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China Geology 2023年第4期6卷 756-758页

作者： Jin-qiu li Yong-shuang Zhang Xue li San-shao Ren li-na ran China University of Geosciences Beijing 100083China Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

1. Objectives Ophiolites from the oceanic crust are important indicators for identifying tectonic suture zones. Recently, a continuous ophiolite belt was found near the Guola Mountain in the Nujiang tectonic belt. Due to intensive hydrothermal alteration during tectonic evolution, clayey altered ophiolite with special engineering geological characteristics was formed, which has an extremely adverse impact on engineering stability. However, the adverse properties of clayey altered ophiolite are still not well understood in engineering practices(Zhang YS, et al., 2011).

关键词： tectonic belt ophiolite

Understanding the factors influencing cloud-core vertical accelerations during deep convection formation in the WRF model

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 1-7页

作者： na li Jin Wang lingkun ran Lei Yin Xiba Tang Yuchen liu Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Guizhou Meteorological Bureau GuiyangChina University of Chinese Academy of Sciences BeijingChina nanjing University of Posts and Telecommunications NanjingChina Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunmingChina

本文将扰动气压利用一个线性诊断关系代替,重新推导了WRF模式框架地形追随坐标系下的垂直动量方程,建立了垂直加速与对流触发(DCI)影响因子(如温度,水汽等)的直接联系.研究发现,DCI过程与对流核垂直加速相关,三维副散,扰动位势在垂直方... 详细信息

本文将扰动气压利用一个线性诊断关系代替,重新推导了WRF模式框架地形追随坐标系下的垂直动量方程,建立了垂直加速与对流触发(DCI)影响因子(如温度,水汽等)的直接联系.研究发现,DCI过程与对流核垂直加速相关,三维副散,扰动位势在垂直方向的二阶非均匀性,扰动位温垂直梯度,比湿及其垂直梯度,水凝物拖曳,均是能够直接影响垂直加速和对流触发的物理因子,这些量与模式基本预报量相关,通过解析基本预报量对对流发展的直接影响,可能有助于理解模式对DCI过程预测失败的原因.

关键词：垂直加速深对流垂直速度冰雹

Neighboring optimal guidance using higher-order dynamics approximation with application to orbital injection problem

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Chinese Journal of Aeronautics 2024年第5期37卷 426-440页

作者： Xinglun CHEN ran ZHANG Huifeng li School of Astronautics Beihang UniversityBeijing 100191China

Neighboring optimal guidance,a method to obtain a suboptimal guidance law by approximately solving the first-order necessary conditions based on a nominal trajectory,is widely used in the aerospace field due to its high computational efficiency and low resource *** more advanced scenarios,the existing methods still have a problem that the guidance accuracy and optimality will seriously degrade when the actual state largely deviates from the nominal *** is mainly caused by the approximate description of the first-order conditions in terms of total flight time and nonlinear *** address this problem,a higher-order neighboring optimal guidance method is ***,a novel total flight time updating strategy,together with a normalized time scale,is presented that transforms the optimal problem with free total flight time into a more tractable optimal problem with fixed total flight ***,using the vector partial derivative method,a higher-order approximation is adopted,instead of the first-order approximation,to accurately describe the nonlinear dynamical and terminal constraints,thus obtaining a polynomially constrained quadratic optimal ***,to numerically solve the polynomially constrained quadratic optimal problem,a Newton-type iterative algorithm based on the orthogonal decomposition is *** the iterative solution within each guidance period,the corrections to control quantities and total flight time are *** proposed method is applied to a launch vehicle orbital injection problem,and simulation results show that it achieves high accuracy of orbital injection and optimality of performance index.

关键词： Optimal control Neighboring optimal guidance Launch vehicles Orbital injection Higher-order approximation

Prescribed-time stabilization and inverse optimal control of stochastic high-order nonlinear systems

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Science China(Information Sciences) 2024年第2期67卷 144-156页

作者： ran liU Hui WANG Wuquan li School of Mathematics and Statistics Science Ludong University

This paper investigates the prescribed-time state-feedback stabilization and prescribed-time inverse optimality problems for stochastic high-order nonlinear systems. First, a time-varying controller is designed by developing scaled quartic Lyapunov functions, which can guarantee that the system has a unique strong solution almost surely on the prescribed interval for any system initial conditions and that the states and the control converge to the origin in a mean-square form within the prescribed time. Then, the controller is redesigned to address the problem of prescribed-time inverse optimal mean-square stabilization. Finally,a concrete example is provided to confirm the efficiency of the proposed design schemes.

关键词： stochastic high-order nonlinear systems prescribed-time stabilization the scaled design inverse optimality

CRABP1-mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells

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Neural Regeneration Research 2024年第6期19卷 1169-1170页

作者： li-na Wei Department of Pharmacology University of Minnesota Medical School

Retinoic acid(RA), the active metabolite of vitamin A(the retinoids), elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Corcoran et al., 2002). The effects of RA are mediated by two very distinct pathways; the first is manifested in the nucleus by binding to a large family of nuclear RA receptors(RARs) to regulate proper expression of RAtargeted genes,

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Artificial intelligence in individualized retinal disease management

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1519-1530页

作者： Zi-ran Zhang Jia-Jun li Ke-ran li The Affiliated Eye Hospital of nanjing Medical University Nanjing 210029Jiangsu ProvinceChina nanjing Medical University Nanjing 210029Jiangsu ProvinceChina

Owing to the rapid development of modern computer technologies,artificial intelligence(AI)has emerged as an essential instrument for intelligent analysis across a range of *** has been proven to be highly effective in ophthalmology,where it is frequently used for identifying,diagnosing,and typing retinal *** increasing number of researchers have begun to comprehensively map patients’retinal diseases using AI,which has made individualized clinical prediction and treatment *** include prognostic improvement,risk prediction,progression assessment,and interventional therapies for retinal *** have used a range of input data methods to increase the accuracy and dependability of the results,including the use of tabular,textual,or image-based input *** also combined the analyses of multiple types of input *** give ophthalmologists access to precise,individualized,and high-quality treatment strategies that will further optimize treatment outcomes,this review summarizes the latest findings in AI research related to the prediction and guidance of clinical diagnosis and treatment of retinal diseases.

关键词： artificial intelligence artificial intelligence in ophthalmology retinal disease

Measurement of acceleration and angular velocity of particles during a 3D silo discharge

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颗粒学报（英文版） 2024年第9期92卷 61-71页

作者： Tongtong Mu Yiming li Quan Chen ran li Hui Yang College of Medical Instrument Shanghai University of Medicine and Health SciencesShanghai201318China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China College of Medical Instrument Shanghai University of Medicine and Health SciencesShanghai201318China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China

Accurate measurement of the three-dimensional(3D)movement of discrete particles is crucial for comprehending complex granular theology in *** this paper,the acceleration and angular velocity of particles in 3D silos are measured by using a spherical detector based on inertial technology and mag-netic positioning *** acceleration of particles is the largest in the center of silos,which suggest that the resistance generated by friction and extrusion is the ***,the angular velocity distribution follows lognormal function except for particles near the *** correlation between acceleration and angular velocity is opposite in different flow *** reveals for the first time that the extent to which the resultant force on the particles affects their rotational motion is related to the flow *** results have practical significance for regulating the granular flow pattern and optimizing the structural design of silos.

关键词： Acceleration Angular velocity Granular flow Silo

Partial linear Model Averaging Prediction for Longitudinal Data

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Journal of Systems Science & Complexity 2024年第2期37卷 863-885页

作者： li na FEI Yu ZHANG Xinyu Faculty of Science Kunming University of Science and TechnologyKunming 650500China School of Statistics and Mathematics Yunnan University of Finance and EconomicsKunming 650221China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Prediction plays an important role in data *** averaging method generally provides better prediction than using any of its *** though model averaging has been extensively investigated under independent errors,few authors have considered model averaging for semiparametric models with correlated *** this paper,the authors offer an optimal model averaging method to improve the prediction in partially linear model for longitudinal *** model averaging weights are obtained by minimizing criterion,which is an unbiased estimator of the expected in-sample squared error loss plus a *** properties,including asymptotic optimality and consistency of averaging weights,are established under two scenarios:(i)All candidate models are misspecified;(ii)Correct models are available in the candidate *** studies and an empirical example show that the promise of the proposed procedure over other competitive methods.

关键词： Asymptotic optimality longitudinal data model averaging estimator partially linear model prediction

Optimization study of spherical tuyere based on BP neural network and new evaluation index

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Building Simulation 2024年第2期17卷 223-234页

作者： Mengchao liu ran Gao Yi Wang Angui li School of Building Services Science and Engineering Xi’an University of Architecture and TechnologyXi’an710055China

The energy consumption of heating,ventilation,and air conditioning(HVAC)systems holds a significant position in building energy usage,accounting for about 65%of the total energy ***,with the advancement of building automation,the energy consumption of ventilation systems continues to *** study focuses on improving the performance of spherical tuyeres in HVAC *** primarily utilizes neural networks and multi-island genetic algorithms(MIGA)for multi-parameter *** employing methods such as structural parameterization,accurate and fast computational fluid dynamics(CFD)simulations,a minimized sample space,and a rational optimization strategy,the time cycle of the optimization process is ***,a new comprehensive evaluation index is proposed in this research to describe the performance of spherical tuyeres,which can be used to more accurately assess spherical tuyeres with different *** results show that by establishing a neural network prediction model and combining it with the multi-island genetic algorithm,a novel spherical tuyere design was successfully *** optimized novel spherical tuyeres achieved a 27.05%reduction in the spherical tuyeres effective index(STEI)compared to the traditional spherical ***,the resistance decreased by 15.68%,and the jet length increased by 7.57%.The experimental results demonstrate that our proposed optimization method exhibits high accuracy,good generalization capability,and excellent agreement at different Reynolds numbers.

关键词： spherical tuyeres STEI CFD ventilation

On m-ovoids of finite classical polar spaces with an irreducible transitive automorphism group

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Science China Mathematics 2024年第3期67卷 683-712页

作者： Tao Feng Weicong li ran Tao School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics and national Center for Applied Mathematics Shenzhen Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Cryptologic Technology and Information Security Ministry of EducationShandong UniversityQingdao 266237China School of Cyber Science and Technology Shandong UniversityQingdao 266237China

In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite familie... 详细信息

关键词： transitive m-ovoids irreducible action finite classical polar spaces primitive divisor