该文研究孤岛交流微电网二次电压和频率的固定时间精确控制问题,基于多智能体一致性方法,提出考虑状态受限的自适应模糊固定时间二次电压控制器和基于控制障碍函数的二次频率控制器。在多智能体一致性控制中,将每一个分布式电源视为一...该文研究孤岛交流微电网二次电压和频率的固定时间精确控制问题,基于多智能体一致性方法,提出考虑状态受限的自适应模糊固定时间二次电压控制器和基于控制障碍函数的二次频率控制器。在多智能体一致性控制中,将每一个分布式电源视为一个非线性智能体,智能体之间通过稀疏网络进行通信。在电压控制器设计中,采用反馈线性化后未知变量的自适应模糊估计提高控制器的自适应能力,并引入新的滑模面使电压控制器在固定时间内收敛。考虑到系统状态受限问题,分别采用障碍Lyapunov函数和控制障碍函数设计电压与频率控制器,使系统状态在预设的约束范围内。频率控制器的设计还考虑了有功功率的精确分配问题,给出了严格的固定时间收敛及稳定性证明。在Matlab/Sim Power System环境下,对微电网负载变化及大干扰下的仿真验证了所提控制器的有效性。展开更多
现有结合特征提取与预测模型的方法不能准确把握金融时间序列的混沌性与交互性,导致预测精度不高。针对此问题,提出一种基于二次分解与长短期记忆(long short term memory,LSTM)网络的金融时间序列预测算法。使用变分模态分解方法与集...现有结合特征提取与预测模型的方法不能准确把握金融时间序列的混沌性与交互性,导致预测精度不高。针对此问题,提出一种基于二次分解与长短期记忆(long short term memory,LSTM)网络的金融时间序列预测算法。使用变分模态分解方法与集成经验模态分解方法依次解析金融时间序列数据,得到能表达数据混沌性特征的模态;将模态信息输入到融合有因子分解机(factorization machine,FM)的长短期记忆网络模型中,融合获取到的长记忆性特征与交互性特征,进而预测最终的结果;选取沪深300指数的历史数据作为实验数据集,通过多组对比实验验证算法的有效性。实验结果表明,提出的算法可以有效提升模型的预测能力,同时表达金融时间序列的混沌性、长记忆性、交互性。展开更多
Objective.: The objective of this study was to identify independent prognostic factors for survival in patients with epithelial ovarian cancer who had persistent disease identified at second look surgery. Methods.: We...Objective.: The objective of this study was to identify independent prognostic factors for survival in patients with epithelial ovarian cancer who had persistent disease identified at second look surgery. Methods.: We performed a retrospective chart review of all patients with epithelial ovarian cancer who had positive findings at second-look surgery between June 1991 and June 2002. All patients achieved a complete clinical remission after a prescribed course of primary therapy. Survival was determined from the time of second-look surgery until last follow-up or death. Results.: The study included a total of 262 patients, with a median age of 54 years(range, 22-80). Of the 262 patients, 166(63%) had died of disease. Records of initial(salvage) treatment after the positive second-look surgery were available for 243 patients. Therapies included the following: intraperitoneal(IP) cisplatin, 71(29%); IP cisplatin combined with a second drug, 53(22%); IP therapy other than cisplatin, 29(12%); intravenous(IV) chemotherapy, 50(21%); IP and IV therapy, 35(14%); and oral chemotherapy, 5(2%). Of the 13 potential prognostic factors analyzed, only 2 factors emerged that, when combined, were significant-residual disease after primary surgery and size of persistent disease found at second-look surgery. Patients with ≤1 cm residual disease after primary surgery and microscopic disease at second-look surgery had significantly improved survival. Conclusion.: In our analysis, the only prognostic factor for survival in patients with positive second-look procedures was a combination of residual disease after primary surgery and size of persistent disease identified at second-look surgery. No individual chemotherapy treatment imparted a survival advantage. Novel that therapeutic approaches are needed in this setting.展开更多
文摘该文研究孤岛交流微电网二次电压和频率的固定时间精确控制问题,基于多智能体一致性方法,提出考虑状态受限的自适应模糊固定时间二次电压控制器和基于控制障碍函数的二次频率控制器。在多智能体一致性控制中,将每一个分布式电源视为一个非线性智能体,智能体之间通过稀疏网络进行通信。在电压控制器设计中,采用反馈线性化后未知变量的自适应模糊估计提高控制器的自适应能力,并引入新的滑模面使电压控制器在固定时间内收敛。考虑到系统状态受限问题,分别采用障碍Lyapunov函数和控制障碍函数设计电压与频率控制器,使系统状态在预设的约束范围内。频率控制器的设计还考虑了有功功率的精确分配问题,给出了严格的固定时间收敛及稳定性证明。在Matlab/Sim Power System环境下,对微电网负载变化及大干扰下的仿真验证了所提控制器的有效性。
文摘现有结合特征提取与预测模型的方法不能准确把握金融时间序列的混沌性与交互性,导致预测精度不高。针对此问题,提出一种基于二次分解与长短期记忆(long short term memory,LSTM)网络的金融时间序列预测算法。使用变分模态分解方法与集成经验模态分解方法依次解析金融时间序列数据,得到能表达数据混沌性特征的模态;将模态信息输入到融合有因子分解机(factorization machine,FM)的长短期记忆网络模型中,融合获取到的长记忆性特征与交互性特征,进而预测最终的结果;选取沪深300指数的历史数据作为实验数据集,通过多组对比实验验证算法的有效性。实验结果表明,提出的算法可以有效提升模型的预测能力,同时表达金融时间序列的混沌性、长记忆性、交互性。
文摘Objective.: The objective of this study was to identify independent prognostic factors for survival in patients with epithelial ovarian cancer who had persistent disease identified at second look surgery. Methods.: We performed a retrospective chart review of all patients with epithelial ovarian cancer who had positive findings at second-look surgery between June 1991 and June 2002. All patients achieved a complete clinical remission after a prescribed course of primary therapy. Survival was determined from the time of second-look surgery until last follow-up or death. Results.: The study included a total of 262 patients, with a median age of 54 years(range, 22-80). Of the 262 patients, 166(63%) had died of disease. Records of initial(salvage) treatment after the positive second-look surgery were available for 243 patients. Therapies included the following: intraperitoneal(IP) cisplatin, 71(29%); IP cisplatin combined with a second drug, 53(22%); IP therapy other than cisplatin, 29(12%); intravenous(IV) chemotherapy, 50(21%); IP and IV therapy, 35(14%); and oral chemotherapy, 5(2%). Of the 13 potential prognostic factors analyzed, only 2 factors emerged that, when combined, were significant-residual disease after primary surgery and size of persistent disease found at second-look surgery. Patients with ≤1 cm residual disease after primary surgery and microscopic disease at second-look surgery had significantly improved survival. Conclusion.: In our analysis, the only prognostic factor for survival in patients with positive second-look procedures was a combination of residual disease after primary surgery and size of persistent disease identified at second-look surgery. No individual chemotherapy treatment imparted a survival advantage. Novel that therapeutic approaches are needed in this setting.
