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。     

Coping with racial battle fatigue: differences and similarities for African American and Mexican American college students

Student of Color often reference racial microaggressions when asked to describe their post-secondary experience. The racial battle fatigue framework assists in understanding the cumulative, negative effect of racial microaggressions on psychological, behavioral, and physiological outcomes. This paper assesses the racial battle fatigue framework for African American and Mexican American college students and the impact of coping on racial stress. Results demonstrate that racial microaggressions negatively impact stress responses for African American and Mexican Americans differently, but coping may help alleviate the impact of racial battle fatigue. Universities can address racial microaggressions and negative health outcomes by educating campus constituents about racial microaggressions, addressing Whiteness, and providing education about adaptive coping strategies.     

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.     

对运动性疲劳恢复的研究

结合运动训练及比赛的实践,运用生理学和运动医学等理论,采用文献研究法,论述了现代竟技运动的特征、疲劳恢复的理论基础,提出了运动性疲劳产生的原因、部位、诊断及恢复方法,以便为广大教练员、运动员对疲劳与恢复问题进行研究提供参考.     

关于高周疲劳损伤演化方程的讨论

首先,指出Lemaitre等提出的高周疲劳损伤演化方程只适用于等效应力循环为等幅的加载情形.然后,基于等效应力循环为不等幅的加载情形,推导出适用于高周疲劳的损伤演化方程,说明上述等幅加载情形的损伤演化方程只是高周疲劳损伤演化方程的一个特例,且后者的结果更具一般性.     

车载高压天然气钢瓶的结构优化

文章对34CrMo4钢质车载天然气气瓶进行了水压爆破试验和水压疲劳试验,运用有限元软件ANSYS分析了气瓶的爆破压力与疲劳寿命。并通过ANSYS的优化模块对气瓶进行了结构优化设计。分析结果表明文中的计算方法准确,可作为工程上CNG气瓶结构设计时的参考方法。     

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.     

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。     

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。     

Is there a relationship between burnout and objective performance? A critical review of 16 studies

Previous research has suggested that high levels of burnout lead to impaired functioning on the job. However, as this research has usually relied on self-reported performance, it is imperative to examine whether this association is also confirmed when using “objective” performance data (e.g., supervisor reports). This study reviewed previous research on the associations between burnout (exhaustion, depersonalization, and personal accomplishment) and various types of objective performance. A systematic literature search identified 16 studies dealing with the burnout-performance relationship. These studies showed the wide variety of approaches that are used to study burnout and objective performance. Using data from these 16 studies, a meta-analysis was conducted to obtain mean correlations. The meta-analytical correlations between exhaustion and in-role behaviour (based on five studies), organizational citizenship behaviour (OCB; five studies), and customer satisfaction (two studies) were -.22, -.19, and -.55, respectively, underlining the practical relevance of burnout research for organizational performance. The evidence for the relationships between depersonalization, personal accomplishment, and performance was inconclusive. Future research should focus on valid indicators of job performance, should more often employ longitudinal designs and large samples, and should consider the theoretical basis for the study expectations more extensively.