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111.
This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment. 相似文献
112.
李萍 《黄河科技大学学报》2003,5(2):124-126
网络时代,高校师生的学习方式和生活方式发生了深刻变化。互联网在促进教育发展和人才培养的同时,对学生的消极影响不容忽视。要多方面加强思想政治工作,如开辟网上“思想政治教育课堂”、设置“网上德育阵地”、建立信息监控等。 相似文献
113.
114.
研究了一种基于神经网络的心电图分类方法,该方法利用前向多层神经网络的反向传播算法(Back Propagation),即BP算法,采用MATLAB软件建立用于三分类的BP神经网络,并利用大量的心电图数据训练神经网络,使神经网络对未训练过的心电图有较好的分类能力。实验结果表明,用这种方法用于心电图的三分类取得较好的效果。 相似文献
115.
The performance of speaker verification systems is often compromised under real-world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a novel method to overcome this problem by using a non-linear handset mapper. Under this method, a mapper is constructed by training an elliptical basis function network using distorted speech features as inputs and the corresponding clean features as the desired outputs. During feature recuperation, clean features are recovered by feeding the distorted features to the feature mapper. The recovered features are then presented to a speaker model as if they were derived from clean speech. Experimental evaluations based on 258 speakers of the TIMIT and NTIMIT corpuses suggest that the feature mappers improve the verification performance remarkably. 相似文献
116.
李敏 《孝感职业技术学院学报》2007,10(4):89-92
文章针对采用二层规划模型描述的固定需求条件下的连续平衡网络设计问题,给出了一种基于间隙函数的求解算法。同时给出了一个简单的算例来说明该算法的可行性。 相似文献
117.
陈英杰 《三门峡职业技术学院学报》2007,6(3):1-4
本文从世界高等教育发展史、我国高等职业教育发展史和我国学位制度的演变说明高等职业教育是一种类型,并对今后我国职业教育的发展从认识上、制度上、具体办学上相应提出了建议。 相似文献
118.
Limeng Liang 《International Journal of Disability, Development & Education》2016,63(3):369-383
This article reports on a mixed-method inquiry into pre-service and in-service secondary school teachers’ knowledge about Attention-deficit Hyperactivity Disorder (ADHD) and attitudes toward students with this disorder in Hong Kong. The inquiry revealed no differences between pre-service and in-service secondary school teachers concerning their knowledge of ADHD and attitudes toward students with ADHD. It also identified possible sources of participants’ knowledge and a variety of factors underlying their attitudes toward students with ADHD including sociocultural beliefs and working conditions. The findings call for teacher educators to develop better education programmes to support both pre-service and in-service teachers in undertaking the challenging task of teaching students with ADHD. 相似文献
119.
随着Internet和多媒体技术的发展,网络教学逐渐兴起。Agent作为一种软件代理工具,在网络教学智能化方面可发挥更灵活、更多样化的作用。 相似文献
120.
Robert W. Bell 《PRIMUS》2017,27(3):406-417
AbstractMentoring undergraduate students in research is both rewarding and challenging. In this paper we present how we established a summer Research Experience for Undergraduates (REU) program in the mathematical sciences at Michigan State University. A goal of our REU is to include students who are at an early stage of their study of mathematics. We share our experiences in recruiting students, designing research projects, and mentoring our participants. We discuss the challenges we faced and the solutions we found while working with a diverse group of undergraduate students from across the nation. 相似文献