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Identification of aircraft longitudinal aerodynamic parameters using an online corrective test for wind tunnel virtual flight

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Chinese Journal of Aeronautics 2024年第9期37卷 261-275页

作者： Shang TAI Chen BU Yanling wang ting YUE Hailiang LIU Lixin wang School of Aeronautical Science and Engineering Beihang UniversityBeijing 100191China AVIC Aerodynamics Research Institute Harbin 150001China

The identification of aerodynamic parameters is accomplished through the test data of the dynamic movement of scaled aircraft models flying dynamically in wind tunnel,which can real-ize the accurate acquisition of the aerodynamic model of the aircraft in the preliminary stage for aircraft design,and it is of great significance for improving the efficiency of aircraft ***-ever,the translational motion of the test model in the wind tunnel virtual flight is subject to con-straints that result in distinct flight dynamics compared to free *** constraints have implications for the accuracy of aerodynamic derivatives obtained through the identification of wind tunnel test *** this issue in mind,the research studies the differences in longitudinal dynamic characteristics between unconstrained free flight and wind tunnel virtual flight,and inno-vatively proposes an online correction test based wind tunnel virtual flight test *** lon-gitudinal trajectory and velocity changes of the model are solved online by the aerodynamic forces measured during the test,and then the coupled relationship between aircraft translation and rota-tion is used to correct the model's pitch attitude motion *** the first time,the problem of solving the data approximation for free flight has been solved,eliminating the difference between the dynamics of wind tunnel virtual flight and free flight,and improving the accuracy of the aero-dynamic derivative identification *** experiment's findings show that accurate aerodynamic derivatives can be identified based on the online correction test data,and the observed behaviour of the identified motion model has similarities to that of the free flight motion model.

关键词： Wind tunnels Displacement constraints Online solution Flightcontrol law Aerodynamic parameter identification

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Risk factors of non-arteritic anterior ischaemic optic neuropathy and central retinal artery occlusion

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 869-876页

作者： Chu-Han Ma Cong-Yao wang ting-ting Dai ting-ting Chen Wen-Hui Zhu Department of Ophthalmology the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina

AIM:To investigate the difference in risk factors between non-arteritic anterior ischaemic optic neuropathy(NAION)and central retinal artery occlusion(CRAO)and develop a predictive diagnostic ***:The study included 37 patients with monocular NAION,20 with monocular CRAO,and 24 with ***,age,and systemic diseases were *** routine,lipids,hemorheology,carotid and brachial artery doppler ultrasound,and echocardiography were *** optic disc area,cup area,and cup-to-disc ratio(C/D)of the unaffected eye in the NAION and CRAO group and the right eye in the hypertension group were ***:The carotid artery intimal medial thickness(C-IMT)of the affected side of the CRAO group was thicker(P=0.039)and its flow-mediated dilation(FMD)was lower(P=0.049)than the NAION *** with hypertension patients,NAION patients had higher whole blood reduced viscosity low-shear(WBRV-L)and erythrocyte aggregation index(EAI;P=0.045,0.037),and CRAO patients had higher index of rigidity of erythrocyte(IR)and erythrocyte deformation index(EDI;P=0.004,0.001).The optic cup and the C/D of the NAION group were smaller than the other two groups(P<0.0001).The diagnostic prediction model showed high diagnostic specificity(83.7%)and sensitivity(85.6%),which was highly related to hypertension,the C-IMT of the affected side,FMD,platelet(PLT),EAI,and C/***:CRAO patients show thicker C-IMT and worse endothelial function than *** and CRAO may be related to abnormal hemorheology.A small cup and small C/D may be involved in *** diagnostic nomogram can be used to preliminarily identify NAION and CRAO.

关键词： non-arteritic anterior ischaemic optic neuropathy central retinal artery occlusion risk factors diagnostic prediction model nomogram

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A nonlocal dispersal and time delayed HIV infection model with general incidences

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 448-457页

作者： WU Peng ZHANG Yu-huai wang ling School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China School of Humanities and Management Zhejiang Chinese Medical UniversityHangzhou 311402China Public Foundational Courses Department Nanjing Vocational University of Industry TechnologyNanjing 210023China

Biologically,because of the impact of reproduction period and nonlocal dispersal of HIV-infected cells,time delay and spatial heterogeneity should be *** this paper,we establish an HIV infection model with nonlocal dispersal and infection ***,applying the theory of Fourier transformation and von Foerster rule,we transform the model to an integrodifferential equation with nonlocal time delay and *** well-posedness,positivity,and boundedness of the solution for the model are studied.

关键词： HIV model nonlocal dispersal time delay general incidences

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Impact pressure of waves generated by landslides on bank slopes

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Journal of Mountain Science 2024年第3期21卷 918-931页

作者： CAO ting wang Pingyi QIU Zhenfeng LIU Jie Key Laboratory of Hydraulic and Waterway Engineering of Ministry of Education Chongqing Jiaotong UniversityChongqing 400074China Engineering Research Center of Diagnosis Technology and Instruments of Hydro-Construction Chongqing Jiaotong UniversityChongqing 400074China

Impulse waves that are generated by landslides in narrow reservoir areas threaten the stability of buildings and bank *** discuss the action process and evolution law of the wave pressure on bank slopes,a three-dimensional physical model test that considers impulse waves generated by landslides was performed,and factors including landslide width,thickness,slope angles of the sliding surface,and bank slope angle were *** on wave forms on the bank slopes,wave pressure curve characteristics,and peak value,the action process of wave pressure could be divided into the following stages:maximum pulsating pressure stage,wave impact stage(when waves break),and stationary pulsation *** was found that wave breaking is dependent on the value of the surf similarity parameterξ.The distribution pattern of impact pressure decays linearly on both sides of the maximum impact pressure point,and the attenuation degree decreases when it attains 40%of the maximum ***,it is proposed that the prediction formula for the maximum effective impact pressure of the bank slope be related to the reciprocal of wave steepness,relative water depth,and slope *** prediction formula provides strong theoretical support for early safety warning and for predicting the bank slope under impulse waves generated by landslides.

关键词： Model test Impact pressure Action stage Breaking discrimination Distribution model

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Causal Analysis Between Rice Growth and Cadmium Accumulation and Transfer under Arbuscular Mycorrhizal Inoculation

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Rice science 2024年第2期31卷 226-236页

作者： ZHAO ting wang Li YANG Jixian MA Fang State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Cadmium(Cd)contamination in rice has been a serious threat to human *** investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was *** results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF *** led to an increase in the net photosynthetic rate and antioxidant enzyme activity of *** the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control ***,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the *** coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in *** translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal *** study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.

关键词： cadmium transfer dilution effect heavy metal immobilization mycorrhizal effect path analysis phenotypic plasticity

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Online Pareto optimal control of mean-field stochastic multi-player systems using policy iteration

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Science China(Information Sciences) 2024年第4期67卷 21-37页

作者： Xiushan JIANG Yanshuang wang Dongya ZHAO ling SHI College of New Energy China University of Petroleum(East China) Department of Electronic and Computer Engineering Hong Kong University of Science and Technology

In this study, the Pareto optimal strategy problem was investigated for multi-player mean-field stochastic systems governed by It? differential equations using the reinforcement learning(RL) method.A partially model-free solution for Pareto-optimal control was derived. First, by applying the convexity of cost functions, the Pareto optimal control problem was solved using a weighted-sum optimal control problem. Subsequently, using on-policy RL, we present a novel policy iteration(PI) algorithm based on the Hrepresentation technique. In particular, by alternating between the policy evaluation and policy update steps,the Pareto optimal control policy is obtained when no further improvement occurs in system performance,which eliminates directly solving complicated cross-coupled generalized algebraic Riccati equations(GAREs).Practical numerical examples are presented to demonstrate the effectiveness of the proposed algorithm.

关键词： mean-field stochastic systems Pareto optimal control policy iteration scheme $\mathcal{H}$-representation

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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1342-1357页

作者： Sheng Qi Rui wang Tao Zhang Xu Yang Ruiqing Sun ling wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China Xiangjiang Laboratory Changsha 410205China College of Computer National University of Defense TechnologyChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China IEEE

Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are *** a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec ***,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables ***,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is *** data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between *** by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these *** mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast ***-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed.

关键词： Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.

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High-temperature stability of retained austenite and plastic deformation mechanism of ultra-fine bainitic steel isothermally treated below Ms

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Journal of Iron and Steel Research International 2024年第8期31卷 2014-2030页

作者： ting-ting He Feng Hu Kun wang Wen Zhou Li Li Serhii Yershov Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan 430081HubeiChina Zhejiang Tsingshan Iron and Steel Co. Ltd.Qingtian 323903ZhejiangChina

The mechanical properties of the sample and the stability of retained austenite were studied by designing two kinds of ultra-fine bainitic steel with different heat treatment methods austempering above and below Ms(martensite start tem-perature),which were subjected to tensile tests at 20 and 450℃,*** results show that compared to room temperature(20℃)tensile properties,the uniform elongation of the sample at high temperature(450℃)significantly ***,the uniform elongation of the sample austempered above Ms decreased from 8.0%to 3.5%,and the sample austempered below Ms decreased from 10.9%to 3.1%.Additionally,the tensile strength of the sample austempered above Ms significantly decreased(from 1281 to 912 MPa),and the sample austempered below Ms slightly decreased(from 1010 to 974 MPa).This was due to the high carbon content(1.60 wt.%),high mechanical stability,low thermal stability for the retained austenite of the sample austempered below ***,the retained austenite decomposed at high temper-atures,the carbon content and transformation driving force were significantly reduced,the transformation rate increased,and the phase transformation content reduced.

关键词： Ultra-fine bainite Isothermal treatment High-temperature tensile property Retained austenite stability Plastic deformation

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Enhancing Evolutionary Algorithms With Pattern Mining for Sparse Large-Scale Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1786-1801页

作者： Sheng Qi Rui wang Tao Zhang Weixiong Huang Fan Yu ling wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China College of Systems Engineering National University of Defense TechnologyChangsha 410073and also with the Xiangjiang LaboratoryChangsha 410205China College of Transportation and Engineering Central South UniversityChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China

Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and ***,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to traverse vast expanse with limited computational ***,in the context of sparse,most variables in Pareto optimal solutions are zero,making it difficult for algorithms to identify non-zero variables *** paper is dedicated to addressing the challenges posed by *** start,we introduce innovative objective functions customized to mine maximum and minimum candidate *** substantial enhancement dramatically improves the efficacy of frequent pattern *** this way,selecting candidate sets is no longer based on the quantity of nonzero variables they contain but on a higher proportion of nonzero variables within specific ***,we unveil a novel approach to association rule mining,which delves into the intricate relationships between non-zero *** novel methodology aids in identifying sparse distributions that can potentially expedite reductions in the objective function *** extensively tested our algorithm across eight benchmark problems and four real-world *** results demonstrate that our approach achieves competitive solutions across various challenges.

关键词： Evolutionary algorithms pattern mining sparse large-scale multi-objective problems(SLMOPs) sparse large-scale optimization.

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Unlocking stability:Preserving activity of biomimetic catalysts with covalent organic framework cladding

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Chinese Chemical Letters 2024年第6期35卷 1-2页

作者： ting wang Xin Yu Yaqiang Xie College of the Environment&Ecology Xiamen UniversityXiamen 361102China

Enzymes are extremely complicated biocatalysts in several industrial processes due to their numerous advantages over conventional catalysts,including lower physiological and environmental toxicity,exceptional selectivity,and milder reaction conditions[1].However,their widespread applications are constrained by the high production costs,low operational stability,and complexity involved in the recovery and reusability of enzymes[2].

关键词： stability catalysts exceptional

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