巧用两只弹簧的组合 加深对简谐振动的理解

如果放在光滑桌面上的物体只受一只弹簧的作用，那么物体所作的运动是简揩运动．简谐运动是一种最简单的基本运动，它的动力学特点是物体所受合力满足F=-kx，该力叫回复力．简谐运动的特点是具有周期性，周期T=2π√m/k，其中m是振动物体质量，k是回复力     

利用直线y=x模型研究递推数列问题

著名数学家华罗庚先生说过:“数缺形时少直观,形少数时难入微,数形结合百般好,隔裂分家万事休.”本文就是利用形象的直线“y=x”模型来研究某些递推数列问题,不仅使这一类问题的解决简捷明快,而且更具有直观性和启发性.1递推数列在某已知图象上例1(2005年辽宁高考题)一给定函数     

原子物理学的学术战略地位与素质教育中的作用

探讨了原子物理学在现代科学技术中的学术战略地位以及素质教育中的重要作用，指出了在科教兴国、大力发展高科技的今天，原子物理学的教学只能加强、不能削弱。     

单光子态的产生与测量

报道了通过自发参量下转换产生单光子态的实验研究,使用中心波长425 nm的飞秒脉冲泵浦Ⅰ类非共线相位匹配的BBO晶体,在实验上得到单光子计数率为2.978×10-4,并分析了实验中的相关问题.     

合作联盟资源集成计划一种新方法

合作联盟里，资源集成计划往往是联盟成员群体谈判博弈的结果。本以两人博弈为例，对联盟的资源集成计划给出一个谈判博弈模型，能够较好地模仿和反映合作联盟资源整合计划的制订过程。     

稀疏过程在破产问题中的应用

本讨论一类人寿保险的风险过程，其中保单到达服从齐次Poisson过程。而描述退保及索赔发生的计数过程分别为这一过程的q-稀疏与p-稀疏．对此模型给出其破产概率的具体上界，并与其它一类风险模型进行比较．     

Theoretical analysis of the acoustical characteristics of suspended micro-perforated panel absorbers

Sound absorption characteristics of suspended micro-perforated panel absorbers were investigated theoretically. The method of half thickness model of such panel absorber with quadripole analysis was used for predicting its acoustic performance. The analysis results show that the predictions agree well with the measurements of absorption in the reverberation chamber. The factors affecting the absorption characteristics for such absorbers were discussed, and some rules as design guidelines were given.     

基于MMD算法的HMM参数重估计的矩阵表示

本文提出的MMD算法用于提高模型区别错误信息和正确信息的能力．利用该算法在对模型的参数进行重估计时．涉及到复杂的目标函数的梯度运算．击运用矩阵运算使得梯度运算变得简单明了，因此本文给出了MMD算法下的HMM参数重估计的矩阵表示形式并给出了证明．     

Spectral property and its shape transition on ^72-84Kr isotopes in microscopic core plus two-quasiparticle approach

By using a microscopic sdIBM-2 2q.p, approach, the levels of the ground-band, 7-band and partial two-quasi-particle bands for ^72-84Kr isotopes are calculated. The data obtained are in good agreement with the recent experimental results, and successfully reproduce the nuclear shape phase transition of ^72-S4Kr isotopes at zero temperature.The ground-state band is described successfully up to J^π=18^ and Ex=10.0MeV. Based on this model, the aligned requisite minimum energy has been deduced. The theoretical calculations indicate that no distinct change of nuclear states is caused by the abruptly broken pair of a boson, and predict that the first backbending of Kr isotopes may be the result of aligning of two quasi-neutrons in orbit g9/2, which galus the new experimental support of the measurements of g factors in the ^78-86Kr isotopes.     

Local Lyapunov Exponent for the Bak-Sneppen Model

The chaotic Property of the Bak-Sneppen model is studied from the local Lyapunov exponent in the same way as for dynamical nonlinear systems.Similar behaviour is found for the one- and two-dimensional Bak-Sneppen models.The Lyapunov exponents for the two cases have the same order of magnitude and both decrease at early evolution but show a slow increasing saturation at late evolution.