古典概率的问题解决与创新

在古典概率问题的计算过程中,适当选取样本空间、利用概率的对称性及数形结合使问题的求解变得简单而又直观。     

古典概率的教学与思考

本文针对古典概率是高职院校工程数学的重要组成部分,结合自身教学经历,总结如何组织古典概率教学以增强堂教学效果,以及在概率课程中培养学生思维能力,达到素质教育的目的。     

An improved R-tree based on childnode＇s probability

R-Tree is a good structure for spatial searching. But in this indexing structure, either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

关于古典概率计算中样本空间的构造

如何构造样本空间才能使问题的解决比较简捷，这是一个非常值得探讨的问题。本文结合具体典型例子，给出了在正确思路的前提下，古典概率计算中样本空间构造的一般原则及最佳样本空间的构思。     

古典概型中样本空间的选取

求解古典概型的习题大多是求解某个随机事件Ａ的概率，一般包含两步：一是选取适当的样本空间，二是计算样本总数ｎ和事件的有利场合数ｍ。而选取适当的样本空间对求古典概型中事件概率具有重要意义。     

关于古典概率计算中样本空间的构造及优化

构造适当的样本空间可使古典概率的计算简捷.文中给出了在正确思路的前提下,古典概率计算中样本空间构造的一般原则及最佳样本空间的构思.     

古典概型中随机事件相互独立的充要条件

在古典概型和概率空间(Ω,(F),P)[1]上,讨论随机事件相互独立的充要条件.证明概率空间(Ω,(F),P)上随机事件相互独立的充要条件是随机事件可表示成不同轴条事件.     

优化样本空间 简解古典概型

通过对称压缩法、样本空间缩小法、事件对等转化法三种方法优化了样本空间,简化了古典概型的计算.     

古典概型典型思考方法探讨

在概率论学习中首先接触的古典概型,历来都是教学中的重点.通过部分典型问题探讨一些解古典概型问题的思考方法,有助于概率论基本概念的直观理解,并且有益于开启概率论课程的学习.     

Generalization and refinement of Hermite-Hadamard＇s inequality

利用Hermite-Hadamard不等式和Jensen不等式,得到两个序列,给出Hermite-Hadamard不等式的一个推广和加细.     

对“中奖免费”的定量剖析

本文用古典概率的方法对“中奖免费”推销产品的社会现象进行了定量分析,指出了对日常生活中的小概率事件,既要大胆面对,又要谨慎处理的科学建议。     

Improvement of Laih and Yen＇s multisignature scheme

A new attack is proposed to show that a specified group of verifiers can cooperate to forge the signature for any message by secret key substitution due to the leaked secret key or by the group public key adjustment because of the renewed members. This paper presents the improvement scheme which overcomes the security weakness of Laih and Yen‘s scheme.     

Least Privileges and Role＇s Inheritance of RBAC

The main advantages of role-based access control （RBAC） are able to support the well-known security principles and roles＇inheritance. But for there remains a lack of specific definition and the necessary formalization for RBAC, it is hard to realize RBAC in practical work. Our contribution here is to formalize the main relations of RBAC and take first step to propose concepts of action closure and deta closure of a role, based on which we got the specification and algorithm for the least privileges of a role. We propose that roles＇ inheritance should consist of inheritance of actions and inheritance of data, and then we got the inheritance of privileges among roles, which can also be supported by existing exploit tools.     

古典概型中随机事件相互独立性与素数的关系

本文在古典概型和概率空间(Ω,F,P)[1]上, 讨论随机事件相互独立与素数的关系.利用古典概型概率计算方法,证明概率空间(Ω,F,P)恰有n个相互独立的随机事件的充要条件是样本空间Ω的样本点个数可以分解成n个素数的乘积.     

Women＇s Image of Nurturers in Anderson＇s Stories

Women＇s image of nurturers is successfully portrayed in Sherwood Anderson＇s stories.Anderson places hopes on women for two reasons：Women retain nurturing impulses which benefit men,and with their tenderness,understanding and love they can comfort the frustrated,defeated men;Women are less defeated by modern life and with their wisdom and ability to deal with the realities of life,they may help men out of their impotence and frustration.This paper gives a detailed analysis of the female characters＇image of nurturers in these stories.     

Tsinghua＇s Institute of Biomedicine and MIT＇s McGovern Institute for Brain Research Sign Collaboration Agreement

Tsinghua＇s Institute of Biomedicine and Massachusetts Institute of Technology＇s McGovern Institute for Brain Research on January 14, 2008, signed a collaboration agreement to further enhance joint brain research efforts. To better know the secret of human thinking has always been a goal for scientists. In recent years especially, the development of various neural imaging technologies and neural information processing techniques has enabled researchers to overcome limitations and to explore more deeply neural functions. As a result, a complete research system, from the cellular level to the behavioral level was established. Major contributions to this research system were made by molecular, cellular, computational neuroscience, and cognitive neuroscience. Tsinghua University sponsors significant research in the area of brain studies.     

浅谈概率题的几种特殊解法

本文针对职业高中数学的概率实际应用的广泛性,通过举例子来说明常见概率题型的几种特殊解法:一、避开排列组合求概率;二、对称性在概率中的应用;三、数列在概率中的应用。     

古典概型问题教学探讨

《概率统计》是师专数学专业的一门必修专业课,概率论是在古典概型的基础上发展起来的,古典概型在概率论中占有相当重要的地位。本文结合笔者多年的教学实践对古典概型问题的教学谈谈自己的几点做法和体会。