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11.
This research seeks for improved understanding regarding the interaction of meaningful work and the work–family interface. Existing literature suggests that experiencing a sense of calling toward work makes the work domain particularly salient to employees compared to other life domains. In this article, we draw on this idea, rooted in identity theory, to hypothesize that a sense of calling toward work diminishes the effects of work–family conflict and work–family enrichment on employee's job and life satisfaction. We test these ideas in two studies. First, we surveyed an alumni sample of 598 employees from various jobs, industries, and job levels. Then, in a constructive replication, we surveyed 327 employees using a time-lagged design. Calling was found to significantly buffer the effect of work–family conflict on job satisfaction in Study 2, but not Study 1. Calling did not buffer the effect of conflict on life satisfaction in either study. However, both studies demonstrated that calling attenuated (substituted for) the effect of work–family enrichment on job satisfaction. Study 1 supported the idea that calling attenuates the effect of enrichment on life satisfaction; however, this interactive effect was reversed in Study 2, contrary to expectations. We discuss implications for theory and practice related to callings and career choices, as well as for the role of calling and work identity in the work–family interface.  相似文献   
12.
Background. The effect of physical exercise in the workplace (PEW) on health promotion of workers is contradictory. Objective. To evaluate the effects of the PEW in musculoskeletal disorders (MSDs), perception of stress and quality of life in workers. Methods. The participants were divided into two groups: control group (n?=?46) including non-participant workers of the PEW program, and PEW group (n?=?50) including workers who regularly participate in the exercise program. All workers answered the Nordic general questionnaire, the perceived stress scale and the quality-of-life questionnaire. Results. The PEW group reported a lower prevalence of MSDs for the trunk in the last 7 days and 12 months (p?=?0.021 and p?=?0.001, respectively), and for the upper limbs in the last 12 months (p?=?0.001) compared with the control group. The results for the perception of stress and quality of life showed no significant differences between the groups. Conclusion. PEW is a potential method to reduce MSDs in workers, but it was not efficient in reducing stress levels or improving the quality of life of the workers.  相似文献   
13.
硫酸雾测试方法若干问题思考   总被引:1,自引:1,他引:0  
简述了我国硫酸雾测试方法的发展历史,分析和总结了《固定污染源废气硫酸雾的测定离子色谱法》(HJ 544—2016)存在的一些争议和问题,包括硫酸雾的定义、测试方法的干扰控制等。分析认为,相比《硫酸工业污染物排放标准》(GB 26132—2010),HJ 544—2016对硫酸雾的定义更加合理。实验结果表明:硫酸盐是测试方法条件下的目标物,滤筒可以显著地捕捉硫酸盐。9组样品滤筒中,被测目标物所占比例为7.9%~69.1%;滤筒和前吸收液中,被测目标物所占比例为93.7%~97.8%。HJ 544—2016新增加的两级串联碱液吸收瓶可以较完全地捕集穿透滤筒后的硫酸雾,同时也会捕集SO2。SO2会对硫酸雾测试产生正干扰,约42.9%的SO2在被吸收后转化为硫酸雾。  相似文献   
14.
为推广非金属复合管在油田集输油领域的应用,明确其在集输环境中的老化特性是关键问题。基于集输油现场的工程条件,针对长庆油田试用的4731B型钢丝缠绕增强复合管,以采出原油、采出水为实验介质,通过挂片实验、水压爆破实验,借助电镜扫描、拉伸测试对复合管内衬层老化行为、拉伸性能以及复合管极限承压与老化特性进行研究。结果表明:采出原油与采出水均可渗透扩散进入内衬层内部,还会发生局部深入渗透;采出原油、采出水的局部渗透速率分别可达3.4,10.6 mm/a;在某些工况下,内衬层表面产生裂纹;短时间(168 h)内的介质渗透甚至裂纹对其机械性能影响较小,而光氧老化影响显著;现场服役813 d后,复合管极限承压下降2.79%,表明复合管承压性能稳定。  相似文献   
15.
Objective: A novel anthropomorphic test device (ATD) representative of the 50th percentile male soldier is being developed to predict injuries to a vehicle occupant during an underbody blast (UBB). The main objective of this study was to develop and validate a finite element (FE) model of the ATD lower limb outfitted with a military combat boot and to insert the validated lower limb into a model of the full ATD and simulate vertical loading experiments.

Methods: A Belleville desert combat boot model was assigned contacts and material properties based on previous experiments. The boot model was fit to a previously developed model of the barefoot ATD. Validation was performed through 6 matched pair component tests conducted on the Vertically Accelerated Loads Transfer System (VALTS). The load transfer capabilities of the FE model were assessed along with the force-mitigating properties of the boot. The booted lower limb subassembly was then incorporated into a whole-body model of the ATD. Two whole-body VALTS experiments were simulated to evaluate lower limb performance in the whole body.

Results: The lower limb model accurately predicted axial loads measured at heel, tibia, and knee load cells during matched pair component tests. Forces in booted simulations were compared to unbooted simulations and an amount of mitigation similar to that of experiments was observed. In a whole-body loading environment, the model kinematics match those recorded in experiments. The shape and magnitude of experimental force–time curves were accurately predicted by the model. Correlation between the experiments and simulations was backed up by high objective rating scores for all experiments.

Conclusion: The booted lower limb model is accurate in its ability to articulate and transfer loads similar to the physical dummy in simulated underbody loading experiments. The performance of the model leads to the recommendation to use it appropriately as an alternative to costly ATD experiments.  相似文献   

16.
为避免因腐蚀导致油气管道失效,针对因管道特性和腐蚀尺寸的不确定性使得管道剩余强度成为概率模型的特点,建立了腐蚀管道强度损失随机模型;借助可靠性理论,通过分析管道腐蚀进程的时变性特点,将管道系统由损伤积累和抗力衰减导致的剩余强度随机化;提出基于穿越率的腐蚀油气管道失效评定及安全寿命预测方法。研究结果表明:腐蚀速率和运行压力对管道失效概率及安全寿命影响显著,管道尺寸影响适中,而相关系数和拉伸强度影响较小;若腐蚀速率Va=0.2 mm/a,VL=10 mm/a或局部腐蚀缺陷半径达到管道壁厚的0.5倍时,建议作为重点风险段监测并检修。所建方法是对腐蚀油气管道运营监控和风险评估的有益补充。  相似文献   
17.
为提高我国城市燃气风险管理水平,帮助风险管理者科学地分配维护资源,探讨提出了我国城市燃气事故生命损失风险可接受标准;采用AIR指标法确定了个人风险可接受标准范围为(2.397 3×10-7,4.794 7×10-7);运用F-N曲线法结合ALARP原则,确定了社会风险可接受标准,最大可接受风险的截距为4.794 7×10-7,可忽略风险的截距为4.794 7×10-8;利用生活质量指数推导模型,计算了达到城市燃气事故可忽略风险水平的最优安全投入成本;基于风险动态原则,分析提出了风险可接受标准的更新办法。研究结果表明:我国城市燃气行业可接受风险水平低于煤矿、大坝、化工等危险行业的可接受风险水平;虽然我国城市燃气事故死亡率逐年降低,但要达到可忽略的风险水平,每年还需大量安全资金投入。  相似文献   
18.
伴随我国经济发展的进步,虽然农村的生活水平得到一定的改善,但是并没有根据实际情况将相关生态处理技术应用,导致农村污水处理的效率无法有效的提升,严重影响农村的发展。基于此,本文主要分析了农村生活污水处理的方式,以及污水处理不当对人们的危害与影响,并阐述了农村污水处理的主要对策与方案,笔者根据自身经验提出相应的建议与意见。  相似文献   
19.
为了探索非金属输送管道泄漏规律,从数值模拟和试验两个角度,对液体PE管道发生泄漏前后管道内流体与泄漏口的流动状态进行了对比分析,为判定管道泄漏提供了依据。运用FLUENT软件针对PE液体管道泄漏,在不同孔径、不同压力下,构建管道泄漏模型分别进行仿真,分析不同泄漏情景下压力梯度的分布规律。同时在近似相同条件下进行PE管道两点泄漏模拟试验。结果显示:数值模拟与试验结果基本一致,泄漏孔处压力、流速均与管内初始压力成正相关;初始压力和孔径的增大,会导致管内压力下降速度上升,但最终会趋于稳定值。  相似文献   
20.
李超 《装备环境工程》2020,17(11):103-107
目的通过对比试验室加速腐蚀试验结果,获得耐盐雾腐蚀性能最佳的表面防护体系。方法选用2024铝合金的几种不同表面防护体系,进行盐雾腐蚀试验。通过宏观腐蚀形貌和涂层失光率变化来分析判定表面防护体系耐腐蚀性能,获得抗腐蚀性能优异的表面防护体系。结果综合内外部防护体系宏观腐蚀形貌和失光率情况来看,阿洛丁氧化和所配套的三套涂层系统的盐雾适应性较差。结论内部防护体系推荐采用铬酸阳极化+10P4-X底漆防护体系;外部防护体系推荐采用铬酸阳极化+10P20-X底漆+ECL面漆防护体系。  相似文献   
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