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Mantle sources of Cenozoic volcanoes around the South China Sea revealed by geochemical and isotopic data using the principal component analysis

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Journal of Oceanology and Limnology 2023年第2期41卷 562-574页

作者： Shuangshuang CHEN Zewei Wang Rui GAO Yongzhang ZHOU School of Earth Sciences and Engineering Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Guangdong Provincial Key Lab of Geological Processes and Mineral Resources Guangzhou 510275China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan Island,Fujian-Zhejiang coast,Taiwan Island),and parts of Vietnam and Thailand.We analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study region.Two principal components(PCs)were extracted by PCA based on the trace elements and Sr-Nd-Pb isotopic ratios,which probably indicate an enriched oceanic island basalt-type mantle plume and a depleted mid-ocean ridge basalt-type spreading ridge.The results show that the influence of the Hainan mantle plume on younger volcanic activities(13 Ma)at the same location in the Southeast Asian region.PCA was employed to verify the mantle-plume-ridge interaction model of volcanic activities beneath the expansion center of SCS and refute the hypothesis that the tension of SCS is triggered by the Hainan plume.This study reveals the efficiency and applicability of PCA in discussing mantle sources of volcanic activities;thus,PCA is a suitable research method for analyzing geochemical data.

关键词： volcanic rocks geochemical indicators mantle source principal component analysis South China Sea

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Global seismic tomography reveals remnants of subducted Tethyan oceanic slabs in the deep mantle

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Science China Earth Sciences 2023年第12期66卷 2751-2769页

作者： Zewei Wang Jiashun HU Xueyang BAO Chunquan YU Yingjie YANG Xiaofei CHEN Guangdong Provincial Key Laboratoryof Geophysical High-resolution Imaging Technology Southern University of Science and Technology Shenzhen 518055China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China

The Tethyan evolution depicts the continuous process of landmasses separating from the Gondwana continent in the south,drifting northwards,and subsequently colliding with the continents in the north over the past 500 million years.In this process,the Tethyan oceans that formed between the landmass and the southern or northern continents underwent growth,evolution,and eventual closure with the early Cenozoic India-Eurasia collision.However,the Tethyan lithosphere did not disappear but rather continued to evolve after entering into the deep Earth.The current position,morphology,and volume of the subducted Tethyan oceanic slabs in the deep mantle record the latest moment of this continuous evolution,providing critical constraints for Tethyan studies.This paper summarizes and analyzes the results of global-scale whole-mantle seismic tomography in the past nearly two decades,revealing a northwest-southeast seismically high-velocity anomaly,which is linearly distributed at depths of 1000–2000 km beneath the Tethyan realm and referred to as the Tethyan anomaly.By searching for an optimal linear combination of previous global seismic tomographic models to best match the known subducted slabs in the upper mantle,we observe that the Tethyan anomaly extends approximately 8700 km in length and 2600 km in width,exhibiting a parallel structure with northern and southern branches.Combining geological records of oceanic subduction initiation and previous geodynamic studies,this study suggests that the main body of the Tethyan anomaly represents the remnants of the subducted Neo-Tethyan oceanic slabs,which subducted from the Late Jurassic to the early Cenozoic.The northern branch consists of subducted slabs from the Neo-Tethys beneath the southern margin of Eurasia,while the southern branch likely reflects the intra-oceanic subducted slabs of Neo-Tethys during the Cretaceous.The western portion of the Tethyan anomaly may reflect remnants of Paleo-Tethys,while the eastern portion,towards India and the Bay of Bengal,shows signs of

关键词： Global seismic tomography Tethyan evolution Oceanic slabs Lower-mantle structure High-velocity anomaly

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Sparse representation scheme with enhanced medium pixel intensity for face recognition

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 116-127页

作者： Xuexue Zhang Yongjun Zhang Zewei Wang Wei Long Weihao Gao Bob Zhang State Key Laboratory of Public Big Data Institute for Artificial IntelligenceCollege of Computer Science and TechnologyGuizhou UniversityGuiyangGuizhouChina Department of Computer and Information Science University of MacaoAvenida da UniversidadeTaipaMacaoChina

Sparse representation is an effective data classification algorithm that depends on the known training samples to categorise the test sample.It has been widely used in various image classification tasks.Sparseness in sparse representation means that only a few of instances selected from all training samples can effectively convey the essential class-specific information of the test sample,which is very important for classification.For deformable images such as human faces,pixels at the same location of different images of the same subject usually have different intensities.Therefore,extracting features and correctly classifying such deformable objects is very hard.Moreover,the lighting,attitude and occlusion cause more difficulty.Considering the problems and challenges listed above,a novel image representation and classification algorithm is proposed.First,the authors’algorithm generates virtual samples by a non-linear variation method.This method can effectively extract the low-frequency information of space-domain features of the original image,which is very useful for representing deformable objects.The combination of the original and virtual samples is more beneficial to improve the clas-sification performance and robustness of the algorithm.Thereby,the authors’algorithm calculates the expression coefficients of the original and virtual samples separately using the sparse representation principle and obtains the final score by a designed efficient score fusion scheme.The weighting coefficients in the score fusion scheme are set entirely automatically.Finally,the algorithm classifies the samples based on the final scores.The experimental results show that our method performs better classification than conventional sparse representation algorithms.

关键词： computer vision face recognition image classification image representation

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Application of improved virtual sample and sparse representation in face recognition

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1391-1402页

作者： Yongjun Zhang Zewei Wang Xuexue Zhang Zhongwei Cui Bob Zhang Jinrong Cui Lamin LJanneh College of Computer Science and Technology Guizhou UniversityGuiyangChina Big Data Science and Intelligent Engineering Research Institute Guizhou Education UniversityGuiyangChina School of Mathematics and Big Data Guizhou Education UniversityGuiyangChina Department of Computer and Information Science University of MacaoAvenida da UniversidadeTaipaMacaoChina School of Mathematics and Information South China Agricultural UniversityGuangzhouChina

Sparse representation plays an important role in the research of face recognition.As a deformable sample classification task,face recognition is often used to test the performance of classification algorithms.In face recognition,differences in expression,angle,posture,and lighting conditions have become key factors that affect recognition accuracy.Essentially,there may be significant differences between different image samples of the same face,which makes image classification very difficult.Therefore,how to build a robust virtual image representation becomes a vital issue.To solve the above problems,this paper proposes a novel image classification algorithm.First,to better retain the global features and contour information of the original sample,the algorithm uses an improved non‐linear image representation method to highlight the low‐intensity and high‐intensity pixels of the original training sample,thus generating a virtual sample.Second,by the principle of sparse representation,the linear expression coefficients of the original sample and the virtual sample can be calculated,respectively.After obtaining these two types of coefficients,calculate the distances between the original sample and the test sample and the distance between the virtual sample and the test sample.These two distances are converted into distance scores.Finally,a simple and effective weight fusion scheme is adopted to fuse the classification scores of the original image and the virtual image.The fused score will determine the final classification result.The experimental results show that the proposed method outperforms other typical sparse representation classification methods.

关键词： representation sample image

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Visible light-driven oxidant-free dehydrogenation of alcohols in water using porous ultrathin g-C_(3)N_(4)nanosheets

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Green Energy & Environment 2022年第4期7卷 712-722页

作者： Wei Zhang Jiajun wang zewei Liu Yibing Pi Rong Tan National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education)College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha410081China

Graphitic carbon nitride(g-C_(3)N_(4)) is a fascinating photocatalyst for solar energy utilization in photo-catalysis.Nevertheless,it often suffers from moderate photo-catalytic activity due to its low specific surface area and fast recombination rate of photogenerated electrons upon photo-excitation.Herein,we overcome the bottlenecks by constructing a porous g-C_(3)N_(4) nanosheet(PCNS)through a simple thermal oxidation etching method.Benefited from its porous layer structure,the obtained PCNS exhibits large specific surface area,efficient separation of photogenerated charge carriers,as well as high exposure of active sites.As a result,it is robust and universal in visible light-driven dehydrogenation of alcohols in water under oxidant-free condition.Almost quantitative yields(>99%)of various valuable carbonyl compounds were obtained over PCNS,while bulk g-C_(3)N_(4) was far less efficient.Moreover,the photo-catalyst was highly stable and could be facilely recovered from the aqueous system for efficient reuse.The easy preparation and excellent performance made PCNS a promising and competitive photocatalyst for the solar applications.

关键词： Photo-catalysis Porous g-C_(3)N_(4)nanosheets Visible light irradiation Oxidant-free dehydrogenation Alcohols

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Prediction of load-displacement performance of grouted anchors in weathered granites using FastICA-MARS as a novel model

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Geoscience Frontiers 2021年第1期12卷 415-423页

作者： Hao Shen Jinhui Li Sixin wang zewei Xie Department of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen518055China Shenzhen Institute of Building Research Co. Ltd.Shenzhen518049China

With the rising needs of better prediction of the load-displacement performance of grouted anchors in an era of developing large-scale underground infrastructures,the existing methods in literature lack an accurate analytical model for the real-life projects or rigorous understanding of the parameters such as grouting pressures.This paper proposes Fast ICA-MARS as a novel data-driven approach for the prediction of the load-displacement performance of uplift-resisting grouted anchors.The hybrid and data-driven Fast ICA-MARS approach integrates the multivariate adaptive regression splines(MARS)technique with the Fast ICA algorithm which is for Independent Component Analysis(ICA).A database of 4315 observations for 479 different anchors from 7 different projects is established.The database is then used to train,validate and compare the Fast ICA-MARS approach with the classical MARS approach.The developed Fast ICA-MARS model can provide more accurate predictions than MARS.Moreover,the developed Fast ICA-MARS model is easy to interpret since the evaluation of the parameter importance of the independent components can be conducted along with the considerations of the correlations with the original variables.It is noteworthy to point out that the grouting pressures play a central role in the proposed model,which is considered of paramount importance in engineering practices but has not been properly taken into account in any prior analytical or empirical predictive models for the load-displacement relationships.

关键词： Grouted anchors Load-displacement relationships Pull-out tests FastICA MARS

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Evolutionary Decision-Making and Planning for Autonomous Driving Based on Safe and Rational Exploration and Exploitation

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Engineering 2024年第2期33卷 108-120页

作者： Kang Yuan Yanjun Huang Shuo Yang zewei Zhou Yulei wang Dongpu Cao Hong Chen College of Electronic and Information Engineering Tongji UniversityShanghai 201804China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201210China School of Automotive Studies Tongji UniversityShanghai 201804China School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China

Decision-making and motion planning are extremely important in autonomous driving to ensure safe driving in a real-world environment.This study proposes an online evolutionary decision-making and motion planning framework for autonomous driving based on a hybrid data-and model-driven method.First,a data-driven decision-making module based on deep reinforcement learning(DRL)is developed to pursue a rational driving performance as much as possible.Then,model predictive control(MPC)is employed to execute both longitudinal and lateral motion planning tasks.Multiple constraints are defined according to the vehicle’s physical limit to meet the driving task requirements.Finally,two principles of safety and rationality for the self-evolution of autonomous driving are proposed.A motion envelope is established and embedded into a rational exploration and exploitation scheme,which filters out unreasonable experiences by masking unsafe actions so as to collect high-quality training data for the DRL agent.Experiments with a high-fidelity vehicle model and MATLAB/Simulink co-simulation environment are conducted,and the results show that the proposed online-evolution framework is able to generate safer,more rational,and more efficient driving action in a real-world environment.

关键词： Autonomous driving Decision-making Motion planning Deep reinforcement learning Model predictive control

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Recent advancements in the diagnosis and treatment of acral melanoma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第2期25卷 106-122页

作者： Ahmad ALHASKAWI Sohaib Hasan Abdullah EZZI Yanzhao DONG Haiying ZHOU Zewei Wang Jingtian LAI Chengjun YAO Vishnu Goutham KOTA Mohamed Hasan Abdulla Hasan ABDULLA Hui LU Department of Orthopedics the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou310003China Department of Orthopaedics Third Xiangya HospitalCentral South UniversityChangsha410013China Zhejiang University School of Medicine Hangzhou310058China Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare Zhejiang UniversityHangzhou310058China

Acral melanoma(AM)is the most common histologic subtype of melanoma in dark-skinned patients and is associated with a worse prognosis and a high mortality rate,largely due to the inconspicuous nature of early-stage lesions,which can lead to late diagnosis.Because of the overlapping clinical and histopathological features of AM with other forms of cutaneous melanomas,early detection of AM requires a multidisciplinary approach that integrates various diagnostic modalities,including clinical examination,dermoscopy,histopathology,molecular testing,radiological imaging,and blood tests.While surgery is the preferred method of treatment for AM,other therapeutic options may be employed based on the stage and underlying etiology of the disease.Immune checkpoint inhibitors,molecular targeted therapy,radiotherapy,chemotherapy,and oncolytic virotherapy represent promising advanced treatment options for AM.In this review,we provide an overview of the latest advancements in diagnostic and therapeutic methods for AM,highlighting the importance of early detection and the prompt,individualized management of this challenging disease.

关键词： Acral melanoma Acral lentiginous melanoma Acral nevus Cutaneous malignant melanoma Dermoscopy Oncolytic virotherapy

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Highly doped NaErF_(4)-based nanocrystals for multi-tasking application

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Journal of Rare Earths 2021年第12期39卷 1467-1476,I0001页

作者： Yulin Xie Qing Chen Man wang Weilin Chen zewei Quan Chunxia Li Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinarity ScienceShandong UniversityQingdao 266237China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

How to engineer single nanocrystal to achieve multiple functions is still a huge challenge.In this work,a novel highly doped rare earth nanocrystal NaErF_(4)@NaGdF_(4)@NaDyF_(4)(Er@Gd@Dy)was designed and fabricated,which exhibits various performances by itself,including the longitudinal(T1)and transverse relaxation time(T2)double-mode magnetic resonance imaging(MRI),upconversion luminescence and down-shifting luminescence.Upon irradiation of 808 nm near-infrared(NIR)light,the upconverted red light can indirectly activate the photo sensitizer Ce6 conjugated on the surface of nanocrystals for photodynamic therapy(PDT).In vivo experiments demonstrate that the nano materials can eradicate notably primary tumors without obvious systematic toxicity.In addition,the longitudinal and transverse relaxation rates of Er@Gd@Dy are 24.83 and 319.86(mmol/L)^(-1)/s,respectively,which are superior to those of the nanocrystals reported previously.Simultaneously,the nanocrystals have the ability to generate NIR-Ⅱlight located at 1530 nm,favorable in bioimaging in deeper tissues.As a consequence,this new nanoplatform will advance the improvement of multimodal imaging guided tumor diagnosis and treatment.

关键词： Rare earth nanocrystals MRI Upconversion NIR-Ⅱwindow Photodynamic therapy

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Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in Tropical Area of China

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Chinese Journal of Population,Resources and Environment 2012年第3期10卷 100-106页

作者： Meng Qingyan Miao zewei wang Zhaoqian Beijing Normal University Beijing 100875China Institute of Remote Sensing Applications Chinese Academy of SciencesBeijing100101China Dpartment of Agricultural and Biological Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801the United States Agro-Ecology Research Institute Zhejiang UniversityHangzhou Zhejiang 310029China

As a typical tropical agro-forestry ecosystem in Wenchang,Hainan Province,China,rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index,stability indicator,harmonizing coefficient,grey correlation coefficient and production dominance.This study focused on rational hierarchical structure,the limiting factors and optimal strategies of the model development based on model structure,resource conditions and external market demands.Results showed that rational mechanism of the rubber-tea-chicken ecosystem model mainly included technological contributions,leverage function of dominance component(livestock husbandry),stability of the model structure and harmony of its components,the model dominant product's market demand and government's supporting policies.The contributions of fund,technology,information and talent resources played an important role in improving sustainability and productivity of the agro-forestry model.

关键词：农林复合生态系统热带地区机制中国生态农业模式茶鸡模型结构

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