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基于科教融合的地震波数值模拟综合实验设计

科技风 2024年第16期 42-44页

作者：武晔顾观文万永革孙守才防灾科技学院地球科学学院河北三河065201 河北省地震动力学重点实验室河北三河065201 廊坊市地球探测与信息技术重点实验室河北三河065201

将地震数值模拟科学研究转化为地球物理学综合实验,对比研究低速层和水层地质模型情况下地震响应特征的差异。通过“引导—启发—设计—指导”逐层递进式实验教学方法,引导学生大胆提出科学问题,鼓励学生自主设计模型加以对比,并得出结... 详细信息

将地震数值模拟科学研究转化为地球物理学综合实验,对比研究低速层和水层地质模型情况下地震响应特征的差异。通过“引导—启发—设计—指导”逐层递进式实验教学方法,引导学生大胆提出科学问题,鼓励学生自主设计模型加以对比,并得出结论。教学实践表明,在验证性实验的基础上,开设“科教融合”综合实验,有助于培养学生的科学创新思维,有利于提高学生的自主学习能力和分析解决问题能力,为后续开展毕业设计和科研工作奠定良好基础。

关键词：科教融合综合实验数值模拟

Evidence for wildfire in the Meishan section and implications for Permian—Triassic events

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Evidence for wildfire in the Meishan section and implication...

滇—黔地球化学边界似基韦诺(Kew eenaw)型铜矿中有机质与成矿条件研究

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Wenjie Shen~(a,c),yongge sun~(b,c,*),Yangting Lin~a,Dehan Liu~c,Pingxia Chai~c a Key Laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing 100029,People’s Republic of China b Department of Earth Science,Zhejiang University,Hangzhou 310027,People’s Republic of China c State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences, Guangzhou 510640,People’s Republic of China

Polynuclear aromatic hydrocarbons(PAHs) and black carbon(BC) in sediments are powerful tools in the identification of the combustion process throughout geologic *** this study,combustion-derived PAHs and BC were carefully investigated in sediments from the Global Stratotype Section and Point of the Permian-Trias sic(P/Tr) boundary in Meishan, *** analyses of combustion-derived PAHs and BC demonstrate anomalously high concentrations in the boundary event beds that coincide with the mass extinction *** prevalence of parent polynuclear aromatics(e.g., phenanthrene) in PAHs,together with non-metric multidimensional scaling analysis,confirms that the PAHs are mainly derived from vegetation burning instead of having a coal and/or oil *** detected in sediment occurs in various forms from large irregular charcoal particles to fine aciniform soot,with an equivalent reflectance of up to 3.5%.The results strongly suggest that a wildfire occurred during the P/Tr boundary,which served as one of the possible triggers of mass extinction on *** wildfire occurrence indicates that the O concentration of the atmosphere during(or before) the P/Tr mass extinction was probably >17%.The temporal coincidence of the mass extinction with intensive volcanic eruption,marine anoxia and wildfire events in the region of the Meishan section provides new insight into the mechanisms of the P/Tr biotic crisis. Our results show that wildfires could have played an important role in the collapse of the ecosystem in the Meishan P/Tr events.

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地质论评 2006年第4期52卷 477-485,i0002-i0003页

作者：刘德汉孙永革徐世平朱炳泉陈广浩柴平霞胡耀国常向阳中国科学院广州地球化学研究所有机地球化学国家重点实验室 510640 中国科学院广州地球化学研究所元素与同位素地球化学重点实验室 510640 中国科学院广州地球化学研究所边缘海地质重点实验室 510640 中国科学院广州土壤研究所 510650 广州大学环境科学与工程学院 510405

用有机岩石学和有机地球化学方法研究了铜矿中有机质的类型、特征及其与自然铜矿化的关系。观测结果表明:矿床中有机质的类型比较复杂,有峨眉山玄武岩晚期火山喷发间歇沉积的腐殖型有机质转变的镜质组、丝质组和由腐泥型有机质成因的充... 详细信息

用有机岩石学和有机地球化学方法研究了铜矿中有机质的类型、特征及其与自然铜矿化的关系。观测结果表明:矿床中有机质的类型比较复杂,有峨眉山玄武岩晚期火山喷发间歇沉积的腐殖型有机质转变的镜质组、丝质组和由腐泥型有机质成因的充填状沥青。铜矿区原生沉积有机质经受的热演化程度达到VRo1.6%～1.9%,远比矿区外围VRo1.08%～1.35%高,说明矿区受热程度高。后期进入的充填沥青热演化程度为ERo=1.32%～1.56%,略比原生沉积有机质低。镜质体和炭化木的总碳同位素介于-21.29‰～-22.5‰之间,充填沥青总碳同位素介于-32.2‰～-33.14‰之间,两类有机质的碳同位素组成差别很大。充填沥青生物标志化合物组合表现为:高三环萜化合物、高伽玛蜡烷、C27-C28-C29甾烷均势分布、丰富四甲基甾烷等,反映出低等水生生源输入特征,综合区域地质背景资料,初步推测其可能来源于古生代海相沉积有机质(泥盆系或下二叠统源岩)。流体包裹体组成的激光拉曼测定结果表明,流体中CH4含量较高,表明成矿体系富含甲烷,有利于氧化铜还原为自然铜的反应。据矿区蚀变矿物组合与有机的热演化程度,以及矿区脉石矿物的流体包裹体均一温度测定结果,玄武岩中的铜具有早期高温分异富集特征,但是大量自然铜是在晚期温度、压力不太高的流体中受多种有机质还原作用形成的。

关键词：自然铜矿床固体沥青镜质体流体包裹体碳同位素生物标志化合物

A discussion on the upper limit of maturity for gas generation by marine kerogens and the utmost of gas generative potential:Taking the study on the Tarim Basin as an example

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Science Bulletin 2007年第S1期 125-132页

作者： CHEN JianPing1,2, ZHAO WenZhi1, XIAO ZhongYao3, ZHANG ShuiChang1,2, DENG ChunPing1,2, sun yongge4 & WANG ZhaoMing3 1 Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China 2 Key Lab of Petroleum Geochemistry, CNPC, Beijing 100083, China 3 Research Institute of Petroleum Exploration & Development, Tarim Oilfield Company, PetroChina, Korla 841000, China 4 State Key Lab of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

The experimental data yielded by Rock-Eval pyrolysis, kerogen atomic H/C, Py-GC and gold-tube sealing thermal simulation on the marine Cambrian-Ordovician source rock from the Tarim Basin revealed that the upper limit of maturity for natural gas generation or the "deadline of gas generation" for marine types I and II kerogens is equal to 3.0% of vitrinite reflectance (Ro); while the "deadline of gas generation" for type III kerogens typically like coals is as high as 10% Ro. Thus, different organic matter has obviously different utmost maturities for gas generation. The mass-balance calculation by kerogen elements showed that when Ro>1.5%, the utmost amount of gas generation for the marine type II kerogen is less than 185 m3/t TOC, accounting for less than 30% of its total hydrocarbon generative potential; when Ro>2.0%, it becomes 110 m3/t TOC, less than 20% of the total hydrocarbon generative potential. The amount of the gas generative potential obtained by Rock-Eval is only around one tenth of the calculated value by the mass balance of kerogen elements at the same thermal evolutionary stage, while those by Py-GC and gold-tube sealing simulation are intervenient between the above two. The utmost of gas generative potential at the over 1.3% Ro stage is around 60―90 m3/t TOC, therefore, the amount of gas generation obtained by Rock-Eval is the minimum of gas generative potential, while that by the mass-balance calculation of kerogen elements is the maximum that the actual amount of gas generation should not exceed.

关键词： marine source rock kerogen maturity natural gas deadline of gas generation utmost of gas generative potential

Stationary response of van der Pol oscillator with two kinds of fractional derivatives under Gaussian white noise excitation

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Stationary response of van der Pol oscillator with two kinds...

结合PCANet与线性判别分析的视网膜光学相干断层扫描图像分类

中国力学大会-2015

作者： Yang yongge Xu Wei Gu Xudong sun Yahui Department of Applied Mathematics Northwestern Polytechnical University Department of Engineering Mechanics Northwestern Polytechnical University State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University

This paper investigates the stochastic response of van der Pol oscillator with two kinds of fractional derivatives under Gaussian white noise *** numerical results not only demonstrate the accuracy of the proposed approach but also show that the fractional order the fractional coefficient and the intensity of Gaussian white noise play important roles in the re-

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中国图象图形学报 2019年第1期24卷 115-123页

作者：丁思静孙中阳孙延奎王永革清华大学计算机科学与技术系北京100084 北京航空航天大学数学与系统科学学院北京100191 广东省大数据分析与处理重点实验室广州510006

目的主成分分析网络(PCANet)能提取图像的纹理特征,线性判别分析(LDA)提取的特征有类别区分性。本文结合这两种方法的优点,提出一种带线性判别分析的主成分分析网络(PCANet-LDA),用于视网膜光学相干断层扫描(OCT)图像中的老年性黄斑变性... 详细信息

目的主成分分析网络(PCANet)能提取图像的纹理特征,线性判别分析(LDA)提取的特征有类别区分性。本文结合这两种方法的优点,提出一种带线性判别分析的主成分分析网络(PCANet-LDA),用于视网膜光学相干断层扫描(OCT)图像中的老年性黄斑变性(AMD)、糖尿病性黄斑水肿(DME)及正常(NOR)这3类的全自动分类。方法 PCANet-LDA算法是在PCANet的基础上添加了LDA监督层,该层加入了类标签对特征进行监督投影。首先,对OCT视网膜图像进行去噪、二值化及对齐裁剪等一系列预处理,获得感兴趣的视网膜区域;然后,将预处理图像送入一个两层的PCA卷积层,训练PCA滤波器组并提取图像的PCA特征;接着,将PCA特征送入一个非线性输出层,通过二值散列和块直方图等处理,得到图像的特征;之后,将带有类标签的图像特征送入一个LDA监督层,学习LDA矩阵并用其对图像特征进行投影,使特征具有类别区分性;最后,将投影的特征送入线性支持向量机(SVM)中对分类器进行训练和分类。结果实验分别在医院临床数据集和杜克数据集上进行,先对OCT图像预处理进行前后对比实验,然后对PCANet特征提取的有效性进行分析,最后对PCANet算法、Sc SPM算法以及提出的PCANet-LDA3种分类算法的分类效果进行对比实验。在临床数据集上,PCANet-LDA算法的总体分类正确率为97. 20%,高出PCANet算法3. 77%,且略优于Sc SPM算法;在杜克数据集上,PCANet-LDA算法的总体分类正确率为99. 52%,高出PCANet算法1. 64%,略优于Sc SPM算法。结论 PCANet-LDA算法的分类正确率明显高于PCANet,且优于目前用于2D视网膜OCT图像分类的先进的Sc SPM算法。因此,提出的PCANet-LDA算法在视网膜OCT图像的分类上是有效且先进的,可作为视网膜OCT图像分类的基准算法。

关键词：光学相干断层扫描年龄相关性黄斑变性糖尿病性黄斑水肿主成分分析网络线性判别分析图像分类半监督学习

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电源一体化区域灭火物联网光口分站

煤矿安全 2020年第7期51卷 100-103页

作者：孙晓东刘永革煤科集团沈阳研究院有限公司辽宁抚顺113122 煤矿安全技术国家重点实验室辽宁抚顺113122 沈阳煤炭科学研究所有限公司辽宁沈阳110011 开滦能源化工股份有限公司河北唐山063018

设计一款电源一体化区域灭火物联网光口分站,介绍了系统架构,论述了模拟量信号隔离抗干扰、开关量及通讯隔离电路、电源一体化供电策略、网光口等关键技术。分站以STM32F429为控制核心,结合传感器输出电路及控制策略,实现全隔离、可巡... 详细信息

设计一款电源一体化区域灭火物联网光口分站,介绍了系统架构,论述了模拟量信号隔离抗干扰、开关量及通讯隔离电路、电源一体化供电策略、网光口等关键技术。分站以STM32F429为控制核心,结合传感器输出电路及控制策略,实现全隔离、可巡检物联感知预警且电源、光电口一体化的区域灭火功能,提高了监控系统系统的抗干扰能力。

关键词：监控系统区域灭火物联网 MESH 光口分站

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690镍基合金管材热挤压过程数值模拟

热加工工艺 2010年第23期39卷 110-112,116页

作者：孙海伟范永革易勇西南科技大学材料科学与工程学院四川绵阳621010

运用有限元方法对690镍基合金热挤压过程进行数值模拟,分析了温度、挤压速度、挤压比以及润滑条件对挤压过程影响,分析了坯料内部应力场、应变场及温度场的变化规律。结果表明,影响挤压力的主要因素是变形温度和挤压比,挤压力与挤压比... 详细信息

运用有限元方法对690镍基合金热挤压过程进行数值模拟,分析了温度、挤压速度、挤压比以及润滑条件对挤压过程影响,分析了坯料内部应力场、应变场及温度场的变化规律。结果表明,影响挤压力的主要因素是变形温度和挤压比,挤压力与挤压比的对数之间呈线性关系。由于摩擦的存在,使得管材外表面温度升高而有产生裂纹的倾向。

关键词：热挤压镍基合金数值模拟

Co-seismic Slip Distribution of the 2001 Kokoxili Earthquake Inverted by the GPS Data

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Earthquake Research in China 2005年第4期19卷 420-429页

作者： Wan yongge Shen Zhengkang He Zhende Wang Min Chen Jie Zhang Zusheng Wang Qingliang Gan Weijun Institute of Geology China Earthquake Administration Beijing 100029 China College of Disaster Prevention Techniques CEA Yanjiao East of Beijing 101601 China Institute of Earthquake Prediction China Earthquake Administration Beijing 100036 China Department of Earth and Space Sciences University of California Los Angeles CA 90095-1567 USA First Monitoring Center China Earthquake Administration Tianjin 300180 China Second Monitoring Center CSB Xi＇ an 710054 China

The authors analyze co_seismic displacement field derived from the Global Position System (GPS) observations collected before and after the 2001 Kokoxili earthquake, western China. Using the co_seismic displacement data, and constrained with surface rupture data, they invert co_seismic slip distribution along the seismic fault. Their result shows that the earthquake ruptured the upper crust down to a depth of 13.1～22km (at 70% certainty), with its optimal estimate at 16.5km. A 2～3m left_lateral strike slip is resolved between the sun Lake segment and the west end of the main rupture zone, although surface rupture has not been observed there. The surface rupture of this earthquake is ended at the sun Lake to the west, but left_lateral slip of 1.5～2.0m seems to exist beyond the east end of surface rupture observed from field geology. Seismic moment release estimated using GPS and surface rupture measurement is 6.0×10 20 N·m, which is in good agreement with the result obtained from seismic wave inversion.

关键词： the Kokoxili earthquake Co-seismic slip distribution GPS data Inversion