This study focuses on the analysis of the effect of meteorological disasters on film plastic greenhouses by typhoons,heavy snow,strong wind,and heavy rain.The data of meteorological disasters from 1998 to 2015 were an...This study focuses on the analysis of the effect of meteorological disasters on film plastic greenhouses by typhoons,heavy snow,strong wind,and heavy rain.The data of meteorological disasters from 1998 to 2015 were analyzed on provincial basis to calculate the damage rate depending on the weather cause.The cumulative damage area is 20279 hm2.The damage rates of typhoons,heavy snow,strong wind,and heavy rain are 46.4%,47.4%,2.5%,and 3.8%,respectively.The damage index of the greenhouse,which is the ratio of the greenhouse area to the cumulative damage area,was proposed to estimate the disaster risk for 17 administrative districts.The damage index data and the cumulative damage areas were divided using the Jenks’Natural Breaks method.The average damage index is 0.66,and the damage indices are high in the metropolitan cities.展开更多
为了应对气候变化、资源短缺与环境污染问题,各国都在积极开发清洁能源,风能作为可再生的清洁能源,得到了世界各国的高度重视。在实现2030年碳排放达峰的目标约束下,近年来,中国风电规模也处于快速增长的阶段。风力发电过程虽然不会排...为了应对气候变化、资源短缺与环境污染问题,各国都在积极开发清洁能源,风能作为可再生的清洁能源,得到了世界各国的高度重视。在实现2030年碳排放达峰的目标约束下,近年来,中国风电规模也处于快速增长的阶段。风力发电过程虽然不会排放温室气体和污染物,但从产业的生命周期角度分析,在设备制造、运输、安装、运行、废弃等环节也会带来一定量的温室气体和污染物的排放,因此风力发电并不是零排放的能源。本文利用全生命周期评价方法对比研究了100 MW海上和陆上风电系统的全生命周期的排放情况,重点分析了不同功率风机的风电场的全生命周期温室气体排放情况,并分析了一般污染物对于环境的影响。研究结果表明:①海上风电场全生命周期温室气体排放量平均为1.49 g CO_(2)/kWh,陆上风电场平均排放量3.62 g CO_(2)/kWh,均远远小于传统火力发电,比较而言,在减少温室气体排放方面,海上风电系统更具优势;②在全生命周期污染物排放方面,海上风电场全生命周期污染物的排放量要小于陆上风电场,且具有更短的能源回报时间,经济效益更高,对环境更友好;③在全生命周期中,风机的生产过程所产生的温室气体排放占到总温室气体排放的40%以上,同时风机生产所排放的污染物对于环境的负面影响最大,约占整个生命周期影响的50%以上;④配备更大功率的风机将有助于减少温室气体和污染物的排放。研究结果可为减少环境污染、实现碳排放达峰目标提供参考依据。展开更多
In order to obtain a deeper understanding of the behavior of the structure under high wind load,this paper conducted an experimental study on a full-scale L-shaped single story light frame wood house under the uniform...In order to obtain a deeper understanding of the behavior of the structure under high wind load,this paper conducted an experimental study on a full-scale L-shaped single story light frame wood house under the uniform lateral load simulated using a gasbag.The investigation involved the performance of light frame wood structure after it experienced the repeated cyclic lateral wind load as well as the performance of the structure under the ultimate lateral load.Then,the study verified that light frame wood structure can resist repeated cyclic wind loads without observable degradation in stiffness during the anticipated serve life,and recommended shear wall percent drift restriction for lateral wind load design of wood structure in serviceability limit states is 1/400 drift,and in ultimate limit states is 1/80 drift.The conclusions of this paper can be benefit for the engineering practice of the light frame wood structures in high wind load regions.展开更多
基金support of“Research Program for Agriculture Science&Technology Development(PJ011397)”Rural Development Administration,Republic of Korea.
文摘This study focuses on the analysis of the effect of meteorological disasters on film plastic greenhouses by typhoons,heavy snow,strong wind,and heavy rain.The data of meteorological disasters from 1998 to 2015 were analyzed on provincial basis to calculate the damage rate depending on the weather cause.The cumulative damage area is 20279 hm2.The damage rates of typhoons,heavy snow,strong wind,and heavy rain are 46.4%,47.4%,2.5%,and 3.8%,respectively.The damage index of the greenhouse,which is the ratio of the greenhouse area to the cumulative damage area,was proposed to estimate the disaster risk for 17 administrative districts.The damage index data and the cumulative damage areas were divided using the Jenks’Natural Breaks method.The average damage index is 0.66,and the damage indices are high in the metropolitan cities.
文摘为了应对气候变化、资源短缺与环境污染问题,各国都在积极开发清洁能源,风能作为可再生的清洁能源,得到了世界各国的高度重视。在实现2030年碳排放达峰的目标约束下,近年来,中国风电规模也处于快速增长的阶段。风力发电过程虽然不会排放温室气体和污染物,但从产业的生命周期角度分析,在设备制造、运输、安装、运行、废弃等环节也会带来一定量的温室气体和污染物的排放,因此风力发电并不是零排放的能源。本文利用全生命周期评价方法对比研究了100 MW海上和陆上风电系统的全生命周期的排放情况,重点分析了不同功率风机的风电场的全生命周期温室气体排放情况,并分析了一般污染物对于环境的影响。研究结果表明:①海上风电场全生命周期温室气体排放量平均为1.49 g CO_(2)/kWh,陆上风电场平均排放量3.62 g CO_(2)/kWh,均远远小于传统火力发电,比较而言,在减少温室气体排放方面,海上风电系统更具优势;②在全生命周期污染物排放方面,海上风电场全生命周期污染物的排放量要小于陆上风电场,且具有更短的能源回报时间,经济效益更高,对环境更友好;③在全生命周期中,风机的生产过程所产生的温室气体排放占到总温室气体排放的40%以上,同时风机生产所排放的污染物对于环境的负面影响最大,约占整个生命周期影响的50%以上;④配备更大功率的风机将有助于减少温室气体和污染物的排放。研究结果可为减少环境污染、实现碳排放达峰目标提供参考依据。
基金Sponsored by the National Natural Science Foundation of China(Grant No. 50508012)
文摘In order to obtain a deeper understanding of the behavior of the structure under high wind load,this paper conducted an experimental study on a full-scale L-shaped single story light frame wood house under the uniform lateral load simulated using a gasbag.The investigation involved the performance of light frame wood structure after it experienced the repeated cyclic lateral wind load as well as the performance of the structure under the ultimate lateral load.Then,the study verified that light frame wood structure can resist repeated cyclic wind loads without observable degradation in stiffness during the anticipated serve life,and recommended shear wall percent drift restriction for lateral wind load design of wood structure in serviceability limit states is 1/400 drift,and in ultimate limit states is 1/80 drift.The conclusions of this paper can be benefit for the engineering practice of the light frame wood structures in high wind load regions.