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Enhanced adaptive nonlinear extended state observer for pure feedback systems with matched and mismatched disturbances
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作者 Mahtab Delpasand Mohammad Farrokhi 《Control Theory and Technology》 EI CSCD 2024年第2期254-268,共15页
In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a n... In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature. 展开更多
关键词 Nonlinear extended state observer enhanced adaptive extended state observer Adaptation law Multiple-channel disturbances Inverted pendulum system Time-varying gain
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Ag3PO4 Microcrystals Synthesized by Room-Temperature Solid State Reaction:Enhanced Photocatalytic Activity and Photoelectronchemistry Performance
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作者 郝辰春 许杰 +5 位作者 施洪龙 付军丽 邹斌 孟杉 王文忠 贾莹 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期152-155,共4页
Ag3PO4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the a... Ag3PO4 microcrystals with highly enhanced visible light photocatalytic activity are prepared by a facile and simple solid state reaction at room temperature. The composition, morphology and optical properties of the asprepared Ag3PO4 microcrystMs are characterized by x-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectra. The photocatalytie properties of Ag3PO4 are investigated by the degradation of both methylene blue and methyl orange dyes under visible light irradiation. The as-prepared Ag3PO4 microcrystals possess high photocatalytic oxygen production with the rate of 673μmolh-1g-1. Moreover, the as-prepared Ag3PO4 microcrystals show an enhanced photoelectrochemistry performance under irradiation of visible light. 展开更多
关键词 Ag Ag3PO4 Microcrystals Synthesized by Room-Temperature Solid state Reaction:enhanced Photocatalytic Activity and Photoelectronchemistry Performance PO
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Simulation of Intermediate State Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field
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作者 Wen-Jing Cheng Shi-Hua Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第11期23-27,共5页
We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photo... We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^(3+)ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system. 展开更多
关键词 ab Simulation of Intermediate state Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field
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Enhanced population of excited single state strategy:Irradiation and ultrasound dual-response and host tumor-driven nanosensitizers construction in triple synergistic therapy
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作者 Yaning Li Mengyan Tian +5 位作者 Tianyue Yang Jiayu Cao Hongli Chen Jun Guo Pai Liu Yi Liu 《Nano Research》 SCIE EI CSCD 2024年第6期5501-5511,共11页
Phototheranostics is an emerging field in synergistic antitumor therapy in which irradiation and sensitizers are combined to produce reactive oxygen species(ROS),bio-images,and high temperatures.All of these are arriv... Phototheranostics is an emerging field in synergistic antitumor therapy in which irradiation and sensitizers are combined to produce reactive oxygen species(ROS),bio-images,and high temperatures.All of these are arrived from the energy of sensitizers,which located in excited single state(S_(1)).Undeniably,the decentralization of the S_(1)population indirectly decreases the effect of each individual treatment.In this study,a strategy was proposed for enhancing the S_(1)population,and a sensitizer with mitochondrial targeting property,1,4-indolyl iodinated pyrrolo[3,2-b]pyrrole derivative(2I-TPIS),was assembled into adenosine triphosphate(ATP)-responsive nanoparticles(DPA-2I NPs)to achieve dual responses to irradiation and ultrasonication(US)for application to photo-sonodynamic therapy(PSDT).Compared with monotherapies,2I-TPIS generated more ROS in PSDT,inducing mitochondrial autophagy and apoptosis,which in turn triggered immunogenic cell death(ICD).Subsequently,DPA-2I NPs were constructed and self-assembled with the chemotherapeutic agents DPA-Cd and 2I-TPIS to achieve a triple synergistic strategy involving chemotherapy(CT)and PSDT.DPA-2I NPs exhibited absolute sensitization,intra-tumoral overexpression of ATP,and disassembly.Importantly,the biosafety and potent antitumor efficiency of the DPA-2I NP-based“PSDT+CT”therapy were revealed using a 4T1 tumor model.The study results provide insights into the design of sensitizers possessing a sufficient S_(1)population and a highly efficient tumor ablation capacity derived from molecular structural modulation,further enabling triple synergistic antitumor therapies,and expanding the clinical application of sensitizers. 展开更多
关键词 triphosphate(ATP)-activated nano-sensitizers photo-sonodynamic therapy aggregation-induced emission enhanced excited state population
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Digital Competitiveness in the Global South:Dual Challenges and Pathways Forward
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作者 Xu Xiujun Jin Qixuan 《China International Studies》 2025年第5期65-90,共26页
Digital technology is the most dynamic frontier of contemporary global scientific and technological advancements,serving as a central driver of today’s technological progress.Ongoing R&D and deployment of digital... Digital technology is the most dynamic frontier of contemporary global scientific and technological advancements,serving as a central driver of today’s technological progress.Ongoing R&D and deployment of digital innovative technologies have rendered international competition and cooperation increasingly complex in both implications and forms.Beyond its role in accelerating technological progress,digital technology enhances state capability by adding a digital dimension to national power.It enables states that possess comparative advantages in digital R&D and deployment to gain greater influence in shaping international discourse,thereby widening the power gap among nations. 展开更多
关键词 competition cooperation international competition technological progress global south accelerating technological progressdigital digital competitiveness enhances state capability digital technology
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