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41.
In this paper, we study boundedness of integral operators on generalized Morrey spaces and its application to estimates in Morrey spaces for the Schrödinger operator with nonnegative (reverse Hölder class) and small perturbed potentials .

  相似文献   

42.
A quandle is a set with a binary operation satisfying certain conditions related to Reidemeister moves in knot theory. First we give an example of a quandle with subsets which are not subquandles but closed under the quandle operation. We introduce a method to produce a quandle from an invertible dynamical system. Our example is generalized to such dynamical quandles.  相似文献   
43.
Temperature dependence of positron annihilation lifetime spectra of polysilanes such as, poly(methyl-n-propylsilane) (PMPrS) and poly(di-n-hexylsilane) (PDHS) has been investigated. The τ3 in PMPrS is seen to increase monotonically around the solid–liquid transition temperature. The transition temperature and free volume are observed to depend on the molecular weight and/or packing of the backbones. For PDHS, a sharp change in τ3 and I3 is seen at the solid–solid transition temperature. Free volume radius probability density functions, above and below the transition temperature, are presented in PMPrS and PDHS. Positron studies are complimented by conventional thermal analysis studies.  相似文献   
44.
In this paper, we propose a new design for the recursive least-squares (RLS) Wiener fixed-lag smoother and filter in linear discrete-time wide-sense stationary stochastic systems. It is assumed that the signal is observed with additive white observation noise. The signal is uncorrelated with the observation noise. The estimators require knowledge of the system matrix, the observation matrix and the variance of the state vector. These quantities can be obtained from the auto-covariance function of the signal. In the estimation algorithms, moreover, the variance of the observation noise is assumed to be known, as a priori information.  相似文献   
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46.
Self-forming core/shell nanoparticles of magnetic metal/oxide with crystalline grain size of less than 40 nm were synthesized. The nanoparticles were highly concentrated in an insulating matrix to fabricate a nanocomposite, whose magnetic properties were investigated. The crystalline grain size of the nanoparticles strongly influenced the magnetic anisotropy field, magnetic coercivity, relative permeability, and loss factor (tan δ=μ″/μ′) at high frequency. The packing ratio of the magnetic metallic phase in the nanocomposite also influenced those properties. High permeability with low tan δ of less than 1.5% at up to 1 GHz was obtained in the case of the nanoparticles with crystalline grain size of around 15 nm with large packing ratio of the nanoparticles.  相似文献   
47.
Recent experimental values for the inclusive semileptonic decay branching ratio of theB meson are low compared to the spectator model expectation. That branching ratio is investigated in the right-handed current model. The right-handed current could enhance the nonleptonic decay mode, thereby suppressing the semileptonic branching ratio. Then, the quark mixing matrix of the right-handed sector is restricted to be of one special type and the right-handed neutrino has to be the heavy Dirac one.  相似文献   
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49.
Due to the large mass of top quark, CP violation in the top-quark decay is sensitive to the interactions mediated by Higgs bosons. We consider CP violation in tW + b decay by calculating consistently in unitary gauge the CP-violating up-down asymmetry of the leptons from W boson decays in tW + b, defined by Grz?dkowski and Gunion, in the two-Higgs doublet model with CP-violating neutral sector. The asymmetry is shown to be at most of the order of (1–4) × 10-4 for tan β = 1.0, where tan β is the ratio of vacuum expectation values for the two neutral Higgs bosons.  相似文献   
50.
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