Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 ...Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 region of chronic stress mice revealed cell damage. Nitric oxide content and calcium concentration were significantly increased in the hippocampus, and learning and memory functions were significantly decreased. After basic fibroblast growth factor intervention, Ca2~ overload was decreased and neuronal damage was relieved in hippocampal neurons, which improved learning and memory functions in chronic stress mice. Latency was prolonged and the number of errors was decreased in a passive avoidance test.展开更多
为精准估计光伏直流微电网故障电流参数,提升故障电流过零点预测效果,提出一种基于加权最小二乘法(weighted least squares,WLMS)算法的光伏直流微电网故障电流过零点预测方法。通过故障电流参数来估计误差平方加权值与幅度因子,确定WLM...为精准估计光伏直流微电网故障电流参数,提升故障电流过零点预测效果,提出一种基于加权最小二乘法(weighted least squares,WLMS)算法的光伏直流微电网故障电流过零点预测方法。通过故障电流参数来估计误差平方加权值与幅度因子,确定WLMS算法内步长因子的取值范围,改进WLMS算法;利用改进WLMS算法来估计故障电流参数,并依据该结果建立光伏直流微电网故障电流模型;先通过F0假设检验方法在模型内提取故障电流初始相角,再通过调整采样数据窗,令建立的故障电流模型和实际模型相同,则当故障电流初始相角超过设定阈值时,可利用该模型来预测故障电流过零点。实验结果表明:所提方法下,光伏直流微电网故障电流估计的时间常数和初始电压相角与实际结果非常接近,最大误差分别为3 ms和8°;不同故障时,均有效预测了故障电流过零点,准确率为100%;在故障电流内添加谐波后,预测过零点的稳态误差较低,最高稳态误差低于24 A。展开更多
基金the "Eleventh Five-Year" Scientific and Technological Research Projects of the Education Department of Jilin Province, No. [2008]137
文摘Four weeks of uncertain stress was used to establish an animal model of chronic stress. Basic fibroblast growth factor was injected daily for 15 days following stress induction. Cell morphology in the hippocampal CA3 region of chronic stress mice revealed cell damage. Nitric oxide content and calcium concentration were significantly increased in the hippocampus, and learning and memory functions were significantly decreased. After basic fibroblast growth factor intervention, Ca2~ overload was decreased and neuronal damage was relieved in hippocampal neurons, which improved learning and memory functions in chronic stress mice. Latency was prolonged and the number of errors was decreased in a passive avoidance test.
文摘为精准估计光伏直流微电网故障电流参数,提升故障电流过零点预测效果,提出一种基于加权最小二乘法(weighted least squares,WLMS)算法的光伏直流微电网故障电流过零点预测方法。通过故障电流参数来估计误差平方加权值与幅度因子,确定WLMS算法内步长因子的取值范围,改进WLMS算法;利用改进WLMS算法来估计故障电流参数,并依据该结果建立光伏直流微电网故障电流模型;先通过F0假设检验方法在模型内提取故障电流初始相角,再通过调整采样数据窗,令建立的故障电流模型和实际模型相同,则当故障电流初始相角超过设定阈值时,可利用该模型来预测故障电流过零点。实验结果表明:所提方法下,光伏直流微电网故障电流估计的时间常数和初始电压相角与实际结果非常接近,最大误差分别为3 ms和8°;不同故障时,均有效预测了故障电流过零点,准确率为100%;在故障电流内添加谐波后,预测过零点的稳态误差较低,最高稳态误差低于24 A。
