期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
Sleep Quality and Emotional Adaptation among Freshmen in Elite Chinese Universities during Prolonged COVID-19 Lockdown:The Mediating Role of Anxiety Symptoms
1
作者 Xinqiao Liu linxin zhang Xinran zhang 《International Journal of Mental Health Promotion》 2024年第2期105-116,共12页
Under the effects of COVID-19 and a number of ongoing lockdown tactics,anxiety symptoms and poor sleep quality have become common mental health issues among college freshmen and are intimately related to their emotion... Under the effects of COVID-19 and a number of ongoing lockdown tactics,anxiety symptoms and poor sleep quality have become common mental health issues among college freshmen and are intimately related to their emotional adaptation.To explore this connection,this study gathered data from a sample of 256 freshmen enrolled in an elite university in China in September 2022.The association between sleep quality,anxiety symptoms,and emotional adaptation was clarified using correlation analysis.Additionally,the mediating function of anxiety symptoms between sleep quality and emotional adaptation was investigated using a structural equation model.The results reveal that:(1)Chinese elite university freshmen who were subjected to prolonged lockdown had poor sleep quality and mild anxiety symptoms;(2)a significant positive correlation between poor sleep quality and anxiety symptoms was identified;(3)anxiety symptoms were found to have a significant negative impact on emotional adaptation;(4)poor sleep quality had a negative impact on emotional adaptation through anxiety symptoms.This research makes a valuable contribution by offering insights into the intricate relationship between sleep quality and emotional adaptation among freshmen in elite Chinese universities during prolonged lockdown conditions,and it is beneficial for schools and educators to further improve school schedules and psychological health initiatives. 展开更多
关键词 COVID-19 pandemic sleep quality emotional adaptation anxiety symptoms lockdown FRESHMEN
暂未订购
压实黄土场地湿陷沉降机理与黄土高原平山造城适宜性 被引量:8
2
作者 祁生文 侯晓坤 +8 位作者 于永堂 张亚国 胡燮 张琳鑫 李志清 郭松峰 张帆宇 李同录 彭建兵 《科学通报》 EI CAS CSCD 北大核心 2023年第14期1844-1860,共17页
黄土高原城市用地紧张与用地需求日益增大的矛盾使得平山造城工程应运而生,大规模平山造城工程会引起场地水文环境变化,诱发填土地基失稳、建筑物破坏等,其工程长期适宜性是人们最关切的问题.通过现场调研、原位监测、室内试验、模型试... 黄土高原城市用地紧张与用地需求日益增大的矛盾使得平山造城工程应运而生,大规模平山造城工程会引起场地水文环境变化,诱发填土地基失稳、建筑物破坏等,其工程长期适宜性是人们最关切的问题.通过现场调研、原位监测、室内试验、模型试验、数值模拟和InSAR分析等工作,探究了压实黄土场地湿陷沉降机理及黄土高原平山造城工程适宜性.研究结果发现,场地压实黄土的物理力学性质和微观结构同天然黄土差异较大,其力学性质差、孔隙连通性差、空间变异性大;湿陷变形本质为含水率增大引起土体刚度降低而发生的压密变形,湿陷过程中压实黄土的结构变化整体上表现为颗粒间孔隙的局部压密,颗粒及孔隙形态基本不变;非饱和压实黄土的蠕变特性同屈服应力与上覆荷载的大小密切相关,增大压实土体的干密度可提高屈服应力,缩短蠕变稳定时间,还可显著降低土体的渗透特性;典型平山造城场地厚层压实黄土中的含水状态基本能维持长期稳定,有缓慢的向下水流补给地下水;场地累积变形量随填方土厚度增大而增大,地表变形减缓,沉降速率递减,预测工后15年场地变形可达稳定;增大压实土体干密度和合理设置地下水排水设施可有效减小地表总变形量、变形稳定期和局部破坏.研究结果论证了整体地基的长期稳定性和局部灾害的工程可控性,从理论和实践上证实平山造城工程基本可行,提出了黄土高原平山造城工程的适宜性原则,为未来的平山造城工程提供科学指导. 展开更多
关键词 黄土高原 平山造城 水分迁移 湿陷机理 沉降规律
原文传递
Distributed scheduling for multi-energy synergy system considering renewable energy generations and plug-in electric vehicles:A level-based coupled optimization method 被引量:2
3
作者 linxin zhang Zhile Yang +6 位作者 Qinge Xiao Yuanjun Guo Zuobin Ying Tianyu Hu Xiandong Xu Sohail Khan Kang Li 《Energy and AI》 EI 2024年第2期213-226,共14页
Multi-energy synergy systems integrating high-penetration large-scale plug-in electric vehicles, distributed renewable energy generations, and battery energy storage systems have great potential to reduce the reliance... Multi-energy synergy systems integrating high-penetration large-scale plug-in electric vehicles, distributed renewable energy generations, and battery energy storage systems have great potential to reduce the reliance of the grid on traditional fossil fuels. However, the random charging characteristics of plug-in electric vehicles and the uncertainty of photovoltaics may impose an additional burden on the grid and affect the supply–demand equilibrium. To address this issue, judicious scheduling optimization offers an effective solution. In this study, considering charge and discharge management of plug-in electric vehicles and intermittent photovoltaics, a novel Multi-energy synergy systems scheduling framework is developed for solving grid instability and unreliability issues. This formulates a large-scale mixed-integer problem, which calls for a powerful and effective optimizer. The new binary level-based learning optimization algorithm is proposed to address nonlinear large-scale high-coupling unit commitment problems. To investigate the feasibility of the proposed scheme, numerical experiments have been carried out considering multiple scales of unit numbers and various scenarios. Finally, the results confirm that the proposed scheduling framework is reasonable and effective in solving unit commitment problems, can achieve 3.3% cost reduction and demonstrates superior performance in handling large-scale energy optimization problems. The integration of plug-in electric vehicles, distributed renewable energy generations, and battery energy storage systems is verified to reduce the output power of 192.72 MW units during peak periods to improve grid stability. Therefore, optimizing energy utilization and distribution will become an indispensable part of future power systems. 展开更多
关键词 Electric vehicle Unit commitment Renewable energy Battery energy storage system Synergy optimization
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部