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Estimating the Delay-time for the Stability of Markovian Jump Bilinear Systems with Saturating Actuators

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自动化学报 2010年第5期36卷 762-766页

作者： KANG Yu SHANG Wei-Ke xi hong-sheng Department of Automation University of Science and Technology of China Hefei 230026 P.R. China

This paper is concerned with the stochastic stabilizability problem of time-delay Markovian jump bilinear systems with saturating *** conditions for local exponential stochastic stability of the delay-free systems with memoryless state feedback control are given, and an upperbound of time delay is provided such that the delayed system retains its stochastic stabilizability if the corresponding delay-free system is stochastic stabilizable. A numerical example is provided to demonstrate the effectiveness of the proposed approach

关键词：马尔可夫链线性系统可靠性稳定性

Robust and Non-fragile H_∞ Control for a Class of Uncertain Jump Linear Systems

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自动化学报 2006年第3期32卷 438-443页

作者： KANG Yu xi hong-sheng ZHANG Da-Li JI Hai-Bo Department of Automation University of Science and Technology of China Hefei Anhui 230026

This paper describes the synthesis of robust and non-fragile H∞ state feedback controllers for a class of uncertain jump linear systems with Markovian jumping parameters and state multiplicative noises. Under the assumption of a complete access to the norm-bounds of the system uncertainties and controller gain variations, sufficient conditions on the existence of robust stochastic stability and γ-disturbance attenuation H∞ property are presented. A key feature of this scheme is that the gain matrices of controller are only based on It, the observed projection of the current regime rt.

关键词：鲁棒控制 Markovian过程跳跃参数稳定性

Clinical significance of preoperative nutritional status in elderly gastric cancer patients undergoing radical gastrectomy:A singlecenter retrospective study

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2211-2220页

作者： xi-Ning Zhao Jing Lu hong-Yong He sheng-Jin Ge Department of Anesthesiology Zhongshan HospitalFudan UniversityShanghai 200032China Department of Nursing Zhongshan HospitalFudan UniversityShanghai 200032China Department of General Surgery/Emergency Surgery Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND The population of elderly patients with gastric cancer is increasing,which is a major public health issue in *** is one of the greatest risk factors for adverse clinical outcomes in elderly patients with gastric *** To investigate the preoperative nutritional status and its association with delayed discharge of elderly gastric cancer patients following radical *** A total of 783 patients aged 65 years and older harboring gastric adenocarcinoma and following radical gastrectomy were retrospectively analyzed from the prospectively collected database of Zhongshan Hospital of Fudan University between January 2018 and May *** The overall rate of malnutrition was 31.8%.The incidence of postoperative complications was significantly higher in the malnourished group compared to the well-nourished group(P<0.001).Nutritional characteristics in the malnourished group,including body mass index,prognostic nutritional index(PNI),albumin,prealbumin,and hemoglobin,were all significantly lower than those in the well-nourished *** percentage of patients who received postoperative total nutrient admixture was lower in the malnourished group compared to the wellnourished group(22.1%vs 33.5%,P=0.001).Age≥70 years(HR=1.216,95%CI:1.048-1.411),PNI<44.5(HR=1.792,95%CI:1.058-3.032),operation time≥160 minutes(HR=1.431,95%CI:1.237-1.656),and postoperative complications grade III or higher(HR=2.191,95%CI:1.604-2.991)were all recognized as independent risk factors associated with delayed *** Malnutrition is relatively common in elderly patients undergoing *** PNI is an independent risk factor associated with delay *** strategies are needed to improve the clinical outcome of these patients.

关键词： Gastric cancer Preoperative nutritional status Malnutrition Elderly Radical gastrectomy

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Lorenz系统族采样同步研究

物理学报 2007年第5期56卷 2488-2492页

作者：金辉宇奚宏生中国科学技术大学自动化系合肥230026

从对连续时间混沌系统进行数字测量的角度,提出了连续时间混沌系统的采样同步问题.利用控制理论的结果,设计了Lorenz系统族的采样同步系统.仅需测量一个状态分量,就可在采样时刻实现同步.数值模拟例证了同步的性能.

关键词：混沌同步 Lorenz系统族采样同步

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan Nie hong-chang Liu Yue Liu Can Wang Jin-lan xia Wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

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动态电源管理的随机切换模型与在线优化

自动化学报 2007年第1期33卷 66-71页

作者：江琦奚宏生殷保群中国科学技术大学自动化系合肥230027

考虑系统参数未知情况下的动态电源管理问题,提出一种基于强化学习的在线策略优化算法.通过建立事件驱动的随机切换分析模型,将动态电源管理问题转化为带约束的Markov决策过程的策略优化问题.利用此模型的动态结构特性,结合在线学习估... 详细信息

考虑系统参数未知情况下的动态电源管理问题,提出一种基于强化学习的在线策略优化算法.通过建立事件驱动的随机切换分析模型,将动态电源管理问题转化为带约束的Markov决策过程的策略优化问题.利用此模型的动态结构特性,结合在线学习估计梯度与随机逼近改进策略,提出动态电源管理策略的在线优化算法.随机切换模型对电源管理系统的动态特性描述精确,在线优化算法自适应性强,运算量小,精度高,具有较高的实际应用价值.

关键词：动态电源管理 Markov决策过程强化学习梯度估计随机逼近在线优化

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动态电源管理超时策略自适应优化算法

控制与决策 2008年第4期23卷 372-377页

作者：江琦奚宏生殷保群中国科学技术大学自动化系合肥230027

基于强化学习的方法,提出一种动态电源管理超时策略自适应在线优化算法.构建基于超时策略动态电源管理系统的半Markov控制过程模型,将动态电源管理问题转化为一个带约束的优化问题.利用此模型的动态结构特性,结合在线梯度估计与随机逼... 详细信息

基于强化学习的方法,提出一种动态电源管理超时策略自适应在线优化算法.构建基于超时策略动态电源管理系统的半Markov控制过程模型,将动态电源管理问题转化为一个带约束的优化问题.利用此模型的动态结构特性,结合在线梯度估计与随机逼近推导超时策略的在线优化算法.该算法自适应性强,计算量小,具有全局收敛性.通过无线网络通信节点动态电源管理的应用仿真验证了算法的有效性.

关键词：动态电源管理超时策略半Markov控制过程强化学习在线优化

连续时间MCP在紧致行动集上的最优策略(英文)

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自动化学报 2003年第2期29卷 206-211页

作者：奚宏生唐昊殷保群中国科学技术大学自动化系合肥230026

文中研究了一类连续时间Markov控制过程 (CTMCP)无穷水平平均代价性能的最优控制决策问题 .文章采用无穷小生成元和性能势的基本性质 ,直接导出了平均代价模型在紧致行动集上的最优性方程及其解的存在性定理 ,提出了求解ε 最优平稳控... 详细信息

文中研究了一类连续时间Markov控制过程 (CTMCP)无穷水平平均代价性能的最优控制决策问题 .文章采用无穷小生成元和性能势的基本性质 ,直接导出了平均代价模型在紧致行动集上的最优性方程及其解的存在性定理 ,提出了求解ε 最优平稳控制策略的数值迭代算法 ,并给出了这种算法的收敛性证明 .最后通过分析一个数值例子来说明这种方法的应用 .

关键词： MCP 紧致行动集最优策略性能势平均代价准则数值迭代算法 ε-最优平衡控制策略

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无线多媒体通信网适应带宽配置在线优化算法

软件学报 2007年第6期18卷 1491-1500页

作者：江琦奚宏生殷保群中国科学技术大学自动化系安徽合肥230027

基于强化学习的方法,提出一种无线多媒体通信网适应带宽配置在线优化算法,在满足多类业务不同QoS(quality of service)要求的同时,提高网络资源的利用率.建立事件驱动的随机切换分析模型,将无线多媒体通信网中的适应带宽配置问题转化为... 详细信息

基于强化学习的方法,提出一种无线多媒体通信网适应带宽配置在线优化算法,在满足多类业务不同QoS(quality of service)要求的同时,提高网络资源的利用率.建立事件驱动的随机切换分析模型,将无线多媒体通信网中的适应带宽配置问题转化为带约束的连续时间Markov决策问题.利用此模型的动态结构特性,结合在线学习估计梯度与随机逼近改进策略,提出适应带宽配置在线优化算法.该算法不依赖于系统参数,如呼叫到达率、呼叫持续时间等,自适应性强,计算量小,能够收敛到全局最优,适用于复杂应用环境中无线多媒体通信网适应带宽配置的在线优化.仿真实验结果验证了算法的有效性.

关键词：适应带宽配置 Markov决策过程策略优化强化学习随机逼近 QoS(quality of service)保证