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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 *** analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study *** 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 *** results show that the influence of the Hainan mantle plume on younger volcanic activities(13 Ma)at the same location in the Southeast Asian *** 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 *** 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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Research on internal gravity waves in the Martian atmosphere based on Tianwen-1 and Mars Global Surveyor occultation data

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Earth and Planetary Physics 2024年第6期8卷 890-898页

作者： Luo Xiao CunYing Xiao Xiong Hu zewei wang XiaoQi Wu Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China School of Physics and Astronomy Beijing Normal UniversityBeijing 100875China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100045China Key Laboratory of Science and Technology on Environmental Space Situation Awareness National Space Science CenterChinese Academy of SciencesBeijing 100190China

Internal gravity waves(IGWs)are critical in driving Martian atmospheric motion and *** study investigates Martian IGWs by using high-resolution data from China’s Tianwen-1 mission and the National Aeronautics and Space Administration’s Mars Global Surveyor(MGS)by the radio occultation(RO)*** IGW parameters,such as vertical and horizontal wavelengths,intrinsic frequency,and energy density,are extracted based on vertical temperature profiles from the Martian surface to~50 km *** reveal that the Martian IGWs are predominantly small-scale waves,with vertical wavelengths between 6 and 13 km and horizontal wavelengths extending to thousands of *** waves propagate almost vertically and exhibit low intrinsic frequencies close to the inertial frequency,with the characteristic of low-frequency inertial ***-1 data indicate stronger IGW activity,higher energy density,and less dissipation than MGS data in the northern ***,MGS data in the southern hemisphere show higher buoyancy frequencies and lower vertical wavelengths,suggesting more stable atmospheric conditions conducive to IGW *** extracted IGW characteristics can enhance our understanding of the atmospheric dynamics on Mars and contribute valuable information for parameterization in global circulation models.

关键词： internal gravity waves Mars Tianwen-1 Mars Global Surveyor radio occultation

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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 *** 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 ***,the Tethyan lithosphere did not disappear but rather continued to evolve after entering into the deep *** 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 *** 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 *** 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 *** 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 *** 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 *** western portion of the Tethyan anomaly may reflect remnants of Paleo-Tethys,while the eastern portion,tow

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 *** has been widely used in various image classification *** 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 *** deformable images such as human faces,pixels at the same location of different images of the same subject usually have different ***,extracting features and correctly classifying such deformable objects is very ***,the lighting,attitude and occlusion cause more *** the problems and challenges listed above,a novel image representation and classification algorithm is ***,the authors’algorithm generates virtual samples by a non-linear variation *** method can effectively extract the low-frequency information of space-domain features of the original image,which is very useful for representing deformable *** combination of the original and virtual samples is more beneficial to improve the clas-sification performance and robustness of the ***,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 *** weighting coefficients in the score fusion scheme are set entirely ***,the algorithm classifies the samples based on the final *** 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 *** a deformable sample classification task,face recognition is often used to test the performance of classification *** face recognition,differences in expression,angle,posture,and lighting conditions have become key factors that affect recognition ***,there may be significant differences between different image samples of the same face,which makes image classification very ***,how to build a robust virtual image representation becomes a vital *** solve the above problems,this paper proposes a novel image classification ***,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 ***,by the principle of sparse representation,the linear expression coefficients of the original sample and the virtual sample can be calculated,*** 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 *** two distances are converted into distance ***,a simple and effective weight fusion scheme is adopted to fuse the classification scores of the original image and the virtual *** fused score will determine the final classification *** experimental results show that the proposed method outperforms other typical sparse representation classification methods.

关键词： representation sample image

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硬质合金四齿立铣刀结构优化设计

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天津理工大学学报 2025年第2期41卷 13-20页

作者：董黎敏林锌洛王泽巍尚晓帅贠良天津理工大学天津市先进机电系统设计与智能控制重点实验室天津理工大学机电工程国家级实验教学示范中心天津市宏维刀具有限公司

针对普通硬质合金四齿立铣刀在加工过程中存在的排屑不顺、刀齿易磨损等缺陷，文中对普通硬质合金四齿立铣刀结构进行了结构优化，扩大立铣刀刀头角度及螺旋槽的螺旋角，增大容屑槽的角度，改进螺旋槽槽底的形状，设计了结构优化后的强... 详细信息

针对普通硬质合金四齿立铣刀在加工过程中存在的排屑不顺、刀齿易磨损等缺陷，文中对普通硬质合金四齿立铣刀结构进行了结构优化，扩大立铣刀刀头角度及螺旋槽的螺旋角，增大容屑槽的角度，改进螺旋槽槽底的形状，设计了结构优化后的强力四齿立铣刀；在Pro/E三维建模软件中建立了普通和结构优化后的两种立铣刀的三维模型，运用Ansys有限元分析软件对两种立铣刀进行切削性能分析。结果表明，经过结构优化设计得到的强力四齿立铣刀，其削性能显著提高。

关键词：硬质合金四齿立铣刀三维建模有限元分析结构优化设计

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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 *** 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 *** surgery is the preferred method of treatment for AM,other therapeutic options may be employed based on the stage and underlying etiology of the *** checkpoint inhibitors,molecular targeted therapy,radiotherapy,chemotherapy,and oncolytic virotherapy represent promising advanced treatment options for *** 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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Isolation and oral immunogenicity assessment of porcine epidemic diarrhea virus NH-TA2020 strain:One of the predominant strains circulating in China from 2017 to 2021

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Virologica Sinica 2022年第5期37卷 646-655页

作者： Xiaowen Li Yang Li Jiapei Huang Yali Yao Wenying Zhao Yunjing Zhang Jie Qing Jing Ren Zhong Yan zewei wang Xiaofang Hu Duli Kang Hongqiang Liu Zhichun Yan New Hope Liuhe Co. Ltd.Chengdu610041China National Research Center for Veterinary Medicine Luoyang471000China Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co. Ltd.(NHLH Academy of Swine Research)Dezhou253034China Swine Health Data and Intelligent Monitoring Project Laboratory Dezhou UniversityDezhou253011China Pulike Biological Engineering Inc. Luoyang471000China

Porcine epidemic diarrhea(PED)caused by porcine epidemic diarrhea virus(PEDV)is one of the most devastating diseases in the global pig industry due to its high mortality rate in *** vaccines can effectively enhance the gut-mammary gland-secretory IgA axis to boost lactogenic immunity and passive protection of nursing piglets against PEDV *** 2017 to 2021,we collected 882 diarrhea samples from 303 farms in China to investigate the epidemiology of *** result showed that about 52.15%(158/303)of the farms were positive for PEDV with an overall detection rate of 63.95%(564/882)of the *** S1 fragments of S gene from 104 strains were sequenced for the phylogenetic analysis.A total of 71 PEDV strains(68.27%)sequenced in this study were clustered into the predominant G2c subgroup,while the newly-defined G2d strains(9.62%)were identified in three provinces of *** NH-TA2020 strain of G2c subgroup was isolated and cultured,and its infection to piglets caused watery diarrhea within 24 h,indicating its strong *** administration of NH-TA2020 strain to pregnant gilts stimulated high levels of IgA antibody in *** piglets fed by the gilts above were challenged with NH-TA2020 strain or CH-HeB-RY-2020 strain from G2d subgroup,and the clinical symptoms and virus shedding were significantly reduced compared to the mock *** findings suggest that G2c subgroup is the predominant branch circulating in China from 2017 to *** administration of NH-TA2020 enhances maternal IgA and lactogenic immune responses,which confer protection against the homologous and emerging G2d PEDV strains challenges in neonates.

关键词： Porcine epidemic diarrhea virus(PEDV) Molecular epidemiological investigation Virus isolation Lactogenic immune IgA

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知识生产视角下应急管理学科建设的使命与路径

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中国安全科学学报 2022年第2期32卷 1-9页

作者：谭爽许明欣王泽玮中国矿业大学(北京)文法学院北京100083

为厘清应急管理学科建设机制、推进应急管理学科良性发展,通过回顾学科建设历史,来分析应急管理学科建设面临的困境与肩负的使命,并提出相应的建设路径。研究表明:在知识生产模式转型视角下,应急管理学科建设面临知识生产者离散、知识... 详细信息

为厘清应急管理学科建设机制、推进应急管理学科良性发展,通过回顾学科建设历史,来分析应急管理学科建设面临的困境与肩负的使命,并提出相应的建设路径。研究表明:在知识生产模式转型视角下,应急管理学科建设面临知识生产者离散、知识创新度不足、知识转化率有限的三重困境,需要完成“朝向人才培养的应急管理知识直接再生产”“朝向科学研究的应急管理知识扩大再生产”和“朝向社会服务的应急管理知识转化再生产”的三大使命,并从做好应急管理学科顶层设计、优化应急管理人才培养体系、推动应急管理科研协同创新、提升应急管理社会服务能力4条路径入手,提升学科建设成效。

关键词：知识生产应急管理学科建设人才培养科学研究社会服务

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基于卷积变分自编码和多头自注意力机制的断路器剩余机械寿命预测

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仪器仪表学报 2024年第3期45卷 106-118页

作者：孙曙光王泽伟陈静黄光临王景芹河北工业大学人工智能与数据科学学院天津300130 温州聚星科技股份有限公司温州325062 河北工业大学省部共建电工装备可靠性与智能化国家重点实验室天津300130

针对万能式断路器退化过程的不确定性,考虑到振动信号对机械性能退化的完善表征,提出了一种基于卷积变分自编码(CVAE)和多头自注意力机制(MSA)的断路器分闸机械机构寿命预测方法。首先依据断路器不同的事件区间提取参数特征,再通过CVAE... 详细信息

针对万能式断路器退化过程的不确定性,考虑到振动信号对机械性能退化的完善表征,提出了一种基于卷积变分自编码(CVAE)和多头自注意力机制(MSA)的断路器分闸机械机构寿命预测方法。首先依据断路器不同的事件区间提取参数特征,再通过CVAE挖掘信号成分中的深度特征,将参数特征与深度特征融合得到完备退化特征,最后建立GRU-MSA的定量寿命预测模型,引入了多头自注意力机制,在多个不同表征子空间中捕捉信号的不同依赖关系,对重要的时间步赋予更大的权重。最后利用3台试品的振动信号测量数据对所提断路器分闸机械机构寿命预测方法进行测试,结果表明,所提出的方法在3个数据集中寿命预测均方根误差(RMSE)分别为141.46、128.75和134.16,平均绝对误差(MAE)分别为112.17、101.52和106.22,预测精度高且稳定性好,相对于其他混合预测模型更具优势。

关键词：万能式断路器卷积变分自编码多头自注意力机制剩余寿命预测

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