Minimizing the expected time to detect a randomly located lost target using 3-dimensional search technique

Abstract

This paper considers a new model in search theory to find a randomly located target in the 3-dimensional space. An approximation algorithm that facilitates searching procedures for searchers or robots is presented. The expected time to detect the target is also proved. The statistical analysis by calculating the optimal search strategy which minimizes the time to detect the target, assuming trivariate standard normal distribution is provided, and the technique by flowcharts is designed as well. The effectiveness of this strategy is illustrated by introducing an application from real world.     

从福斯特的《印度之行》看隔阂与分离

人类自身之间即种族之间、个体的朋友之间、母子之间甚至夫妻、情人之间都存在着难以理解的隔阂与分离;不可知的自然及其造物也极力阻止人类的联结与统一,因而与人类之间存在着隔阂与分离。此外,不同宗教的不同信仰使得各宗教群体的人们互不理解,产生隔阂与分离。所有这些都说明福斯特理想中人类真诚关系建立的艰难及人类联结与统一的艰巨性。     

Subset selection of superior populations when the number of populations is large

The situation where k populations are partitioned into one inferior group and one superior group is considered. The statistical problem is to select a random size subset of superior populations while trying to avoid including any inferior populations. A selection procedure is assumed to satisfy the condition that the probability of selecting at least one superior population is bounded below by P¹<1. The performance of a procedure is measured by the probability of including an inferior population.The asymptotic performance, as k→∞ of Gupta's traditional maximum type procedure ψ^G is considered in the location-model. For normally distributed populations, ψ^G turns out to be asymptotically optimal, provided the size of the inferior group does not become infinitely larger than the size of the superior group.     

陕北农村学校体育现状及发展对策研究

农村学校尤其是陕北,由于经费紧张等诸多因素,学校的体育设施和师资队伍的匮乏已成为制约农村学校体育发展的“瓶颈“.通过对陕北部分农村学校的调查、分析,探索解决这一问题的有效对策,试图为陕北农村学校体育改革和发展提供点借鉴.     

G.E.摩尔伦理学思想的两重性

G.E.摩尔作为现代西方元伦理学（分析伦理学）的开创者，其伦理思想具有两重性。在其理论体系中，既有成为主体和核心的分析伦理学，又有丰富的规范伦理学内容；而且还具有目的与手段的两重性。摩尔思想的这些方面对我们具有重要的借鉴意义。     

数字化高灵敏度荧光显微镜在As_2O_3诱导MGC-803细胞核凋亡产生钙振荡研究中的应用

利用数字化高灵敏度荧光显微镜对As2O3诱导MGC-803细胞核凋亡过程中的钙振荡进行研究,通过图像中荧光强度随时间变化的规律反应钙振荡的频率和强度变化。结果证实As2O3诱导MGC-803细胞核凋亡过程中,的确引发了钙振荡,说明核钙参与了凋亡过程,并且钙振荡的频率以低频为主。对两相邻细胞核的钙振荡信号观察分析发现,两核钙强度变化曲线低频部分异常相似,几乎在同一时刻达到最高点和最低点。尽管钙波动的幅度不同,但基本频率相同,由此可初步预测钙信号以频率变化为表达特征。两细胞核凋亡呈同步化趋势,证明在受到As2O3刺激后,细胞核的凋亡不是个别现象。     

Back-to-back mixtures of discrete distributions

A method for expanding the choices for fits of discrete data is given. The method is very simple: a breakpoint is chosen for the data set on either side of which two separate discrete distributions are fit. Thus, the method is a mixture of two discrete distributions. The method is appealing in light of the ease with which the likelihood equations simplify. For illustrative purposes, the method is used on the data set that motivated its conception.     

藏语白色颜色词的文化内涵

藏民族在审美心理中把“白色”视为洁净、诚挚、正直、高尚、忠诚、磊落品德的象征和寄托，体现了藏民族独特的思维方式和文化模式。     

学校体育教与学的关系研究

学校体育教学中教与学的关系是一种复杂的关系体系,文章从社会学视角对中小学体育教学中的教与学进行了研究,其目的是深入认识体育教学活动中教与学的关系及预防师生矛盾的发生,转变传统的教学观念,促进教师与学生的交流与合作,建立一种良性互动的、新型的师生关系,从而提高教学质量.     

Corporate support mechanisms for families: An exploratory study and agenda for research and evaluation

Based on telephone interviews with representatives from 16 corporations in the Baltimore-Washington area, this article explores the awareness of corporate officers of the linkages between work and family systems, their perceived responsibility for implementing policies and services that lend support to the family circumstances of employees, and the types of actions they had initiated in their corporations to help employees better balance work and family demands. Study results demonstrate limited awareness among corporate officers toward the work and family interface, employer uncertainty about corporate responsibilities for the family situation and demands of employees, and limited corporate development of family-oriented policies and services. These results are discussed in the context of recent federal initiatives to encourage greater corporate response to the family circumstances of employees. Implications are suggested for further research and evaluation.