Background Generally speaking. Chinese college graduates in the fifties and sixties took Russian as their second language, and those who graduated in the seventies had no second language to speak of. Now, in the years...Background Generally speaking. Chinese college graduates in the fifties and sixties took Russian as their second language, and those who graduated in the seventies had no second language to speak of. Now, in the years of our Open Door Policy, they find they have to learn some English and learn it quickly. They try to learn from radio and TV and many take English courses of 4 to 6 months, with varying degree of success. Their chief stumbling blocks展开更多
为了解决高比例分布式电源(distributed generation,DG)大规模并网后实时量测数目缺失、传统预测辅助状态估计方法(forecasting-aided state estimation,FASE)估计精度有限等问题,提出了基于改进Crossformer伪量测构建的主动配电网FASE...为了解决高比例分布式电源(distributed generation,DG)大规模并网后实时量测数目缺失、传统预测辅助状态估计方法(forecasting-aided state estimation,FASE)估计精度有限等问题,提出了基于改进Crossformer伪量测构建的主动配电网FASE方法。首先,基于最大信息系数法(maximal information coefficient,MIC)筛选出高相关性的输入特征,提高预测模型的精度;然后,通过全变差正则化技术(total variation regularized,TV)优化鲁棒主成分分析法(robust principal component analysis,RPCA),构建TRPCA层,并将其嵌入到Crossformer中,以填补Crossformer无法有效处理非高斯噪声的空白;最后,利用改进的预测模型进行超短期负荷预测,经潮流计算得到节点伪量测,在量测不足情况下补全缺失数据,并结合扩展卡尔曼滤波器(extended Kalman filter,EKF)进行状态估计。在IEEE 33节点和IEEE 118节点标准配电网上进行仿真测试,结果表明所提方法在估计精度和鲁棒性等方面具有一定优势,可为主动配电网FASE提供参考。展开更多
目的了解农村HIV感染者/AIDS患者(people living with HIVand AIDS,PLWHA)的心理健康状况。方法采用一般情况调查表和症状自评量表(SCL-90)对192例HIV/AIDS人员进行调查。结果192例PLWHA人员SCL-90总分、阳性项目数和各因子分均高于中...目的了解农村HIV感染者/AIDS患者(people living with HIVand AIDS,PLWHA)的心理健康状况。方法采用一般情况调查表和症状自评量表(SCL-90)对192例HIV/AIDS人员进行调查。结果192例PLWHA人员SCL-90总分、阳性项目数和各因子分均高于中国常模(各项P<0.05);心理问题阳性检出率83.9%;AIDS患者总分、阳性因子数、各因子分均显著高于HIV感染者(P<0.01);不同文化程度分组之间SCL-90各个因子的比较,除抑郁因子外,其他因子均有显著差异(P<0.05);不同经济收入之间有显著差异,接受政府救济才能维持基本开支组显著高于不需救济组(P<0.01)。性别、年龄、感染方式之间均无显著差异。结论被调查的HIV/AIDS人群存在突出的心理健康问题,应建立便捷有效的心理帮助机制,在实施心理帮助时应更加重视AIDS患者、低学历和低收入人群。展开更多
文摘Background Generally speaking. Chinese college graduates in the fifties and sixties took Russian as their second language, and those who graduated in the seventies had no second language to speak of. Now, in the years of our Open Door Policy, they find they have to learn some English and learn it quickly. They try to learn from radio and TV and many take English courses of 4 to 6 months, with varying degree of success. Their chief stumbling blocks
文摘为了解决高比例分布式电源(distributed generation,DG)大规模并网后实时量测数目缺失、传统预测辅助状态估计方法(forecasting-aided state estimation,FASE)估计精度有限等问题,提出了基于改进Crossformer伪量测构建的主动配电网FASE方法。首先,基于最大信息系数法(maximal information coefficient,MIC)筛选出高相关性的输入特征,提高预测模型的精度;然后,通过全变差正则化技术(total variation regularized,TV)优化鲁棒主成分分析法(robust principal component analysis,RPCA),构建TRPCA层,并将其嵌入到Crossformer中,以填补Crossformer无法有效处理非高斯噪声的空白;最后,利用改进的预测模型进行超短期负荷预测,经潮流计算得到节点伪量测,在量测不足情况下补全缺失数据,并结合扩展卡尔曼滤波器(extended Kalman filter,EKF)进行状态估计。在IEEE 33节点和IEEE 118节点标准配电网上进行仿真测试,结果表明所提方法在估计精度和鲁棒性等方面具有一定优势,可为主动配电网FASE提供参考。
文摘目的了解农村HIV感染者/AIDS患者(people living with HIVand AIDS,PLWHA)的心理健康状况。方法采用一般情况调查表和症状自评量表(SCL-90)对192例HIV/AIDS人员进行调查。结果192例PLWHA人员SCL-90总分、阳性项目数和各因子分均高于中国常模(各项P<0.05);心理问题阳性检出率83.9%;AIDS患者总分、阳性因子数、各因子分均显著高于HIV感染者(P<0.01);不同文化程度分组之间SCL-90各个因子的比较,除抑郁因子外,其他因子均有显著差异(P<0.05);不同经济收入之间有显著差异,接受政府救济才能维持基本开支组显著高于不需救济组(P<0.01)。性别、年龄、感染方式之间均无显著差异。结论被调查的HIV/AIDS人群存在突出的心理健康问题,应建立便捷有效的心理帮助机制,在实施心理帮助时应更加重视AIDS患者、低学历和低收入人群。
