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131.
132.
本文从当前形势发展的要求出发,针对目前广东农业面临的各种危机,阐述了土肥工作在今后的农业生产中仍具有重要的地位,呼吁今后一定要加强土肥工作;明确提出了今年广东土肥工作的主要任务和要求,强调要力争开创广东土肥工作的新局面. 相似文献
133.
Resin is an important building material in the nests of honeybees, but little is known about how it is handled within the nest and how its collection is controlled. We studied the functional organization of resin work to better understand how a colony adaptively controls its intake of resin. Two hypotheses have been proposed for how resin collectors stay informed of the need for additional resin: (1) the unloading difficulty hypothesis (resin need is sensed indirectly by the unloading delay) and (2) the caulking activity hypothesis (resin need is sensed directly while engaged in using resin). A falsifiable prediction of the latter hypothesis, but not of the former, is that resin collectors not only gather resin outside the hive but also regularly handle resin inside the hive (taking it from other bees and using it to caulk crevices). Consistent with this prediction are our findings that in the resin sector of a colony’s economy, unlike in the pollen, nectar, and water sectors, there is no strict division of labor between the collectors and the users of a material. Over the course of a day, bees seen collecting resin were also commonly seen using resin. Moreover, we found that the unloading locations of resin collectors are unlike those of water and nectar collectors, being deep inside the hive (at the sites of resin use) rather than at the hive entrance. This arrangement facilitates the engagement in resin use by resin collectors. We conclude that the caulking activity hypothesis is well-supported, but that the unloading difficulty hypothesis also remains viable, for we found that resin collectors experience variable delays in getting rid of their loads, from less than 15 min to more than an hour, consistent with this hypothesis. The stage is now set for experimental tests of these two hypotheses. Both may be correct, which if true will imply that social insect workers, despite their small brains, can acquire and integrate information from multiple sources to improve their knowledge of conditions within the colony. 相似文献
134.
曾冰 《湖南环境生物职业技术学院学报》2006,12(3):323-327
在数字作品著作权越来越频繁受到侵犯的今天,如何对其进行有效的保护,维护著作权人的利益,给法律提出了更高的要求.因此,来阐述与著作权保护相关的几个理论问题,提出对网络音乐作品保护的几点建议,以形成一个以保护音乐作品著作权人利益为宗旨的保护体制. 相似文献
135.
作为非回转对称成形试验研究的一部分,进行了大量的矩形盒拉深试验。指出纯铜薄板的各向异性对矩形盒拉深成形性的影响不十分显著。增大凸模形状参数rc/w,成形中法兰短边和曲边材料向凹模口的流入速度减小,曲边变形加工度增大,是使成形极限降低的原因之一。rc/w=0.1附近,极限成形高度hmax最大。 相似文献
136.
在基坑开挖中,坚持信息化施工管理,采取多种手段对基坑安全进行监测是非常必要的。利用监测资料的分析结果,可及时发现基坑开挖过程中出现的问题,可以有针对性地采取措施,调整方案,保证施工顺利进行。 相似文献
137.
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
138.
Employees who work periodically in both a traditional office and home office (part‐time teleworkers) face opportunities and risks related to both working locations. As self‐leadership might play a crucial role in this context, we examined within‐person variations in self‐leadership (self‐reward, self‐punishment, self‐cueing, self‐goal setting, imagining successful performance, and evaluation of beliefs and assumptions) on home days and office days. In a typical workweek, 195 part‐time teleworkers filled out daily surveys (729 days), and we examined the relationship between working location (office and home) and self‐leading behavior as well as the mediating role of autonomy. Finally, we investigated whether self‐leading behavior relates to ego depletion and work satisfaction at the end of the working day. Multilevel analyses revealed that part‐time teleworkers reported higher use of self‐reward, self‐goal setting, and visualization of successful performance on home days than on office days. The association between working location and self‐reward, self‐goal setting, visualization of successful performance, and evaluation of beliefs and assumptions was mediated by autonomy. There were no indirect effects of working location on ego depletion through self‐leadership. However, we found that on home days, part‐time teleworkers were more satisfied with their job at the end of the workday through self‐goal setting. 相似文献
139.
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
140.
为了实现重大生产安全事故救援费用的公平负担,保障救援机制的可持续性,通过规范分析和比较分析,探讨了在第三方队伍参与救援的情况下,重大生产安全事故救援费用的承担原则和实现机制。研究结果表明:第三方队伍参与事故救援所产生的当次费用原则上必须由事故责任单位承担,但在其拖欠费用或者暂时缺乏支付能力的情况下,应当由承担应急救援职责的事发地政府先行垫付;由此在事发地政府和事故责任单位之间产生的是公法之债,可以通过行政强制执行的方式加以追偿。 相似文献