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多组垂直裂缝诱导各向异性的HTI近似及其特征分析

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地球物理学报 2019年第5期62卷 1835-1848页

作者：张安家王赟孙鹏远李添才中国地质大学(北京)地球物理与信息技术学院地质过程与矿产资源国家重点实验室北京100083 东方地球物理公司河北涿州072750 中交铁道设计研究总院有限公司北京100088

在裂缝诱导各向异性理论研究中通常使用等效HTI介质来近似多组裂缝所引起的综合效应.由于构造运动的复杂性,多组裂缝普遍存在于地壳与油气储层中.为了研究多组裂缝的地震属性特征,分析常用的等效HTI模型对于多组裂缝近似精度及附加裂缝... 详细信息

在裂缝诱导各向异性理论研究中通常使用等效HTI介质来近似多组裂缝所引起的综合效应.由于构造运动的复杂性,多组裂缝普遍存在于地壳与油气储层中.为了研究多组裂缝的地震属性特征,分析常用的等效HTI模型对于多组裂缝近似精度及附加裂缝对介质属性特征的影响,本文利用线性滑移模型进行了多组垂直裂缝的单斜各向异性等效介质理论计算,并利用空间搜索方法求取与其最为接近的HTI介质各向异性弹性参数.重点研究了在两种各向异性介质中纵波速度、快慢横波速度和极化特征及其差异,量化分析附加裂缝对于地震属性如速度、极化方向和走时等的影响,研究对附加裂缝敏感的地震属性.此研究结果和方法为进一步研究多组裂缝的反演及识别方法提供基础,同时对于将高阶对称性各向异性介质中已存在的计算方法应用于低阶对称性时的适用程度、精度分析及相关方法研究具有重要作用.

关键词：多组裂缝单斜各向异性等效介质 HTI

ELLIPTICAL ANISOTROPY ABOVE THE CRYSTALLINE BASEMENT FROM WIDE-APERTURE Pg EVENTS

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ELLIPTICAL ANISOTROPY ABOVE THE CRYSTALLINE BASEMENT FROM WI...

中国科学院地质与地球物理研究所2008学术年会

作者： anjia zhang and ZHONGJIE zhang State Key Laboratory of Lithosphere Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,PR.China.

zhang,*** zhang,Z.,*** anisotropy above the crystalline basement from wide aperture Pg ***:Liu,E.,zhang,Z.-*** Li,X.-Y.(Eds.),Seismic Anisotropy. Journal of Seismic Exploration,17:195-208. Traveltime data of Pg events,which are refractions from the crystalline basement(CB) in the controlled-source wide-aperture seismic sections,provide key constraints on the construction of shallow seismic structures above the crystalline *** sedimentary rock is usually considered to be anisotropic because of the preferred alignment of microcracks and thin layering in the upper *** the interpretation of Pg events needs to account for seismic velocity anisotropy. For this reason,it is the prerequisite to establish traveltime-offset relationship for Pg events in anisotropic ***,we first derive a traveltime-offset relationship for Pg waves by assuming a model with a linear velocity increase;then we present a scheme to invert Pg traveltime-offset data for velocity anisotropy in shallow crustal *** compare the Pg traveltimes calculated by our analytic equation with raytracing to test the ***,real data from the deep-seismic reflection profiles in the southeast China are analyzed to demonstrate the potential of our method.

关键词： continuous medium crystalline basement Pg event wide-angle seismic profiling traveltime.

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应用振动噪声的频率谐振效应对地球进行成像

地质论评 2021年第S01期67卷 47-48页

作者：薛爱民李达宋红星张安家北京派特森科技股份有限公司北京100085 武汉科技大学武汉430081

常规的反射地震勘探方法技术已经经过百年时间的发展,但仍然存在许多勘探技术问题难以很好地解决,造成对诸多勘探目标难以精确成像。这些技术性问题包括:浅层勘探盲区、无明显界面地质体、高角度地层以及火成岩与变质岩地区地质体成像等。

关键词：地震勘探频率谐振成像

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电镀钯对锆合金吸氢性能的影响

稀有金属材料与工程 2024年第3期53卷 685-691页

作者：赵立功李江豪郭慧娟杨大稳张岸佳张沛龙周文娇佟欢宋西平北京科技大学新金属材料国家重点实验室北京100083 中石油工程技术研发有限公司北京102206 北京浩运金能新能源材料科技有限公司北京102100

锆具有良好的吸氢性能,被认为是储氘领域的候选材料。但由于其吸氢温度较高且吸氢动力学较慢,目前尚不能进行广泛应用。采用电镀钯的方法对锆进行表面改性,以提高其吸氢性能。结果表明:在经过镀钯且退火处理后的锆合金,在室温下可以实... 详细信息

锆具有良好的吸氢性能,被认为是储氘领域的候选材料。但由于其吸氢温度较高且吸氢动力学较慢,目前尚不能进行广泛应用。采用电镀钯的方法对锆进行表面改性,以提高其吸氢性能。结果表明:在经过镀钯且退火处理后的锆合金,在室温下可以实现吸氢,并且有适当的孕育期;与此同时,随着温度的升高,镀钯且退火处理后的锆合金孕育期缩短,吸氢速率变快。通过对微观结构进行分析,发现在氢化后,钯层与锆基板之间形成了过渡区,过渡区中存在PdH_(1.33)和H_(0.62)Zr_(0.38)。由此可见,过渡区中的氢化物对改善锆的吸氢性能起着重要作用。通过对动力学机制进行研究,确定在室温下,镀钯且退火处理后的锆合金吸氢过程符合一维扩散机制;而在250℃时,符合二维扩散机制。

关键词：锆电镀钯氢吸收温度氢吸收动力学

SUB-TRIANGLE SHOOTING RAY-TRACING IN COMPLEX 3D VTI MEDIA

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SUB-TRIANGLE SHOOTING RAY-TRACING IN COMPLEX 3D VTI MEDIA

昆虫性信息素及其类似物干扰昆虫行为的机理和应用研究进展

中国科学院地质与地球物理研究所2008学术年会

作者： TAO XU~1.ZHONGJIE zhang~1,AIHUA ZHAO~2,anjia zhang~1,XI zhang~1 and HONGSHUANG zhang~1 1 State Key Laboratory of Lithosphere Evolution,Institute of Geology and Geophysics.Chinese Academy of Sciences,China. 2 Institute of Geology and Geophysics,China Earthquake Administration,China.

We model a complex 3D anisotropic structure as an aggregate of arbitrarily shaped blocks or volumes separated by triangulated interfaces,and different anisotropic parameters can be defined in different *** anisotropic media,seismic wave travels in the direction of ray vectors with group velocities throughout a ray trajectory,therefore,group velocities expressed by ray angles is required,but difficult to express in terms of phase *** approximate expression in terms of ray angles is derived for weak transversely isotropic media with a vertical symmetry axis(VTI).We also propose a simple iterative process to calculate ray angles in terms of the Snell’s law still valid for phase velocities and phase *** of shooting angles is crucial in implementing 3D shooting ray-tracing,and we suggest to use the sub-triangle shooting method to update the shooting angles to enhance the computing *** tests demonstrate that a blocky model can be a good description of complex 3D VTI media and the sub-triangle shooting ray-tracing is very effective to implement for kinematics two-point ray-tracing.

关键词： phase velocity group velocity Snell’s law ray-tracing.

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农药学学报 2018年第4期20卷 425-438页

作者：王安佳张开心梅向东高玉林张涛折冬梅宁君中国农业科学院植物保护研究所北京100193 中国农业科学院棉花研究所河南安阳455000

昆虫性信息素及其类似物在有害生物综合治理中起到了越来越重要的作用,如可以对目标昆虫进行监测、诱捕和迷向等。干扰昆虫行为是一种环境友好型的植物保护策略,近年来已在害虫防治领域广泛使用。干扰昆虫行为的机理一直是科学家研究的... 详细信息

昆虫性信息素及其类似物在有害生物综合治理中起到了越来越重要的作用,如可以对目标昆虫进行监测、诱捕和迷向等。干扰昆虫行为是一种环境友好型的植物保护策略,近年来已在害虫防治领域广泛使用。干扰昆虫行为的机理一直是科学家研究的主要方向,明确其机理能使之得到更有效合理的应用。本文主要对昆虫性信息素及其类似物干扰昆虫行为的机理,以及缓释材料、施用剂量及密度、与其他挥发性物质在田间混合应用等方面的研究进展进行简要综述。

关键词：昆虫性信息素性信息素类似物干扰交配化学通讯应用

A Federated Learning Framework with Blockchain-Based Auditable Participant Selection

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Computers, Materials & Continua 2024年第6期79卷 5125-5142页

作者： Huang Zeng Mingtian zhang Tengfei Liu anjia Yang College of Cyber Security Jinan UniversityGuangzhou510632China

Federated learning is an important distributed model training technique in Internet of Things(IoT),in which participant selection is a key component that plays a role in improving training efficiency and model *** module enables a central server to select a subset of participants to performmodel training based on data and device *** doing so,selected participants are rewarded and actively perform model training,while participants that are detrimental to training efficiency and model accuracy are ***,in practice,participants may suspect that the central server may have miscalculated and thus not made the selection *** lack of trustworthiness problem,which can demotivate participants,has received little *** problem that has received little attention is the leakage of participants’private information during the selection *** will therefore propose a federated learning framework with auditable participant *** supports smart contracts in selecting a set of suitable participants based on their training loss without compromising the *** the possibility of malicious campaigning and impersonation of participants,the framework employs commitment schemes and zero-knowledge proofs to counteract these malicious ***,we analyze the security of the framework and conduct a series of experiments to demonstrate that the framework can effectively improve the efficiency of federated learning.

关键词： Federated learning internet of things participant selection blockchain auditability privacy

基于线性尼龙共混改性的半芳香尼龙复合材料性能研究

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当代化工研究 2024年第18期 83-85页

作者：张军王楠张安家方略周来雷昌桓许培俊海军装备部陕西710000 重庆长安工业(集团)有限责任公司重庆401120 长安大学材料科学与工程学院陕西710018

聚对苯二甲酰癸二胺(PA10T)是一种新型的半芳香族尼龙材料,具有良好的物理机械性能和耐热性能,但加工性和韧性较差。通过与含量不同的聚癸二酰己二胺PA610共混能够有效改善其加工流动性,并且采用一定量的聚烯烃弹性体还能进一步对PA10T... 详细信息

聚对苯二甲酰癸二胺(PA10T)是一种新型的半芳香族尼龙材料,具有良好的物理机械性能和耐热性能,但加工性和韧性较差。通过与含量不同的聚癸二酰己二胺PA610共混能够有效改善其加工流动性,并且采用一定量的聚烯烃弹性体还能进一步对PA10T起到良好的增韧改性作用。结果表明,采用质量比为70:30的PA10T与PA610共混,能够使其短纤维增强,复合材料注塑产品获得良好的力学性能、耐冲击性能、较低的吸水性和热膨胀系数,更加适合用于制造需要在高温条件下使用的抗冲击聚合物基复合材料制品。

关键词：半芳香尼龙复合材料马来酸酐接枝聚烯烃弹性体增韧改性

Preoperative Prediction of Lymph Node Metastasis in Colorectal Cancer with Deep Learning

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Biomedical Engineering Frontiers 2022年第1期3卷 93-104页

作者： Hailing Liu Yu Zhao Fan Yang Xiaoying Lou Feng Wu Hang Li Xiaohan Xing Tingying Peng Bjoern Menze Junzhou Huang Shujun zhang anjia Han Jianhua Yao Xinjuan Fan Department of Pathology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510655China AI Lab TencentShenzhen 518057China Department of Computer Science Technical University of MunichMunich 85748Germany Department of Computer Science Xiamen UniversityXiamen 361005China Department of Electronic Engineering The Chinese University of Hong KongHong Kong 999077China Institute of Computational Biology Helmholtz Zentrum MünchenNeuherberg 85764Germany Helmholtz AI Helmholtz Zentrum MünchenNeuherberg 85764Germany Department of Quantitative Biomedicine University of ZurichZurich 8091Switzerland Department of Pathology The Fourth Hospital of Harbin Medical UniversityHarbin 150001China Department of Pathology The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China

*** develop an artificial intelligence method predicting lymph node metastasis(LNM)for patients with colorectal cancer(CRC).Impact Statement.A novel interpretable multimodal AI-based method to predict LNM for CRC patients by integrating information of pathological images and serum tumor-specific *** diagnosis of LNM is essential in treatment planning for CRC *** radiology imaging and genomic tests approaches are either unreliable or too ***.A total of 1338 patients were recruited,where 1128 patients from one centre were included as the discovery cohort and 210 patients from other two centres were involved as the external validation *** developed a Multimodal Multiple Instance Learning(MMIL)model to learn latent features from pathological images and then jointly integrated the clinical biomarker features for predicting LNM *** heatmaps of the obtained MMIL model were generated for model *** MMIL model outperformed preoperative radiology-imaging diagnosis and yielded high area under the curve(AUCs)of 0.926,0.878,0.809,and 0.857 for patients with stage T1,T2,T3,and T4 CRC,on the discovery *** the external cohort,it obtained AUCs of 0.855,0.832,0.691,and 0.792,respectively(T1-T4),which indicates its prediction accuracy and potential adaptability among multiple *** MMIL model showed the potential in the early diagnosis of LNM by referring to pathological images and tumor-specific biomarkers,which is easily accessed in different *** revealed the histomorphologic features determining the LNM prediction indicating the model ability to learn informative latent features.

关键词： diagnosis centre latent