X-ray Diffractions of Deformation Structure in Polycrystalline Fe-32Mn-5Si Alloy

The change of microstructure with strain was investigated in a Fe-32Mn-5Si austenitic alloy at room temperature by X-ray diffraction profile analysis. The experimental results show that the Fe-32Mn-5Si alloy is deformed by the strain-induced γ→ε transformation and the twinning except dislocation slip at room temperature. The amount of strain-induced ε-martensite, the stacking fault probability and the twinning probability all exhibit parabolic relationship with increasing strain. The stacking fault probability is higher than the twinning probability.     

The fixation probability of beneficial mutations

The fixation probability, the probability that the frequency of a particular allele in a population will ultimately reach unity, is one of the cornerstones of population genetics. In this review, we give a brief historical overview of mathematical approaches used to estimate the fixation probability of beneficial alleles. We then focus on more recent work that has relaxed some of the key assumptions in these early papers, providing estimates that have wider applicability to both natural and laboratory settings. In the final section, we address the possibility of future work that might bridge the gap between theoretical results to date and results that might realistically be applied to the experimental evolution of microbial populations. Our aim is to highlight the concrete, testable predictions that have arisen from the theoretical literature, with the intention of further motivating the invaluable interplay between theory and experiment.     

部分信息下相邻2-out-of-n:F系统的可靠性分析

对相邻2-out-of-n系统可靠性的研究大都假定部件的失效时间分布是已知的,即部件的可靠度是已知的,然而该假设在许多情况下是不合理的(例如软件系统,人机系统)。本文针对部件的失效时间分布未知,仅仅具有关于部件可靠度的部分信息情况,也就是我们仅仅知道部件的寿命在某些重叠区间的可靠度,利用不精确概率理论分析了该系统,获得了相邻2-out-of-n:F环形与线形系统可靠度上下界的精确公式。最后用例子说明了本文的方法,并指出了在该方向上需要进一步研究解决的问题。     

概率有限自动机的商和同态

本文主要是通过概率有限自动机的有效划分来研究概率有限自动机的同态与商概率有限自动机的相关问题,得到了在同态或同构(弱同构)意义下概率有限自动机相互之间的关系,以及它们的商概率有限自动机的相互关系,得到了一些有意义的结果.     

常利率下的更新风险模型

讨论了常利率下的更新风险模型，证明了索赔时刻Tk的资产余额Uδ（Tk)(k≥0)构成一个齐次马尔科夫链，且给出其转移概率Q（x,B)。利用转移概率得到了风险问题中的几个重要的量和分布；破产概率，破产时余额分布以及破产前瞬间余额分布的级数展开式和积分主程。     

探雷声呐水雷发现概率仿真研究

以探雷声呐对目标的累积探测概率计算模型为主要研究对象。以累积探测概率的研究作为效能分析的基础,针对发现概率定义不准确的问题对它提出了新的定义,从而更好地实现对某次搜索过程中探雷声呐发现目标能力大小的仿真计算。通过对探雷声呐工作原理和工作过程的分析研究,将连续多次探测到目标定义为发现目标一次的声呐操作过程与离散的(λ,σ)过程模型相结合,在经典模型理论的基础上提出了适用于探雷声呐的累积探测概率计算模型。仿真结果表明,该计算模型实现了对探雷声呐发现目标能力大小的量化分析,为探雷声呐的作战使用与指挥决策提供了理论依据。     

基于改进自适应遗传算法的钢框架非线性优化设计

遗传算法在建筑钢结构设计中的应用不仅改变了传统的设计概念,而且可以丰富钢结构优化设计理论和方法,在经济建设中取得显著效益．在比较、分析、综合现有的一些改进方法的基础上,对基本遗传算法提出了一系列改进措施,形成了一种高效综合的遗传算法．改进算法采用最优保存策略和比例选择相结合的选择思路,设计了与进化代数相关的交叉概率和与个体适应度相关的变异概率．将该算法应用于以质量（造价）最小为优化目标的钢框架结构的优化设计中,结果表明,改进的遗传算法不仅可以获得满意的优化效果,而且还有效地提高了计算速度.     

光电积累检测原理和发现概率及虚警概率的测试方法

本文从理论上分别研究噪声和信号加噪声通过选频电路的统计特性,根据两者的差别,提出了抑制噪声的抗干扰电路。叙述积累检测原理及检测电路,并从理论上分析积累检测对检测性能的贡献,进而介绍光电检测中发现概率和虚警概率的测试方法。     

构件粘接强度分类判别二类错误率的计算及应用

本文提出了一种构件粘接强度分类判别中二类错误率的计算方法,其中关于误差函数的计算机算法具有通用性,它可以代替正态分布概率计算的查表方法。     

A New Technology for Synthesizing Signals with Preset Probability Characteristics

New physical and mathematical definitions are proposed for the one-dimensional probability density in the stationary random process differentiable in the mean square. Prospects for using the formulas are discussed. An experimental confirmation is given of the possibility of analyzing signal compositions and synthesizing signals with given probability characteristics. __________ Translated from Izmeritel'naya Tekhnika, No. 7, pp. 17–19, July, 2005.     

The MMI-check program

A program is described for identifying probability distributions for measured and calculated quantities from the data for repeated measurements. __________ Translated from Izmeritel’naya Tekhnika, No. 7, pp. 20–21, July, 2006.     

平行钢索的锈蚀时变失效概率分析

在综合锈蚀开始时间的概率模型和锈蚀面积扩展的概率模型的基础上,建立了平行拉索锈蚀时变失效概率模型。根据不同检测周期钢丝锈蚀概率树形结构的特点,提出了锈蚀概率计算的分枝约界方法,有效地解决了计算量指数级增长的问题。模型参数分析和拉索失效概率算例表明:在模型参数统计评估正确性的前提下,该模型能够预测在役拉索任何检修周期的钢丝锈蚀的数目及其概率,能够计算任意时刻钢丝锈蚀的总量,进而分析拉索的时变失效概率。该模型的提出是对拉索锈蚀失效问题的一种探索研究,对拉索检测评估研究具有一定的参考价值。     

统计公差·优质产品·经济效益

 以数理统计方法论证了传统尺寸公差的局限性,分析了限定统计公差对确保配合性质和质量,制造优质产品,从而获得最佳经济效益的理论与方法。     

大型舰艇系统破损失效概率计算

对于大型舰船，多次命中和结构防护成为破损失效概率计算的主要问题，该文通过对各种算法的比较和研究，综合了逻辑代数法、网格积分法和蒙特卡罗随机模拟法的优点，较好地解决了这些问题，得到了满意的计算结果。     

Two-Parameter Observation of Correlated Poisson Signals in Poisson Noise

Computer simulation is used to derive the probabilities of errors involving overlooking the signal and false alarm as governed by the correlation coefficient between channels for two-parameter signal observation.Translated from Izmeritel’naya Tekhnika, No. 3, pp. 9–11, March, 2005.     

一种改进的广义概率数据关联跟踪算法

对于多目标跟踪问题,最近提出的全局次优的广义概率数据关联算法(GPDA)由于其新颖的可行性划分规则和较小计算存储需求而受到广泛关注。本文提出了一种基于广义联合事件分割组合的新关联算法。它通过引入目标的方向性信息,在基于新规则划分后,对进入有效域的传感器量测估计值权重系数进行调整,从而使最终的估计值更准确,关联精度得到进一步提高。利用该改进算法对杂波环境下多目标跟踪进行仿真实验,结果表明提出的关联算法继承了原有算法的优点,同时用较小的计算代价使得跟踪性能得到较大改善。     

New super-kurtic probability density function for use in computer simulation

The philosophy of computer simulation and its application to hydrological processes is described in this paper. The structure of natural hydrologic time processes is indicated and the techniques to filter out white noise is explained. The limitations of the well-known probability density functions (PDF) such as the Gaussian, Pearson’s and Johnson’s etc. in hydrologic applications are set forth. A new super-kurtic PDF developed by the author specially for hydrological processes is introduced and a numerical example is given.     

Simple distribution-free statistical assessment of structural integrity material property data

The assessment of structural integrity data requires a statistical assessment. However, most statistical analysis methods make some assumption regarding the underlying distribution. Here, a new distribution-free statistical assessment method based on a combination of Rank and Bimodal probability estimates is presented and shown to result in consistent estimates of different probability quantiles. The method is applicable for any data set expressed as a function of two parameters. Data for more than two parameters can always be expressed as different subsets varying only two parameters. In principle, this makes the method applicable to the analysis of more complex data sets. The strength in the statistical analysis method presented lies in the objectiveness of the result. There is no need to make any subjective assumptions regarding the underlying distribution, or of the relationship between the parameters considered.     

Indeterminateness of the results of calibrating measuring instruments in the narrow and the broad sense

The use of the Handbook on the Expression of Indeterminateness in Measurements in the solution of measurement problems involved in calibration of measuring instruments. __________ Translated from Izmeritel’naya Tekhnika, No. 9, pp. 15–20, September, 2007.     

基于装备损伤概率的舰艇动力系统安全性分析

考虑舰艇损害管制过程中人员因素对系统的影响，运用马尔科夫链对人员操作引起的舰艇动力系统损伤概率进行修正，根据修正后的毁伤概率，建立概率危险性评估模型，引入危险度指标，对动力系统在遭受武器攻击情况下的危险度进行了计算，并依据计算结果对系统安全度进行评定。