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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying zhu Hesong Wang Anzhi Zhang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Forestry and Landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

Inverse Construction Methods of Heterogeneous NURBS Object Based on Additive Manufacturing

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Computer Modeling in Engineering & Sciences 2020年第11期125卷 597-610页

作者： ting Zang Dongbin zhu Guowang Mu School of Science Hebei University of TechnologyTianjin300130China School of Mechanical Engineering Hebei University of TechnologyTianjin300130China

According to the requirement of heterogeneous object modeling in additive manufacturing(AM),the Non-Uniform Rational B-Spline(NURBS)method has been applied to the digital representation of heterogeneous object in this *** putting forward the NURBS material data structure and establishing heterogeneous NURBS object model,the accurate mathematical unified representation of analytical and free heterogeneous objects have been *** the inverse modeling of heterogeneous NURBS objects,the geometry and material distribution can be better designed to meet the actual *** Basis Function(RBF)method based on global surface reconstruction and the tensor product surface interpolation method are combined to RBF-NURBS inverse construction *** geometric and/or material information of regular mesh points is obtained by RBF interpolation of scattered data,and the heterogeneous NURBS surface or object model is obtained by tensor product *** examples have shown that the heterogeneous objects fitting to scattered data points can be generated effectively by the inverse construction methods in this paper and 3D CAD models for additive manufacturing can be provided.

关键词： NURBS heterogeneous object inverse construction method RBF scattered data points

Chiral Sulfinamide-Olefin Ligands： Switchable Selectivity in Rhodium-Catalyzed Asymmetric 1,2-Addition of Arylboronic Acids to Aliphatic α-Ketoesters

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Chinese Journal of Chemistry 2013年第3期31卷 321-328页

作者： ting-Shun zhu Ming-Hua Xu Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China

Simple and readily available chiral N-（sulfinyl）allylamines have been developed as efficient novel ligands for the rhodium-catalyzed enantioselective 1,2-addition of arylboronic acids to challenging aliphatic a-ketoesters. By employing the linear or branched sulfinamide-olefin ligands, interesting enantioselectivity as well as regioselectiw ity reversal in the related asymmetric additions were observed.

关键词： asymmetric catalysis rhodium sulfur-o|efin ligand 1,2-addition stereoselectivity reversal

Reliability evaluation of modular multilevel converter based on Markov model

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1355-1363页

作者： Liang ZHANG Dan ZHANG ting HUA Jihong zhu Gang CHEN Tongzhen WEI ting YANG School of Power Electric Engineering Nanjing Institute of TechnologyNanjing 211167China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing 100084China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Grid Jiangsu Electric Power Company Xuzhou Power Supply Company Xuzhou 221005China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China

The modular multilevel converter(MMC)is now the most attractive topology for medium and high voltage power conversion applications with several advantages over the traditional voltage source converter(VSC).However,due to a large number of sub-modules(SMs)in the MMC,system reliability is a big challenge in its practical application,where each SM may be considered as a potential point of *** this paper,a reliability evaluation based on the Markov model is proposed for the *** failure rates of the power electronic devices and SMs are firstly ***,the Markov model and the state transition equation of the system are built in detail.A general reliability evaluation function is established,in which the mean time to failure and reliability evaluation of the MMC with redundant SMs are also ***,a practical direct current(DC)distribution example for reliability evaluation is analyzed,and the results verify that the reliability evaluation based on the Markov model could provide a useful reference for project design.

关键词： Modular multilevel converters Reliability evaluation Markov model

Green building materials lit up by electromagnetic absorption function:A review

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Journal of Materials Science & Technology 2022年第17期112卷 329-344页

作者： ting-ting Liu Mao-Qing Cao Yong-Sheng Fang Yu-Hang zhu Mao-Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Heilongjiang Institute of Construction Technology Harbin 150025China

Healthy and livable living environments,as well as anti-electromagnetic(EM)radiation buildings,are the long-term goals of human *** introduction of advanced EM wave absorbing materials into buildings is one of the most feasible ways to address the increasing EM pollution in building ***-efficiency,broadband,low-cost and good building performance EM wave absorbing materials,as an important support in the field of sustainable building,has gradually become the hotspot ***,we review the research progress of building materials with EM wave absorption functions,and comb their classification,including cement,concrete,ceramics,and prefabs,especially highlighting the advanced coating *** objectively outline and evaluate the latest technology of building materials with EM wave absorption performance,and discuss the main problems and bottlenecks,highlighting potential research opportunities.

关键词： Anti-electromagnetic radiation building Electromagnetic wave absorption Building materials Green building

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe Sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

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

Dropout training for SVMs with data augmentation

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Frontiers of Computer Science 2018年第4期12卷 694-713页

作者： Ning CHEN Jun zhu Jianfei CHEN ting CHEN MOE Key lab of Bioinformatics Bioinformatics Division and Center for Synthetic and Systems Biology TNLIST Tsinghua University Beijing 100084 China State Key Lab of Intelligent Technology and Systems Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Dropout and other feature noising schemes have shown promise in controlling over-fitting by artificially corrupting the training data. Though extensive studies have been performed for generalized linear models, little has been done for support vector machines （SVMs）, one of the most successful approaches for supervised learning. This paper presents dropout training for both linear SVMs and the nonlinear extension with latent representation learning. For linear SVMs, to deal with the intractable expectation of the non-smooth hinge loss under corrupting distributions, we develop an iteratively re-weighted least square （IRLS） algorithm by exploring data augmentation techniques. Our algorithm iteratively minimizes the expectation of a re- weighted least square problem, where the re-weights are analytically updated. For nonlinear latent SVMs, we con- sider learning one layer of latent representations in SVMs and extend the data augmentation technique in conjunction with first-order Taylor-expansion to deal with the intractable expected hinge loss and the nonlinearity of latent representa- tions. Finally, we apply the similar data augmentation ideas to develop a new IRLS algorithm for the expected logistic loss under corrupting distributions, and we further develop a non-linear extension of logistic regression by incorporating one layer of latent representations. Our algorithms offer insights on the connection and difference between the hinge loss and logistic loss in dropout training. Empirical results on several real datasets demonstrate the effectiveness of dropout training on significantly boosting the classification accuracy of both linear and nonlinear SVMs.

关键词： dropout SVMs logistic regression data aug- mentation iteratively reweighted least square

Super-resolution reconstruction of astronomical images using time-scale adaptive normalized convolution

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Chinese Journal of Aeronautics 2018年第8期31卷 1752-1763页

作者： Rui GUO Xiaoping SHI Yi zhu ting YU Control and Simulation Center Harbin Institute of Technology Harbin 150080 China Tianjin Branch of China Petroleum Pipeline Engineering Company Limited Tianjin 300457 China

In this work, we describe a new multiframe Super-Resolution（SR） framework based on time-scale adaptive Normalized Convolution（NC）, and apply it to astronomical images. The method mainly uses the conceptual basis of NC where each neighborhood of a signal is expressed in terms of the corresponding subspace expanded by the chosen polynomial basis function. Instead of the conventional NC, the introduced spatially adaptive filtering kernel is utilized as the applicability function of shape-adaptive NC, which fits the local image structure information including shape and orientation. This makes it possible to obtain image patches with the same modality,which are collected for polynomial expansion to maximize the signal-to-noise ratio and suppress aliasing artifacts across lines and edges. The robust signal certainty takes the confidence value at each point into account before a local polynomial expansion to minimize the influence of ***, the temporal scale applicability is considered to omit accurate motion estimation since it is easy to result in annoying registration errors in real astronomical applications. Excellent SR reconstruction capability of the time-scale adaptive NC is demonstrated through fundamental experiments on both synthetic images and real astronomical images when compared with other SR reconstruction methods.

关键词： Astronomical image processing Motion estimation Normalized Convolution(NC) Polynomial expansion Signal-to-noise ratio Super-Resolution (SR)reconstruction