海洋平台冰激疲劳时域精细评估

为了评估冰区平台在服役期内的安全可靠性,给出了平台冰激疲劳时域精细评估的详细流程。根据海冰漂移方向、冰速和冰厚的概率分布特征,确立冰激振动分析的24个疲劳予工况。考虑平台桩柱的不同结构型式和冰-结构耦合作用．分别采用简化冰力函数模型和Sodhi改进模型对平台中锥体结构和直立桩柱结构进行冰激动态响应分析;建立管节点精细有限元模型计算热点应力集中系数,从而得到管节点的疲劳应力时程,并利用雨流计数法进行统计．计算整个疲劳环境的等效应力幅以及相应的循环次数,最后利用Miner线性累积损伤准则计算疲劳损失和疲劳寿命。结果表明：4根钭撑杆上的支管冰激疲劳损伤最大,应作为今后检测的重点部位。     

厚壁筒体环焊缝冷裂纹评定

用断裂力学理论评定冷裂纹时,首先应辨别是何种冷裂纹,如果是延迟裂纹,即使裂纹很短,也是不允许的。因为合成塔运行时,氢连续不断地向裂纹部位形成的三向应力峰值区进行扩散,并使裂纹不停地扩展。     

油井压裂选井方法在C油田中的应用

随着油田的不断深入开发,压裂改造是油藏开发获取工业油流的必须手段。为确保油井压裂的效果与经济效益,提升油井压裂方案的符合率,避免传统上压裂选井的经验性与盲目性,依据近些年来压裂选井的实践,应用模糊数学分析的方法,建立了适合C油田的压裂选井方法,即模糊评判分析方法。通过对模型进行实际运算应用,其结果与该地区实际压裂的施工结果具有很好的符合性。研究成果为C油田可持续开发奠定基础,对于指导油田压裂选井工作具有重要意义。     

物流配送中心拣选作业的人因工程量化评估

基于人因工程视角,探究电子商务模式下新兴的物流配送中心拣选作业的工程负荷与职业健康,研究选取能量代谢量、心率等指标,量化物流拣选作业环节的劳动强度等级,并利用疲劳强度评估提出合理的作息安排,即当劳动负荷为5km/h时,物流拣选劳动者平均每工作48min后,需要休息6min;当劳动负荷为7km/h时,物流拣选劳动者平均每工作19min后,需要休息6min。该研究拟在改善电子商务模式下物流配送中心衔接不紧密、响应速度慢等瓶颈问题的同时,关注劳动密集型作业环节的工程负荷与职业健康。     

Staging a comeback? The influencing mechanism of tourist crowding perception on adaptive behavior

An increasing number of studies have recently elucidated the serious negative effects of tourist crowding. However, how tourists cope with crowding and adopt adaptive responses remains unclear. Thus, this study qualitatively identified the mechanism of tourist crowding perception of adaptive behavior from interviewees and then quantitatively validated the mechanism through the mediation of tourist fatigue and negative emotions, as well as the moderation of peer emotion contagion. Tourists were more likely to return to a destination and engage in temporal replacement behavior through the mediating effect of tourist fatigue, but it was also found that peer emotional contagion interferes with two paths that explain how tourist crowding perception influences tourist emotion change or state variation, impacting adaptive behavior responses. Consequently, we recommend diverting tourists, focusing on alleviating fatigue and negative emotions and channeling the peers’ negative emotions to mitigate the negative impact of tourist crowding.