Kirigami is one of the most traditional Chinese arts(named"paper-cuts"or"jianzhi")that has been widely used in window decorations,gift cards,festivals,ceremonies,etc.Through cutting and folding fla...Kirigami is one of the most traditional Chinese arts(named"paper-cuts"or"jianzhi")that has been widely used in window decorations,gift cards,festivals,ceremonies,etc.Through cutting and folding flat objects into 3D shapes,the knowledge of kirigami has recently aroused tremendous interests in both sciences and technologies,including deployable designs of solar arrays,biomedical devices and micro-/展开更多
The Thornthwaite moisture index, an index of the supply of water （precipitation） in an area relative to the climatic demand for water （potential evapotranspiration）, was used to examine the spatial and temporal va...The Thornthwaite moisture index, an index of the supply of water （precipitation） in an area relative to the climatic demand for water （potential evapotranspiration）, was used to examine the spatial and temporal variation of drought and to verify the influence of environmental factors on the drought in the Hengduan Mountains, China. Results indicate that the Thornthwaite moisture index in the Hengduan Mountains had been increasing since 1960 with a rate of 0.1938/yr. Annual Thomthwaite moisture index in Hengduan Mountains was between -97.47 and 67.43 and the spatial heterogeneity was obvious in different seasons. Thomthwaite moisture index was high in the north and low in the south, and the monsoon rainfall had a significant impact on its spatial distribution. The tendency rate of Thomthwaite moisture index variation varied in different seasons, and the increasing trends in spring were greater than that in summer and autumn. However, the Thomthwaite moisture index decreased in winter. Thomthwaite moisture index increased greatly in the north and there was a small growth in the south of Hengduan Mountains. The increase of precipitation and decrease of evaporation lead to the increase of Thomthwaite moisture index. Thornthwaite moisture index has strong correlation with vegetation coverage. It can be seen that the correlation between Normalized Difference Vegetation Index （NDVI） and Thomthwaite moisture index was positive in spring and summer, but negative in autumn and winter. Correlation between Thornthwaite moisture index and relative soil relative moisture content was positive in spring, summer and autumn, but negative in winter. The typical mountainous terrain affect the distribu- tion of temperature, precipitation, wind speed and other meteorological factors in this region, and then affect the spatial distribution of Thomthwaite moisture index. The unique ridge-gorge terrain caused the continuity of water-heat distribution from the north to south, and the water-heat was stronger than that from the east to west part, and thus determined the spatial distribution of Thornthwaite mois- ture index. The drought in the Hengduan Mountains area is mainly due to the unstable South Asian monsoon rainfall time.展开更多
本文以《非洲媒体研究》(Journal of African Media Studies)2009年至2019年间发表的221篇研究论文为样本,从总体情况、研究对象、研究议题、理论框架、研究方法等五个方面对当前的非洲媒体研究进行了"浅描"。研究发现,当前...本文以《非洲媒体研究》(Journal of African Media Studies)2009年至2019年间发表的221篇研究论文为样本,从总体情况、研究对象、研究议题、理论框架、研究方法等五个方面对当前的非洲媒体研究进行了"浅描"。研究发现,当前非洲媒体研究具有以下几个显著特点:总体而言,非洲媒体研究处于国际传播研究的边缘位置,与非洲大陆在世界体系中的边缘位置相一致;研究对象方面,以都市精英群体的媒体实践为主,占非洲人口大多数的农村地区的媒体实践则鲜有涉及;研究议题方面,由以往的发展议题为主转变为当前的政治议题为主,主要与非洲大陆的政治改革及媒体生态变革相关;理论框架方面,具有明显的"西方中心性",非洲本土理论处于绝对的边缘位置;研究方法方面,以定性研究方法为主,定量研究方法极少,主要与非洲社会现实的特殊性相关。展开更多
基金supported by the National Natural Science Foundation of Chinathe Ministry of Science and Technology of China+2 种基金CASthe Chinese Scholarship Councilgrants from US
文摘Kirigami is one of the most traditional Chinese arts(named"paper-cuts"or"jianzhi")that has been widely used in window decorations,gift cards,festivals,ceremonies,etc.Through cutting and folding flat objects into 3D shapes,the knowledge of kirigami has recently aroused tremendous interests in both sciences and technologies,including deployable designs of solar arrays,biomedical devices and micro-/
基金Under the auspices of Chinese Postdoctoral Science Foundation(No.2015M570864)Open-ended Fund of State Key Laboratory of Cryosphere Sciences,Chinese Academy of Sciences(No.SKLCS-OP-2014-11)+2 种基金Northwest Normal University Young Teachers Scientific Research Ability Promotion Plan(No.NWNU-LKQN-13-10)National Natural Science Foundation of China(No.41273010,41271133)Major National Research Projects of China(No.2013CBA01808)
文摘The Thornthwaite moisture index, an index of the supply of water （precipitation） in an area relative to the climatic demand for water （potential evapotranspiration）, was used to examine the spatial and temporal variation of drought and to verify the influence of environmental factors on the drought in the Hengduan Mountains, China. Results indicate that the Thornthwaite moisture index in the Hengduan Mountains had been increasing since 1960 with a rate of 0.1938/yr. Annual Thomthwaite moisture index in Hengduan Mountains was between -97.47 and 67.43 and the spatial heterogeneity was obvious in different seasons. Thomthwaite moisture index was high in the north and low in the south, and the monsoon rainfall had a significant impact on its spatial distribution. The tendency rate of Thomthwaite moisture index variation varied in different seasons, and the increasing trends in spring were greater than that in summer and autumn. However, the Thomthwaite moisture index decreased in winter. Thomthwaite moisture index increased greatly in the north and there was a small growth in the south of Hengduan Mountains. The increase of precipitation and decrease of evaporation lead to the increase of Thomthwaite moisture index. Thornthwaite moisture index has strong correlation with vegetation coverage. It can be seen that the correlation between Normalized Difference Vegetation Index （NDVI） and Thomthwaite moisture index was positive in spring and summer, but negative in autumn and winter. Correlation between Thornthwaite moisture index and relative soil relative moisture content was positive in spring, summer and autumn, but negative in winter. The typical mountainous terrain affect the distribu- tion of temperature, precipitation, wind speed and other meteorological factors in this region, and then affect the spatial distribution of Thomthwaite moisture index. The unique ridge-gorge terrain caused the continuity of water-heat distribution from the north to south, and the water-heat was stronger than that from the east to west part, and thus determined the spatial distribution of Thornthwaite mois- ture index. The drought in the Hengduan Mountains area is mainly due to the unstable South Asian monsoon rainfall time.
文摘本文以《非洲媒体研究》(Journal of African Media Studies)2009年至2019年间发表的221篇研究论文为样本,从总体情况、研究对象、研究议题、理论框架、研究方法等五个方面对当前的非洲媒体研究进行了"浅描"。研究发现,当前非洲媒体研究具有以下几个显著特点:总体而言,非洲媒体研究处于国际传播研究的边缘位置,与非洲大陆在世界体系中的边缘位置相一致;研究对象方面,以都市精英群体的媒体实践为主,占非洲人口大多数的农村地区的媒体实践则鲜有涉及;研究议题方面,由以往的发展议题为主转变为当前的政治议题为主,主要与非洲大陆的政治改革及媒体生态变革相关;理论框架方面,具有明显的"西方中心性",非洲本土理论处于绝对的边缘位置;研究方法方面,以定性研究方法为主,定量研究方法极少,主要与非洲社会现实的特殊性相关。
