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用地震反射资料确定速度和深度的方法

石油物探译丛 1989年第3期 28-33页

作者： e.landa 胡中平

在地震资料的处理和解释过程中,确定速度和深度非常重要。我们提出了一种从未叠加的资料中确定速度—深度模型的方法。这种方法可被表示成一个迭代算法,其产生的模型使沿射线追踪旅行时计算的相关值达到最大。在这个模型中各个界面都是... 详细信息

在地震资料的处理和解释过程中,确定速度和深度非常重要。我们提出了一种从未叠加的资料中确定速度—深度模型的方法。这种方法可被表示成一个迭代算法,其产生的模型使沿射线追踪旅行时计算的相关值达到最大。在这个模型中各个界面都是用三次样条函数来表示的,并假设每一层的速度为常数。其反演包括确定各层的速度和样条函数结点的位置。反演是用迭代方法一层一层来实现的;在每次迭代过程中都要计算所研究界面的人工合成传播时间曲线。用人工合成旅行时间形成一个刻划波场主要相关特性的函数。并且假定,当人工合成旅行时曲线与实际同相轴的旅行时曲线吻合时这样函数有最大值。该函数的最大值可以用有效的非线性计算程序得到。该反演算法有不少优越性,如不需要在未叠加资料上进行同相轴拾取,也不要用旅行时双曲线逼近曲线拟合。把这种方法用于人工合成资料和野外资料都已取得成功。

关键词：地震资料反射资料速度深度反演

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相干反演速度估计结果的解释

石油物探译丛 1992年第4期 45-51页

作者： e.landa 解凤英

相干反演速度估算能提供地下的速度/深度宏观模型,这种模型的精度对于象深度偏移和反演之类的成象技术来说是至关重要的.因此,地震解释的可靠性极大地取决于导出的模型精度.模型速度和深度估算结果中的不确定性可利用响应面技术结合Dix... 详细信息

相干反演速度估算能提供地下的速度/深度宏观模型,这种模型的精度对于象深度偏移和反演之类的成象技术来说是至关重要的.因此,地震解释的可靠性极大地取决于导出的模型精度.模型速度和深度估算结果中的不确定性可利用响应面技术结合Dix方程计算.用剥层方案,既考虑了与要研究的某一地层有关的局部误差,也考虑了与上覆层有关的全局误差.合成数据和实际数据的例子说明,相干反演能产生精确的宏观模型.

关键词：相干反演速度响应面解释地震

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地震成像究竟对多少?

石油物探译丛 1999年第4期 29-34页

作者： e.landa 郝敬华边海军河南省濮阳市勘探开发研究院

在利用地震资料进行深度解释的过程中对速度模型的估测是关键的一步,深度成像的质量在很大程度上取决于输入的速度模型,而这一模型本身又依赖于输入的数据、反演算法、所选模型的类型(包括反射界面的数目,界面参数的质量,几何形状,速度... 详细信息

在利用地震资料进行深度解释的过程中对速度模型的估测是关键的一步,深度成像的质量在很大程度上取决于输入的速度模型,而这一模型本身又依赖于输入的数据、反演算法、所选模型的类型(包括反射界面的数目,界面参数的质量,几何形状,速度等等),后者常常是从以前的地质资料和/或对叠加时间剖面的解释中得出的。

关键词：速度模型深度偏移地震成像地震勘探

基于模型的叠加:适于复杂覆盖层的精确的零偏移距剖面的构成方法

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油气藏评价与开发 1994年第4期 78-78页

作者： e.landa

在叠加结果真正反映了零偏移距剖面的前提下,叠后时间剖面的解释可产生正确的地下地质图像。但这种假设在地层倾斜并存在强烈的横向速度变化时是不成立的。本文提出了一种新的零偏移距剖面构成方法,称之为以模型为基础的叠加方法。该方... 详细信息

在叠加结果真正反映了零偏移距剖面的前提下,叠后时间剖面的解释可产生正确的地下地质图像。但这种假设在地层倾斜并存在强烈的横向速度变化时是不成立的。本文提出了一种新的零偏移距剖面构成方法,称之为以模型为基础的叠加方法。该方法实现时不同于常规叠加方法,即并非沿双曲线轨迹叠加,而是沿实际旅行时曲线对共中心点道集中的各道进行叠加。每一共中心点道集的理论曲线通过速度一深

关键词：零偏移距共中心点道集构成方法旅行时基于模型

通过地震折射数据的相干反演确定浅层速度—深度模型

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油气藏评价与开发 1995年第5期 85-85页

作者： e.landa

在地震勘探中,地震折射波有着多种不同的用途。炮点记录上作为初至波的折射波旅行时已用于野外静校正的计算。本文提出一种根据折射波同相轴构制表层模型的新方法。该方法不需要在叠前记录上拾取同相轴,也不需要对波至时间做任何近似。... 详细信息

在地震勘探中,地震折射波有着多种不同的用途。炮点记录上作为初至波的折射波旅行时已用于野外静校正的计算。本文提出一种根据折射波同相轴构制表层模型的新方法。该方法不需要在叠前记录上拾取同相轴,也不需要对波至时间做任何近似。该方法需在折射旅行时时窗内利用炮点道集计算相

关键词：旅行时炮点静校正折射波

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei e Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

FSCIL-eACA: Few-Shot Class-Incremental Learning Network Based on embedding Augmentation and Classifier Adaptation for Image Classification

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Chinese Journal of electronics 2024年第1期33卷 139-152页

作者： Ruru ZHANG Haihong e Meina SONG School of Computer Science Beijing University of Posts and Telecommunications education Department Information Network engineering Research Center Beijing University of Posts and Telecommunications

The ability to learn incrementally is critical to the long-term operation of AI systems. Benefiting from the power of few-shot class-incremental learning(FSCIL), deep learning models can continuously recognize new classes with only a few samples. The difficulty is that limited instances of new classes will lead to overfitting and exacerbate the catastrophic forgetting of the old classes. Most previous works alleviate the above problems by imposing strong constraints on the model structure or parameters, but ignoring embedding network transferability and classifier adaptation(CA), failing to guarantee the efficient utilization of visual features and establishing relationships between old and new classes. In this paper, we propose a simple and novel approach from two perspectives: embedding bias and classifier bias. The method learns an embedding augmented(eA) network with cross-class transfer and class-specific discriminative abilities based on self-supervised learning and modulated attention to alleviate embedding bias. Based on the adaptive incremental classifier learning scheme to realize incremental learning capability,guiding the adaptive update of prototypes and feature embeddings to alleviate classifier bias. We conduct extensive experiments on two popular natural image datasets and two medical datasets. The experiments show that our method is significantly better than the baseline and achieves state-of-the-art results.

关键词： Training Adaptation models Visualization Image recognition Prototypes Self-supervised learning Power capacitors