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901.
针对NPD项目复杂性各因素间具有的关联性以及传统评价方法的局限性,提出一种基于关联多属性的2-可加模糊测度方法来对NPD项目复杂性进行评价。在界定项目复杂性内涵的基础上,从产品复杂性、环境复杂性、组织复杂性和技术复杂性四个方面构建了NPD项目复杂性评价指标体系。从模糊测度、默比乌斯变换和交互作用系数间的转化关系出发,基于最大Marichal熵原则,提出了一种确定2-可加模糊测度值的新方法。利用Choquet积分作为集结算子,自下而上计算各候选方案的综合评价值。最后,通过具体算例说明了该方法的可行性和有效性。 相似文献
902.
对160名农村苗族学龄前儿童进行了膳食营养状况调查,并分组补充微维营养素进行营养干预试验。结果表明,苗族学龄膳食儿童热能及蛋白质基本达到RDA,但钙、核黄素、维生素A缺乏明显,膳食结构不合理,贫血发生率高,补充微量元素和维生素对儿童贫血有明显改善作用。提出了几项促进学龄儿童营养健康的建议措施。 相似文献
903.
M. Piraveenan M. Prokopenko A. Y. Zomaya 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):291-300
We analyze Shannon information of scale-free networks in terms of their assortativeness, and identify classes of networks
according to the dependency of the joint remaining degree distribution on the assortativeness. We conjecture that these classes
comprise minimalistic and maximalistic networks in terms of Shannon information. For the studied classes, the information
is shown to depend non-linearly on the absolute value of the assortativeness, with the dominant term of the relationship being
a power-law. We exemplify this dependency using a range of real-world networks. Optimization of scale-free networks according
to information they contain depends on the landscape of parameters’ search-space, and we identify two regions of interest:
a slope region and a stability region. In the slope region, there is more freedom to generate and evaluate candidate networks
since the information content can be changed easily by modifying only the assortativeness, while even a small change in the
power-law’s scaling exponent brings a reward in a higher rate of information change. This feature may explain why the exponents
of real-world scale-free networks are within a certain range, defined by the slope and stability regions. 相似文献
904.
Generation of Greenberger-Horne-Zeilinger states for multiple atoms trapped in separated cavities 总被引:1,自引:0,他引:1
S. B. Zheng 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):719-722
We propose a scheme for generating maximally entangled states for multiple atoms trapped in distant cavities connected by
fibers. During the operation neither the atomic system nor the fibers are excited, which is important in view of decoherence.
Under certain conditions, the probability that the cavities are excited is negligible. The scheme does not include projective
measurement and the GHZ state is generated deterministically. Taking advantage of adiabatic passage, the entanglement fidelity
is insensitive to fluctuation of experimental parameters. 相似文献
905.
In this paper we propose a multi-criteria decision making support system, called a “Feedback Based Diagnosis System” (FBDS), to aid the marketing team of an e-commerce (EC) organisation in its activities. The FBDS database is composed of customers’ satisfaction measures. These measures are related to the different services an EC offers to its customers. Thus, they constitute a multi-criteria (MC) evaluation of EC performances. In the general framework of recommender systems, these available MC evaluations are considered as useful information for other customers to help them to objectively, rationally and exhaustively assess and compare the numerous ECs among the ones likely to meet their needs. Our FBDS is not concerned with improving or automating such a recommendation process for customers. Indeed, it is merely EC management team oriented. In fact, the MC feedback database is used to diagnose the EC health and improve its strategy. In the proposed FBDS, a possibilistic framework is combined with the multi criteria representation to capture the variability and the divergence of customers’ evaluations w.r.t. each criterion. Then, an aggregation based on a weighted arithmetic mean (WAM) is proposed to obtain a synthetic appraisal of ECs. The WAM aggregation models the strategy agreed on by the EC management team. Computing the synthesis score of an EC consists in propagating the uncertainty related to its partial scores through the WAM. The possibilistic representation guarantees that no information is lost in the collective evaluation process by the consumers’ community. However, diagnosis indicators are finally proposed to the marketing team to make the interpretation of some possibilistic results more comprehensive when necessary. 相似文献
906.
JunPing Li 《中国科学A辑(英文版)》2009,52(5):875-894
We consider the decay parameter, invariant measures/vectors and quasi-stationary dis- tributions for 2-type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2 \ 0. It is shown that this λC can be directly ... 相似文献
907.
A nonnegative form on a complex linear space is decomposed with respect to another nonnegative form : it has a Lebesgue decomposition into an almost dominated form and a singular form. The part which is almost dominated is the largest form majorized by which is almost dominated by . The construction of the Lebesgue decomposition only involves notions from the complex linear space. An important ingredient in the construction is the new concept of the parallel sum of forms. By means of Hilbert space techniques the almost dominated and the singular parts are identified with the regular and a singular parts of the form. This decomposition addresses a problem posed by B. Simon. The Lebesgue decomposition of a pair of finite measures corresponds to the present decomposition of the forms which are induced by the measures. T. Ando's decomposition of a nonnegative bounded linear operator in a Hilbert space with respect to another nonnegative bounded linear operator is a consequence. It is shown that the decomposition of positive definite kernels involving families of forms also belongs to the present context. The Lebesgue decomposition is an example of a Lebesgue type decomposition, i.e., any decomposition into an almost dominated and a singular part. There is a necessary and sufficient condition for a Lebesgue type decomposition to be unique. This condition is inspired by the work of Ando concerning uniqueness questions. 相似文献
908.
Surjit Singh Khurana 《Journal of Mathematical Analysis and Applications》2009,350(1):290-293
Let X be a completely regular Hausdorff space, E Hausdorff a quasi-complete locally convex space and Cb(X,E) all E-valued bounded continuous functions on X with strict topologies βt, , . We prove that a linear continuous mapping T:Cb(X,E)→E arises from a scalar measure μ∈(Cb′(X),βz)(z=t,∞,τ) if and only if g(T(f))=0 whenever g○f=0 for any f∈Cb(X,E), g∈E′. 相似文献
909.
Under the assumption that μ is a non-doubling measure on Rd, the authors obtain some estimates for the maximal multilinear commutators generated by Calderón-Zygmund operator T and RBMO(μ) functions associated to this measures. 相似文献
910.
We investigate the minimal Riesz s-energy problem for positive measures on the d-dimensional unit sphere Sd in the presence of an external field induced by a point charge, and more generally by a line charge. The model interaction is that of Riesz potentials |x−y|−s with d−2?s<d. For a given axis-supported external field, the support and the density of the corresponding extremal measure on Sd is determined. The special case s=d−2 yields interesting phenomena, which we investigate in detail. A weak∗ asymptotic analysis is provided as s→+(d−2). 相似文献