Ruin Probability with Variable Premium Rate and Disturbed by Diffusion in a Markovian Environment

We consider a risk model with a premium rate which varies with the level of free reserves. In this model, the occurrence of claims is described by a Cox process with Markov intensity process, and the influence of stochastic factors is considered by adding a diffusion process. The integro-differential equation for the ruin probability is derived by a infinitesimal method.     

现代科学的复杂性审视--齐曼科学社会学思想的新发展

约翰·齐曼是一位科学家出身的科学社会学家。他认为现代科学正在从学院时代走向了后学院时代,因此其传统的学术规范即默顿规范随之也要作出相应的修正;科学进步也像生物进化,有自然选择但也有自组织能力;科学虽然并不具有绝对可靠性,但它仍然有理由值得我们去信赖。     

1998年至2003年山西省科技进步统计分析

通过山西省5年期间科技进步统计检测指标位次，进一步分析了科技进步统计监测体系的四个一级指标。     

电子碰撞Ag的L壳层电离截面的测量

作者用Si(Li)探测器测量了能量为5～2keV的电子碰撞Ag的L壳总平均电离截面；用Monte Carlo方法计算的电子反射能谱，修正了来自衬底的反射电子对测量结果的影响．作者对实验结果与Cryzinski的理论计算结果进了比较．     

国内橡胶助剂研究开发情况及发展趋势

全面介绍了我国橡胶助剂的品种、性能、生产厂家等，根据现状对今后橡胶助剂工业的发展提出了预测和建议。     

Newton's Easy Quadratures ``Omitted for the Sake of Brevity'

In the 1687 Principia, Newton gave a solution to the direct problem (given the orbit and center of force, find the central force) for a conic-section with a focal center of force (answer: a reciprocal square force) and for a spiral orbit with a polar center of force (answer: a reciprocal cube force). He did not, however, give solutions for the two corresponding inverse problems (given the force and center of force, find the orbit). He gave a cryptic solution to the inverse problem of a reciprocal cube force, but offered no solution for the reciprocal square force. Some take this omission as an indication that Newton could not solve the reciprocal square, for, they ask, why else would he not select this important problem? Others claim that ``it is child's play' for him, as evidenced by his 1671 catalogue of quadratures (tables of integrals). The answer to that question is obscured for all who attempt to work through Newton's published solution of the reciprocal cube force because it is done in the synthetic geometric style of the 1687 Principia rather than in the analytic algebraic style that Newton employed until 1671. In response to a request from David Gregory in 1694, however, Newton produced an analytic version of the body of the proof, but one which still had a geometric conclusion. Newton's charge is to find both ``the orbit' and ``the time in orbit.' In the determination of the dependence of the time on orbital position, t(r), Newton evaluated an integral of the form ∫dx/x <sup>n</sup> to calculate a finite algebraic equation for the area swept out as a function of the radius, but he did not write out the analytic expression for time t = t(r), even though he knew that the time t is proportional to that area. In the determination of the orbit, θ (r), Newton obtained an integral of the form ∫dx/√(1−x<sup>2</sup>) for the area that is proportional to the angle θ, an integral he had shown in his 1669 On Analysis by Infinite Equations to be equal to the arcsin(x). Since the solution must therefore contain a transcendental function, he knew that a finite algebraic solution for θ=θ(r) did not exist for ``the orbit' as it had for ``the time in orbit.' In contrast to these two solutions for the inverse cube force, however, it is not possible in the inverse square solution to generate a finite algebraic expression for either ``the orbit' or ``the time in orbit.' In fact, in Lemma 28, Newton offers a demonstration that the area of an ellipse cannot be given by a finite equation. I claim that the limitation of Lemma 28 forces Newton to reject the inverse square force as an example and to choose instead the reciprocal cube force as his example in Proposition 41. (Received August 14, 2002) Published online March 26, 2003 Communicated by G. Smith     

2003版建筑给排水规范学习与设计体会

就新规范中住宅给水管管径、引入管阀门设置、水箱进水管和溢水管设置、水箱水位控制、通气管系统设计及地漏的设置等方面谈了作者学习《建筑给水排水设计规范》(GB50015-2003)的体会。     

基于校园网络的远程教育系统方案设计

本文分析了大理学院跨校区的远程教育系统实施方案,设计了一套技术先进、性能可靠、标准开放、扩展灵活的远程教育系统。     

超高灵敏显色反应测定痕量锑──锑（Ⅲ）─罗丹明B─碘化钾体系

本文研究结果表明，水溶性大分子化合物阿拉伯胶和非离子表面活性剂ＴｒｉｔｏｎＸ－１００共同存在下，锑碘配阴离子和罗丹明Ｂ的显色反应具有很高的灵敏度。缔合物的最大吸收在５ｇ０ｎｍ，摩尔吸光系数ε＝６．１×１０￣５Ｌ·ｍｏｌ－１·ｃｍ－１。用巯基棉富集锑，分离干扰离子。本法可应用于有色金属中痕量锑的测定。     

STABILITY CRITERIA FOR A CLASS OF UNCERTAINSYSTEMS WITH TIME—DELAY

Some stability criteria are obtained for a class of uncertain systems with time-delay usingLyapunov functional and analytic techniques. It is easy to check the criteria by making use of theboundedness of the uncertainties.