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151.
Mauricio Chacón-Tirado 《Topology and its Applications》2010,157(18):2769-2777
In this paper we show that the space of selections of a smooth fan is a complete separable absolute retract. Then, we show that it is homeomorphic to the Hilbert space l2. 相似文献
152.
Rafael Lazimy 《Annals of Operations Research》2007,152(1):273-295
We extend the classic mean-variance framework to a broad class of investment decisions under risk where investors select optimal
portfolios of risky assets that include perfectly divisible as well as perfectly indivisible assets. We develop an algorithm
for solving the associated mixed-integer nonlinear program and report on the results of a computational study. We then study
the mean-variance structure of the investment frontier facing an individual investor in the presence of investment opportunities
in both risky divisible and indivisible assets. Finally, we analyze the economic implications of the presence of investment
opportunities in risky indivisible assets on the investor’s investment strategy and on his risk evaluation. 相似文献
153.
基于均值-VaR的投资组合最优化 总被引:13,自引:0,他引:13
利用均值-VaR方法,提出了有交易费用存在时的最优投资组合模型。通过求解均值-方差模型来研究均值-VaR模型的有效前沿,并指出在收益率的分布为正态分布的假设下,均值-VaR模型的有效集是均值-方差有效前沿的子集。有关全局最小VaR的存在性的分析显示在选择VaR的置信水平时必须非常小心。最后给出了应用均值-VaR模型的实例分析。 相似文献
154.
155.
塞曼调制磁旋转分子光谱特征的研究 总被引:1,自引:0,他引:1
夏长平 《原子与分子物理学报》1997,14(4):547-552
以N2第一正带(B3Πg-A3Σ+u)为对象,研究塞曼调制磁旋转光谱技术的主要特征,对谱线的线型和位相做了详细的分析,同时,还提出并解释了谱线强度分布中的塞曼选态效应,结果均与实验相符合。 相似文献
156.
Xin-hua Liu 《应用数学学报(英文版)》2005,21(4):693-696
It was shown in Xia that for incomplete markets with continuous assets' price processes and for complete markets the mean-variance portfolio selection can be viewed as expected utility maximization with non-negative marginal utility. In this paper we show that for discrete time incomplete markets this result is not true. 相似文献
157.
Summary Seven of the most popular methods for bandwidth selection in regression estimation are compared by means of a thorough simulation
study, when the local polynomial estimator is used and the observations are dependent. The study is completed with two plug-in
bandwidths for the generalized local polynomial estimator proposed by Vilar-Fernandez & Francisco-Fernández (2002). 相似文献
158.
ExistenceTheoremsofRandomNashEquilibriumPointsforRandomSet┐valuedMapsLuoQun(罗群)(DepartmentofMathematics,GuizhouNormalUniversi... 相似文献
159.
内容分发协议ShareStorm的Neighbor Selection机制 总被引:1,自引:1,他引:0
针对BitTorrent行为及其Neighbor Selection机制存在的缺陷,提出一种有效度量P2P内容分发协议的实验方法,并设计一种新的内容分发协议ShareStorm,该协议的Neighbor Selection机制充分考虑互联网拓扑和通讯成本,更倾向于与本地的peers建立邻居关系.经初步验证,在下载完成时间这个最主要的性能指标上,ShareStorm比BitTorrent至少减少50%. 相似文献
160.
《Particuology》2022
This paper presents a thorough study of particle impact breakage in selection function with a unified breakage criterion. The impact mode and breakage pattern for particulate materials are classified based on a significant review of well-established impact testers. It was found that the lack of a unified breakage criterion to determine the breakage probability disables a direct comparison of particle breakage propensity from different impact loading testers. The literature breakage models to describe the breakage probability are reviewed where the advantage and drawback of these models are scrutinized. The sourced literature breakage models are compared with the zeolite breakage datasets in a unified breakage criterion to evaluate the model performance. A novel computational modelling workflow for a milling process is proposed to provide a guidance in implementing the digital twin in milling process prediction. The breakage probability models, i.e. the selection functions are comprehensively assessed in population balance model to examine the model serviceability. The model simplicity and fidelity in the model assessment are specifically discussed and the value of digital twin in substantially reducing the experimental trials is highlighted. 相似文献