滞后序列分析视域下的高中化学高端备课师生互动行为研究*

为揭示“高端备课”项目下教师与学生行为互动的关键特征,研究采用视频分析法及滞后序列分析法(LSA)对2019年高端备课项目中“离子反应”课堂中的师生交互行为、比率、教师语言、师生操作技术以及教师与学生之间的交互行为等进行量化与质性分析。研究发现,高端备课更加关注学生对于本源性认识问题的科学认识逻辑,以传授核心观念建构以及基于学生认识发展为本为理念,由知识解析为本向促进学生认识发展转变,通过师生思维不断碰撞的过程促进学生知识迁移与应用,为常态化课堂优化提供了参考路径。     

用于连续抽样方案的两类更优的中止规则

本文提出并讨论了适用于各类连续抽样方案的两参数中止规则 [N ,c]和 [R ,d]。作为应用 ,以MIL STD 12 35B中公布的CSP V方案为例 ,计算并给出了相应的中止参数 ,还将 [N ,c],[R ,d]与已有的两类规则 [S],[R]进行了特性比较。结果表明 ,[N ,c]和 [R ,d]均具有更优的统计特性     

CONSTANT ELASTICITY OF VARIANCE MODEL AND ANALYTICAL STRATEGIES FOR ANNUITY CONTRACTS

The constant elasticity of variance（CEV） model was constructed to study a defined contribution pension plan where benefits were paid by annuity. It also presents the process that the Legendre transform and dual theory can be applied to find an optimal investment policy during a participant＇s whole life in the pension plan. Finally, two explicit solutions to exponential utility function in the two different periods （before and after retirement） are revealed. Hence, the optimal investment strategies in the two periods are obtained.     

Optimal investment strategy for annuity contracts under the constant elasticity of variance (CEV) model

This paper focuses on the constant elasticity of variance (CEV) model for studying the optimal investment strategy before and after retirement in a defined contribution pension plan where benefits are paid under the form of annuities; annuities are supposed to be guaranteed during a certain fixed period of time. Using Legendre transform, dual theory and variable change technique, we derive the explicit solutions for the power and exponential utility functions in two different periods (before and after retirement). Each solution contains a modified factor which reflects an investor’s decision to hedge the volatility risk. In order to investigate the influence of the modified factor on the optimal strategy, we analyze the property of the modified factor. The results show that the dynamic behavior of the modified factor for the power utility mainly depends on the time and the investor’s risk aversion coefficient, whereas it only depends on the time in the exponential case.     

原子核裂变的发现：历史与教训——纪念原子核裂变现象发现60周年

回顾了原子核裂变发现走过的一段弯路，讨论了这段历史提供的启发和教训．     

A general repeat inspection plan for dependent multicharacteristic critical components

A component is critical if it causes disaster or a very high cost upon failure. Multicharacteristic critical components exist in many systems. Such components could be a part of an aircraft, space shuttle, a special weapon system or a gas ignition system. In many situations, characteristics’ failures of these components are statistically dependent. In this paper, a new inspection plan for such components is proposed. A mathematical model that depicts the plan is developed and an example demonstrating the results of the model is given. The advantage of this model over the other model where independence of the characteristics’ failure is assumed for the case of dependency is illustrated. The model resulted in an average of 32.4% reduction in cost compared to the situation where the dependency case is solved assuming statistical independence.     

带有中止检查规则（n－i）的CSP－1方案

本文引人转移概率母函数及幂级数等方法讨论带有中止规则（ｎ＊－ｉ）的连续抽样方案ＣＳＰ－１的中止概率Ｐ＊得到了Ｐ＊作为ＣＳＰ－１方案的度量的理论特性，证明了Ｄｏｄｇｅ型ＣＳＰ－１方案与带有中止规则（ｎ＊－ｉ）的ＣＳＰ－１方案具有相同的ＡＯＱ，ＡＦＩ，ＯＣ函数．文末还给出了一些数值结果．     

Bayesian Sampling Plans for Exponential Distribution Based on Type I Censoring Data

We study variable sampling plans for the exponential distribution based on type I censoring data. Using a suitable loss function, a Bayesian variable sampling plan (n _B , t _B , _B ) is derived. For certain prior distributions and loss functions, the numerical values of the Bayesian sampling plans and the associated minimum Bayes risks are tabulated. In terms of Bayes risks, comparisons between the proposed Bayesian sampling plans (n _B , t _B , _B ) and the Bayesian variable sampling plans (n ₀, t ₀, ^L _{T 0}) of Lam (1994, Ann. Statist., 22, 696–711) have been made. The numerical results indicate that under the same conditions, the proposed Bayesian sampling plan is superior to that of Lam in the sense that the Bayes risk of (n _B , t _B , _B ) is less than that of (n ₀, t ₀, ^L _{T 0}).     

基于贝叶斯网络的船舶污染事故应急预案完备性评估

根据船舶污染事故应急预案涉及的事件和事件之间的逻辑关系构架了应急预案的故障树结构, 将故障树结构贝叶斯网络化, 构建了标准贝叶斯网络图, 由此建立一种船舶污染事故应急预案完备性评估的新方法. 利用该方法对市级船舶污染事故应急预案的缺失事件进行了分析, 评估了预案的完备度, 并与其他评估方法进行比较, 验证了该方法有效.     

A Kind of the ASN' Extreme Value forMeasuring Double Sampling Plan

ＡＫｉｎｄｏｆｔｈｅＡＳＮ＇ＥｘｔｒｅｍｅＶａｌｕｅｆｏｒＭｅａｓｕｒｉｎｇＤｏｕｂｌｅＳａｍｐｌｉｎｇＰｌａｎ￥ＨａｎＺｈｉｌｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈ．ＭｅｃｈａｎｉｃｓＺｈｅｎｇｚｈｏｕＩｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎｏｌｏｇｙ）...