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Adaptive fault-tolerant control for non-minimum phase hypersonic vehicles based on adaptive dynamic programming

Chinese Journal of Aeronautics 2024年第3期37卷 290-311页

作者： Le WANG Ruiyun QI Bin JIANG State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

In this paper,a novel adaptive Fault-Tolerant control(FTC)strategy is proposed for non-minimum phase Hypersonic Vehicles(HSVs)that are affected by actuator faults and parameter *** strategy is based on the output redefinition method and Adaptive Dynamic Programming(ADP).The intelligent FTC scheme consists of two main parts:a basic fault-tolerant and stable controller and an ADP-based supplementary *** the basic FTC part,an output redefinition approach is designed to make zero-dynamics stable with respect to the new ***,Ideal Internal Dynamic(IID)is obtained using an optimal bounded inversion approach,and a tracking controller is designed for the new output to realize output tracking of the nonminimum phase HSV *** the ADP-based compensation control part,an ActionDependent Heuristic Dynamic Programming(ADHDP)adopting an actor-critic learning structure is utilized to further optimize the tracking performance of the HSV control ***,simulation results are provided to verify the effectiveness and efficiency of the proposed FTC algorithm.

关键词： Hypersonic vehicle Fault-tolerant control Non-minimum phase system Adaptive control Nonlinear control Adaptive dynamic programming

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Insight into the Alkali Resistance Mechanism of CoMnHPMo Catalyst for NH_(3) Selective Catalytic Reduction of NO

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Transactions of Tianjin University 2024年第4期30卷 324-336页

作者： Kaixin Wang Yunchong Wang Zongxiang Yang Xinyue Wang Caixia Liu Qingling Liu Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityTianjin 300350China State Key Laboratory of Engines Tianjin UniversityTianjin 300350China

The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of ***,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation *** these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300􁕑.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal *** characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid *** situ DRIFTS was used to study the reaction pathways of the *** results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not ***,SCR performance was ensured even after alkali metal *** sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.

关键词： NH3-SCR Alkali resistance Phosphomolybdic acid CoMn

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Recent progress of diversiform humidity sensors based on versatile nanomaterials and their prospective applications

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Nano Research 2023年第10期16卷 11938-11958页

作者： Dongzhi Zhang Mengyu Wang Mingcong Tang Xiaoshuang Song Xixi Zhang Zhanjia Kang Xiaohua Liu Jianhua Zhang Qingzhong Xue State Key Laboratory of Heavy Oil Processing College of Control Science and EngineeringChina University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Heavy Oil Processing School of Materials Science and EngineeringChina University of Petroleum(East China)Qingdao 266580China

Humidity sensors are of significance in various fields,such as environmental and food quality monitoring,industrial processing,wearable and flexible electronics,and human health ***-performance humidity sensors with high sensitivity,rapid response time,and good stability are of paramount importance in humidity *** this paper,diversiform humidity sensors with different sensing mechanisms are summarized,including resistive,impedance,capacitive,quartz crystal microbalance(QCM),surface acoustic wave(SAW),field-effect transistor(FET),and optical fiber humidity *** nanomaterials such as graphene,transition-metal chalcogenide,MXenes,black phosphorus(BP),boron nitride(BN),polymers,and nanofibers were promising building-blocks for constructing humidity *** latest progress in the wearable and flexible humidity sensors,and self-powered humidity sensors was *** diversiform applications of the humidity sensors with great prospects were demonstrated in various fields in terms of human respiratory monitoring,skin dryness diagnosing,fingertip approaching,and non-contact ***,the challenges and prospects of nanomaterials-based humidity sensors were discussed.

关键词： humidity sensors nanomaterials wearable humidity sensors self-powered humidity sensors human respiratory monitoring

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Stability analysis of karst anti dip rock slope induced by underground coal mining——A case study of Jiguanling landslide, China

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Journal of Mountain Science 2025年第4期22卷 1226-1244页

作者： ZHONG Zuliang LIANG Erwei WANG Nanyun XU Yawei School of Civil Engineering Chongqing UniversityChongqing 400045China State key laboratory of coal mine disaster dynamics and control Chongqing 400044China Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education Chongqing 400045China

In recent years,the southwestern region of China has experienced a surge in significant mountain collapses,predominantly linked to underground mining *** investigation targets the Jiguanling area in Wulong,Chongqing,employing the UDEC numerical simulation technique to meticulously examine the deformation and failure characteristics,rock mass movement patterns,fracture evolution processes,and stress transmission mechanisms of anti-dip rock slopes composed of stratified *** slopes are inherently susceptible to bending and tilting due to their own *** findings elucidate that the predominant failure mode of anti-dip rock karst slopes is the inclined sliding(shear)type,which mirrors the fracture evolution mechanism as they extend in a quadrilateral pattern from the top and bottom plates of the mining area to the critical blocks at the rear and front edges of the *** disaster mechanism can be encapsulated as the"initial roof movement phase,direct roof collapse and crack propagation phase,critical block locking and sliding resistance phase,and deterioration phase".The four distinct stages of development and transformation encompass critical block slip(shear)and slope instability *** increase in coal seam thickness enlarges the deformation space in the lower part,while the dip angle of the coal seam influences the length and displacement range of rock fracture *** mining sequence alters the stress failure mode of the underlying critical blocks,and the vertical height of the mining step distance modifies the potential sliding surface and failure mode of the underlying critical ***,the distance between the goaf and the surface,along with the height of the mining impact,impacts the stability of the reverse *** results demonstrate that mining activities are the primary factor inducing the collapse of anti-dip rock slopes,with natural factors playing a secondary role.

关键词： Anti-dip rock slope Mining action Slope deformation mechanism Slope instability mechanism Evolution law of cracks

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Resilience-oriented Transmission Expansion Planning with Optimal Transmission Switching Under Typhoon Weather

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 129-138页

作者： Yang Yuan Heng Zhang Haozhong Cheng Zheng Wang Key Laboratory of Control of Power Transmission and Conversion Ministry of EducationElectrical Engineering DepartmentShanghai Jiao Tong UniversityShanghaiChina State Grid East China Branch ShanghaiChina

This paper presents resilience-oriented transmission expansion planning(RTEP)with optimal transmission switching(OTS)model under typhoon *** proposed model carefully considers the uncertainty of component vulnerability by constructing a typhoon-related box uncertainty set where component failure rate varies within a range closely related with typhoon ***,a min-max-min model is developed to enhance transmission network resilience,where the upper level minimizes transmission lines investment,the middle level searches for the probability distribution of failure status leading to max worst-case expected load-shedding(WCEL)under typhoon,and the lower level optimizes WCEL by economic dispatch(ED)and OTS.A nested decomposition algorithm based on benders decomposition is developed to solve the *** studies of modified IEEE 30-bus and 261-bus system of a Chinese region illustrate that:a)the proposed RTEP method can enhance resilience of transmission network with less investment than widely used RTEP method based on attacker and defender(DAD)model,b)the influence of OTS on RTEP is closely related with contingency severity and system scale and c)the RTEP model can be efficiently solved even in a large-scale system.

关键词： Decomposition algorithm optimal transmission switching resilience transmission expansion planning uncertainty vulnerability

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Assessment and Enhancement of FRC of Power Systems Considering Thermal Power Dynamic Conditions

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1371-1383页

作者： Feng Hong Yalei Pang Weiming Ji Lu Liang Fang Fang Junhong Hao Jizhen Liu State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources and School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China

Frequency stability and security have been a vital challenge as large-scale renewable energy is integrated into power *** contrast,the proportion of traditional thermal power units decreases during the decarbonization transformation process,resulting in poor frequency *** paper aims to explore the potential of frequency regulation support,dynamic assessment,and capacity promotion of thermal power plants in the transition *** the dynamic characteristics of the main steam working fluid under different working conditions,a nonlinear observer is constructed by extracting the main steam pressure and valve opening degree *** real-time frequency modulation capacity of thermal power units can provide a dynamic state for the power grid.A dynamic adaptive modification for primary frequency control(PFC)of power systems,including wind power and thermal power,is proposed and *** power dynamic allocation factor is adaptively optimized by predicting the speed droop ratio,and the frequency modulation capability of the system is improved by more than 11%under extreme ***,through the Monte Carlo simulation of unit states of the system under various working conditions,the promotion of the frequency regulation capacity with high wind power penetration(WPP)is verified.

关键词： Dynamic evaluation frequency regulation power system predictive modeling wind penetration

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A strategy for strengthening chaotic mixing of dual shaft eccentric mixers by changing non-Newtonian fluids kinetic energy distribution

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Chinese Journal of Chemical engineering 2024年第5期69卷 122-134页

作者： Songsong Wang Tong Meng Qian Zhang Changyuan Tao Yundong Wang Zequan Li Zuohua Liu School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing 400044China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Efficiently modulating the velocity distribution and flow pattern of non-Newtonian fluids is a critical challenge in the context of dual shaft eccentric mixers for process intensification,posing a significant barrier for the existing ***,this work reports a convenient strategy that changes the kinetic energy to controllably regulate the flow patterns from radial flow to axial *** showed that the desired velocity distribution and flow patterns could be effectively obtained by varying the number and structure of baffles to change kinetic energy,and a more uniform velocity distribution,which could not be reached normally in standard baffle dual shaft mixers,was easily ***,a comparative analysis of velocity and shear rate distributions is employed to elucidate the mechanism behind the generation of flow patterns in various dual-shaft eccentric ***,there is little difference in the power number of the laminar flow at the same Reynolds number,meaning that the baffle type has no effect on the power consumption,while the power number of both unbaffle and U-shaped baffle mixing systems decreases compared with the standard baffle mixing system in the transition ***,at the same rotational condition,the dimensionless mixing time of the U-shaped baffle mixing system is 15.3%and 7.9%shorter than that of the standard baffle and the unbaffle mixing system,respectively,which shows the advantage of the U-shaped baffle in stirring rate.

关键词： Dual shaft “U-shaped”baffle Flow pattern Mixing time Power demand

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Image-based quantitative probing of 3D heterogeneous pore structure in CBM reservoir and permeability estimation with pore network modeling

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International Journal of Coal Science & Technology 2024年第5期11卷 121-141页

作者： Peng Liu Yulong Zhao Zhengduo Zhao Huiming Yang Baisheng Nie Hengyi He Quangui Li Guangjie Bao State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China State Key Laboratory of Gas Disaster Detecting Preventing and Emergency ControllingChongqing 400037China College of Resources and Safety Engineering Chongqing UniversityChongqing 400030China China Coal Technology Engineering Group Chongqing Research Institute Chongqing 400037China

Coalbed methane(CBM)recovery is attracting global attention due to its huge reserve and low carbon burning benefits for the *** understanding the complex structure of coal and its transport properties is crucial for CBM *** study describes the implementation of mercury intrusion and μ-CT techniques for quantitative analysis of 3D pore structure in two anthracite *** shows that the porosity is 7.04%-8.47%and 10.88%-12.11%,and the pore connectivity is 0.5422-0.6852 and 0.7948-0.9186 for coal samples 1 and 2,*** fractal dimension and pore geometric tortuosity were calculated based on the data obtained from 3D pore *** results show that the pore structure of sample 2 is more complex and developed,with lower tortuosity,indicating the higher fluid deliverability of pore system in sample *** tortuosity in three-direction is significantly different,indicating that the pore structure of the studied coals has significant *** equivalent pore network model(PNM)was extracted,and the anisotropic permeability was estimated by PNM gas flow *** results show that the anisotropy of permeability is consistent with the slice surface porosity distribution in 3D pore *** permeability in the horizontal direction is much greater than that in the vertical direction,indicating that the dominant transportation channel is along the horizontal direction of the studied *** research results achieve the visualization of the 3D complex structure of coal and fully capture and quantify pore size,connectivity,curvature,permeability,and its anisotropic characteristics at micron-scale *** provides a prerequisite for the study of mass transfer behaviors and associated transport mechanisms in real pore structures.

关键词： CT image Heterogeneous pore structure Pore network model Coal permeability Coalbed methane

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An anonymous authentication and secure data transmission scheme for the Internet of Things based on blockchain

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Frontiers of Computer Science 2024年第3期18卷 183-197页

作者： Xingxing CHEN Qingfeng CHENG Weidong YANG Xiangyang LUO State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China Henan Key Laboratory of Grain Photoelectric Detection and Control Henan University of TechnologyZhengzhou 450001China Henan Province Key Laboratory of Cyberspace Situation Awareness Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China

With the widespread use of network infrastructures such as 5G and low-power wide-area networks,a large number of the Internet of Things(IoT)device nodes are connected to the network,generating massive amounts of ***,it is a great challenge to achieve anonymous authentication of IoT nodes and secure data *** present,blockchain technology is widely used in authentication and s data storage due to its decentralization and ***,Fan et *** a secure and efficient blockchain-based IoT authentication and data sharing *** studied it as one of the state-of-the-art protocols and found that this scheme does not consider the resistance to ephemeral secret compromise attacks and the anonymity of IoT *** overcome these security flaws,this paper proposes an enhanced authentication and data transmission scheme,which is verified by formal security proofs and informal security ***,Scyther is applied to prove the security of the proposed ***,it is demonstrated that the proposed scheme achieves better performance in terms of communication and computational cost compared to other related schemes.

关键词： Internet of Things blockchain authentication data transmission

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Wave nature of Rosensweig instability

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Chinese Physics B 2024年第3期33卷 471-479页

作者：李柳李德才戚志强王璐张志力 School of Mechanical Electronicand Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing 100044China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

The explicit analytical solution of Rosensweig instability spikes'shapes obtained by Navier-Stokes(NS)equation in diverse magnetic field H vertical to the flat free surface of ferrofluids are systematically studied experimentally and *** carefully analyzing and solving the NS equation in elliptic form,the force balanced surface equations of spikes in Rosensweig instability are expressed as cosine wave in perturbated magnetic field and hyperbolic tangent in large magnetic field,whose results both reveal the wave-like nature of Rosensweig *** results of hyperbolic tangent form are perfectly fitted to the experimental results in this paper,which indicates that the analytical solution is basically *** the forementioned theoretical results,the total energy of the spike distribution pattern is *** analyzing the energy components under different magnetic field intensities H,the hexagon-square transition of Rosensweig instability is systematically discussed and explained in an explicit way.

关键词： ferrofluids Rosensweig instability hexagon-square transition

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