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应用保辛Stereo-modeling方法的振幅补偿逆时偏移成像

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石油地球物理勘探 2024年第5期59卷 1037-1047页

作者：李静爽张向佳贺茜君黄雪源中国矿业大学(北京)理学院北京100083 吉林大学地球探测科学与技术学院吉林长春130026 北京工商大学数学与统计学院北京100048

地震波数值模拟的精度很大程度上决定了逆时偏移结果的分辨率,文中采用保辛近似解析离散化方法,在Birkhoffian系统下求解黏滞声波方程,并进行振幅补偿的逆时偏移(RTM)。首先,将黏滞声波方程构造成一个Birkhoffian系统,对于该系统采用二... 详细信息

地震波数值模拟的精度很大程度上决定了逆时偏移结果的分辨率,文中采用保辛近似解析离散化方法,在Birkhoffian系统下求解黏滞声波方程,并进行振幅补偿的逆时偏移(RTM)。首先,将黏滞声波方程构造成一个Birkhoffian系统,对于该系统采用二阶保辛Runge-Kutta法进行时间推进,分别采用Stereo-modeling法(STEM)和传统有限差分法进行空间算子离散,相应得到SSM(Symplectic Stereo-modeling Method)和CSM(Conventional Symplectic Method)两种方法。之后,对SSM和CSM进行一系列数值性质分析,包括数值频散分析、与解析解比较、效率对比、稳定性测试等。结果显示,SSM的最大数值频散误差约为9%,而CSM约为26%;SSM的计算效率高且长时计算稳定,计算效率约为CSM的两倍。最后,应用三个模型进行了正演数值模拟和逆时偏移试验。对于衰减数据,与声波RTM相比,黏滞声波RTM成像振幅更高,能获得与无衰减数据声波RTM相近的成像振幅。对于油气藏模型,SSM比CSM的成像精度更高、数值频散更小。

关键词：黏滞声波方程振幅补偿保辛方法逆时偏移数值频散

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毛泽东历史人物评价标准及其对马克思主义史学发展的贡献

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毛泽东思想研究 2024年第1期 108-118页

作者：李杨黄学渊江西师范大学马克思主义学院江西师范大学江西南昌330022

毛泽东对历史人物的评价经历了一个从传统史学研究者到接受马克思主义唯物史观的转变。延安时期毛泽东对历史人物的评价日趋成熟,能够科学地运用唯物史观并结合中国问题来分析历史人物,以此达到推动中国革命进程的目的。新中国成立后,... 详细信息

毛泽东对历史人物的评价经历了一个从传统史学研究者到接受马克思主义唯物史观的转变。延安时期毛泽东对历史人物的评价日趋成熟,能够科学地运用唯物史观并结合中国问题来分析历史人物,以此达到推动中国革命进程的目的。新中国成立后,毛泽东对历史人物的评价服务于社会主义建设。毛泽东关于历史人物评价标准的发展与创新,不仅对毛泽东史学思想,更对毛泽东思想,甚至对20世纪中国马克思主义史学话语体系的形成都具有重要的推动作用。在毛泽东的影响下,20世纪中国的马克思主义史学快速发展,构建出以人民群众为历史主体的体现中国风格、中国气派、中国特色的话语体系。

关键词：毛泽东唯物史观历史人物评价马克思主义史学

Quasi-waveform seismic tomography of crustal structures in the capital circle region of China

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Science China Earth Sciences 2021年第1期64卷 110-126页

作者： xueyuan huang Dinghui YANG Ping TONG Yuan GAO Yutao SHI Hao WU Department of Applied Statistics School of Mathematics and StatisticsBeijing Technology and Business UniversityBeijing 100048China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Division of Mathematical Sciences School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Asian School of the Environment Nanyang Technological UniversitySingapore 637371Singapore Institute of Earthquake Science China Earthquake AdministrationBeijing 100036China

Seismic tomography is one of the main tools to explore the interior of the *** this study,the quasi-waveform seismic tomographic method is used for the first time to reveal the crustal structures in the capital region of China.3-D highresolution V_P,V_S and the Poisson’s ratio models are generated by inverting 29839 direct P-and 29972 direct S-wave traveltimes selected from 3231 local *** results reveal strong crustal *** velocity anomalies at shallow depths are well consistent with surface geologic *** relatively low-velocity anomaly layer in the middle crust may be the result of multiple phases of tectonic *** generally occurred on the boundaries of high-and low-velocity and Poisson’s ratio *** are obvious low-velocity anomalies below the hypocenters of the Tangshan earthquake and the historical Sanhe-Pinggu earthquake,implying the existence of *** similar velocity structures around the hypocenters of the two earthquakes indicate that the occurrences of the two earthquakes may be related to the same *** highresolution velocity models provide important observational constraints on the small-scale heterogeneities and dynamic mechanism of the crust in the capital region of China.

关键词： Quasi-waveform inversion Capital circle region Seismic tomography Crustal velocity structure Heterogeneity

A New Earthquake Location Method Based on the Waveform Inversion

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Communications in Computational Physics 2018年第1期23卷 118-141页

作者： Hao Wu Jing Chen xueyuan huang Dinghui Yang Department ofMathematical Sciences TsinghuaUniversityBeijing 100084China Department of Mathematics School of ScienceBeijing Technology and Business UniversityBeijing 100048China

In this paper,a new earthquake location method based on the waveform inversion is *** is known to all,the waveform misfit function under the L2 measure is suffering from the cycle skipping *** leads to a very small convergence domain of the conventional waveform based earthquake location *** present study,by introducing and solving two simple sub-optimization problems,we greatly expand the convergence domain of the waveform based earthquake location *** to a large number of numerical experiments,the new method expands the range of convergence by several tens of *** allows us to locate the earthquake accurately even from some relatively bad initial values.

关键词： Computational seismology inverse theory waveforminversion earthquake location

Regional landscape transformation and sustainability of the rural homegarden agroforestry system in the Chengdu Plain,China

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Regional Sustainability 2022年第1期3卷 68-81页

作者： ZHOU Lian huang xueyuan ZHAO Chunmei PU Tiancun ZHANG Lei College of Landscape Architecture Sichuan Agricultural UniversityChengdu611130China

Traditional rural homegarden agroforestry system in the Chengdu Plain of China,called“Linpan”in Chinese,integrates the ecological functions of the landscape with human production *** the driving mechanisms of rural landscape changes in the Chengdu Plain is of great significance from stakeholders’*** the Pidu Linpan Farming System(PLFS)in the suburban area of Chengdu(designated as one of China-Nationally Important Agricultural Heritage Systems in 2020)as a case,this study combined remote sensing image analysis,oral history interviews,and focus group interviews to elucidate the driving forces of landscape changes in the *** results show that tourism development,traffic accessibility,economic demand,and agricultural heritage protection measure are the main driving forces promoting the stability and maintenance of the traditional *** contrast,population ageing,land circulation,centralized residence,climate change,and living and recreational need are the forces leading to adverse changes in the traditional *** addition,these driving forces have led to the gradual abandonment of traditional agricultural activities and critical issues related to rural landscape planning and *** current research indicates that infrastructure construction and increased traditional agricultural income are considered as the best practices of local stakeholders,promoting the development of the protected homegardens of heritage sites and tourist ***,we put forward some suggestions to improve and maintain the traditional rural landscape:(1)establishing a benefit-sharing mechanism;(2)establishing a training system with traditional technology and culture;(3)strengthening infrastructure construction;(4)promoting the development of the agricultural industry;(5)improving the cultural quality of farmers;and(6)establishing a management system with legal *** research can provide a basis for the formulation of r

关键词： Sustainability Rural landscape Homegardens Agricultural heritage Social ecosystem Chengdu Plain

An optimal flow rate allocation model of the oilfield treated oil pipeline network

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Petroleum 2024年第1期10卷 93-100页

作者： Hai Li Tianyou Fan Kun Wang xueyuan Long Yu He Meng Wang Wen Cheng Qian huang Huirong huang Weichao Yu PetroChina Southwest Oil & Gasfield Company China Petroleum Planning & Engineering Institute School of Petroleum Engineering Chongqing University of Science and Technology PipeChina Oil & Gas Control Center

Oilfield treated oil pipeline network is the link connecting the upstream oilfields and the downstream refineries. Due to the differences in operating costs and transportation fee between different pipelines and the fluctuation in the demand and sales prices of the treated oil, there is an optimal flow allocation plan for the pipeline network to make the oilfield company obtain the highest social and economic benefit. In this study, a mixed integer nonlinear programming(MINLP) model is developed to determine the optimal flow rate allocation plan of the large-scale and complex treated oil pipeline network, and both the social and economic benefits are considered simultaneously. The optimization objective is the multi-objective which includes the largest user satisfaction and the highest economic benefit. The model constraints include the oilfield production capacity, refinery demand, pipeline transmission capacity,flow, pressure, and temperature of the node and station, and the pipeline hydraulic and thermal calculations. Python 3.7 is utilized for the programming of the off-line calculation procedure and the MINLP model, and GUROBI 9.0.2 is served as the MINLP solver. Moreover, the model is applied to a real treated oil pipeline network located in China, and three optimization scenarios are analyzed. For social benefit,the values of the user satisfaction of each refinery and the total network are 1 before and after optimization for scenarios 1, 2, and 3. For economic benefit, the annual revenue can be increased by 0.227,0.293, and 0.548 billion yuan after the optimization in scenario 1, 2, and 3, respectively.

关键词： Treated oil pipeline network Flow rate allocation Optimal User satisfaction Economic benefit

成都平原传统场镇与林盘居民点的分布特征及其影响因素——以成都郫县为例

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热带地理 2020年第5期40卷 856-867页

作者：黄学渊张蕾周莲四川农业大学风景园林学院成都611130

基于近现代地图与相关地理信息,结合历史文献与实地考察,通过GIS空间分析、核密度估算、欧氏距离、基尼系数等方法,以传统林盘聚落的核心区成都郫县为例,定量揭示了1947、1970、1985、2000与2018年郫县林盘居民点的空间分布特征与场镇... 详细信息

基于近现代地图与相关地理信息,结合历史文献与实地考察,通过GIS空间分析、核密度估算、欧氏距离、基尼系数等方法,以传统林盘聚落的核心区成都郫县为例,定量揭示了1947、1970、1985、2000与2018年郫县林盘居民点的空间分布特征与场镇分布关系的变化情况。结果表明:1)不同时期林盘居民点的分布具有明显的空间差异性,在改革开放前,林盘居民点的分布极易受到政治经济中心的影响,在改革开放后,其具有均质化快速发展的特点,但城镇化的快速推进从根本上改变了林盘居民点的散居特征,其聚集程度明显增高。林盘居民点高密度区始终具有围绕传统场镇及城镇建成区分布的特点。2)传统场镇的市场半径大致为3 km,交通条件是其选址的首要因素,民国时期场镇选址主要受水路交通影响,建国后水路交通为场镇带来的交通便利逐渐被陆路交通所取代。3)传统场镇的分布会随着林盘居民的自组织行为与相关政策的调控而不断趋于均衡状态,但在改革开放之后,场镇由乡村市场驱动的自由放任式发展转变为地方政府驱动下的固定场所。4)林盘居民点具有沿河流水系分布的特点;传统时期林盘居民点与主要道路之间的关联性较低,但当前其具有沿道路分布的特点。

关键词：成都平原传统场镇林盘居民点分布特征郫县

荒野与聚落:20世纪上半叶川西北羌族的景观经营及生态意蕴

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农业考古 2021年第1期 258-265页

作者：周莲黄学渊张蕾四川农业大学风景园林学院

在20世纪上半叶前往川西北羌族地区考察的西方传教士和中国知识分子的视野中,羌族的景观与自然环境间呈现出良好的平衡状态,其传统景观经营具有原生态自然美及时代价值。本文从荒野景观、生产景观以及生活景观三个方面讨论川西北羌族景... 详细信息

在20世纪上半叶前往川西北羌族地区考察的西方传教士和中国知识分子的视野中,羌族的景观与自然环境间呈现出良好的平衡状态,其传统景观经营具有原生态自然美及时代价值。本文从荒野景观、生产景观以及生活景观三个方面讨论川西北羌族景观的历史情况,深入挖掘川西北羌族传统生态文化与景观经营的内涵,以期为当今的生态文明建设和民族特色村寨建设提供一定借鉴。

关键词：荒野聚落川西北地区羌族景观生态

成都平原林盘景观演变的影响因素及利益诉求:基于口述史的质性研究

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Journal of Resources and Ecology 2023年第1期14卷 124-136页

作者：周莲黄学渊张蕾四川农业大学风景园林学院成都611130

林盘是成都平原特有的乡村景观,是指成都平原及丘陵地区农家院落和周边高大乔木、竹林、河流及外围耕地等自然环境有机融合,形成的农村居住环境形态。近年来由于城市化与老龄化的影响,林盘景观发生了很大的改变。从根源上厘清林盘景观... 详细信息

林盘是成都平原特有的乡村景观,是指成都平原及丘陵地区农家院落和周边高大乔木、竹林、河流及外围耕地等自然环境有机融合,形成的农村居住环境形态。近年来由于城市化与老龄化的影响,林盘景观发生了很大的改变。从根源上厘清林盘景观演变的影响因素是提升成都平原乡村景观整治效果的重要途径。通过口述史访谈与扎根理论探究1949-2020年林盘景观形态演变的深层次因素。结果表明:在林盘景观演变过程中,受益人群、物质基础与文化特色是林盘聚落景观变化的前提条件,生产生活需求和政府主导行为是两项最主要的影响因素,景观变化是最终的结果体现。林盘居民的生产生活需求是景观变化的主要内部驱动力,政府主导行为是聚落发展演变的主要外部驱动力。成都平原林盘景观演变的驱动力可以分为3个阶段:(1)1949–1980年,其驱动力特征为政府力与社会力势均力敌;(2)1981–1993年,其驱动力特征为社会力压制政府力;(3)1994年以后,其驱动力特征为政府力与社会力相持。从林盘聚落景观的演变态势来看,传统林盘形态和聚落布局已无法满足乡村社会经济转型时期的新要求,面临着乡村重构与乡村振兴的挑战。在未来的村镇规划和新型居民点的设计中,需要综合考虑不同利益人群的诉求。

关键词：川西林盘乡村聚落景观演变口述史扎根理论