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Adaptive observer-based integral event-triggered antivibration control of a full aircraft active landing gear system with irregular runway excitations

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Science China(Information Sciences) 2024年第6期67卷 248-261页

作者： Wenxiao HU chenglong du Fanbiao LI Xinmin CHEN Chunhua YANG Weihua GUI School of Automation Central South University Research Center in System Engineering for Special Aircrafts Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences

This study addresses the antivibration issue of a full aircraft active landing gear system(LGS)under landing impact and runway excitations via a novel adaptive observer-based integral event-triggered control method. First, a full aircraft active LGS comprising a front gear and two synchronized main left and right gears with active suspensions is established, where the information exchange among them is not implemented directly. Second, two adaptive observers are designed separately for the front and main LGSs to identify the varying damping parameters and estimate the system states simultaneously. Third, estimated states are transmitted to a shared network through a novel integral event-triggered mechanism(I-ETM);thus, the front and main LGSs are interconnected, and a networked control scheme for the aircraft LGS is constructed. Additionally, the integrated active control law is designed with the aid of the transmitted states of the front and main LGSs, enhancing the robustness against the pitch vibration of the aircraft.Furthermore, the L2-stability of the hybrid system is guaranteed to depress the vertical vibration effect of the landing impact and irregular runway excitations, thus improving passenger safety and comfort. Moreover,a codesign method is provided to obtain feasible solutions to the gain matrices of the observers and controllers simultaneously. Simulation and comparison results are presented to illustrate the effectiveness and superiority of the proposed control scheme in antivibration and saving communication resources.

关键词： aircraft active landing gear antivibration control integral event-triggered mechanism adaptive observer ${\mathcal{L}}_2$-stability

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Integral Event-Triggered Attack-Resilient Control of Aircraft-on-Ground Synergistic Turning System With Uncertain Tire Cornering Stiffness

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1276-1287页

作者： chenglong du Fanbiao Li Yang Shi Chunhua Yang Weihua Gui the School of Automation Central South UniversityChangsha 410083China the Department of Mechanical Engineering University of VictoriaVictoria BC V8W 3P6Canada

This article proposes an integral-based event-triggered attack-resilient control method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception attacks. First, a novel AoG synergistic turning model is established with synergistic reverse steering of the front and main wheels to decrease the steering angle of the AoG fuselage, thus reducing the steady-state error when it follows a path with some large curvature. Considering that the tire cornering stiffness of the front and main wheels vary during steering, a dynamical observer is designed to adaptively identify them and estimate the system state at the same time.Then, an integral-based event-triggered mechanism(I-ETM) is synthesized to reduce the transmission frequency at the observerto-controller end, where stochastic deception attacks may occur at any time with a stochastic probability. Moreover, an attackresilient controller is designed to guarantee that the closed-loop system is robust L2-stable under stochastic attacks and external disturbances. A co-design method is provided to get feasible solutions for the observer, controller, and I-ETM simultaneously. An optimization program is further presented to make a tradeoff between the robustness of the control scheme and the saving of communication resources. Finally, the low-and high-probability stochastic deception attacks are considered in the simulations. The results have illustrated that the AoG synergistic turning system with the proposed control method follows a path with some large curvature well under stochastic deception attacks. Furthermore,compared with the static event-triggered mechanisms, the proposed I-ETM has demonstrated its superiority in saving communication resources.

关键词： Adaptive observer aircraft-on-ground(AoG)synergistic turning attack-resilient controller integral-based event-triggered mechanism L_2-stability

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Evolution of Biofilm and Its Effect on Microstructure of Mortar Surfaces in Simulated Seawater

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 234-243页

作者：荣辉 YU chenglong 张颖 School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China Tianjin Key Laboratory of Building Green Functional Materials Tianjin Chengjian UniversityTianjin 300384China

To explore the role of biofilm formation on the corrosion of marine concrete structures, we investigated the attachment of biofilm on mortar surfaces in simulated seawater and the influence of biofilm on the microstructure of mortar surfaces. The results show that the evolution of biofilm on mortar surfaces in simulated seawater is closely related to the corrosion suffered by the mortar, and the process of biofilm attachment and shedding is continuous and cyclical. It is found that the specimens in the absence of biofilm attachment are more severely eroded internally by the corrosive medium in simulated seawater than those in the presence of biofilm attachment. For the specimens without biofilm attachment, after 60 days, gypsum forms,and after 120 days, the number of pores in the mortar is reduced. In contrast, for the specimens in the presence of biofilm attachment, gypsum could only be detected after 90 days, and fewer pores are filled. Therefore, the formation of biofilm could delay the invasion of the corrosive medium into the interior of mortar during the evolution of biofilm on mortar surfaces, mitigating the corrosion of mortars in seawater.

关键词： biofilm attachment mortar sulfur-oxidizing bacteria gypsum simulated seawater microstructure

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Nickel-Catalyzed Regiodivergent Acylzincation of Styrenes with Organozincs and CO

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Chinese Journal of Chemistry 2024年第6期42卷 599-604页

作者： chenglong Wang Ning Liu Xianqing Wu Jingping Qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China Dedicated to the Special Issue of C1 Chemistry.

Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond.Recently,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation chemistry.Herein,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization process.This protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.

关键词： Carbonylation Carbometallation Styrene Nickel Cyclization

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Extracorporeal membrane oxygenation versus cardiopulmonary bypass during transcatheter aortic valve implantation: a meta-analysis of survival benefits

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World Journal of Emergency Medicine 2024年第4期15卷 306-310页

作者： Huiruo Liu Liangshan Wang Xing Hao Zhongtao du chenglong Li Hong Wang Xiaotong Hou Centre for Cardiac Intensive Care Beijing Institute of HeartLung and Blood Vessel DiseasesBeijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Since its approval by the Food and Drug Administration in 2011,transcatheter aortic valve implantation(TAVI)has rapidly evolved to become the preferred ultimate intervention for high-and intermediate-risk patients with severe symptomatic aortic stenosis.[1]This is due to its non-open-heart,minimally invasive and off-pump advantages.[1]Nevertheless,as a result of the frequent frailty and comorbidity profiles of patients undergoing TAVI,such as advanced cardiac dysfunction and extensive coronary artery disease,or technically difficult anatomy for the procedure itself,[2-4]it is common for these patients to experience critical circulatory collapse perioperatively.These factors are linked to elevated mortality rates,necessitating suitable mechanical circulatory support(MCS)to reverse the disastrous situations.[5]

关键词： anatomy bypass elevated

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The gasdermin family:emerging therapeutic targets in diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1905-1937页

作者： chenglong Zhu Sheng Xu Ruoyu Jiang Yizhi Yu Jinjun Bian Zui Zou Faculty of Anesthesiology Changhai HospitalNaval Medical UniversityShanghai 200433China School of Anesthesiology Naval Medical UniversityShanghai 200433China National Key Laboratory of Immunity&Inflammation Naval Medical UniversityShanghai 200433China d 4 Department of Biochemistry and Molecular Biology College of Basic Medical SciencesNaval Medical UniversityShanghai 200433China

The gasdermin(GSDM)family has garnered significant attention for its pivotal role in immunity and disease as a key player in pyroptosis.This recently characterized class of pore-forming effector proteins is pivotal in orchestrating processes such as membrane permeabilization,pyroptosis,and the follow-up inflammatory response,which are crucial self-defense mechanisms against irritants and infections.GSDMs have been implicated in a range of diseases including,but not limited to,sepsis,viral infections,and cancer,either through involvement in pyroptosis or independently of this process.The regulation of GSDM-mediated pyroptosis is gaining recognition as a promising therapeutic strategy for the treatment of various diseases.Current strategies for inhibiting GSDMD primarily involve binding to GSDMD,blocking GSDMD cleavage or inhibiting GSDMD-N-terminal(NT)oligomerization,albeit with some off-target effects.In this review,we delve into the cutting-edge understanding of the interplay between GSDMs and pyroptosis,elucidate the activation mechanisms of GSDMs,explore their associations with a range of diseases,and discuss recent advancements and potential strategies for developing GSDMD inhibitors.

关键词： diseases therapeutic immunity

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Effects of the initiation position on the damage and fracture characteristics of linear-charge blasting in rock

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 443-451页

作者： Chenxi Ding Renshu Yang Xiao Guo Zhe Sui chenglong Xiao Liyun Yang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and three-dimensional reconstruction methods. The fractal damage theory was used to quantify the crack distribution and damage degree of sandstone specimens after blasting. The results showed that regardless of an inverse or top initiation, due to compression deformation and sliding frictional resistance, the plugging medium of the borehole is effective. The energy of the explosive gas near the top of the borehole is consumed. This affects the effective crushing of rocks near the top of the borehole, where the extent of damage to Sections Ⅰ and Ⅱ is less than that of Sections Ⅲ and Ⅳ. In addition, the analysis revealed that under conditions of top initiation, the reflected tensile damage of the rock at the free face of the top of the borehole and the compression deformation of the plug and friction consume more blasting energy, resulting in lower blasting energy efficiency for top initiation. As a result, the overall damage degree of the specimens in the top-initiation group was significantly smaller than that in the inverse-initiation group. Under conditions of inverse initiation, the blasting energy efficiency is greater, causing the specimen to experience greater damage. Therefore, in the engineering practice of rock tunnel cut blasting, to utilize blasting energy effectively and enhance the effects of rock fragmentation, using the inverse-initiation method is recommended. In addition, in three-dimensional(3D) rock blasting, the bottom of the borehole has obvious end effects under the conditions of inverse initiation, and the crack distribution at the bottom of the borehole is trumpet-shaped. The occurrence of an end effect in the 3D linear-charge blasting model experiment is related to the initiation position and the blocking condition.

关键词： blasting linear charge initiation position computed tomography three-dimensional reconstruction damage

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Artificial intelligence optimization and controllable slow-release iron sulfide realizes efficient separation of copper and arsenic in strongly acidic wastewater

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Journal of Environmental Sciences 2024年第5期139卷 293-307页

作者： Xingfei Zhang chenglong Lu Jia Tian Liqiang Zeng Yufeng Wang Wei Sun Haisheng Han Jianhua Kang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Centre for Mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane 4072Australia

Iron sulfide(FeS)is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S^(2-)slow-release effect.However,uncertainties arise because of the constant changes in wastewater composition,affecting the selection of operating parameters and FeS types.In this study,the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper removal.Orthogonal experiments were conducted,and the results identified the Cu/As ratio,H_(2)SO_(4) concentration,and FeS dosage as the three main factors influencing the separation efficiency.The backpropagation artificial neural network(BP-ANN)model was established to determine the relationship between the influencing factors and the separation efficiency.The correlation coefficient(R)of overall model was 0.9923 after optimizing using genetic algorithm(GA).The BP-GA model was also solved using GA under specific constraints,predicting the best solution for the separation process in real-time.The predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency,and the maximum separation factor can reached 1,400.This study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.

关键词： FeS nanoparticles Aging Sulfide precipitation Orthogonal experiment Artificial neural network Prediction

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Effect of Molecular Weight on Thermoelectric Performance of P3HT Analogues with 2-Propoxyethyl Side Chains

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 268-281页

作者：董得福 WANG Wei ZHAN Chun LI chenglong ZHOU Qisheng 肖生强 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared herein in addition with step increment of about 7 kDa on numberaverage molecular weight(M_(n))from around 11 to 32 kDa(accordingly denoted as P11k,P18k,P25k,and P32k).When doped in film by FeCl_(3)at the optimized conditions,the maximum power factor(PF_(max))increases greatly from 4.3μW·m^(-1)·K^(-2)for P11k to 8.8μW·m^(-1)·K^(-2)for P18k,and further to 9.7μW·m^(-1)·K^(-2)for P25k,followed by a slight decrease to 9.2μW·m^(-1)·K^(-2)for P32k.The close Seebeck coefficients(S)at PF_(max)are observed in these doped polymer films due to their consistent frontier orbital energy levels and Fermi levels.The main contribution to this PF_(max)evolution thus comes from the corresponding conductivities(σ).Theσvariation of the doped films can be rationally correlated with their microstructure evolution.

关键词： conjugated polymer molecular weight microstructure thermoelectric performance

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Compound events of heatwave and dust storm in the Taklamakan Desert

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Science China Earth Sciences 2024年第7期67卷 2073-2083页

作者： Yuzhi LIU Jianping HUANG Ziyuan TAN chenglong ZHOU Dan LI Yongkun XIE Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Taklamakan National Station of Observation and Research for Desert Meteorology in Xinjiang Urumqi 830002China

Taklamakan Desert(TD)has been characterized by numerous heatwaves and dust storms,leading to negative effects on societies and ecosystems at regional and global scales.However,the association between heatwaves and dust storms is poorly known.In this study,we describe the association between heatwaves and dust events and propose a mechanism for such compound events in the TD.The results show that,from 1993 to 2022,the frequency and intensity of heatwaves in the TD have increased at a rate of 0.21 days year^(-1)and 0.02℃ year^(-1),respectively.More than 40% of heatwaves existed with dust events,which significantly lagged behind heatwaves.Mechanically,the higher the air temperature,the hotter and drier the soil,leading to more dust emissions in the TD.In high-occurrence heatwave years,a large-scale wave train of“cyclone-anticyclone-cyclone”in the northwest-southeast direction was found,with the anticyclone of which hovered over the TD region.The anomalous anticyclones favored the formation and maintenance of heatwaves,and subsequent anomalous cyclones in the wave train triggered strong dust events followed by heatwaves.With climate warming,the compound events of heatwave and dust storm are becoming bigger hazards threatening the socioeconomic and ecological security in the TD,the profound study of which is critical to understanding regional extreme responses.

关键词： Heatwave dust storm Compound events Taklamakan Desert

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