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991.
通过对极地海洋数据的特征及应用需求分析,基于"一种架构支持多类应用"的传统数据库模式已无法满足需求,本文提出采用"多种架构支持多类应用"模式的数据库设计理念,通过研究极地海洋数据分类分层管理体系,开展极地海洋原始数据层、基础数据层、综合数据层、成果数据层的存储管理机制、数据库体系架构设计、数据库模型设计等关键技术研究,开发数据库查询检索功能,满足用户对极地海洋数据的多样化查询检索、空间可视化展示、关联分析等需求,实现极地海洋数据的有效存储、高效应用和开放共享。  相似文献   
992.
Knowledge Sharing and Service is one effective way to eliminate knowledge poverty and promote social development. Existing knowledge sharing and service is mainly provided in some organizations or specific social groups. Besides, a knowledge sharing and service system about geography, natural resources and ecology has not been reported. We proposed a public welfare professional knowledge-sharing and service platform for all members of society in geography, natural resources and ecology. The construction of a knowledge-sharing and service platform is based on five aspects of work: analysis of user requirements, setting standards and drafting policies, aggregating knowledge resources, the technical realization and the maintenance of service. Knowledge resources can be aggregated by using a “two-step” strategy. A knowledge-sharing and service system can be implemented by using “four-tier” structures that are comprised of resources, resource access, application and service, based on the Hadoop-distributed cluster architecture. It has been proven that adhering to the idea of co-building and co-sharing, and using the mechanism of “payment is equal to benefit” can effectively promote the gathering of knowledge resources, and arouse the enthusiasm of all members of society to participate in knowledge sharing and service, to achieve the objective of narrowing the knowledge gap between social groups.  相似文献   
993.
随着当前气象行业的硬件、数据、系统的集约化程度越来越高,气象基础设施资源云平台已经成为省级最重要的两个基础平台之一,为了让省级基础设施资源池在气象行业得到更好的应用,本文对传统虚拟化技术与超融合架构两种不同技术构建的资源池开展架构灵活性、扩展性、技术特点、差异性等方面的对比,重点分析在气象行业场景中的实际应用效果,得出超融合架构在虚拟化存储和安全方面优势明显,为省级基础设施资源池的技术选型提供参考。  相似文献   
994.
Li  Na  Zhang  Jinliang  Shen  Wenlong  Liu  Yang  Liu  Huaishan  Wang  Jinkai  Xie  Jun 《中国海洋大学学报(英文版)》2020,19(2):320-330
The restoration of the denudation thickness is the basis for quantitatively analyzing the basin burial history,thermal evolution history and hydrocarbon accumulation conditions.The well data is not sufficient to do this in the southern Lishui Sag with only 5 wells,so the new,high-quality three-dimensional(3D)seismic data is essential.The methods employed to determine the eroded thicknesses of key unconformities in the study area are the mudstone acoustic time difference(AC)method,vitrinite reflectance(Ro%)method and stratigraphic trend comparison method.On the basis of the structural evolution,the restoration of the paleogeomorphology is carried out.The results show that the Wenzhou formation(E2 w)in the entire study area has been all denuded.The denudation thickness is in the range of 0–550 m,and decreases gradually from west,thicker than 200 m,to east.The erosion of the upper Lingfeng formation(E1l)are mainly occurred in the N-P-1 structural trap(N-P-1),the N-P-2 structural trap(N-P-2)and the N-P-3 structural trap(N-P-3).Among them,the eroded area in N-P-1(near well S-1)and N-P-2 is 200–230 km^2,and the denudation thickness is 0–600 m,which increases from south to north,even up to 200–400 m in the region around well S-1.In N-P-3,the extent of denudation is 30–50 km^2,and the denudation thickness is 0–400 m.In the early stage of the upper E1 l,one north-south strike slip fault began to develop in the southern study area.Affected by this fault,the southern Lingfeng bulge was offset,forming a gorge,and the eastern and western sides of the concave belt connected to each other.On the basis of the paleo-geomorphological characteristics,it is shown that the sedimentary center of the west subsag began to migrate to the south.  相似文献   
995.
Facilitating linkage of climate policies through the Paris outcome   总被引:1,自引:1,他引:0  
The Durban Platform for Enhanced Action negotiations are likely to lead to a Paris outcome that embodies a hybrid climate policy architecture, combining top-down elements, such as for monitoring, reporting, and verification, with bottom-up elements, including ‘Intended Nationally Determined Contributions’ from participating countries, detailing plans to reduce emissions, based on national circumstances. For such a system to be cost-effective – and thus more likely to embody greater ambition – a key feature will be linkages among regional, national, and sub-national climate policies. By linkage, we mean formal recognition by a mitigation programme in one jurisdiction of emission reductions undertaken in another jurisdiction for the purposes of complying with the first jurisdiction's requirements. The Paris outcome could play at least four different roles with respect to linkage of heterogeneous policy instruments. First, it could discourage linkage, either by not allowing countries to count international transfers toward their mitigation contributions, or by limiting the number or types of transferred units that can be counted for compliance purposes. Second, it could be silent on the topic of linkage, creating legal and regulatory uncertainty about whether international transfers are allowed. Third, it could expressly authorize linkage but not provide any further details about how linkage should occur, leaving it to future United Nations Framework Convention on Climate Change negotiating sessions to work out the details or to national governments to develop bilateral or multilateral linkage arrangements. Finally, the Paris outcome could establish institutional arrangements and rules that facilitate and promote linkage. We examine how a future international policy architecture could help facilitate the growth and operation of a robust system of international linkages. Several design elements merit serious consideration for inclusion in the Paris outcome, either in the core agreement or by establishing a process for subsequent international elaboration. At the same time, including detailed linkage rules in the core agreement is not desirable because this could make it difficult for rules to evolve in light of experience.

Policy relevance

These findings have implications for the efficient and effective design of an international climate policy architecture by detailing the role that linkage can play in supporting heterogeneous climate policies at the regional, national, and sub-national levels.  相似文献   

996.
The last ten years have seen the growth of linkages between many of the world's cap-and-trade systems for GHGs, both directly between systems, and indirectly via connections to credit systems such as the Clean Development Mechanism. If nations have tried to act in their own self-interest, this proliferation of linkages implies that for many nations, the expected benefits of linkage outweighed expected costs. In this article, we draw on the past decade of experience with carbon markets to examine why systems have demonstrated this revealed preference for linking. Linkage is a multi-faceted policy decision that can be used by political jurisdictions to achieve a variety of objectives, and we find qualitative evidence that many economic, political, and strategic factors – ranging from geographic proximity to integrity of emissions reductions – influence the decision to link. We also identify some potentially important effects of linkage, such as loss of control over domestic carbon policies, which do not appear to have deterred real-world decisions to link.

Policy relevance

These findings have implications for the future role that decentralized linkages may play in international climate policy architecture. The Kyoto Protocol has entered what is probably its final commitment period, covering only a small fraction of global GHG emissions. Under the Durban Platform for Enhanced Action, negotiators may now gravitate toward a hybrid system, combining top-down elements for establishing targets with bottom-up elements of pledge-and-review tied to national policies and actions. The incentives for linking these national policies are likely to continue to produce direct connections among regional, national, and sub-national cap-and-trade systems. The growing network of decentralized, direct linkages among these systems may turn out to be a key part of a future hybrid climate policy architecture.  相似文献   

997.
The Early Miocene was a period of active rifting and carbonate platform development in the Midyan Peninsula, NW Saudi Arabia. However, there is no published literature available dealing with the detailed characterization of the different carbonate platforms in this study area. Therefore, this study aims to present new stratigraphic architectural models that illustrate the formation of different carbonate platforms in the region and the forcing mechanisms that likely drove their formation. This study identified the following features formed during active rifting: a) a Late Aquitanian (N4) fault-block hangingwall dipslope carbonate ramp, b) a Late Burdigalian (N7-N8) isolated normal fault-controlled carbonate platform with associated slope deposits, and c) a Late Burdigalian (N7-N8) attached fault-bounded platform with reef buildups, rimmed shelf developed on a footwall fault-tip within a basin margin structural relay zone that formed coinciding with the second stage of rifting. Variations in cyclicity have been observed within the internal stratigraphic architecture of each platform and also between platforms. High-resolution sequence stratigraphic analysis shows to be parasequences the smallest depositional packages (metre-scale cycles) within the platforms. The hangingwall dipslope carbonate ramp and the attached platform demonstrate aggradational-progradational parasequence stacking patterns. These locations appear to have been more sensitive to eustatic cyclicities, despite the active tectonic setting. The isolated, fault-controlled carbonate platform reveals disorganized stratal geometries in both platform-top and slope facies, suggesting a more complex interplay of rates of tectonic uplift and subsidence, variation in carbonate productivity, and resedimentation of carbonates, such that any sea-level cyclicity is obscure. This study explores the interplay between different forcing mechanisms in the evolution of carbonate platforms in active extensional tectonic regions. Characterization of detailed parasequence-scale internal architecture allows the spatial variation in syn-depositional relative base-level changes to be inferred and is critical for understanding the development of rift basin carbonate platforms. Such concepts may be useful for the prediction of subsurface facies relationships beyond interwell areas in hydrocarbon exploration and reservoir modeling activities.  相似文献   
998.
Switched sequence stratigraphic architectural units were developed in the Eocene Wenchang Formation stratigraphic section of the Pearl River Mouth Basin (PRMB), northern South China Sea. Utilizing a high-quality 3D seismic data set, well logs and restored paleogeomorphology, the architecture and genesis of switched sequence stratigraphic units have been systematically investigated. The Wenchang Formation, a second-order sequence, can be subdivided into seven third-order sequences (from base to top: SQ1, SQ2, SQ3, SQ4, SQ5, SQ6, and SQ7). The sequence stratigraphic architecture of the Wenchang Formation is characterized by continuous lateral stacking patterns from sequences SQ1 to SQ7. Sequences SQ1–SQ4 mainly developed in the HZ26 sag, whereas sequences SQ5–SQ7 mainly developed in the XJ24 sag. The depositional centres of the Wenchang Formation appear to have migrated from the HZ26 sag to the XJ24 sag-along the northwest direction from sequences SQ1 to SQ7. Multiple tectonic activation episodes or alternating tectonic subsidence of the HZ26 and XJ24 sags resulted in the distinctive geomorphological features that effected the development of the switched sequence stratigraphic architecture in the study area. The switched sequence stratigraphic architecture presented in this study may provide new insights into a better understanding of sequence stratigraphic stacking patterns in continental lacustrine rift basins.  相似文献   
999.
Understanding fault zone permeability and its spatial distribution allows the assessment of fluid-migration leading to precipitation of hydrothermal minerals. This work is aimed at unraveling the conditions and distribution of fluid transport properties in fault zones based on hydrothermally filled microfractures, which reflect the ‘‘frozen-in’’ instantaneous advective hydrothermal activity and record palaeopermeability conditions of the fault-fracture system. We studied the Jorgillo Fault, an exposed 20 km long, left-lateral strike-slip fault, which juxtaposes Jurassic gabbro against metadiorite belonging to the Atacama Fault System in northern Chile. Tracings of microfracture networks of 19 oriented thin sections from a 400 m long transect across the main fault trace was carried out to estimate the hydraulic properties of the low-strain fault damagezone, adjacent to the high-strain fault core, by assuming penny-shaped microfractures of constant radius and aperture within an anisotropic fracture system. Palaeopermeability values of 9.1*10−11 to 3.2*10−13 m2 in the gabbro and of 5.0*10−10 to 1.2*10−13 m2 in the metadiorite were determined, both decreasing perpendicularly away from the fault core. Fracture porosity values range from 40.00% to 0.28%. The Jorgillo Fault has acted as a left-lateral dilational fault-bend, generating large-scale dilation sites north of the JF during co-seismic activity.  相似文献   
1000.
黄明  张建广  付昕乐  杨芳  郭明 《测绘科学》2016,41(5):111-115,172
针对大规模古建筑三维模型场景渲染效率低的问题,该文提出了一种基于图像处理单元(GPU)的古建筑构件快速绘制的方法:根据复杂古建筑可分解为若干建筑构件的构造特点,把构件作为建模与绘制单元,以具有可编程的DirectX 11作为三维图形引擎,通过GPU物理层的曲面细分技术,实现旋转体建筑构件的精细表达;利用实例化技术,通过一次性创建构件几何缓存,实现大规模三维场景中重复建筑对象的高速绘制。实验结果表明:对于复杂古建筑物的大数据绘制,该方法与传统的CPU渲染方法相比,在渲染速度、可视化效果、大数据承载能力方面都具有显著的优势。  相似文献   
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