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461.
大庆长垣西部地区葡萄花油层主要发育水下分流河道和小片席状砂,砂体厚度1~3 m,横向变化快,分布零散,地震储层预测精度受到限制,给油藏评价和开发带来较大风险。为了提高薄窄砂体预测精度,以古龙油田为例,提出了分步逐级井震联合反演方法:以岩石物理响应特征分析为基础,优选反演方法,优化流程参数,不断增加滚动井数,通过5批161口开发井的优选及调整,砂体预测精度不断提高,确保了该油田初步开发方案实施效果,形成了可以推广应用的滚动预测跟踪调整的工作流程。 相似文献
462.
463.
通过梳理南极条约协商会议(ATCM)形成的相关文件,概述了南极特别保护区设立的发展和南极特别保护区管理计划(草案)的编写与批准流程。对已批准设立的67个南极特别保护区进行统计分析发现,目前保护区总面积超过2700平方千米,分别由13个南极条约协商国提请设立,其中,美国、英国、澳大利亚、新西兰、智利等国提出的占绝大多数;1966年和1985年为保护区设立的两个高峰年份。这些保护区主要以动植物、动植物栖息地或者生态系统为保护内容、以科学价值为保护目标。此外,简要地分析保护区建设的现状、问题和未来发展,介绍我国的南极特别保护区申报工作。 相似文献
464.
PAUL F. STARRS 《Geographical review》2009,99(3):323-355
ABSTRACT. Early work by D. W. Meinig delimiting “The Mormon Culture Region” focused on the spread of the Church of Jesus Christ of Latter‐day Saints (lds ) in a core, domain, and sphere scheme that recognized diffusion of a fast‐growing group bent on shifting its station from cultural edge to religious mainstream. Such a changeover from fringe belief to international force lacks any widely circulated rule book. The lds and its followers today extend influence through diverse, distinct pathways: making missionaries a recognizable global force, offering education on church‐controlled university campuses, emanating wholesomeness, entering high‐security federal service, and attaining national political power. But nothing so locks in an lds message as the standard‐plan meetinghouses, in uniform styles, that mark church presence in North America and other continents. This work analyzes that architecture and examines its fit within lds expansion and presentation of self, not just in the Salt Lake City church but even as imitated by outcast outliers. 相似文献
465.
M. ALIPARAST 《国际泥沙研究》2009,24(1):99-107
A numerical model based upon a second-order upwind ceil-center f'mite volume method on unstructured triangular grids is developed for solving shallow water equations. The assumption of a small depth downstream instead of a dry bed situation changes the wave structure and the propagation speed of the front which leads to incorrect results. The use of Harten-Lax-vau Leer (HLL) allows handling of wet/dry treatment. By usage of the HLL approximate Riemann solver, also it make possible to handle discontinuous solutions. As the assumption of a very small depth downstream oftbe dam can change the nature of the dam break flow problem which leads to incorrect results, the HLL approximate Riemann solver is used for the computation of inviscid flux functions, which makes it possible to handle discontinuous solutions. A multidimensional slope-limiting technique is applied to achieve second-order spatial accuracy and to prevent spurious oscillations. To alleviate the problems associated with numerical instabilities due to small water depths near a wet/dry boundary, the friction source terms are treated in a fully implicit way. A third-order Runge-Kutta method is used for the time integration of semi-discrete equations. The developed numerical model has been applied to several test cases as well as to real flows. The tests are tested in two cases: oblique hydraulic jump and experimental dam break in converging-diverging flume. Numerical tests proved the robustness and accuracy of the model. The model has been applied for simulation of dam break analysis of Torogh in Iran. And finally the results have been used in preparing EAP (Emergency Action Plan). 相似文献
466.
Torsional balance as new design criterion for asymmetric structures with energy dissipation devices 总被引:2,自引:0,他引:2
Lateral–torsional coupling in asymmetric‐plan buildings leads to correlated translations and rotations of the building plan, which generate uneven distributions of deformation demand among resisting planes. The deformation demand of a resisting plane depends on the relative magnitude of the plan translation and rotation and on the correlation between the two signals. Thus, small rotations highly correlated with building translation may lead to significantly different deformations of the resisting planes at the building edges. Consequently, the use of supplemental dampers is intended not only to reduce the magnitude of the plan translation and rotation, but also the correlation between these motions. For the sake of simplicity, linear viscous dampers are used in this investigation, which properly located in plan lead to a minimum response of the geometric center, thus achieving the same mean‐square value of the displacements at the building edges. Mathematically, this condition may be understood as creating zero correlation between the translations and rotation at the geometric center of the plan, which represents an uncoupling in the mean‐square sense. Results show that the optimal damper location depends on the static eccentricity and frequency ratio of the bare structure, the total amount of supplemental damping considered, and the frequency content of the excitation. Through a final 6‐story model example, the torsional balance concept is demonstrated to work on multistory buildings subjected to bidirectional ground motions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
467.
Decision support tools in marine spatial planning: Present applications,gaps and future perspectives
《Marine Policy》2017
Evidence-based decision making is an essential process for sustainable, effective, and efficient marine spatial planning (MSP). In that sense, decision support tools (DSTs) could be considered to be the primary assistant of planners. Although there are many DSTs listed in tool databases, most of them are conceptual and not used in real MSP implementation. The main objective of this review is to: (i) characterize and analyse the present use of the DSTs in existing MSP implementation processes around the world, (ii) identify weaknesses and gaps of existing tools, and (iii) propose new functionalities both to improve their feasibility and to promote their application. In total, 34 DSTs have been identified in 28 different MSP initiatives with different levels of complexity, applicability and usage purposes. Main characteristics of the tools were transferred into a DST matrix. It was observed that limited functionality, tool stability, consideration of economic and social decision problems, ease of use, and tool costs could be considered as the main gaps of existing DSTs. Future developments are needed and should be in the direction of the specific need of marine planners and stakeholders. Results revealed that DST developments should consider both spatial and temporal dynamics of the ocean, and new tools should provide multi-functionality and integrity; meanwhile they should be easy to use and freely available. Hence, this research summarised current use, gaps, and expected development trends of DSTs and it concludes that there is still a big potential of DST developments to assist operational MSP processes. 相似文献
468.
469.
长江三峡及邻区构造应力场和震源错动类型的研究 总被引:2,自引:2,他引:0
在文献[3]提出的用计算机确定震源断层面解的基础上,进一步给出了解的置信度。置信度由两个因子组成(C_1,C_2)。其中C_1为初动符号的符合比,C_2为解的不可变动空间与全部空间的比。使用长江三峡及邻区(北纬28°-34°,东经108°-114°)1974年以来的初动观测资料,确定了Ms≥2.1的40次地震的断层面解、该区的区域应力场和分区应力场及平均错动性质。此外还给出了黄陵背斜地区的应力场特征。结果表明,黄陵背斜的地震构造活动具有整体性,构造过程发生在15~20km的深度,张应力轴的方向分布显示以背斜为中心的幅射状态。 相似文献
470.
《The Professional geographer》1985,37(3):357-389
Book Reviewed in this article: Redundant Spaces in Cities and Regions? Studies in Industrial Decline and Social Change . J. Anderson, S. Duncan and R. Hudson. eds. The Social Consequences and Challenges of New Agricultural Technologies . Gigi M. Berardi and Charles C. Geisler, eds. Determinants of Fertility in Developing Countries, Vol. I, Supply and Demand for Children . Rodolfo A. Bultao and Ronald D. Lee, eds. Computer Mapping: Progress in the‘80s . James R. Carter. Washington: Colonial Africa . A. J. Christopher. Geography of the Soviet Union . J. P. Cole. Chicago Mapmakers, Essays on the Rise of the City's Map Trade . Michael P. Conzen, ed. Changes in the Land: Indians, Colonists and the Ecology of New England . William Cronon. Mizner's Florida: American Resort Architecture . Donald W. Curl. Geographical Studies on the Soviet Union: Essays in Honor of Chauncy D. Harris . George Demko and Roland J. Fuchs, eds. Fluvial Hydrology . S. Lawrence Dingman. Pueblo Indian Water Rights: Struggle For a Precious Resource . Charles T. DuMars, Marilyn O'Leary and Albert E. Utton. Women in the Cities of Asia: Migration and Urban Adaptation . James T. Fawcett, Siew-Ean Khoo, and Peter C. Smith, eds. America's National Parks and Their Keepers . Ronald A. Foresta. Neighborhood Revitalization and the Postindustrial City . Dennis E. Gale. China in Canada: A Dialogue on Resources and Development . R. Louis Gentilcore, ed. China: The 80s Era . Norton Ginsburg and Bernard A. Lalor, eds. Boulder, CO: Global Resources: Challenges of Interdependence . Martin I. Glassner, ed. River Networks . Texas: A Geography . Terry G. Jordan with John L. Bean, Jr. and William M. Holmes. The American Frontier: An Archaeological Study of Settlement Pattern and Process . Kenneth E. Lewis. Water Resources, Geography and Law . Olen Paul Matthews. A Field Guide to American Houses . Virginia and Lee McAlester. Population: Patterns, Dynamics, and Prospects . James L. Newman and Gordon E. Matzke. Wood, Brick, and Stone, The North American Settlement Landscape, Vol. 1: Houses . Allen G. Noble. Historical Analysis in Geography . William Norton. The Displaced Worker and Community Response: Case Study of Portsmouth, Scioto County, Ohio . H. Milton Patton and Janet W. Patton. Disaster Management: Warning Response and Community Relocation . Ronald W. Perry and Alvin H. Muskatel. The Anthropology of Space: Explorations into the Natural Philosophy and Semantics of the Navajo . Rik Pinxten, Ingrid van Dooren, and Frank Harvey. What STYLE Is It? A Guide To American Architecture . John C. Poppeliers, S. Allen Chambers, Jr., and Nancy B. Schwartz. Appalachia: A Regional Geography—Land, People and Development . Karl Raitz and Richard Ulack. An Introduction to Urban Geography . John R. Short. Ford, A Village in the West Highlands of Scotland: A Case Study of Repopulation and Social Change in a Small Community . John B. Stephenson. Income and Jobs: USA Diagnosing the Reality . George Sternlieb and James W. Hughes. Weather and Climate of the Antarctic . W. Schwerdtfeger. History and Ecology: Studies of the Grassland, James C. Malin . Robert P. Swierenga, ed. Optimal Control of Spatial Systems . K. C. Tan and R. J. Bennett. Social Science and Revolutions . Stan Taylor. The Global Textile Industry . Brian Toyne, Jeffrey S. Arpan, David A. Ricks, Terence A. Shimp and Andy Barnett. Integrated Water Development: Water Use and Conservation Practice in Western Colorado . James L. Wescoat, Jr. Proceedings of the First International Symposium on Maps and Graphics for the Visually Handicapped . Joseph W. Wiedel, ed. 相似文献