium allocation correspondence with respect to the initial endowments and utility vectors is continuous. 相似文献
108.
Paul Halpern 《Physics in Perspective (PIP)》2005,7(4):390-403
I explore the early life and contributions of Peter Bergmann (1915–2002), focusing on his family background, education, and
ideas. I examine how Bergmann’s formative years were shaped by the outspoken influence of his mother, a leading educational
reformer; the distinguished reputation of his father, a renowned materials chemist; and his cherished hope of working with
Albert Einstein (1879–1955), to whom he eventually became an assistant. Inspired by these and other notable thinkers, Bergmann
became an exemplary organizer, educator, and mentor in the fields of general relativity and quantum gravity. 相似文献
109.
QIAN Shang-Wu GU Zhi-Yu 《理论物理通讯》2005,44(2):243-246
There are three non-integrable phases in literatures: Berry phase, Aharonov-Anandan phase, and Yang phase. This article discusses the evolutions of Yang phase under the cyclic condition and the adiabatic condition for the general time-dependent harmonic oscillator, thus reveals the intimate relations between these three non-integrable phases. 相似文献
110.
On social percolation and small world network 总被引:1,自引:0,他引:1
E. Ahmed H.A. Abdusalam 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,16(3):569-571
The social percolation model is generalized to include the propagation of two mutually exclusive competing effects on a one-dimensional
ring and a two-dimensional square lattice. It is shown that the result depends significantly on which effect propagates first
i.e. it is a non-commutative phenomenon. Then the propagation of one effect is studied on a small network. It generalizes the
work of Moore and Newman of a disease spread to the case where the susceptibility of the population is random. Three variants
of the Domany-Kinzel model are given. One of them (delayed) does not have a chaotic region for some value of the delay weight.
Received 24 February 2000 相似文献