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Optimal crater landmark selection based on optical navigation performance factors for planetary landing

Chinese Journal of Aeronautics 2023年第3期36卷 254-270页

作者： Yi XIU Shengying ZHU Rui XU Maodeng LI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100091China

Planetary craters are natural navigation landmarks that widely exist and are easily *** navigation based on crater landmarks has become an important autonomous navigation method for planetary *** to the increase in observed crater landmarks and the limitation of onboard computation,the selection of good crater landmarks has gradually become a research hotspot in the field of landmark-based optical *** paper designs a fast crater landmark selection method,which not only considers the configuration observability of crater subsets but also focuses on the influence on navigation performance arising from the measurement uncertainty and the matching confidence of craters,which is different from other landmark selection *** factor of measurement uncertainty,which is anisotropic,correlated and nonidentically distributed,is quantified and integrated into selection based on crater pairing detection and localization error *** addition,the concept of the crater matching confidence factor is introduced,which reflects the possibility of 2D projection measurements corresponding to 3D *** with the configuration observability factor,the crater landmark selection indicator is ***,the effectiveness of the proposed method is verified by Monte Carlo simulations.

关键词： Crater-based optical navigation Crater landmark selection Crater matching Measurement uncertainty Planetary landing

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Comparative Analysis of Noise Margin Between Pure SET-SET and Hybrid SET-PMOS Inverters

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Chinese Journal of Electronics 2025年第1期34卷 146-155页

作者： Fan Zhang Yi Liu Yibo Wang Minghu Wu Sheng Hu Youli Dong Hubei Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of Technology School of Electrical and Electronic Engineering Hubei University of Technology

Single-electron transistor（SET） is considered as one of the promising candidates for future electronic devices due to its advantages of low power consumption and high integration. The comparative analysis of SET-based inverters, especially the noise margin, is carried out. Pure SET-SET and hybrid SET with p type metal oxide semiconductor（SET-PMOS） inverters are designed for investigation. The effects of SET supply voltage, junction resistance and junction capacitance on noise tolerance and power consumption of inverters are studied. For hybrid SET-PMOS inverters, the noise margin for a logic high（NMH） is less than 60 mV under various conditions, which may become the bottleneck of its application. For pure SET-SET inverters, both NMH and the noise margin for a logic low（NML） could reach 300 mV at a supply voltage of 0.8 V. The minimum power consumption of pure SET-SET and hybrid SET-PMOS inverters is 2.85 nW and 58 nW, respectively. The pure SET-SET inverters have greater noise tolerance and lower power consumption, which is more conducive to large-scale integration. When junction capacitance CJ= 0.0273 aF and junction resistance RT≥1 MΩ in SET-SET inverters at a supply voltage of 0.8 V, the NMH and NML are not significantly affected by the junction resistance and the noise margin fluctuates at 300 mV.

关键词： Resistance Power demand Noise Metals Capacitance Inverters Large scale integration Logic Junctions Single electron transistors

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Interaction and characteristics of furfural residues and polyvinyl chloride in fast co-pyrolysis

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Frontiers of Chemical Science and engineering 2024年第12期18卷 13-21页

作者： Yue Zhang Moshan Li Erfeng Hu Rui Qu Shuai Li Qingang Xiong State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

This study investigated the interaction between the furfural residue and polyvinyl chloride co-pyrolysis using an infrared heating *** analytical techniques including production distribution analysis,thermal behavior,pyrolysis kinetic,simulated distillation and gas chromatography-mass spectrography(GCMS),and X-ray photoelectron spectroscopy were utilized to elucidate the pyrolysis characterization and reaction mechanism during the ***,the yield of co-pyrolysis oil increased from 35.12%at 5℃·s^(–1)to 37.70%at 10℃·s^(-1),but then decreased to 32.07%at 20℃·s^(-1).Kinetic and thermodynamic parameters suggested non-spontaneous and endothermic *** analysis revealed that aromatic hydrocarbons,especially mono-and bi-cyclic ones,are the predominant compounds in the oil due to the presence of H radicals in polyvinyl chloride,suggesting an enhancement in oil ***,the fixed chlorine content increased to 65.11%after co-pyrolysis due to the interaction between inorganic salts in furfural residues and chlorine from polyvinyl chloride.

关键词： infrared heating pyrolysis oil polyvinyl chloride chlorine co-pyrolysis

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Bamboo-like MnO_(2)·Co_(3)O_(4):High-performance catalysts for the oxidative removal of toluene

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Journal of Environmental Sciences 2025年第1期147卷 617-629页

作者： Ali Rastegarpanah Jiguang Deng Yuxi Liu Lin Jing Wenbo Pei Jia Wang Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

Themanganese-cobalt mixed oxide nanorodswere fabricated using a hydrothermalmethod with different metal precursors(KMnO_(4)and MnSO_(4)·H_(2)O for MnOx and Co(NO3)2>6H_(2)O and CoCl_(2)>6H_(2)O for Co_(3)O_(4)).Bamboo-like MnO_(2)>Co_(3)O_(4)(B-MnO_(2)>Co_(3)O_(4)(S))was derived from repeated hydrothermal treatments with Co_(3)O_(4)@MnO_(2)and MnSO_(4)>H_(2)O,whereas Co_(3)O_(4)@MnO_(2)nanorods were derived from hydrothermal treatment with Co_(3)O_(4)nanorods and KMnO_(4).The study shows that manganese oxide was tetragonal,while the cobalt oxide was found to be cubic in the crystalline *** surface ions were present in multiple oxidation states(e.g.,Mn^(4+)and Mn^(3+))and surface oxygen *** content of adsorbed oxygen species and reducibility at low temperature declined in the sequence of BMnO_(2)>Co_(3)O_(4)(S)>Co_(3)O_(4)@MnO_(2)>MnO_(2)>Co_(3)O_(4),matching the changing trend in *** all the samples,B-MnO_(2)>Co_(3)O_(4)(S)showed the preeminent catalytic performance for the oxidation of toluene(T10%=187℃,T50%=276℃,and T90%=339℃).In addition,the B-MnO_(2)>Co_(3)O_(4)(S)sample also exhibited good H_(2)O^(-),CO_(2)^(-),and SO_(2)^(-)resistant *** good catalytic performance of B-MnO_(2)>Co_(3)O_(4)(S)is due to the high concentration of adsorbed oxygen species and good reducibility at low *** oxidation over B-MnO_(2)>Co_(3)O_(4)(S)proceeds through the adsorption of O_(2)and toluene to form O∗,OH∗,and H_(2)C(C6H5)∗species,which then react to produce benzyl alcohol,benzoic acid,and benzaldehyde,ultimately converting to CO_(2)and H_(2)*** findings suggest that B-MnO_(2)>Co_(3)O_(4)(S)has promising potential for use as an effective catalyst in practical applications.

关键词： Manganese-cobalt mixed oxide Nanorod Bamboo-like morphology Hydrothermal method Toluene oxidation

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Numerical investigation on dynamic response of the screen mesh in vibrating screening through DEM-FEM co-simulation

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Particuology 2024年第4期87卷 205-217页

作者： Huan Zhang Xiao Zheng Weimin Jing Key Laboratory of MetallurgicalEquipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081 China Hubei Key Laboratory of Mechanical Transmssion and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044China

Dynamic response of the screen mesh is of great significance in the optimum vibrating screen *** this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle ***,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen ***,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the ***,the influence of screening parameters on LVA and its distribution was *** results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.

关键词： Vibrating screen Dynamic response DEM-FEM Screening parameters Local vibration amplitude

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Cooperative decision-making algorithm with efficient convergence for UCAV formation in beyond-visual-range air combat based on multi-agent reinforcement learning

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Chinese Journal of Aeronautics 2024年第8期37卷 311-328页

作者： Yaoming ZHOU Fan YANG Chaoyue ZHANG Shida LI Yongchao WANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang UniversityHangzhou 310027China

Highly intelligent Unmanned Combat Aerial Vehicle(UCAV)formation is expected to bring out strengths in Beyond-Visual-Range(BVR)air *** Multi-Agent Reinforcement Learning(MARL)shows outstanding performance in cooperative decision-making,it is challenging for existing MARL algorithms to quickly converge to an optimal strategy for UCAV formation in BVR air combat where confrontation is complicated and reward is extremely sparse and *** to solve this problem,this paper proposes an Advantage Highlight Multi-Agent Proximal Policy Optimization(AHMAPPO)***,at every step,the AHMAPPO records the degree to which the best formation exceeds the average of formations in parallel environments and carries out additional advantage sampling according to ***,the sampling result is introduced into the updating process of the actor network to improve its optimization ***,the simulation results reveal that compared with some state-of-the-art MARL algorithms,the AHMAPPO can obtain a more excellent strategy utilizing fewer sample episodes in the UCAV formation BVR air combat simulation environment built in this paper,which can reflect the critical features of BVR air *** AHMAPPO can significantly increase the convergence efficiency of the strategy for UCAV formation in BVR air combat,with a maximum increase of 81.5%relative to other algorithms.

关键词： Unmanned combat aerial vehicle(UCAV)formation Decision-making Beyond-visual-range(BVR)air combat Advantage highlight Multi-agent reinforcement learning(MARL)

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Seismic fragility analysis of three-tower cable-stayed bridges with different connection configurations

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Earthquake engineering and engineering Vibration 2024年第4期23卷 1009-1027页

作者： Chen Chen Liu Jinlong Lin Junqi Li Suchao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China Key Laboratory of Structural Dynamic Behavior and Control Ministry of EducationHarbin Institute of TechnologyHarbin 150090China

Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study the effects of connection configurations on seismic responses and *** element models of bridges are established using OpenSees.A new ground motion screening method based on the statistical characteristic of the predominant period is proposed to avoid irregular behavior in the selection process of ground motions,and incremental dynamic analysis(IDA)is performed to develop components and systems fragility *** effects of damper failure on calculated results for PEDS are examined in terms of seismic response and fragility *** results show that the bridge tower is the most affected component by different structural *** RS,the fragility of the middle tower is significantly higher than other components,and the bridge failure starts from the middle tower,exhibiting a characteristic of local *** FS and PEDS,the fragility of the edge tower is higher than the middle *** system fragility of RS is higher than FS and *** the failure of dampers into account is necessary to obtain reliable seismic capacity of cable-stayed bridges.

关键词： seismic fragility cable-stayed bridge connection configuration viscous damper comparison analysis

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CeO_(2)@MnO_(2)with strong Ce-Mn interaction activating PDS to promote in situ degradation of adsorbed tetracycline

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Journal of Rare Earths 2025年第3期43卷 490-499,I0003页

作者： Jinhui Zhang Jiawei Sun Xinfeng Zhu Jingquan Liu Linlin Chang Guofeng Li Rongfu Peng Junning Wang Libin Jiang Kai Wang Shiqiang Yin Xueping Liu Chaohai Wang Henan Key Laboratory of Water Pollution Control and Rehabilitation Technology School of Municipal and Environmental EngineeringHenan University of Urban ConstructionPingdingshan467036China National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangzhou510006China School of Light Industry&Chemical Engineering Dalian Polytechnic UniversityDalian116034China

A series of CeO_(2)@MnO_(2)composites was prepared by deposition-precipitation *** materials were used to activate sodium persulfate(PDS)for the oxidation of *** is found that the composites,especially the CeO_(2)@MnO_(2)-1:4 composites,exhibit better tetracycline removal rates than the pure components.X-ray diffraction(XRD),Raman and scanning electron microscopy(SEM)analyses all indicate that the composite has been successfully prepared with high purity and high *** XPS analysis shows that the strong interaction between the components promotes the electron ***,the kinetic rate constants of CeO_(2)@MnO_(2)-1:4 after 60 min are 3.8 and 12.7 times higher than pure CeO_(2)and MnO_(2),***_(2)@MnO_(2-)1:4 composite also exhibits excellent catalytic activity for individual and hybrid *** effects of wastewater matrix,pH,circulation and ion stre ngth on the degradation of tetracycline were *** is found that CeO_(2)@MnO_(2)-1:4 composite has good practical application ***_(2)@MnO_(2)composites with synergistic adsorption catalysis can activate PDS and peroxymo no sulfate(PMS)for efficient organic catalytic *** paper provides the theoretical basis and data support for the practical application of the CeO_(2)@MnO_(2)composite materials.

关键词： Tetracycline Multicomponent contamination Adsorption-catalytic synergy Anti-interference CeO_(2)@MnO_(2) Rare earths

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Mechanisms of isomerization and hydration reactions of typicalβ-diketone at the air-droplet interface

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Journal of Environmental Sciences 2024年第7期141卷 225-234页

作者： Yuemeng Ji Weiyong Luo Qiuju Shi Xiaohui Ma Ziqi Wu Weina Zhang Yanpeng Gao Taicheng An Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlInstitute Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of EducationSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Acetylacetone(AcAc)is a typical class ofβ-diketones with broad industrial applications due to the property of the keto-enol isomers,but its isomerization and chemical reactions at the air-droplet interface are still ***,using combined molecular dynamics and quantum chemistry methods,the heterogeneous chemistry of AcAc at the air-droplet interface was investigated,including the attraction of AcAc isomers by the droplets,the distribution of isomers at the air-droplet interface,and the hydration reactions of isomers at the air-droplet *** results reveal that the preferential orientation of two AcAc isomers(keto-and enol-AcAc)to accumulate and accommodate at the acidic air-droplet *** isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the“water bridge”structure is destroyed by H_(3)O^(+),especially for the isomerization from keto-Ac Ac to *** the acidic air-droplet interface,the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to ***-diol is the dominant products to accumulate at the air-droplet interface,and excessive keto-diol can enter the droplet interior to engage in the *** photooxidation reaction of AcAc will increase the acidity of the air-droplet interface,which indirectly facilitate the uptake and formation of more *** results provide an insight into the heterogeneous chemistry ofβ-diketones and their influence on the environment.

关键词： Acetylacetone Air-droplet interface Theoretical simulation Isomerization Hydration reaction mechanism

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Modeling differential car-following behavior under normal and rainy conditions: A memory-based deep learning method with attention mechanism

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Chinese Physics B 2023年第6期32卷 187-202页

作者：柏海舰过晨晨丁恒卫立阳孙婷陈星宇 School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of Cognitive Intelligence Hefei 230009China

In order to analyze and learn the difference in car-following behavior between normal and rainy days, we first collect car-following trajectory data of an urban elevated road on normal and rainy days by microwave radar and analyze the differences in speed, relative speed, acceleration, space headway, and time headway among data through statistics. Secondly, owing to the time-series characteristics of car-following data, we use the long short-term memory(LSTM) neural network optimized by attention mechanism(AM) and sparrow search algorithm(SSA) to learn the different car-following behaviors under different weather conditions and build corresponding models(ASL-Normal, ASL-Rain, where ASL stands for AM-SSA-LSTM), respectively. Finally, the simulation test shows that the mean square error(MSE) and reciprocal of time-to-collision(RTTC) of the ASL model are better than those of LSTM and intelligent diver model(IDM), which is closer to the real data. The ASL model can better learn different driving behaviors on normal and rainy days. However,it has a higher sensitivity to weather conditions from cross test on normal and rainy data-sets which need classification training or sample diversification processing. In the car-following platoon simulation, the stability performances of two models are excellent, which can describe the basic characteristics of traffic flow on normal and rainy days. Comparing with ASL-Rain model, the convergence time of ASL-Normal is shorter, reflecting that cautious driving behavior on rainy days will reduce traffic efficiency to a certain extent. However, ASL-Normal model produces a more severe and frequent traffic oscillation within a shorter period because of aggressive driving behavior on normal days.

关键词： car-following behavior deep learning weather condition heterogeneous traffic flow

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