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41.
高温防窜水泥浆体系的研究及应用   总被引:1,自引:0,他引:1  
高温高压油气井的窜槽问题一直是困扰各油田固井的一大难题,尤其是高温高压长封固段井的油气窜槽问题更难以解决.高温防窜水泥浆体系具有优异的防窜性能及稳定性,稠化时间易调,低温条件下强度能较好地发展,采用多凝水泥浆方案可更好地解决高温高压长封固段油气井的固井质量问题.  相似文献   
42.
本文提出了在资源管理系统中基于作业检查点实现自动容错支持,深入分析了作业与任务检查点分离、映像文件管理、自动恢复执行等关键技术。基于BLCR在SLURM中实现了作业的自动检查点/恢复,详细介绍了实现中的关键技术难题。分析与测试表明,检查点与恢复执行功能正确,并能有效缩短大规模作业成功运行所需的时间。  相似文献   
43.
本文提出了解决最小完工时间的无等待流水调度问题的基于禁忌搜索的混合算法。算法结合了调度规则和禁忌搜索算法的优点,首先利用调度规则构造较好的初始解,既可以加快禁忌搜索算法的收敛速度,也可以降低整个算法的运算量,使算法有更好的工程实用性;然后使用变邻域结构的禁忌搜索算法改进当前解。在保持可达性的基础上,该算法缩小了邻域规模和减少了计算时间。数值仿真实验表明,该算法是有效的。  相似文献   
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This reply to Kobak’s (see record 2009-12106-002) comments on my article (see record 2009-12106-001) on dogs as attachment figures addresses three issues in defining and assessing features of attachment figures. These include whether some features are more critical than other features, different ways of assessing safe haven as a critical feature of an attachment figure, and whether attachment hierarchies are necessary to identify figures who fulfill the feature of safe haven. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
为了ARGO物理用户可以方便高效地在网格环境下完成大批量的ARGO数据处理作业的提交和管理,论文采用了数据库技术和封装技术,设计和实现了ARGO网格作业管理系统.该系统已经成功地完成在ARGO实验网格上的ARGO重建和模拟作业提交测试,初步验证了系统的可行性.  相似文献   
47.
Although negotiation experiences can affect a negotiator's ensuing attitudes and behavior, little is known about their long-term consequences. Using a longitudinal survey design, the authors tested the degree to which economic and subjective value achieved in job offer negotiations predicts employees' subsequent job attitudes and intentions concerning turnover. Results indicate that subjective value predicts greater compensation satisfaction and job satisfaction and lower turnover intention measured 1 year later. Surprisingly, the economic outcomes that negotiators achieved had no apparent effects on these factors. Implications, limitations, and future directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
The authors investigated the direct and interactive effects of the job demand– control–support (JDC-S) model’s components on subsequent changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides (TRI) separately for male and female employees. In contrast to all 14 past studies on these relationships, the authors used a longitudinal design. Study participants (N = 1,137, 66% men) were all apparently healthy employees who underwent a routine health check at 2 points in time (Time 1 and Time 2) about 22 months apart. In these analyses, the authors controlled for the Time 1 level of each criterion and for other confounders. Most of the direct and moderating effects found did not support the predictions of the JDC-S model; this finding is in agreement with the majority of past cross-sectional studies. The authors did not find any evidence supporting the existence of a reverse causation for either of the components of the JDC-S model. The authors suggest that serum lipids may not be a physiological mechanism mediating the effects of the JDC-S model on atherosclerotic diseases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
The present study examined whether job control moderated the association between stress indicators (distress and sleeping problems) and intentions to change profession among 2,650 Finnish physicians. Ordinal logistic regression analysis was applied. The authors found that high levels of distress and sleeping problems were associated with higher levels of intentions to change profession, whereas high job control was associated with lower levels of intentions to change profession even after adjusting for the effects of gender, age, and employment sector. In addition, high job control was able to mitigate the positive association that distress and sleeping problems had with intentions to change profession. Our findings highlight the importance of offering more job control to physicians to prevent unnecessary physician turnover. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
This article addresses the relation between day-specific experiences of job stressors and the pursuit of off-job activities. Following the limited-resources model of self-regulation, the authors proposed that job stressors and long working hours are negatively related to pursuit of sport activities after work because, after stressful days, employees have no resources left for initiating and persisting in effortful behaviors such as sport. Routines for off-job activities were hypothesized to be positively related to the pursuit of sport activities after work. Seventy-eight police employees completed a daily survey over 5 working days and indicated that they perceive sport to be highly useful for recovery. Random coefficient modeling showed that job stressors (particularly situational constraints) encountered on a specific day were negatively related to self-regulatory resources and to the amount of time spent on sport activities after work, whereas the relation with low-effort activities was positive. Thus, after a stressful day when an effective recovery activity such as sport is highly needed, persons tend to engage less in such an activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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