高考数学的一个新亮点——猜想题

猜想是对所要研究的问题依据已有材料、条件和知识，进行实验、观察、分析、比较、联想、类比、归纳、推理等，作出符合一定的经验与事实的推测性想象的思维方法．牛顿指出：“没有大胆的猜想，就做不出伟大的发现”。猜想是发现问题、解决问题的一种重要的思维方法，是创新思维的重要组成部分，猜想也是数学发展的动力，数学理论的重大突破往往起源于立意深邃的猜想，正是无数数学家们的猜想，数学科学才发展到当今的现代数学。由于猜想可让学生体验数学发现和创造的历程，培养和发展他们的创新思维和合情推理能力，更能体现高考的选拔功能，因此近几年猜想题倍受高考命题老师的亲睐，成为高考数学题的一个新亮点．本文试对这类题型及解法作一综述，供参考．     

静态球对称黑洞Dirac场的统计熵

利用改进的brickwall模型,给出了一类静态球对称黑洞Dirac场的熵,结果表明,在取相同的截断因子时,Dirac场的熵均为标量场的熵的72倍 关键词： 黑洞 统计熵 brickwall模型 Dirac场     

日本：新一代客机 速度超过2倍音速

日本航天局不久前首次对外表示，他们计划近日对其新一代超音速客机进行关键性试飞活动，其中主角正是其最新研制中的“箭型”超音速飞机。据悉，此次新型超音速飞机试飞将在澳洲大陆内陆实验场进行，根据此前的理论设计，在这次至关重要的试验过程中，“箭型”飞机将有望飞出两倍音速的最新飞行速度记录。对此日本方面希望，这种新型超音速飞机有望替代已经停飞的“协和式”式飞机，成为新一代全球飞的最快的超音速客机。     

Theoretical Research on a Kind of Quantum Left-handed Metamaterial

Recently, research on left-handed materials （LHMs） has attracted considerable attentions. The LHMs are a kind of metameterial which have negative permittivity and negative permeability, which lead to negative refractive index in a frequency range. The LHMs that have been available so far are in the microwave range and are usually composed of classical particles, such as split-ring resonators. Some quantum phenomena such as spontaneous emission of atoms in the LHMs which are considered to be ＇classical background＇ have also been investigated. Many potential applications of LHMs have been proposed, such as superlenses which, in principle, can achieve arbitrary subwavelength resolution.     

A Reliability Analysis of Calculated Results for Odd-Even and Odd-Odd Nuclei in Relativistic Mean-Field Theory

We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition, the result is explained theoretically.     

Advances in micro-perforated panel absorbers

Theoretical and experimental investigations on the performance of micro-perforated -panel absorbers are reviewed in this paper. By reviewing recent research work, this paper reveals a relationship between the maximum absorption coefficient and the limit of the absorption frequency bandwidth. It has been demonstrated that the absorption frequency bandwidth can be extended up to 3 or 4 octaves as the diameters of the micro-holes decrease. This has become possible with the development of the technologies for manufacturing micro-perforated panels, such as laser drilling, powder metallurgy, welded meshing and electro-etching to form micrometer order holes. In this paper, absorption characteristics of such absorbers in random fields and in high sound intensity are discussed both theoretically and experimentally. A new absorbing structure based on micro-perforated-panel absorbers demonstrate experimentally high sound absorption capability. This review shows that the micro-perforated-panel absorber has potentials to be one of ideal absorbing materials in the 21st century.     

组合期权交易策略的概率分析

在假定股票价格服从Ito过程条件下，讨论了采用组合期权交易策略的投资者获益的概率及损益的数学期望，得到了具体计算式，只要投资者获得相应数据，通过具体计算式加以计算，便可以为期权投资者提供数量上的重要参考依据，对期权投资者具有实用价值。     

论谭嗣同思想产生的社会基础和理论渊源

谭嗣同是戊戌维新派的杰出代表 ,是戊戌变法时为追求真理而勇敢牺牲的伟大的爱国者 ,同时也是中国近代史上比较有影响力的思想家。本文主要探讨谭嗣同思想产生的社会基础和理论渊源。     

谈高校学分制的学分管理

学分制又称学分积累制，是高等学校的一种教学管理制度。该文就学分制教学管理中经常涉及到的关于课程学分的认定、学分绩点与平均学分绩点的计算等学分管理问题作一些探讨。     

电磁场相对论变换的初等推导

给出了一种仅用偏微分就可导出电磁场相对论变换的方法，避免了四维矢量、张量等运算。同时，也非常直接地显示了电磁场相对论变换是电磁场规律相对论协变性的必然要求。