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Prediction-based event-triggered identification of quantized input FIR systems with quantized output observations

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Science China(Information Sciences) 2020年第1期63卷 140-151页

作者： Jin GUO Jing-Dong DIAO School of Automation and Electrical Engineering University of Science and Technology Beijing Key laboratory of Knowledge Automation for industrial processes Ministry of Education

This paper addresses the identification of finite impulse response(FIR) systems with both quantized and event-triggered observations. An event-triggered communication scheme for the binary-valued output quantization is introduced to save communication resources. Combining the empirical-measure-based identification technique and the weighted least-squares optimization, an algorithm is proposed to estimate the unknown parameter by full use of the received data and the not-triggered condition. Under quantized inputs, it is shown that the estimate can strongly converge to the real values and the estimator is asymptotically efficient in terms of the Cram′er-Rao lower bound. Further, the limit of the average communication rate is derived and the tradeoff between this limit and the estimation performance is discussed. Moreover, the case of multi-threshold quantized observations is considered. Numerical examples are included to illustrate the obtained main results.

关键词： identification FIR systems prediction-based event-triggered communication quantized observations convergence performance

Suboptimal adaptive tracking control for FIR systems with binary-valued observations

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Science China(Information Sciences) 2021年第7期64卷 37-47页

作者： Xiangquan LI Zhengguang XU Jiarui CUI Lixin ZHANG School of Automation and Electrical Engineering University of Science and Technology Beijing Key laboratory of Knowledge Automation for industrial processes Ministry of Education

In this paper, we investigate and analyze the suboptimal adaptive control for finite impulse response(FIR) systems with binary-valued observations. As the parameters of FIR systems are unknown and the measurable observations can only provide limited information, we propose and analyze a two-segment design method of an adaptive control law. First, we divide the system running time axis into many sections;each of these sections is divided into two segments. During the short segment, we design the system inputs for estimating parameters. Thus, we employ the empirical-measure-based technique for designing the identification algorithm. Second, we introduce a tracking control law to track a given target based on the system parameter estimates obtained in the short segment. We achieve this using the certainty equivalent principle in the long segment. As the length of short segments tends to infinity, we observe that the parameter estimation algorithm is consistent. However, when the length of segments tends to infinity, we find that the adaptive tracking control law is asymptotically suboptimal. Finally, we demonstrate the efficiency of the two-segment design method using the simulation results.

关键词： parameter identification FIR systems binary-valued observations asymptotically suboptimal tracking adaptive control

Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex promotes intestinal development as a new iron supplement

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Science China Life Sciences 2025年第1期 219-231页

作者： Yingying Feng Yuying Wu Jialu Wang Zhenglin Dong Qian Yu Shuangshuang Xia Chunxue Liu Haihua Wang Xin Wu Tianjin Institute of industrial Biotechnology Chinese Academy of Sciences CAS Key laboratory of Agro-ecological processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of Sciences ANYOU Biotechnology Group Co.Ltd Qingdao Seawin Biotech Group Co. LTD

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron(Ⅲ) complexes(PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe(Ⅲ) complex(EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase(MLCK)/phosphorylated myosin light chain(p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S r RNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides＿fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

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2D phosphides heterostructures on titanium microfiltration membrane for enhanced ampere-level current density overall seawater splitting

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Nano Research 2025年第1期18卷 249-259页

作者： Wenjing Dai Xin Wang Yulong Ma Sisi He Ming Chen Zhaohui Yin Shuheng Tian Maolin Wang Shixiang Yu Hang Zhang Yuanzhe Wang Hong Wang Jianxin Li Faming Gao Bowen Cheng Yun Wang Zhen Yin Ding Ma Tianjin Key laboratory of Brine Chemical Engineering and Resource Eco-utilization College of Chemical Engineering and Materials ScienceTianjin University of Science and TechnologyTianjin 300457China State Key laboratory of Biobased Fiber Manufacturing Technology Tianjin University of Science and TechnologyTianjin 300457China Haian Institute of High-Tech Research Nanjing UniversityHaian 226600China Beijing National laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key laboratory of Separation Membranes and Membrane processes Separation Membrane Science and Technology International Joint Research CentreTiangong UniversityTianjin 300387China Centre for Catalysis and Clean Energy School of Environment and ScienceGold Coast CampusGriffith UniversitySouthportQueensland 4222Australia

The advancement of direct seawater electrolysis is a significant step towards sustainable hydrogen production,addressing the critical need for renewable energy sources and efficient resource ***,direct seawater electrolysis has to face several challenges posed by the corrosiveness of highly concentrated chloride and the competitive chlorine evolution reaction(ClER).To overcome these issues,we designed a novel NiP_(2)@CoP electrocatalyst on a porous titanium microfiltration(Ti MF)*** obtained bifunctional NiP_(2)@CoP catalyst outperforms the Pt/C and IrO_(2),as evidenced by its low overpotentials of 192 and 425 mV at a current density of 500 mA·cm^(-2) for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline seawater(1 M KOH+0.5 M NaCl),***,only 231 and 569 mV overpotentials are required at the current density of 1500 mA·cm^(-2) towards HER and OER in alkaline seawater,*** importantly,no ClER was observed,demonstrating its excellent selectivity to *** selection of porous Ti MF membrane as an electrode substrate further enhances the performance by providing a robust structure that promotes the fast generation and release of gas *** promising outcomes obtained with NiP_(2)@CoP catalysts on Ti MF support,therefore,pave the way for the commercial viability of direct seawater electrolysis technologies at industrial-level current densities.

关键词： direct seawater electrolysis porous titanium microfiltration membrane phosphides heterostructures NiP_(2)@CoP electrocatalyst excellent selectivity to oxygen evolution reaction(OER)

Observer-Based Path Tracking Controller Design for Autonomous Ground Vehicles With Input Saturation

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 749-761页

作者： Heng Wang Tengfei Zhang Xiaoyu Zhang Qing Li School of Automation and Electrical Engineering and also with the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China School of Automation and Electrical Engineering and also with the Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083

This paper investigates the problem of path tracking control for autonomous ground vehicles(AGVs),where the input saturation,system nonlinearities and uncertainties are ***,the nonlinear path tracking system is formulated as a linear parameter varying(LPV)model where the variation of vehicle velocity is taken into ***,considering the noise effects on the measurement of lateral offset and heading angle,an observer-based control strategy is proposed,and by analyzing the frequency domain characteristics of the derivative of desired heading angle,a finite frequency H_∞index is proposed to attenuate the effects of the derivative of desired heading angle on path tracking ***,sufficient conditions are derived to guarantee robust H_∞performance of the path tracking system,and the calculation of observer and controller gains is converted into solving a convex optimization ***,simulation examples verify the advantages of the control method proposed in this paper.

关键词： Autonomous ground vehicles(AGVs) H_∞index input saturation observer-based controller path tracking control

Second Order Sliding Mode Control for Discrete Decouplable Multivariable Systems via Input-output Models

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International Journal of Automation and computing 2015年第6期12卷 630-638页

作者： Houda Romdhane Khadija Dehri Ahmed Said Nouri Numerical Control of industrial processes National Engineering School of Gabes University of Gabes

The problem of the chattering phenomenon is still the main drawback of the classical sliding mode control. To resolve this problem, a discrete second order sliding mode control via input-output model is proposed in this paper. The proposed control law is synthesized for decouplable multivariable systems. A robustness analysis of the proposed discrete second order sliding mode control is carried out. Simulation results are presented to illustrate the effectiveness of the proposed strategy.

关键词： Discrete second order sliding mode control decoupl

Predictive Control Based on Fuzzy Supervisor for PWARX Hybrid Model

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International Journal of Automation and computing 2019年第5期16卷 683-695页

作者： Olfa Yahya Zeineb Lassoued Kamel Abderrahim Numerical Control of industrial processes National Engineering School of Gabes University of Gabes

In this paper, the problem of hybrid model predictive control(HMPC) strategy based on fuzzy supervisor for piecewise autoregressive with exogenous input(PWARX) models is addressed. We first represent the nonlinear behavior of the system with a PWARX model. Then, we transform the obtained PWARX model into a mixed logical dynamic(MLD) model in order to apply the proposed predictive control which is able to stabilize such systems along desired reference trajectories while satisfying operating ***, we propose to introduce a fuzzy supervisor allowing the readjustment of the HMPC tuning parameters in order to maintain the desired performance. Simulation and experimental results are presented to illustrate the effectiveness of the proposed approach.

关键词： Nonlinear control hybrid systems mixed logical dynamic(MLD) model predictive control fuzzy supervisor

A New Sliding Function for Discrete Predictive Sliding Mode Control of Time Delay Systems

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International Journal of Automation and computing 2013年第4期10卷 288-295页

作者： Abdennebi Nizar Ben Mansour Houda Nouri Ahmed Said Numerical Control of industrial processes National Engineering School of Gabes University of Gabes

The control of time delay systems is still an open area for research. This paper proposes an enhanced model predictive discrete-time sliding mode control with a new sliding function for a linear system with state delay. Firstly, a new sliding function including a present value and a past value of the state, called dynamic surface, is designed by means of linear matrix inequalities （LMIs）. Then, using this dynamic function and the rolling optimization method in the predictive control strategy, a discrete predictive sliding mode controller is synthesized. This new strategy is proposed to eliminate the undesirable effect of the delay term in the closed loop system. Also, the designed control strategy is more robust, and has a chattering reduction property and a faster convergence of the system s state. Finally, a numerical example is given to illustrate the effectiveness of the proposed control.

关键词： State time delay systems discrete sliding mode control model predictive control dynamic sliding function linear matrix inequalities (LMIs) chattering.

Saturated Adaptive Output-Constrained Control of Cooperative Spacecraft Rendezvous and Docking

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1462-1470页

作者： Liang Sun IEEE the Key laboratory of Knowledge Automation for industrial processes Ministry of Education School of Automation and Electrical Engineering and also with the Institute of Artificial Intelligence University of Science and Technology Beijing

This paper investigates the robust relative pose control for spacecraft rendezvous and docking with constrained relative pose and saturated control inputs.A barrier Lyapunov function is used to ensure the constraints of states,so that the computational singularity of the inverse matrix in control command can be avoided,while a linear auxiliary system is introduced to handle with the adverse effect of actuator *** tuning rules for designing parameters in control command and auxiliary system are derived based on the stability analysis of the closed-loop *** is proved that all closed-loop signals always keep bounded,the prescribed constraints of relative pose tracking errors are never violated,and the pose tracking errors ultimately converge to small neighborhoods of *** experiments validate the performance of the proposed robust saturated control strategy.

关键词： Output-constrained control pose tracking control rendezvous and docking saturated control singularity-free control spacecraft control