This paper deals with the problem of iterative learning control for a class of linear continuous-time switched systems in the presence of a fixed initial shift. Here, the considered switched systems are operated durin...This paper deals with the problem of iterative learning control for a class of linear continuous-time switched systems in the presence of a fixed initial shift. Here, the considered switched systems are operated during a finite time interval repetitively. According to the characteristics of the systems, a PD-type learning scheme is proposed for such switched systems with arbitrary switching rules, and the corresponding output limiting trajectories under the action of the PD-type learning scheme are given. Based on the contraction mapping method, it is shown that this scheme can guarantee the outputs of the systems converge uniformly to the output limiting trajectories of the systems over the whole time interval. Furthermore, the initial rectifying strategies are applied to the systems for eliminating the effect of the fixed initial shift. When the learning scheme is applied to the systems, the outputs of the systems can converge to the desired reference trajectories over a pre-specified interval. Finally, simulation examples illustrate the effectiveness of the proposed method.展开更多
In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical challenge.To overcome this challenge,the triboelectric nano...In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical challenge.To overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in 2012.This device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)signals.However,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)signals.In recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require solutions.In this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air breakdown.Their typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are identified.Furthermore,the applications of DC-TENGs in various scenarios are summarized.Finally,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.展开更多
To protect the environment and its domestic industries from excess production,China must guide the non-ferrous metal industry In an effort to save energy and curb carbon emissions, in addition to reorganizing a curren...To protect the environment and its domestic industries from excess production,China must guide the non-ferrous metal industry In an effort to save energy and curb carbon emissions, in addition to reorganizing a currently disorderly industry, China will continue to control展开更多
基金The NSF(11371013)of Chinathe Research Innovation Program(SKCX17 032)for Graduate Students
文摘This paper deals with the problem of iterative learning control for a class of linear continuous-time switched systems in the presence of a fixed initial shift. Here, the considered switched systems are operated during a finite time interval repetitively. According to the characteristics of the systems, a PD-type learning scheme is proposed for such switched systems with arbitrary switching rules, and the corresponding output limiting trajectories under the action of the PD-type learning scheme are given. Based on the contraction mapping method, it is shown that this scheme can guarantee the outputs of the systems converge uniformly to the output limiting trajectories of the systems over the whole time interval. Furthermore, the initial rectifying strategies are applied to the systems for eliminating the effect of the fixed initial shift. When the learning scheme is applied to the systems, the outputs of the systems can converge to the desired reference trajectories over a pre-specified interval. Finally, simulation examples illustrate the effectiveness of the proposed method.
基金supported by the Postdoctoral Science Foundation(Grant No.2023M730419)the Ministry of Education“Chunhui Plan”Cooperative Scientific Research Project(Grant No.HZKY20220206)+2 种基金the Scientific and Technology Research Program of Chongqing Municipal Education Commission(Grant Nos.KJQN202100522,KJQN202200514 and KJQN202100514)the Natural Science Foundation of Chongqing(Grant No.cstc2021jcyj-msxmX0746)the Dr.“Through Train”Scientific Research Program(Grant No.CSTB2022BSXM-JCX0091)。
文摘In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical challenge.To overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in 2012.This device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)signals.However,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)signals.In recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require solutions.In this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air breakdown.Their typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are identified.Furthermore,the applications of DC-TENGs in various scenarios are summarized.Finally,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.
文摘To protect the environment and its domestic industries from excess production,China must guide the non-ferrous metal industry In an effort to save energy and curb carbon emissions, in addition to reorganizing a currently disorderly industry, China will continue to control