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    Note On Certain Inequalities for Neuman Means

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    In this paper, we give the explicit formulas for the Neuman means NAHN_{AH}, NHAN_{HA}, NACN_{AC} and NCAN_{CA}, and present the best possible upper and lower bounds for theses means in terms of the combinations of harmonic mean HH, arithmetic mean AA and contraharmonic mean CC.Comment: 9 page

    Solving a class of matrix minimization problems by linear variational inequality approaches

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    AbstractA class of matrix optimization problems can be formulated as a linear variational inequalities with special structures. For solving such problems, the projection and contraction method (PC method) is extended to variational inequalities with matrix variables. Then the main costly computational load in PC method is to make a projection onto the semi-definite cone. Exploiting the special structures of the relevant variational inequalities, the Levenberg–Marquardt type projection and contraction method is advantageous. Preliminary numerical tests up to 1000×1000 matrices indicate that the suggested approach is promising

    Systematic investigation of the rotational bands in nuclei with Z≈100Z \approx 100 using a particle-number conserving method based on a cranked shell model

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    The rotational bands in nuclei with Z≈100Z \approx 100 are investigated systematically by using a cranked shell model (CSM) with the pairing correlations treated by a particle-number conserving (PNC) method, in which the blocking effects are taken into account exactly. By fitting the experimental single-particle spectra in these nuclei, a new set of Nilsson parameters (κ\kappa and μ\mu) and deformation parameters (ε2\varepsilon_2 and ε4\varepsilon_4) are proposed. The experimental kinematic moments of inertia for the rotational bands in even-even, odd-AA and odd-odd nuclei, and the bandhead energies of the 1-quasiparticle bands in odd-AA nuclei, are reproduced quite well by the PNC-CSM calculations. By analyzing the ω\omega-dependence of the occupation probability of each cranked Nilsson orbital near the Fermi surface and the contributions of valence orbitals in each major shell to the angular momentum alignment, the upbending mechanism in this region is understood clearly.Comment: 21 pages, 24 figures, extended version of arXiv: 1101.3607 (Phys. Rev. C83, 011304R); added refs.; added Fig. 4 and discussions; Phys. Rev. C, in pres
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