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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun zhu Fu-San Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 1.^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Adaptive nonlinear Kalman filters based on credibility theory with noise correlation

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Chinese Journal of Aeronautics 2024年第6期37卷 232-243页

作者： Quanbo GE Zihao SONG Bingtao zhu Bingjun ZHANG School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing 210044China School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 330013China School of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China School of Electronic and Information Engineering Tongji UniversityShanghai 200092China

To solve the divergence problem and overcome the difficulty in guaranteeing filtering accuracy during estimation of the process noise covariance or the measurement noise covariance with traditional new information-based nonlinear filtering methods,we design a new method for estimating noise statistical characteristics of nonlinear systems based on the credibility Kalman Filter(KF)theory considering noise *** method first extends credibility to the Unscented Kalman Filter(UKF)and Extended Kalman Filter(EKF)based on the credibility ***,an optimization model for nonlinear credibility under noise related conditions is established considering noise correlation.A combination of filtering smoothing and credibility iteration formula is used to improve the real-time performance of the nonlinear adaptive credibility KF algorithm,further expanding its application scenarios,and the derivation process of the formula theory is ***,the performance of the nonlinear credibility filtering algorithm is simulated and analyzed from multiple perspectives,and a comparative analysis conducted on specific experimental *** simulation and experimental results show that the proposed credibility EKF and credibility UKF algorithms can estimate the noise covariance more accurately and effectively with lower average estimation time than traditional methods,indicating that the proposed algorithm has stable estimation performance and good real-time performance.

关键词： Kalman filter Extended Kalman Filter(EKF) Unscented Kalman Filter(UKF) Credibility Noise correlation

Semi-tensor product approach for partially symmetric games

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Journal of Control and Decision 2024年第1期11卷 98-106页

作者： Lei Wang Jiandong zhu School of Mathematical Sciences Nanjing Normal UniversityNanjingPeople’s Republic of China

In this paper,a criterion for the partially symmetric game(PSG)is derived by using the semitensor product *** dimension and the basis of the linear subspace composed of all the PSGs with respect to a given set of partial players are *** testing equations with the minimum number are concretely determined,and the computational complexity is ***,two examples are displayed to show the theoretical results.

关键词： Partially symmetric game semi-tensor product of matrices adjacent transpositions

Photodegradation of xylene isomers:Kinetics,mechanism,secondary pollutant formation potential and health risk evaluation

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Journal of Environmental Sciences 2024年第2期136卷 658-669页

作者： Xiaoyan Chen Weikun zhu Sufen Feng Jiangyao Chen Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Photodegradation technology has been widely applied in the purification of industrial aromatic ***,whether this technology efficiently removes the pollutants to prevent secondary pollution and health risk is still ***,the photodegradation processes of three xylenes were compared under designed reaction atmospheres and light *** lamp showed poor photodegradation ability toward xylenes,no matter in N_(2) or N_(2)+O_(2)system,while much higher photodegradation performance of xylenes were obtained under ultraviolet(UV)and vacuum ultraviolet(VUV)irradiation,especially in N_(2)+O_(2)+VUV system,where 97.9%of m-xylene,99.0%of o-xylene or 87.5%of p-xylene with the initial concentration of 860 mg/m^(3) was removed within 240 *** xylenes underwent three processes of photo-isomerization,photodecomposition and photo-oxidation to produce intermediates of aromatics,alkanes and *** them,the photo-isomerization products showed the highest concentration percentage(e.g.,≥50%in o-xylene system),confirming that photo-isomerization reaction was the dominated photodegradation process of ***,these isomerized products not only contributed about 97%and91.to the formation potential of O3(OFP)and secondary organic aerosols(SOAFP),but also displayed obvious non-carcinogenic risk,although one of photodecomposition product—benzene showed the highest occupational exposure ***,the secondary pollution and health risks of photodegradation products of xylenes were non-ignorable,although the OFP,SOAFP and health risks of the generated products reduced at least 4.5 times in comparison with that of the degraded *** findings are helpful for the appropriate application of this technology in the purification of industrial organic waste gas.

关键词： Isomer aromatics Photodegradation Ozone formation Secondary organic aerosols Health risk

Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： Liangyu zhu Xian Li Bujin Feng Fan Liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.1.% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic Energy Estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng Yuan Yuzhong Zhang Shiqiang Liu Rong zhu State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.1.%to 1..71.)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

High-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu Feng zhu Yue Wang Donghang Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHM)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHM-TADFNA-D WOLED exhibit a remarkable EQE of 1..8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Ground threat prediction-based path planning of unmanned autonomous helicopter using hybrid enhanced artificial bee colony algorithm

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Defence Technology（防务技术） 2024年第2期32卷 1-22页

作者： Zengliang Han Mou Chen Haojie zhu Qingxian Wu School of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning *** to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking ***,a dynamic threat distribution probability model is developed based on the characteristics of typical ground *** dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real ***,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground *** adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly ***,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking *** proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and ***,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method.

关键词： UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking

Fabrication of porous adsorbents from eco-friendly aqueous foam for high-efficient removal of cationic dyes and sustainable utilization assessment

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Journal of Environmental Sciences 2024年第3期137卷 395-406页

作者： Fangzhi Duan Yongfeng zhu Yan Liu Aiqin Wang Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-material and Green ChemistryLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Porous materials applied in environmental remediation have received researchers'extensive attention recently,but the related green and convenient preparation method is rarely ***,we recommended a green and convenient strategy for the fabrication of porous material via aqueous foam templates,which was synergistically stabilized by Codonopsis pilosula(CP)and clay minerals of attapulgite(APT).The characterization results revealed that the APT was modified by organic molecules leached from CP and anchored at the air-water interface,which improved the foam stability *** novel porous material of polyacrylamide/Codonopsis pilosula/attapulgite(PAM/CP/APT)templated from the aqueous foam via a polymerization reaction had excellent adsorption capacity for the cationic dyes methyl violet(MV)and methylene blue(MB),and the adsorption capacity can reach 755.85 mg/g and557.64 mg/g,*** importantly,the adsorption capacity of spent adsorbent material was still over 200 mg/g after being recycled five times through a simple carbonization process,and then it was added to the plant pot,the total biomass was increased by about86.42%.This study provided a green and sustainable pathway for the preparation,application and subsequent processing of porous materials.

关键词： Porous material Aqueous foam Atapulgite Adsorption Cationic dyes Sustainable utilization

An Uncertainty Evaluation on the ΔK_(th) and ΔK_(IC) of Fine-grained Isotropic Graphite

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Acta Mechanica Solida Sinica 2024年第3期37卷 478-486页

作者： Yantian Zhang Lina zhu Ruiguo Yan Xishu Wang Department of Engineering Mechanics Tsinghua UniversityBeijing100084China Wheel-Rail Center Tianjin Research Institute for Advanced EquipmentTsinghua UniversityTianjin300300China

This paper intensively explores the critical issues related to the quantitative and accurate evaluations of FCG behavior in the early stage,macro fatigue fracture toughness,and the critical crack size for damage tolerance in nuclear *** address these issues,scale-span FCG tests were carried out using two typical specimens,CT and SEM in-situ *** results indicate that the FCG threshold and the effective FCG length have a significant correlation with the modified maximum loop stress theory for a mixed I/II *** particular,the effective FCG length(a_(eq))and the applied stress threshold of polycrystalline graphite are important parameters for fatigue damage tolerance design in engineering *** influencing factors of ΔK_(th,eq) and a_(eq) were discussed in detail using the mixed I/II mode,*** addition,the scattered values of ΔK_(IC) for this graphite can be quantitatively estimated using the Weibull distribution *** predicated parameters and experimental results demonstrate a strong correlation.

关键词： Nuclear graphite Mixed I/II mode Fatigue crack Fatigue crack growth threshold Fatigue fracture toughness