With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation sa...With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss.展开更多
The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by ass...The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by assembly programs, an integrated control of all the ele-ments is fulfilled. The distinguishing point of the method is that the maximum control output canbe obtained with the least input information. Hence it is the optimum for the conversion of com-bination states. Finally, a thared rotary valve is designed, and it is the simplest with only onegroup of control holes.展开更多
Objective: To compare the effects of total intravenous anesthesia and static aspiration combined general anesthesia on postoperative cognitive function and psychological state of elderly esophageal cancer patients. Me...Objective: To compare the effects of total intravenous anesthesia and static aspiration combined general anesthesia on postoperative cognitive function and psychological state of elderly esophageal cancer patients. Methods: From July 2020 to April 2021, 180 elderly patients who underwent radical esophageal cancer surgery in our hospital were randomly divided into 90 cases in the control group and 90 in the observation group. The control group used static aspiration compound general anesthesia, and the patients in the observation group used intravenous anesthesia to compare the cognitive function and psychological state of the two groups of patients. Results: There was no statistical difference in the cognitive function score of patients in the observation group 30 minutes before anesthesia, 1 h and 24 hours after anesthesia compared with that in the control group, P > 0.05;there was no statistical difference between the Hamilton Anxiety Scale (HAMA) scores 30 minutes before and 24 hours after anesthesia in the observation group compared with the control group, P > 0.05;the cognitive function score of patients in the observation group of 4 h after surgery and 12 h after operation was significantly higher than that of the control group;the HAMA scores of patients in the observation group of 1 h, 4 h and 12 h after surgery were significantly lower than that of the control group, P Conclusion: The application of total intravenous anesthesia in elderly patients with esophageal cancer surgery can reduce the impact of anesthesia on their cognitive function and psychological state, which is worth popularizing and applying in clinical practice.展开更多
We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single ...We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.展开更多
The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the ...The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the excitation energies and absorption spectra of zigzag tubes（11,0） and（10,0） show opposite trends with the strain under the action of the magnetic field. For the（11,0） tube, the excitation energy decreases with the increasing uniaxial strain, with a splitting appearing in the absorption spectra. For the（10,0） tube, the variation trend firstly increases and then decreases, with a reversal point appearing in the absorption spectra. More interesting,at the reversal point the intensity of optical absorption is the largest because of the degeneracy of the two bands nearest to the Fermi Level, which is expected to be observed in the future experiment. The similar variation trend is also exhibited in the binding energy for the two kinds of semiconducting tubes.展开更多
基于行驶轨迹全球导航卫星系统(GNSS)数据,提出了出租车运动学片段提取规则和方法。根据主成分分析(PCA)及累积贡献率,确定了8个表征运动学片段的关键指标;结合K‒均值聚类算法,挖掘出租车运动特征模式。为了确保运动特征模式关键指标权...基于行驶轨迹全球导航卫星系统(GNSS)数据,提出了出租车运动学片段提取规则和方法。根据主成分分析(PCA)及累积贡献率,确定了8个表征运动学片段的关键指标;结合K‒均值聚类算法,挖掘出租车运动特征模式。为了确保运动特征模式关键指标权重的客观合理性,采用考虑指标关联性的CRITIC(criteria importance through intercriteria correlation)法和考虑指标离散程度的熵权法,构建了基于纳什均衡的组合赋权的多准则妥协解排序(VIKOR)评价模型,用于多时空情景下出租车运动特征模式评价和出租车行驶状态研判。结果表明,基于纳什均衡的组合赋权法可以有效融合CIRTIC法与熵权法对评价指标的优势,获得更合理的权重系数。就安全性、效率和舒适性而言,出租车行驶状态在主干路和次干路上优于在支路上。早高峰出租车行驶安全性最佳,平峰和晚高峰相对一般。展开更多
传统电动汽车充电负荷建模通常采用对电动汽车个体进行抽样模拟的方式,未能从分析机理的角度描述电动汽车群体相互作用形成的宏观运行状态。为此,提出一种基于半动态交通均衡模型和组合荷电状态(combined states of the charge,CSOC)概...传统电动汽车充电负荷建模通常采用对电动汽车个体进行抽样模拟的方式,未能从分析机理的角度描述电动汽车群体相互作用形成的宏观运行状态。为此,提出一种基于半动态交通均衡模型和组合荷电状态(combined states of the charge,CSOC)概率计算的电动汽车充电负荷概率分布计算方法。首先,分析电动汽车的交通特性和充电特性,并提出一种可行路径集构建方法;然后,引入交通均衡理论进行电动汽车空间分布建模,建立考虑随机效用的半动态交通均衡模型,实现宏观交通流均衡分配。进一步地,从理论层面分析电动汽车群的荷电状态变化,建立基于CSOC的充电负荷概率分布计算模型。最后,分别在13节点路网和实际大路网中验证所提方法的有效性,并分析了电动汽车渗透率和路网结构对充电负荷概率分布的影响。展开更多
基金supported in part by the Guangxi Power Grid Company’s 2023 Science and Technol-ogy Innovation Project(No.GXKJXM20230169)。
文摘With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss.
文摘The theory of shared control combines organically the control of every controlled ele-ments and with it all the controlled elements share the same control element. Applying theschemes of shared control searched by assembly programs, an integrated control of all the ele-ments is fulfilled. The distinguishing point of the method is that the maximum control output canbe obtained with the least input information. Hence it is the optimum for the conversion of com-bination states. Finally, a thared rotary valve is designed, and it is the simplest with only onegroup of control holes.
文摘Objective: To compare the effects of total intravenous anesthesia and static aspiration combined general anesthesia on postoperative cognitive function and psychological state of elderly esophageal cancer patients. Methods: From July 2020 to April 2021, 180 elderly patients who underwent radical esophageal cancer surgery in our hospital were randomly divided into 90 cases in the control group and 90 in the observation group. The control group used static aspiration compound general anesthesia, and the patients in the observation group used intravenous anesthesia to compare the cognitive function and psychological state of the two groups of patients. Results: There was no statistical difference in the cognitive function score of patients in the observation group 30 minutes before anesthesia, 1 h and 24 hours after anesthesia compared with that in the control group, P > 0.05;there was no statistical difference between the Hamilton Anxiety Scale (HAMA) scores 30 minutes before and 24 hours after anesthesia in the observation group compared with the control group, P > 0.05;the cognitive function score of patients in the observation group of 4 h after surgery and 12 h after operation was significantly higher than that of the control group;the HAMA scores of patients in the observation group of 1 h, 4 h and 12 h after surgery were significantly lower than that of the control group, P Conclusion: The application of total intravenous anesthesia in elderly patients with esophageal cancer surgery can reduce the impact of anesthesia on their cognitive function and psychological state, which is worth popularizing and applying in clinical practice.
基金supported in part by the Japan Ministry of Education,Sciences and Culture under Grants-in-Aid for Scientific Research(C)(21560471)the Green Industry Leading Program of Hubei University of Technology(CPYF2017003)the National Natural Science Foundation of China(1160147411461082)
文摘We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.
基金Supported by the National Natural Science Foundation of China under Grant No 11304378the Fundamental Research Funds for the Central Universities under Grant No 2017XKQY093
文摘The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the excitation energies and absorption spectra of zigzag tubes（11,0） and（10,0） show opposite trends with the strain under the action of the magnetic field. For the（11,0） tube, the excitation energy decreases with the increasing uniaxial strain, with a splitting appearing in the absorption spectra. For the（10,0） tube, the variation trend firstly increases and then decreases, with a reversal point appearing in the absorption spectra. More interesting,at the reversal point the intensity of optical absorption is the largest because of the degeneracy of the two bands nearest to the Fermi Level, which is expected to be observed in the future experiment. The similar variation trend is also exhibited in the binding energy for the two kinds of semiconducting tubes.
文摘基于行驶轨迹全球导航卫星系统(GNSS)数据,提出了出租车运动学片段提取规则和方法。根据主成分分析(PCA)及累积贡献率,确定了8个表征运动学片段的关键指标;结合K‒均值聚类算法,挖掘出租车运动特征模式。为了确保运动特征模式关键指标权重的客观合理性,采用考虑指标关联性的CRITIC(criteria importance through intercriteria correlation)法和考虑指标离散程度的熵权法,构建了基于纳什均衡的组合赋权的多准则妥协解排序(VIKOR)评价模型,用于多时空情景下出租车运动特征模式评价和出租车行驶状态研判。结果表明,基于纳什均衡的组合赋权法可以有效融合CIRTIC法与熵权法对评价指标的优势,获得更合理的权重系数。就安全性、效率和舒适性而言,出租车行驶状态在主干路和次干路上优于在支路上。早高峰出租车行驶安全性最佳,平峰和晚高峰相对一般。
文摘传统电动汽车充电负荷建模通常采用对电动汽车个体进行抽样模拟的方式,未能从分析机理的角度描述电动汽车群体相互作用形成的宏观运行状态。为此,提出一种基于半动态交通均衡模型和组合荷电状态(combined states of the charge,CSOC)概率计算的电动汽车充电负荷概率分布计算方法。首先,分析电动汽车的交通特性和充电特性,并提出一种可行路径集构建方法;然后,引入交通均衡理论进行电动汽车空间分布建模,建立考虑随机效用的半动态交通均衡模型,实现宏观交通流均衡分配。进一步地,从理论层面分析电动汽车群的荷电状态变化,建立基于CSOC的充电负荷概率分布计算模型。最后,分别在13节点路网和实际大路网中验证所提方法的有效性,并分析了电动汽车渗透率和路网结构对充电负荷概率分布的影响。
