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171.
Wen-Shiung Lee Gwo-Hshiung Tzeng Jyh-Liang Guan Kuo-Ting Chien Juan-Ming Huang 《Expert systems with applications》2009,36(3):6421-6430
Basing on the Gordon model perspective and applying multiple criteria decision making (MCDM), this research explores the influential factors and relative weight of dividend, discount rate, and dividend growth rate. The purpose is to establish an investment decision model and provides investors with a reference/selection of stocks most suitable for investing effects to achieve the greatest returns. Taking full consideration of the interrelation effect among variables of the decision model, this paper introduced analytical network process (ANP) and examined leading electronics companies spanning the hottest sectors of lens, solar, and handset by experts. Empirical findings indicated that dividend was affected by industry outlook, earnings, operating cash flow, and dividend payout rate; discount rate was affected by market β and risk-free rate; and dividend growth rate was affected by earnings growth rate and dividend payout growth rate. Also, according to literatures, discount rate possessed a self-effect relationship. Among the eight evaluation criteria, market β was the most important factor influencing investment decisions, followed by dividend growth rate and risk-free rate. In stock evaluations, leadership companies in the solar industry outperformed those in handset and lens, becoming investors’ favorite stock group at the time that this research was conducted. 相似文献
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随着流媒体应用需求的日益增加,不断改进和完善现有流媒体系统性能势在必行,将云计算引入流媒体系统成为未来流媒体系统的一大趋势.本文简单分析了云计算、CDN(ContentDeliveryNetwork)St]P2P(PeertoPeer)网络的优缺点和研究现状.主要讨论并分析了云环境下的P2P流媒体传输系统所面临的带宽问题、流媒体数据处理、服务质量问题和系统中的关键技术——虚拟化技术、存储管理技术、调度技术和复制技术.此外,从搭建云计算实验环境角度。本文列举了目前比较流行的5种仿真实验手段. 相似文献
177.
Byung-Hyuk Lee Jong-Chun Park Moo-Hyun Kim Sung-Chul Hwang 《Computer Methods in Applied Mechanics and Engineering》2011,200(9-12):1113-1125
The violent free-surface motions and the corresponding impact loads are numerically simulated by using the Moving Particle Semi-implicit (MPS) method, which was originally proposed by Koshizuka and Oka [10] for incompressible flows. In the original MPS method, there were several defects including non-optimal source term, gradient and collision models, and search of free-surface particles, which led to less-accurate fluid motions and non-physical pressure fluctuations. In the present study, how those defects can be remedied is illustrated by step-by-step improvements in the respective processes of the revised MPS method. For illustration, two examples are studied; (i) dam breaking problem and (ii) liquid sloshing inside a rectangular tank. The improvement of each step is explained and numerically demonstrated. The numerical results are also compared against the experimental results of Martin and Moyce [12] for dam-breaking problem and Kishev et al. [9] for sloshing problem. The numerical results for violent free-surface motions and impact pressures are in good agreement with their experimental data. 相似文献
178.
This paper addresses a very important question—how to select the right products to promote in order to maximize promotional
benefit. We set up a framework to incorporate promotion decisions into the data-mining process, formulate the profit maximization
problem as an optimization problem, and propose a heuristic search solution to discover the right products to promote. Moreover,
we are able to get access to real supermarket data and apply our solution to help achieve higher profits. Our experimental
results on both synthetic data and real supermarket data demonstrate that our framework and method are highly effective and
can potentially bring huge profit gains to a marketing campaign. 相似文献
179.
When multimedia information is transported over a packet-switched network, the quality of presentation can be degraded due
to network delay variation or jitter. This paper presents a dejittering scheme that can be used in the transport of MPEG-4
and MPEG-2 video to absorb any introduced network jitter, thus preserving the presentation quality of transported media streams.
The dejittering scheme is based on the statistical approximation of delay variation in the arrival times of video packets
carrying encoded clock reference values and a filtering and re-stamping mechanism. In addition, a brief overview of the MPEG-4
system is presented. 相似文献
180.
This paper develops a framework for the consideration of internal markets as an alternative to information systems (IS) outsourcing. It is based on an assessment of the pros and cons of both outsourcing and of insourcing based on the internal markets approach. It is formulated in terms of the operational, tactical, and strategic impacts of the choice among the alternatives. The framework, and the propositions that are developed from it, should be useful both for researchers, who can use it for developing testable research hypotheses, and for practitioners, who may use it as a basis for developing a comprehensive set of criteria for the evaluation of these sourcing options. 相似文献