模糊马尔科夫链状预测模型及其工程应用

针对工程问题的特点结合马尔科夫链理论 ,提出了具备状态模糊划分和具有“大体无后效性”特点的模糊马尔科夫链状的预测模型。并给出了模糊马尔科夫链的初始概率和一重转移概率的计算方法的一般公式。发展了马尔科夫链预测方法 ,拓宽了其应用范围     

K-T条件在对偶问题中的应用

将非线性规划中的一个重要理论K-T条件和线性规划中的对偶问题结合起来,并在具体应用的基础上给出了一个简单且易操作的求解线性规划最优解的方法。     

Size effect on the optimum actuation condition for SMA-composites

Techniques of using shape memory alloy (SMA) wires as actuators inside the hybrid composites have been studied extensively for improving mechanical properties of structures. There were many experimental findings and theoretical predictions agreed the higher the actuation temperature on built-in SMA wires, the greater the improvement in mechanical response of a composite due to recovery action of wires. However, due to the limitation of interfacial shear strength, over-actuation (by means of electrical resistive heating) of SMA wire is able to induce the development of interfacial crack inside the composite structure. When the maximum interfacial shear strength is attained due to vigorous recovery action of SMA wire under relatively high temperature, interfacial debond can be initiated. In this paper, a typical SMA–matrix cylinder model is employed to study the captioned risk of SMA-composite actuation. Applying the criterion of optimum actuation condition (OAC), target actuation level can be determined to prevent structural failure due to over-actuation. Effects of geometric factors including wire embedded length and matrix-to-wire radius ratio on the interfacial shear stress distribution are evaluated prior to the study of size effect on OAC. Results indicate that the size effect become negligible when these two geometric factors are sufficiently large and as a result, the governing equation of OAC can be greatly reduced to a simple relation between externally applied stress and actuation temperature on the SMA wire. This simplified model is able to enhance the application of OAC and provide a simple and explicit solution to determine an ideal range of actuation levels for a large scale SMA-composite structure in the design stage.     

Perturbation method of the piezoelectric fracture mechanics considering the permittivity of the medium in the crack gap

In this paper, the problem of the cracks with arbitrary forms in piezoelectric material is studied. The permittivity of the medium in the crack gap is considered. Except the collinear cracks, this boundary condition is too difficult to deal with; therefore, a perturbation method is recommended. By the way, the electric boundary conditions of electric fracture mechanics are discussed. For example, a small parameter solution of a crack is given and compared with the known `exact' (it will be discussed later) solution. This result shows that the impermeable or permeable conditions are only the boundary conditions for the first approximations of the perturbation solutions.     

断路器在线机械状态的信息处理

介绍了一种断路器机械状态在线监测与诊断的方法。通过分析同步采集到的振动信号、线圈电流以及断路器的分、合信号,可提取其特征信息量(即指纹信息),并据此对断路器的机械状态作出判断。     

发电设备状态检修平台总体方案的研究与探讨

针对国内大多数火力发电厂设备检修的现状,详述了状态检修的概念,并针对电厂设备提出了一套完整的状态检修平台的设计方案,采用模块化结构的设计思想,平台界面友好、使用方便,为电厂实现真正意义上的状态检修提供一种可行性方案。     

气体-颗粒两相流动力学及其在气溶胶采样中的应用

大气颗粒物切割器的工作原理主要是重力沉降、离心分离和冲击分离,是气体-颗粒物两相流的动力学分离过程.气固两相流动力学方程可以较方便地用来分析大气颗粒物在切割器中的运动轨迹,具体计算过程中阻力系数CD和边界条件应根据具体情况分析选定.本文给出了两个利用数值计算模拟切割器工作的例子,对采样仪的采样效率、切割粒径及切割器结构尺寸等设计参数对切割粒径的影响进行计算,表明两相流动力学是对采样切割器中颗粒物的运动进行数值模拟的有效工具,能对采样仪、切割器的设计、制造提供有力的帮助.     

降低高炉槽下返矿率的生产实践

本文分析了槽下返矿率高的原因及其不利影响。烧结厂通过加强各方面的管理和进行设备技术改造，使槽下返矿率明显下降，取得了明显的效果和经济效益。     

Mood-Induced Increases in Alcohol Expectancy Strength in Internally Motivated Drinkers.

This study investigated whether exposure to musical mood induction procedures (MMIP) differentially increases the strength of specific alcohol expectancies for coping motivated (CM) versus enhancement motivated (EM) drinkers. Participants were 86 undergraduates who had elevated scores on either the CM or EM subscale of the Drinking Motives Questionnaire (M. L. Cooper, 1994). Participants were randomly assigned to either a positive or negative mood condition. The Alcohol Craving Questionnaire (E. G. Singleton, S. T. Tiffany, & J. E. Henningfield, 1994) was administered at baseline and after MMIP to assess phasic changes in alcohol expectancy strength. Consistent with hypotheses, only CM drinkers in the negative mood condition reported increased relief expectancies, and only EM drinkers in the positive mood condition reported increased reward expectancies. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于小波分析的医学超声图像去噪与增强研究

去除超声斑点噪声,增强图像以提高图像质量是医学图像处理的重要课题。论文提出基于小波分析的超声图像去噪与增强方法。首先是结合自适应方向加权中值滤波和小波半_软阈值去噪法有效抑制了斑点噪声,保留必要的细节;然后采用基于小波变换高频增强法增强图像并用同态增晰法增强对比度,有效地改善图像的质量;最后从去噪图像和评价指标上与常用斑点去噪法进行了比较。实验表明,该方法优于其他方法,具有实际的应用价值。