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91.
Evaldo M. F. Curado Sofiane Faci Jean-Pierre Gazeau Diego Noguera 《Entropy (Basel, Switzerland)》2022,24(2)
In quantum information processing, using a receiver device to differentiate between two non-orthogonal states leads to a quantum error probability. The minimum possible error is known as the Helstrom bound. In this work, we study the conditions for state discrimination using an alphabet of squeezed coherent states and compare them with conditions using the Glauber-Sudarshan, i.e., standard, coherent states. 相似文献
92.
93.
Projected gradient methods for linearly constrained problems 总被引:23,自引:0,他引:23
The aim of this paper is to study the convergence properties of the gradient projection method and to apply these results
to algorithms for linearly constrained problems. The main convergence result is obtained by defining a projected gradient,
and proving that the gradient projection method forces the sequence of projected gradients to zero. A consequence of this
result is that if the gradient projection method converges to a nondegenerate point of a linearly constrained problem, then
the active and binding constraints are identified in a finite number of iterations. As an application of our theory, we develop
quadratic programming algorithms that iteratively explore a subspace defined by the active constraints. These algorithms are
able to drop and add many constraints from the active set, and can either compute an accurate minimizer by a direct method,
or an approximate minimizer by an iterative method of the conjugate gradient type. Thus, these algorithms are attractive for
large scale problems. We show that it is possible to develop a finite terminating quadratic programming algorithm without
non-degeneracy assumptions.
Work supported in part by the Applied Mathematical Sciences subprogram of the Office of Energy Research of the U.S. Department
of Energy under Contract W-31-109-Eng-38.
Work supported in part by the Applied Mathematical Sciences subprogram of the Office of Energy Research of the U.S. Department
of Energy under Contract W-31-109-Eng-38. 相似文献
94.
Let G=(V,E) be a graph.A set S■V is a restrained dominating set if every vertex in V-S is adjacent to a vertex in S and to a vertex in V-S.The restrained domination number of G,denoted γr(G),is the smallest cardinality of a restrained dominating set of G.In this paper,we show that if G is a graph of order n≥4,then γr(G)γr(G)≤2n.We also characterize the graphs achieving the upper bound. 相似文献
95.
In this paper, the Hermitian positive definite solutions of the nonlinear matrix equation X^s - A^*X^-tA = Q are studied, where Q is a Hermitian positive definite matrix, s and t are positive integers. The existence of a Hermitian positive definite solution is proved. A sufficient condition for the equation to have a unique Hermitian positive definite solution is given. Some estimates of the Hermitian positive definite solutions are obtained. Moreover, two perturbation bounds for the Hermitian positive definite solutions are derived and the results are illustrated by some numerical examples. 相似文献
96.
根据单个保单理赔额分布函数F(z)的一些特殊性质,研究了开放个别风险模型在保单个数N为Poisson分布下,总理赔额分布函数F_S(x)对任意x(x≥0)的界值问题,得到一些实用的、便于数值计算的界值结果,具有重要的应用价值. 相似文献
97.
An imaginary potential with universal normalization for dissipative processes in heavy-ion reactions
D. Pereira J. Lubian J.R.B. Oliveira D.P. de Sousa L.C. Chamon 《Physics letters. [Part B]》2009,670(4-5):330-335
In this work we present new coupled channel calculations with the São Paulo potential (SPP) as the bare interaction, and an imaginary potential with system and energy independent normalization that has been developed to take into account dissipative processes in heavy-ion reactions. This imaginary potential is based on high-energy nucleon interaction in nuclear medium. Our theoretical predictions for energies up to ≈100 MeV/nucleon agree very well with the experimental data for the p,n+nucleus, 16O + 27Al, 16O + 60Ni, 58Ni + 124Sn, and weakly bound projectile 7Li + 120Sn systems. 相似文献
98.
This article deals with the proton migration in a tyrosine stack, which models the proton channels existing in a number of proteins, including tubulin. The magnesium ion Mg2+ within the complex with guanosine triphosphate facilitates dissociation of a water molecule through initiating a shift of protons along the chain composed of relatively distant tyrosine residues. The process is thermodynamically stable (ΔG298<0). The energy barrier for the protein shift does not exceed 3.15 kJ/mole. A relatively weak electrostatic field mimicking electret properties of proteins facilitates long‐distance proton migration. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 409–415, 2001 相似文献
99.
In this paper a new ring-shaped harmonic oscillator for spin 1/2 particles is studied, and the corresponding eigenfunctions and eigenenergies are obtained by solving the Dirac equation with equal mixture of vector and scalar potentials. Several particular cases such as the ring-shaped non-spherical harmonic oscillator, the ring-shaped harmonic oscillator, non-spherical harmonic oscillator, and spherical harmonic oscillator are also discussed. 相似文献
100.
This paper obtains an entangled condition for isotropic-like states by using an atomic map. It constructs a class of bound entangled states from the entangled condition and shows that the partial transposition of the state from the constructed bound entangled class is an edge bound entangled state by using range criterion. 相似文献