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A PROJECTION METHOD WITH REGULARIZATION FOR THE CAUCHY PROBLEM OF THE HELMHOLTZ EQUATION

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Journal of Computational Mathematics 2012年第2期30卷 157-176页

作者： Yunyun Ma Fuming Ma heping dong School of Mathematics Jilin UniversityChangchun 130012China

This paper is concerned with the reconstruction of the radiation wave field in the exterior of a bounded two- or three-dimensional domain from the knowledge of Cauchy data on a part of the boundary of the aforementioned domain. It is described by the Cauchy problem for the Helmholtz equation. By using the Dirichlet-to-Neumann map, this problem is transformed into an operator equation with compact operator. We rigorously justify the asymptotic behaviors of singular values of the compact operator. Then a projection method with regularization is applied to solve the operator equation, and the convergence of the regularization method is discussed. Finally, several numerical examples are presented to illustrate the approach. The results demonstrate that the algorithm is *** subject classification： 35R25, 35R30, 78A40.

关键词： Helmholtz equation Cauchy Problem Projection method Regularization.

A FINITE ELEMENT METHOD WITH RECTANGULAR PERFECTLY MATCHED LAYERS FOR THE SCATTERING FROM CAVITIES

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Journal of Computational Mathematics 2009年第6期27卷 812-834页

作者： Deyue Zhang Fuming Ma heping dong School of Mathematics Jilin University Changchun 130012 China

We develop a finite element method with rectangular perfectly matched layers （PMLs） for the wave scattering from two-dimensional cavities. The unbounded computational domain is truncated to a bounded one by using of a rectangular perfectly matched layer at the open aperture. The PML parameters such as the thickness of the layer and the fictitious medium property are determined through sharp a posteriori error estimates. Numerical experiments are carried out to illustrate the competitive behavior of the proposed method.

关键词： Cavity Perfectly matched layers Finite element method.

Spatial Distribution and Controlling Factors of Sedimentary Bodies in Jiaozhou Bay and Adjacent Sea Areas, Qingdao

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Journal of Ocean University of China 2011年第2期10卷 106-112页

作者： dong heping LI Guangxue LI shuanglin LI Shaoquan LI Chun College of Marine Geoscienees Ocean University of China Qingdao 266100 P. R. China Key Laboratory of Hydrocarbon Resource and Environmental Geology Qingdao 266071 P. R. China Qingdao Institute of Marine Geology Qingdao 266071 P. R. China

The distributions of thickness of unconsolidated Quaternary sedimentary layers in Jiaozhou Bay and Qingdao offshore area were studied by using 1079-km high-resolution shallow seismic profiles and drilling core data, and the factors controlling the Quaternary evolution were discussed. The results show that such thickness distributions resulted from the coactions of geologic structures and marine hydrodynamic conditions since the Holocene. The geologic structures controlled the slope deposit, proluvial and fluvial fillings since the late Pleistocene. Holocene marine hydrodynamics eroded away sediments at the bay mouth, and tides carried these eroded materials to the sides of the bay mouth and released them there, forming channel-ridge-alternating geomorphic features. During transgressive processes, the sea level rose rapidly, and insufficient sediment supply and tidal actions yielded the relict sediments in the east of Qingdao offshore area.

关键词： sedimentary mass sediment-controlling factor Jiaozhou Bay of Qingdao

Foundation Treatments for Embankments over Highly Compressible Peat in CKE Project

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Journal of Civil Engineering and Architecture 2011年第12期5卷 1138-1141页

作者： Qi Zhang Xiaqiang Qin heping dong Xia Yan China Metallurgical Group Corporation （MCC） CKE Project Office No. 97Awarakotuwa Kerawalapitiya Wattala Sri Lanka China Metallurgical Group Corporation （MCC） No. 777 Pangu Road Baoshan District ShanghaL China

The construction of CKE road embankments is undertaken over soft soils, which include peats, organic soils, clays and sludge. The moisture content of peat is up to 700% and void ratio is up to 11.99. It＇s very easy for the embankments of high moisture content, high void ratio and of the high compression nature to cause too much settlement and loss of stability. Embankment stability during construction and residual settlement of pavement during service period are two major challenges to be faced of the design and construction. This paper outlines the site investigation, laboratory tests and monitoring data in a few selected existing preloading areas, and presents the back-analysis results of the modified secondary compression indices of in-situ soft materials. It is found that the early monitoring data after primary settlement completion are a more reliable approach to estimate the residual settlements within a nominated duration.

关键词： Highly compressible peat study of residual settlement.

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民生关怀:中国宪政改革的现实基础

法律科学（西北政法大学学报） 2009年第3期27卷 33-40页

作者：董和平西北政法大学行政法学院陕西西安710063

中国正处于社会转型的重要历史时期,选择一种符合国情的、合理的、适时的宪政改革路径和步骤至关重要。现阶段中国宪政改革应该以民生关怀作为切入点,围绕解决社会危机事件和众所注目的社会热点问题启动宪政改革,先实施体制内宪政微调,... 详细信息

中国正处于社会转型的重要历史时期,选择一种符合国情的、合理的、适时的宪政改革路径和步骤至关重要。现阶段中国宪政改革应该以民生关怀作为切入点,围绕解决社会危机事件和众所注目的社会热点问题启动宪政改革,先实施体制内宪政微调,弥补立法和制度缺漏,改进相关管理及其运作方式,解决民主宪政操作层面的具体问题,尽可能发挥现有体制民生设计的预期效益。以民生需要基础考虑中国宪政改革,就必须通过推行人民代表的"非行政化"、专职化和完善选举制度强化人民代表大会的民意代表地位和功能,同时强化行宪主体的责任追究和宪法实施的社会监督。

关键词：民生关怀宪政改革路径步骤体制优化

政体选择与国情影响——基于中亚五国政体模式的分析

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法学论坛 2014年第3期29卷 73-78页

作者：董和平青岛大学法学院山东青岛266071

中亚国家的宪法体制正处于一个持续转型时期,移植于西方国家的宪法制度呈现出强势总统、弱势议会、司法独立不足、选举与政党制度流于形式的特点。这既有历史遗存的影响,某种程度上也是社会转型时期的现实政治需要。这些特点及其政治后... 详细信息

中亚国家的宪法体制正处于一个持续转型时期,移植于西方国家的宪法制度呈现出强势总统、弱势议会、司法独立不足、选举与政党制度流于形式的特点。这既有历史遗存的影响,某种程度上也是社会转型时期的现实政治需要。这些特点及其政治后果的存在说明,宪法制度的转型是一个复杂漫长的历史过程,制度借鉴与移植是必要的,但更重要的是宪法制度的建设要结合本国国情,创造特色设计,否则便难以产生民主实效。

关键词：政体中亚五国宪法特点国情选择

An analysis of organic matter sources for surface sediments in the central South Yellow Sea,China:Evidence based on macroelements and n-alkanes

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An analysis of organic matter sources for surface sediments ...

北黄海盆地东部坳陷中生界烃源岩特征及其指示的油气勘探方向

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Shengyin Zhang Shuanglin Li heping dong Qingfang Zhao Xinchuan Lu Ji'an Shi Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources ResearchInstitute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Ministry of Land and Resources Qingdao Institute of Marine Geology

By analyzing the composition of n-alkane and macroelements in the surface sediments of the central South Yellow Sea of China,we evaluated the influencing factors on the distribution of organic *** analysis indicates that the distribution of total organic carbon(TOC)was low in the west and high in the east,and TOC was more related to AlO content than medium diameter(MD).The composition of n-alkanes indicated the organic matter was mainly derived from terrestrial higher *** from herbaceous plants and woody plants were *** comprehensive analysis of the parameters of macroelements and n-alkanes showed the terrestrial organic matter in the central South Yellow Sea was mainly from the input of the modern Yellow River and old Yellow ***,some samples exhibited evident input characteristics from petroleum sources,which changed the original n-alkanes of organic matter in sediments.

关键词： Surface sediment Organic matter Macroelements n-Alkanes South Yellow Sea

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地球科学 2020年第2期45卷 583-601页

作者：蔡来星肖国林董贺平庞玉茂郭兴伟青岛海洋地质研究所山东青岛266071 青岛海洋科学与技术试点国家实验室海洋矿产资源评价与探测技术功能实验室山东青岛266237 山东科技大学地球科学与工程学院山东青岛266590

为了量化表征北黄海盆地东部坳陷中生界主力烃源岩生、排烃特征,综合利用镜质体反射率(Ro)、残余有机碳含量(TOC)、岩石热解、干酪根镜检及饱和烃色谱等资料,在总结研究区烃源岩地化特征的基础上,通过油源对比明确主力烃源岩层并依托盆... 详细信息

为了量化表征北黄海盆地东部坳陷中生界主力烃源岩生、排烃特征,综合利用镜质体反射率(Ro)、残余有机碳含量(TOC)、岩石热解、干酪根镜检及饱和烃色谱等资料,在总结研究区烃源岩地化特征的基础上,通过油源对比明确主力烃源岩层并依托盆地模拟方法量化其生、排烃贡献.结果表明,北黄海盆地东部坳陷中生界的两类原油均来源于区内中侏罗统和上侏罗统两套主力烃源岩层,其中,中侏罗统烃源岩的有机质丰度整体处于"好-最好"级别,上侏罗统烃源岩的有机质丰度则以"中等-好"为主;二者均存在早白垩世末期和早中新世两次生、排烃高峰,但上侏罗统的排烃速率[qe(max)=27.3×106t/Ma]远高于中侏罗统的排烃速率[qe(max)=4.2×106t/Ma],对研究区油气成藏的贡献更大.虽然下白垩统暗色泥岩的生烃潜力有限,但其底部砂岩与紧邻上侏罗统主力烃源岩层构成的"下生上储"式的源储配置关系是区内最重要的勘探目的层,其次为中、上侏罗统内部"自生自储"式的有利成藏组合,同时,中侏罗统下部"上生下储"式的成藏组合也应予以重视.

关键词：烃源岩评价油源对比主力烃源岩勘探方向中生界东部坳陷北黄海盆地油气地质

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BIM机电建模方法研究

建筑经济 2022年第S1期43卷 483-486页

作者：董晓丽关智文董和平北京城市学院北京100083

相比较BIM建筑结构建模,BIM机电模型创建过程中样板文件的设置、机电管道综合排布、协同设计等都比较复杂。通过对子规程设置、管道及管道系统设置、颜色设置等进行较深入地分析,明确创建BIM机电模型样板文件的核心要点,对比分析协同工... 详细信息

相比较BIM建筑结构建模,BIM机电模型创建过程中样板文件的设置、机电管道综合排布、协同设计等都比较复杂。通过对子规程设置、管道及管道系统设置、颜色设置等进行较深入地分析,明确创建BIM机电模型样板文件的核心要点,对比分析协同工作集方式和链接模型方式两种常用的Revit软件协同设计方式的优缺点,梳理管道综合布设原则。

关键词： BIM 机电建模 Revit MEP 协同设计