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961.
962.
Moon Fuk Chan Guansan Chen M. Süleyman Demokan Hwa Yaw Tam 《Optics and Lasers in Engineering》1998,30(1):17-24
The theory and experimental verification of an optical current sensor based on an extrinsic Sagnac interferometer configuration is presented. Superior performance with regard to current sensitivity and input/output linearity, and simple installability of the sensor makes it very suitable for remote current sensing in power distribution applications. 相似文献
963.
A comparison of complete global optimization solvers 总被引:2,自引:0,他引:2
Arnold Neumaier Oleg Shcherbina Waltraud Huyer Tamás Vinkó 《Mathematical Programming》2005,103(2):335-356
Results are reported of testing a number of existing state of the art solvers for global constrained optimization and constraint satisfaction on a set of over 1000 test problems in up to 1000 variables, collected from the literature.The test problems are available online in AMPL and were translated into the input formats of the various solvers using routines from the COCONUT environment. These translators are available online, too. 相似文献
964.
Let K1 and K2 be solid cones in Rn and Rm respectively, and let A be a linear operator such that AK1?K2. Necessary and sufficient conditions for the existence of various kinds of generalized inverses of A taking K2 into K1 are given. Projections which belong to π(K), the set of all linear operators that preserve a are studied. In particular, it is proved that a projection P in π(K) is a simplicial nonnegative linear combination of its rank-one operators iff Im P∩K is a simplical cone. An open question of Burns, Fiedler, and Haynsworth concerning minimal generating matrices of polyhedral cones is also extended and answered affirmatively. 相似文献
965.
C.K.W. Tam 《Journal of sound and vibration》1976,49(3):353-364
A theoretical study of the acoustic modes of a two-dimensional rectangular cavity is presented in this paper. It is found that for cavities with length to depth ratio of unity or larger the natural modes are heavily damped due to acoustic radiation. Numerical results for lower order modes are given. The physical significance of strong radiation damping on the onset of cavity tones induced by outside flow at low Mach number is discussed. 相似文献
966.
Starting from the normal cyano-acetate derivative 3b, obtained from the allo stereoisomer 3a via an unusual epimerization,1 the stereoselective totalsynthesis of (±)-dihydrocorynantheine (1a) was accomplished. 相似文献
967.
A real space renormalization group is formulated for continuum (off-lattice) percolation problems. It is applied to the system of overlapping discs with a variety of distributions of disc radii. Monte Carlo method is used for obtaining recursion relations. The results support universality: The Harris criterion seems to work for percolation. The position of the critical point shows stability against introducing a distribution in the disc radii.Supported in part by SFB 125 Aachen-Jülich-Köln 相似文献
968.
969.
Tamás S. Biró 《Acta Physica Hungarica A》1995,1(1):33-41
In order to match two complementary approaches to quark gluon plasma, namely the classical hamiltonian lattice gauge field simulation which uses the temporal axial gauge, and hot perturbative QCD which rather uses the Coulomb or the covariant gauge, we obtain a general expression for the hard thermal loop gluon propagator for a variety of non-background gauge fixing conditions. The Coulomb energy is shown to be independent of the gauge fixing condition. 相似文献
970.
Hon-Wah Tam 《Applied Mathematics Letters》2002,15(8):9189-993
The Kupershmidt five-field lattice is considered in this paper. By a dependent variable transformation, the Kupershmidt lattice is transformed into a bilinear form by the introduction of three auxiliary variables. We present a Bäcklund transformation and a nonlinear superposition formula for the Kupershmidt lattice. As an application of the results, soliton solutions are derived. 相似文献