疲劳裂纹扩展试验裂纹图像采集系统

针对目前金属疲劳裂纹扩展检测方法存在效率低、操作繁琐、精度不高，不能实现实时性等缺点，文章提出了基 于机器视觉的裂纹检测方法。根据金属疲劳裂纹扩展试验过程中裂纹图像的采集要求，设计了摄像头位置可自动调整 的疲劳裂纹图像采集系统，包括摄像头安装运动装置，裂纹图像采集装置以及摄像头运动控制系统。图像采集装置由高 分辨率黑白面阵CCD摄像头、光学镜头，光源照明装置和图像采集卡组成，前3者安装在摄像头支架上，与摄像头运动 装置相连。摄像头运动装置中的X，Y，，Z轴运动机构由步进电机带动滚珠导轨机构。在基于ARM技术的运动控制系统 的控制下摄像头可沿X，Y，，Z轴作高精度直线运动，实现和试件之间精确位置的调整。实验结果表明，所设计的系统可 采集到疲劳裂纹扩展试验过程中高清晰度、高分辨率的试件裂纹图像，满足下一步裂绞尺寸计算的要求；摄像头运动定 位精度可达到0. 02 mm，满足精确的系统聚焦、位置调整、跟踪采集的要求。     

Some remarks on the physical models concerning two different approaches to inference in statistical process control

Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.     

钛合金电子束焊接接头疲劳试验数据统计分析

本文利用国际焊接学会推荐的统计方法，对BT20钛合金电子束焊接接头焊态和焊后电子束局部热处理两种试样的疲劳试验结果进行了统计处理与分析．结果表明：对于BT20钛合金母材和电子束对接接头可以按铝合金参考FAT80级S—N曲线进行疲劳设计．建议在对BT20薄板进行电子束焊接和电子束局部热处理时应采取必要措施，以保证将焊接变形控制到最小程度，从而提高其疲劳强度．     

A log-Birnbaum–Saunders regression model with asymmetric errors

This paper introduces a skewed log-Birnbaum–Saunders regression model based on the skewed sinh-normal distribution proposed by Leiva et al. [A skewed sinh-normal distribution and its properties and application to air pollution, Comm. Statist. Theory Methods 39 (2010), pp. 426–443]. Some influence methods, such as the local influence and generalized leverage, are presented. Additionally, we derived the normal curvatures of local influence under some perturbation schemes. An empirical application to a real data set is presented in order to illustrate the usefulness of the proposed model.     

Racial battle fatigue and activist burnout in racial justice activists of color at predominately White colleges and universities

Activist burnout scholarship has inadequately considered challenges marginalized-identity activists, such as racial justice activists of color, experience in the course of their activism – challenges from which privileged identity activists, such as white racial justice activists, are protected. This article attempts to address this gap through a phenomenological study examining activist burnout in racial justice activists of color whose primary sites of activism are predominantly white colleges and universities in the United States at which they work. In order to stretch activist burnout theory to differentiate unique marginalized-identity activists’ burnout causes from general causes that do not consider specific activist identities, the lens of racial battle fatigue is employed. Findings show that, although participants shared many causes of burnout that are consistent with general non-identity-specific causes described in existing literature, racial battle fatigue hastened their burnout while their activist commitments elevated their battle fatigue.     

Professional quality of life of adult protective service workers

Adult Protective Services (APS) workers are exposed to substantial occupational hazards and job stress, but these stressors are underdocumented. Therefore, we sought to describe APS workers’ work environments and responses to occupational hazards and stressors, including compassion fatigue, burnout, and secondary traumatic stress. Survey data were gathered with closed-ended questionnaires administered to APS workers in an urban setting. Virtually all workers (97%) reported exposure to one or more environmental hazards in their work, and 80% reported hazard exposure in the past month. Workers also reported mixed responses to their work environment and to experiences with supervision. A sizable minority (22.7%) was at high risk for burnout, 24.6% were at risk for secondary traumatic stress, and 19.9% reported low compassion satisfaction. The results document multiple stressors in APS work. The APS partner is committed to ongoing efforts to better support its staff, and these findings can inform future efforts to enhance supervisor support and worker self-care, to minimize burnout and secondary traumatic stress.     

What do we call post-apartheid?

In this paper, the author examines the different uses and meanings of the usual expression “post-apartheid.” It has been used extensively in the social sciences, political discourse and the media since the mid-1980s. But what does it refer to, and has it always meant the same thing over the last 20 years? To answer that question, the author reviews the different ways she has used the notion in her research into workers’ forms of thinking and political subjectivities in South Africa since 1996. She distinguishes between its use as a chronological marker, an academic concept open to various problematics and epistemological decisions and a notion used by interviewees under various acceptations. She concentrates more specifically on the sequential implications of the adverb “post” in her work and argues that there have been political sequences in what she (with others) has named “post-apartheid.” She concludes that she intends to stop using this term in order to concentrate on identifying the current political sequence in South Africa.     

欧洲主权债务危机与欧元的前景

由美国次贷危机引发的全球性金融危机对欧洲大陆的冲击使欧洲长期积累的财政和债务问题逐步转变为主权债务危机。欧债危机的持续发酵主要是由欧元区内货币政策与财政政策脱节、高社会福利与低经济增长矛盾以及危机爆发后救助迟缓、乏力等因素导致的,同时它也是欧元区在建立之初就一直存在的严重的结构性缺陷所带来危害的集中体现。欧债危机对欧元区的稳定造成了极大冲击,给欧元未来的命运蒙上了一层阴影。欧元区未来的结局可能是促使欧债危机国家退出欧元区,而这对欧洲一体化进程则是沉重的打击。     

Association of Personal Distress With Burnout,Compassion Fatigue,and Compassion Satisfaction Among Clinical Social Workers

ABSTRACT

Studies of empathy and empathy-related responding show that while some people respond to observing the suffering of another with a prosocial concern and urge to help the suffering person, others have an aversive, avoidant response that is primarily self-focused and aimed toward relieving their own distress rather than helping the other person. This self-focused response, labeled personal distress, is associated with various social and psychological problems. This article discusses the concept of personal distress and describes a study of licensed clinical social workers (n = 171) that examines the relationship of personal distress and three other aspects of the empathy construct with compassion fatigue, burnout, and compassion satisfaction. Results of ordinary least squares multiple regression analyses indicate that the model of empathy components and control variables explain 20% to 23% of the variance in the dependent variables. Personal distress is the only component of the empathy construct with significant associations with the dependent variables. Higher personal distress is associated with higher compassion fatigue and burnout and lower compassion satisfaction among clinical social workers. Implications for future research and for social work education are discussed.     

文艺无定法

文艺无定法是文艺创造的一条基本原则，它具体表现在模仿生活、表现情感、刺激感官、躲避审美疲劳、追撵时代等方面。文艺无定法已经成为文艺保持生命活．力，获得大众接受的根本原因之一。