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991.
Mohammad Reza Kazemi Saeid Tahmasebi Francesco Buono Maria Longobardi 《Entropy (Basel, Switzerland)》2021,23(5)
Deng entropy and extropy are two measures useful in the Dempster–Shafer evidence theory (DST) to study uncertainty, following the idea that extropy is the dual concept of entropy. In this paper, we present their fractional versions named fractional Deng entropy and extropy and compare them to other measures in the framework of DST. Here, we study the maximum for both of them and give several examples. Finally, we analyze a problem of classification in pattern recognition in order to highlight the importance of these new measures. 相似文献
992.
A quantum similarity measure between two molecules is normally identified with the maximum value of the overlap of the corresponding molecular electron densities. The electron density overlap is a function of the mutual positioning of the compared molecules, requiring the measurement of similarity, a solution of a multiple-maxima problem. Collapsing the molecular electron densities into the nuclei provides the essential information toward a global maximization of the overlap similarity function, the maximization of which, in this limit case, appears to be related to the so-called assignment problem. Three levels of approach are then proposed for a global search scanning of the similarity function. In addition, atom—atom similarity Lorentzian potential functions are defined for a rapid completion of the function scanning. Performance is tested among these three levels of simplification and the Monte Carlo and simplex methods. Results reveal the present algorithms as accurate, rapid, and unbiased techniques for density-based molecular alignments. © 1997 by John Wiley & Sons, Inc. J Comput Chem 18: 826–846, 1997 相似文献
993.
着重阐述了铅的污染与对人体健康危害情况及应采取的预防措施。这些预防措施都是简单可行的,对于减少铅的污染,免受它的危害,增进人体健康都有十分重要意义。 相似文献
994.
B. Øksendal 《Applied Mathematics and Optimization》1999,40(3):355-375
We study an impulse control problem where the cost of interfering in a stochastic system with an impulse of size ζ∈
R is given by
c+λ|ζ|,
where c and λ are positive constants. We call λ the proportional cost coefficient and c the intervention cost . We find the value/cost function V
c
for this problem for each c>0 and we show that lim
c→ 0+
V
c
=W , where W is the value function for the corresponding singular stochastic control problem. Our main result is that
This illustrates that the introduction of an intervention cost c>0 , however small, into a system can have a big effect on the value function: the increase in the value function is in no proportion
to the increase in c (from c=0 ).
Accepted 23 April 1998 相似文献
995.
T. S. S. R. K. Rao 《Proceedings Mathematical Sciences》1999,109(3):309-315
In this note we consider the property of being constrained in the bidual, for the space of Bochner integrable functions. For
a Banach spaceX having the Radon-Nikodym property and constrained in its bidual and forY ⊂ X, under a natural assumption onY, we show thatL
1 (μ, X/Y) is constrained in its bidual andL
1 (μ, Y) is a proximinal subspace ofL
1(μ, X). As an application of these results, we show that, ifL
1(μ, X) admits generalized centers for finite sets and ifY ⊂ X is reflexive, thenL
1
μ, X/Y) also admits generalized centers for finite sets. 相似文献
996.
Wojciech Banaszczyk 《Random Structures and Algorithms》1998,12(4):351-360
Let ‖·‖ be the Euclidean norm on R n and γn the (standard) Gaussian measure on R n with density (2π)−n/2e. It is proved that there is a numerical constant c>0 with the following property: if K is an arbitrary convex body in R n with γn(K)≥1/2, then to each sequence u1,…,um∈ R n with ‖u1‖,…,‖um‖≤c there correspond signs ε1,…,εm=±1 such that ∑mi=1εiui∈K. This improves the well-known result obtained by Spencer [Trans. Amer. Math. Soc. 289 , 679–705 (1985)] for the n-dimensional cube. © 1998 John Wiley & Sons, Inc. Random Struct. Alg., 12: 351–360, 1998 相似文献
997.
This paper is concerned with the optimal control of jump-type stochastic differential equations associated with polar-decomposed
Lévy measures with the feature of explicit construction on the jump term. The concrete construction is then utilized for analysis
of two portfolio optimization problems for financial market models driven by stable-like processes.
相似文献
998.
LIU Dan ZHAO Xin LONG Gui-Lu 《理论物理通讯》2008,49(2):329-332
Four-qubit entanglement has been investigated using a recent proposed entanglement measure, multiple entropy measures (MEMS). We have performed optimization for the nine different families of states of four-qubit system. Some extremal entangled states have been found. 相似文献
999.
S.I.S.向量随机测度在弱拓扑及相容拓扑下的收敛性 总被引:1,自引:0,他引:1
本文主要研究s.i.s.向量随机测度在弱拓扑及相容拓扑下的收敛性,给出了s.i.s.向量随机测度在弱拓扑 容拓扑下的Vitali-Halm-Saks定理,作为应用,我们建立了R^1-值有界可测函数关于Banach空间值s.i.s.向量随机测度的随机积分的收敛定理,并得到了具typep的Banach空间中s.i.s.向量随机测度的大数定律及中心极限定理。 相似文献
1000.
Jan Thomsen Raymond E. Levitt John C. Kunz Clifford I. Nass Douglas B. Fridsma 《Computational & Mathematical Organization Theory》1999,5(4):385-401
Validation of complex simulation models is a challenging problem in computational organization theory research. In this paper, we describe a validation strategy suitable for emulation simulation systems, and show how a comprehensive validation consists of a sequence of steps that evaluate different aspects of a computational organizational simulation model. We demonstrate how this strategy can be applied to the evaluation of the Virtual Team Alliance (VTA), an emulation simulation system designed to guide managers charged with organizational change. VTA required a &201C;trajectory&201D; of successive validation experiments, before managers where willing to follow the recommendations of VTA. Ultimately, we believe this validation approach can be applied to a wide range of different simulation systems, and will make identification of the strengths and weaknesses of organizational simulations easier. 相似文献