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351.
A central argument in the literature on employee voice is that speaking up at work carries image risk. Challenging this assumption, we propose that voice can in fact positively affect how employees are viewed by others, thereby enhancing their social status. Using theory on status attainment and the fundamental social perception dimensions of agency and communion, we suggest that employee voice will result in higher status evaluations by increasing the extent to which an employee is judged as confident/competent (agency) and other‐oriented/helpful (communion). We conducted a survey study and two experiments to test these hypotheses. The results supported our predictions. Employees who voiced were ascribed higher status than those who did not, and this effect was mediated by judgments of agency (in all three studies) and communion (in two studies). These results highlight the implications of voice behavior for status enhancement within organizations.  相似文献   
352.
Two dominant perspectives of job crafting—the original theory from Wrzesniewski and Dutton ( 2001 ) and the job demands resources perspective from Tims, Bakker, and Derks ( 2012 )—remain separate in research. To synthesize these perspectives, we propose a three‐level hierarchical structure of job crafting, and we identify the aggregate/superordinate nature of each major job crafting construct. The first level of the structure is job crafting orientation, or approach versus avoidance crafting, which we argue is an essential yet often neglected distinction in the literature. We address the debate surrounding cognitive crafting and identify crafting form (behavioral versus cognitive crafting) as the next hierarchical level of constructs. Finally, we concur that job resources and job demands, or crafting content, capture different ways that individuals craft their jobs. Using this integrated hierarchical structure, we were able to review antecedents and outcomes from both perspectives. We show, for example, that approach crafting in its behavioral form is very similar to other proactive behaviors in the way it functions, suggesting a need for closer synthesis with the broader proactive literature, whereas avoidance crafting appears to be less proactive and often dysfunctional. On the basis of our review, we develop a road map for future research.  相似文献   
353.
The role of social context (e.g., leadership, team climate, and organizational support) in shaping employee proactive behavior has received considerable attention and has been investigated across multiple forms of proactive behavior. However, the research has not been well integrated. In this review, we adopt a multilevel approach to synthesize what is known about how social context factors influence employees' proactive behavior, as well as what mechanisms underpin these effects. Our analyses show that leader‐, team‐, and organization‐related social context factors mainly influence employee proactivity through shaping “reason to,” “can do,” and “energized to” states (i.e., proactive motivational states) via individual‐, team‐, and cross‐level processes. That has been most frequently investigated is the effect of the discretionary social context, particularly leadership, on proactive behavior. We also review the interaction effects between social context factors and other factors on employee proactive behavior and found inconsistent support for the motivational‐fit perspective that stimuli with the same directions enhance each other's effect. We offer a research agenda to advance theoretical insights on this important topic.  相似文献   
354.
为研究工作压力对矿工心理社会安全行为的影响机理,探讨安全心理资本的中介作用以及心理社会安全氛围的调节作用,从积极心理学视角出发,对203名一线矿工进行实证分析。研究结果表明:矿工的安全心理资本在其工作压力与心理社会安全行为的负向关系中起中介作用;心理社会安全氛围能调节工作压力与安全心理资本之间的关系;心理社会安全氛围能够调节安全心理资本在工作压力与心理社会安全行为关系间的中介作用。  相似文献   
355.
施工现场作业人员是否佩戴安全帽主要依靠人工检查,存在监管效率低、时效性差等问题,为了实时自动监管作业人员是否佩戴安全帽,提出1种基于机器学习的安全帽佩戴行为检测方法。首先利用深度学习YOLOv3算法检测出现场视频中的施工人员脸部位置,根据安全帽与人脸的关系估算出安全帽潜在区域;然后对安全帽潜在区域图像进行增强处理,使用HOG(方向梯度直方图)提取样本的特征向量;再利用SVM(机器学习的支持向量机)分类器对脸部上方是否有安全帽进行判断,进而实现对施工人员安全帽佩戴行为的实时检测与预警。以某高铁站施工现场为例进行验证,研究数据表明在施工通道和塔吊作业区域,该方法可实时有效检测出工人未佩戴安全帽的行为,识别率达90%。  相似文献   
356.
为了解高速公路空间郁闭度对驾驶员视觉行为和心理状态的影响规律,在山区高速公路开展室外实车试验,采用Dikablis眼镜式眼动仪和Varioport生理记录仪记录了驾驶员的眼动和生理数据,包括注视时间百分比、平均注视时间、扫视幅度、眨眼率、心电、心率、皮电等。结果表明,随空间郁闭度增加,驾驶员皮电和扫视幅度增大,眨眼率和平均注视持续时间减小,视点越来越集中。随着驾驶员的逐渐适应,空间环境对驾驶员的心理影响逐渐减弱。驾驶员主要关注中间靠左区域,目标物为中央分隔带和前方道路。开敞空间下驾驶员对右侧区域有少量关注。半郁闭空间下驾驶员皮电呈现规律性的波动,对于左侧区域的关注明显增多,对右侧区域的注视持续时间较长,视点集中点更远。  相似文献   
357.
Objective: Many studies addressing age-related changes in driving performance focus on comparing young vs. older drivers, which might lead to the biased conclusion that driving performance decreases only after the age of 65. The main aim of the study was to show that changes in driving performance are progressive throughout the adult years.

Methods: A sample of 351 drivers aged 20 to 80 was assessed for their reaction times while driving between road cones. The drivers were exposed to 2 conditions varying according to task complexity. In single task conditions, the drivers performed a full stopping maneuver at a given signal; in dual task conditions, the drivers were distracted before the signal for stopping maneuver was triggered. Reaction times were compared across conditions and age groups.

Results: The results showed that both reaction times and variability of driving performance increased progressively between the ages of 20 and 80. The increase in both reaction times and variability was greater in the complex task condition. The high-performing quarter of elderly drivers performed equally well or better than younger drivers did.

Conclusions: The data clearly supported the claim that driving performance changes steadily across age groups: both mean reaction time and interindividual variability progressively increase with age. In addition, a significant group of older drivers was identified who did not show the expected age-related decrease in performance. The findings have important implications, suggesting that in relation to driving, aging is a progressive phenomenon and may lead to variety of driving performance; age-related studies of driving performance should put more emphasis on investigating changes across the whole driver age range rather than only comparing younger and older drivers.  相似文献   

358.
359.
济宁南部区域耕作层土壤地球化学特征及其成因分析   总被引:1,自引:0,他引:1  
济宁市南部区域是著名的国家商品粮、优质大蒜、优质稻米和有机蔬菜生产基地,由于土壤地球化学特征与农业生产、人类健康关系密切,所以对济宁南部区域耕作层土壤地球化学特征及其成因的研究具有十分重要的意义。本文以济宁南部煤田地区作为典型区域,以耕作层土壤为研究对象,采集了77件耕作层土壤样品,定量分析了As、B、Cd、Co、Cr、Cu、F、Hg、Li、Mn、Mo、Ni、Pb、Sr、Se、Zn、S、Corg、p H、Si O2、TFe2O3、Mg O、Ca O、Na2O、K2O、CEC等共计26项指标。经统计分析发现,济宁南部区域耕作层土壤中地球化学指标含量变异系数的大小顺序为HgCECSCdNa2OMoCa OCorgAsMnCuMg OCoLiNiTFe2O3SeZnFCrPbBSi O2SrK2Op H,其中Hg、CEC和S的变异系数较大,均超过了50%,这一特点与地球化学指标含量频率直方图及平均值与背景值的比对柱状图所显示的特征完全吻合。在摸清耕作层土壤地球化学特征的基础上,采用R型因子分析法对济宁南部区域耕作层土壤地球化学特征的成因进行了详细分析,提取了风化作用和淋溶作用复合因素、蒸发淀积作用和粘土物理化学吸附作用复合因素、植物根际富集因素作用、煤矿生产因素作用等四个因子,其方差贡献率分别为55.022%、12.753%、9.803%、8.009%,四个因子可以用于说明济宁南部区域表层土壤地球化学特征85.587%的形成原因。研究结果可以为研究区今后开展耕作层土壤环境质量评价,以及生态平衡研究奠定基础。  相似文献   
360.
高华中 《地球与环境》2016,44(6):595-599
地球化学元素比值的变化不仅可以指示气候变化和环境特征,也可以揭示气候异常和突变性气候事件。本文通过对沂沭河流域沭埠岭剖面沉积物淋溶系数、残积系数、CaO/MgO、硅铝率、硅铝铁率等气候代用指标的分析,发现研究区7 470~2550 a BP期间的气候变化经历了五个阶段:(1)7 472~6 043 a BP,气候趋向温暖湿润;(2)6 043~4 801 a BP,稳定的暖湿时期;(3)4 801~3 986 a BP,气候向冷干转变;(4)3 986~3 512 a BP,不稳定时期;(5)3 512~2 552 a BP,气候不稳定的波动时期。  相似文献   
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