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41.
为实现桥梁施工精度的准确控制,保证桥梁施工质量符合设计要求,对某多跨连续-刚构桥梁的施工控制进行了计算分析。首先,通过理论计算桥梁的预拱度,并在施工过程中采取相应的高程及应力控制措施;其次,通过现场实测,对施工过程中的高程及应力进行实时监测,将监测值与控制值进行比较,以评价控制效果。实例检验结果表明:在高程控制方面,最终合龙高程误差不超过8mm,满足了桥梁的线型要求;在应力控制方面,主梁和墩身应力均为压应力,且远小于规范限值,满足设计要求。因此,在桥梁施工过程中,通过理论计算与施工控制相结合的方法,能够实现桥梁高程及应力的有效控制,达到预期效果。桥梁施工控制措施的有效性在研究中得到了验证,可为类似桥梁施工提供参考。  相似文献   
42.
The job stress and coping behavior of female employees has become a key issue in the hospitality industry. This study investigates the moderating role of regulatory leisure coping styles on the effect of job stress on female employees’ well-being. Specifically, this study extends Patry et al.’s (2007) findings to further confirm the direct and moderating role of regulatory leisure coping styles in the relationship between job stress and well-being. Data were collected from the female employees of 22 tourist hotels in Taiwan. The results showed that the Planned-Breather Leisure Coping Style (PBLCS) was positively and significantly associated with well-being, whereas the Avoidant Leisure Coping Style (ALCS) had a negative and significant effect on it. In addition, the results also revealed that the PBLCS plays a buffering role, but that the ALCS plays an amplifying role. Based on these findings, the implications and research suggestions are then discussed.  相似文献   
43.
土石混合体边坡地质灾害是中国最为常见的地质灾害之一,而降雨是其主要诱发因素,降雨条件下边坡劣化机理研究是防灾减灾领域的重要研究方向.通过分析不同含水率条件下土石混合体力学性质试验数据,建立抗剪强度参数随含水率的演化方程;以此为基础,针对西南地区典型土石混合体边坡,考虑降雨条件下力学参数弱化的影响,采用Geostudio软件开展边坡稳定性分析.结果表明:演化方程能有效反映含水率增大对土石混合体抗剪强度具有显著的弱化效应;降雨强度的增大会显著降低边坡稳定性,降雨持时只是降雨过程中某一时刻值的体现,对边坡稳定性影响不大;降雨量与边坡安全系数呈明显线性负相关.研究成果可为土石混合体边坡地质灾害预测与防治提供技术支撑.  相似文献   
44.
Abstract

Objective:

The objective of this study was to compare clinician and patient measures of satisfaction with two pharmacological stress agents (PSA), regadenoson and dipyridamole, used in Single Photon Emission Computed Tomography (SPECT) Myocardial Perfusion Imaging (MPI).

Methods:

This observational study included patients who had undergone SPECT MPI with regadenoson or dipyridamole, as well as the clinician/clinical technologist who performed the test. Mean scores for individual item and domain scores of the main outcome measures were computed as well as the effect sizes (ES) of the mean difference in scores between treatment groups. Statistical significance of the mean item and domain score differences were assessed via Mann-Whitney tests.

Main outcomes measures:

Two self-report questionnaires which had beeb previously developed and validated: Patient Satisfaction/Preference Questionnaire (PSPQ) and Clinician Satisfaction/Preference Questionnaire (CSPQ).

Results:

A total of 87 patients (68 received regadenoson, 19 received dipyridamole) and nine clinicians/clinical technologists took part in the study. Patients had a mean age of 66.8?±?12.2 years, and 56.3% were male. Compared to dipyridamole, use of regadenoson was associated with greater clinician satisfaction on all items and domains of the CSPQ (p?<?0.001 for all comparisons). Among patients, regadenoson was associated with less bother and greater satisfaction than dipyridamole for all items on the PSPQ. These patients reported less stinging at the injection site (ES?=??0.66) and less nervousness during injection (ES?=??0.60). The PSPQ found that regadenoson patients were more satisfied with their PSA than dipyridamole patients in all areas.

Limitations:

This study utilized a relatively small sample size of dipyridamole patients and lacked an adenosine group. A broader sampling of professionals would also help demonstrate generalizability.

Conclusion:

Both patients and clinicians reported higher satisfaction with regadenoson compared to dipyridamole for SPECT-MPI. Clinicians were particularly satisfied with the preparation and administration aspects of the drug, while patients rated it highly on convenience and reduced incidence of side-effects.  相似文献   
45.
大学生初步担任足球裁判员,面临较大的心理压力,这种心理压力产生的外在因素有来自比赛球员、教练员、观众、天气状况、场地等因素的压力;内在因素有业务水平、体能、职业道德、思想动机气质与性格等因素的压力.过大的心理压力不得于大学生做好足球执法工作,就当通过提高理论水平、实践能力、心理素质和身体素质,以消除大学生足球裁判员的心...  相似文献   
46.
The stress suppressing model proposes that sufficient resources reduce stress. The stress exposure model suggests that certain factors expose individuals to more stress. The current study tested these two models by assessing the within-person lagging effect of leisure time on perceived severity of daily stressors. Analyzing eight-day diary data (N=2,022), we found that having more leisure time than usual on a day reduced perceived severity of daily stressors the next day and that the decrease in severity became larger with further increase in leisure time. Additionally, the effect is much stronger among busy individuals who usually had little leisure time. The findings demonstrated an accelerated suppressing effect that differed between-person, and the lagging effect affords stronger implication for causality than correlational analysis.  相似文献   
47.
接触问题是一种典型的边界条件非线性问题。在分析接触问题时,使用Abaqus/standard模块,能正确模拟接触的过程,判断接触状态、输出接触压力。通过对圆柱滚子轴承在Pro/E中建立三维模型,然后导入ABAQUS软件进行接触分析,得出滚子与内、外圈之间接触应力的分布情况,和理论分析能很好地吻合,对轴承的选型具有指导意义。  相似文献   
48.
The complex and changing environment of the hospitality industry presents a never ending array of stimuli, pressures and demands which can become sources of stress for hotel supervisors. A focus on the identification of current and potential stressors in organizations, and the development of strategies which individuals and management may use to manage and reduce stress effectively, is imperative. This study is to investigate the perceived level of stress of hotel supervisors, to establish frequency of the use of various coping strategies, and to determine the burnout rate. This study also empirically examines the relationships among stress, coping strategies, and job burnout. A convenient sample of hotel supervisors of large hotels in Taiwan was selected. The return of 298 questionnaires represented 74.5% of the total supervisors surveyed. The study findings suggest that the major job stress of hotel supervisors originates from task characteristic and workload. Moreover, a direct action coping strategy may allow one to perceive the situations as opportunities and may, in turn, contribute to reduce job stress. Furthermore, hotel supervisors experience a lower level of burnout if they apply more direct action strategies in coping with the pressures of their job. The results of this study can be used as part of guidelines including what should be considered to reduce job stress and burnout in the work environment.  相似文献   
49.
This article addresses the issue of measuring the level of aggregate financial stress on stock markets, which is a central issue for investors and policy-makers. To this end, Realized EquiCorrelation (REC) is obtained by plugging realized volatility as an input into the Dynamic EquiCorrelation (DECO) model where both the continuous and jump components of realized volatility are considered. An application is provided for the 20 major stock markets over January 2000–May 2014 using intra-day data. The results remarkably pick up financial stress periods.  相似文献   
50.
马妮 《价值工程》2013,(31):313-314
在最近几年里,非常规页岩气和页岩油勘探已经进入公众的视线里,引起大家的注意。这些新的成藏是地球物理学许多新发展的催化剂,尤其是新地震属性的应用。近来,三维地震数据和地震属性技术已经在断层、裂缝方位和密度、储层富集带,可能的水力压裂障碍,孔隙压力,岩石力学以及增产的有效性和优化提供信息。下面介绍的是从三维地面地震资料中获得的信息,这些信息是怎样影响非常规页岩发展的。  相似文献   
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