Solar radiation, which varies over multiple temporal scales, modulates remarkably the evolution of the ionosphere. The solar activity dependence of the ionosphere is a key and fundamental issue in ionospheric physics,...Solar radiation, which varies over multiple temporal scales, modulates remarkably the evolution of the ionosphere. The solar activity dependence of the ionosphere is a key and fundamental issue in ionospheric physics, providing information essential to understanding the variations in the ionosphere and its processes. Selected recent studies on solar activity effects of the ionosphere are briefly reviewed in this report. This report focuses on (1) observations of solar irradiance at X-ray and extreme ultraviolet wavelengths and the outstanding problems of solar proxies, in the view of ionospheric studies, (2) new findings and improved representations of the features of the solar activity dependence of ionospheric key parameters and the corresponding physical processes, (3) possible phenomena in the ionosphere under extremely high and low solar activity conditions that are unique, as indicated by historical solar datasets and the deep solar minimum of solar cycle 23/24, and (4) statistical studies and model simulations of the ionosphere response to solar flares. The above-mentioned studies provide new clues for comprehensively explaining basic processes in the ionosphere and improving the prediction capability of ionospheric models and related applications.展开更多
最低生活保障制度及其瞄准精度是识别和解决城市贫困问题的关键。基于可行能力理论,利用2019年中国家庭金融调查(CHFS2019)中的13503个城市家庭为样本,系统研究代理家计调查(Proxy Means Tests,PMT)对城市低保瞄准偏误及其减贫效果的作...最低生活保障制度及其瞄准精度是识别和解决城市贫困问题的关键。基于可行能力理论,利用2019年中国家庭金融调查(CHFS2019)中的13503个城市家庭为样本,系统研究代理家计调查(Proxy Means Tests,PMT)对城市低保瞄准偏误及其减贫效果的作用。基于OLS统计推断构建城市代理家计调查框架,综合运用对象瞄准法、补差瞄准法分析城市低保识别效率,实证分析FGT指数的变化以检验城市代理家计调查在提升减贫效果方面的表现。研究发现:当前城市低保漏保偏误仍然十分突出,瞄准效率有待提升;代理家计调查在降低漏保率方面优于其在降低错保率方面的表现;与实际瞄准机制相比,代理家计调查在降低贫困广度、贫困深度和贫困群体内部不平等程度的表现突出。优化城市低保制度体系,可引入城市代理家计调查,以有效解决城市低保瞄准偏差问题,提升低保制度的减贫效应。展开更多
基金supported by the National Natural Science Foundation of China (40725014)the Specialized Research Fund for State Key Laboratories
文摘Solar radiation, which varies over multiple temporal scales, modulates remarkably the evolution of the ionosphere. The solar activity dependence of the ionosphere is a key and fundamental issue in ionospheric physics, providing information essential to understanding the variations in the ionosphere and its processes. Selected recent studies on solar activity effects of the ionosphere are briefly reviewed in this report. This report focuses on (1) observations of solar irradiance at X-ray and extreme ultraviolet wavelengths and the outstanding problems of solar proxies, in the view of ionospheric studies, (2) new findings and improved representations of the features of the solar activity dependence of ionospheric key parameters and the corresponding physical processes, (3) possible phenomena in the ionosphere under extremely high and low solar activity conditions that are unique, as indicated by historical solar datasets and the deep solar minimum of solar cycle 23/24, and (4) statistical studies and model simulations of the ionosphere response to solar flares. The above-mentioned studies provide new clues for comprehensively explaining basic processes in the ionosphere and improving the prediction capability of ionospheric models and related applications.
文摘最低生活保障制度及其瞄准精度是识别和解决城市贫困问题的关键。基于可行能力理论,利用2019年中国家庭金融调查(CHFS2019)中的13503个城市家庭为样本,系统研究代理家计调查(Proxy Means Tests,PMT)对城市低保瞄准偏误及其减贫效果的作用。基于OLS统计推断构建城市代理家计调查框架,综合运用对象瞄准法、补差瞄准法分析城市低保识别效率,实证分析FGT指数的变化以检验城市代理家计调查在提升减贫效果方面的表现。研究发现:当前城市低保漏保偏误仍然十分突出,瞄准效率有待提升;代理家计调查在降低漏保率方面优于其在降低错保率方面的表现;与实际瞄准机制相比,代理家计调查在降低贫困广度、贫困深度和贫困群体内部不平等程度的表现突出。优化城市低保制度体系,可引入城市代理家计调查,以有效解决城市低保瞄准偏差问题,提升低保制度的减贫效应。
