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101.
当前,风景园林设计行业已成为GIS技术重要的应用领域。笔者通过分析高校风景园林专业GIS的应用需求,依据风景园林专业学生的特点,从教材的选择、授课时间、课程设置内容和考核方式4个方面,探讨有效的风景园林专业GIS课程教学方法。  相似文献   
102.
汤风林  林希强 《现代地质》2000,14(1):100-104
复合土钉支护技术是在土钉支护结构中复合其他土体加固技术的综合支护技术 ,是近年来在城市建筑深基坑支护工程中发展起来的一种具有中国特色的土钉支护技术。通过工程实例讨论了广州地区复合土钉支护工程中使用的基本支护结构、施工技术和工艺流程 ,并在此基础上提出了建议和意见  相似文献   
103.
张正  唐娉  李宏益  冯峥 《遥感学报》2016,20(2):184-196
大数据技术中的一个难点是如何统筹多源异构的数据。在多源数据协同定量遥感产品生产系统中,不同传感器数据的协同使用为生产系统的各个环节都带来了许多的问题,例如异构数据文件的统一表示和调度,繁杂生产流程的统一抽象等。领域驱动设计是一种应对软件核心复杂性的设计方式。领域驱动是指在设计过程中经过不断的迭代,逐渐提炼出一套灵活优雅的领域模型。领域模型专注于分析问题领域本身,发掘重要的业务领域概念,并建立业务领域概念之间的关系。本文在不断实践的基础上提出了一组较成熟的领域模型,该模型用一种统一的方式解决了多源数据协同生产系统中各方面的问题,并显著地降低了系统集成的难度和工作量,且为新数据源的加入预留了灵活性。  相似文献   
104.
The Cretaceous system of the Kuqa depression is a regional scale (second order) depositional sequence defined by parallel unconformities or minor angular unconformities. It can be divided into four third-order sequence sets, eleven third-order sequences and tens of fourth- and fifth-order sequences. It consists generally of a regional depositional cycle from transgression to regression and is composed of three sets of facies associations: alluvial-fluvial, braided river-deltaic and lacustrine-deltaic facies associations. They represent the lowstand, transgressive and highstand facies tracts within the second-order sequence. The tectonic subsidence curve reconstructed by backstripping technique revealed that the Cretaceous Kuqa depression underwent a subsidence history from early accelerated subsidence, middle rapid subsidence and final slower subsidence phases during the Cretaceous time, with the correspondent tectonic subsidence rates being 30-35 m/Ma, 40-45 m/Ma and 5-10 m/Ma obtained from northern foredeep. This is likely attributed to the foreland dynamic process from early thrust flexural subsidence to late stress relaxation and erosion rebound uplift. The entire sedimentary history and the development of the three facies tracts are a response to the basin subsidence process. The slower subsidence foreland gentle slope was a favorable setting for the formation of braided fluvial deltaic systems during the late period of the Cretaceous, which comprise the important sandstone reservoirs in the depression. Sediment records of impermanent marine transgression were discovered in the Cretaceous and the major marine horizons are correctable to the highstands of the global sea level during the period.  相似文献   
105.
The crustal structure of the Dabie orogen was reconstructed by a combined study of U–Pb ages, Hf and O isotope compositions of zircons from granitic gneiss from North Dabie, the largest lithotectonic unit in the orogen. The results were deciphered from metamorphic history to protolith origin with respect to continental subduction and exhumation. Zircon U–Pb dating provides consistent ages of 751 ± 7 Ma for protolith crystallization, and two group ages of 213 ± 4 to 245 ± 17 Ma and 126 ± 4 to 131 ± 36 Ma for regional metamorphism. Majority of zircon Hf isotope analyses displays negative εHf(t) values of − 5.1 to − 2.9 with crust Hf model ages of 1.84 to 1.99 Ga, indicating protolith origin from reworking of middle Paleoproterozoic crust. The remaining analyses exhibit positive εHf(t) values of 5.3 to 14.5 with mantle Hf model ages of 0.74 to 1.11 Ga, suggesting prompt reworking of Late Mesoproterozoic to Early Neoproterozoic juvenile crust. Zircon O isotope analyses yield δ18O values of − 3.26 to 2.79‰, indicating differential involvement of meteoric water in protolith magma by remelting of hydrothermally altered low δ18O rocks. North Dabie shares the same age of Neoproterozoic low δ18O protolith with Central Dabie experiencing the Triassic UHP metamorphism, but it was significantly reworked at Early Cretaceous in association with contemporaneous magma emplacement. The Rodinia breakup at about 750 Ma would lead to not only the reworking of juvenile crust in an active rift zone for bimodal protolith of Central Dabie, but also reworking of ancient crust in an arc-continent collision zone for the North Dabie protolith. The spatial difference in the metamorphic age (Triassic vs. Cretaceous) between the northern and southern parts of North Dabie suggests intra-crustal detachment during the continental subduction. Furthermore, the Dabie orogen would have a three-layer structure prior to the Early Cretaceous magmatism: Central Dabie in the upper, North Dabie in the middle, and the source region of Cretaceous magmas in the lower.  相似文献   
106.
介绍了J2EE架构和多层体系结构的发展,在B/S三层架构的基础上给出了包含应用服务器中间件的多层分布式应用体系结构,并把此体系结构应用于电信氽业的有价卡管理系统项目中。分析了此项同的功能结构和体系结构,采用J2EE开发平台和技术设计实现了由浏览器、Web服务器、应用服务器、数据库服务器组成的多层体系架构。  相似文献   
107.
Multi-stage differential transgression controls sequence architecture and its sedimentary type and distribution during the tectonic evolution of lacustrine rift basin. Combined with the seismic data of the Baxian sag as well as drilling,logging,core and paleontological materials from 800 exploration wells,the study targeted the Members 1 and 3 of the Shahejie Formation to analyze sequence architecture and sedimentological difference within the sequence framework during the differential lake transgression,based on the investigation of the Paleogene lake basin evolution. The results showed that the fault slope-break slope architecture was well developed with back-stepping deltas and fan deltas during the slow lake transgression of the Member 3 of Shahejie Formation,in which forms thick high quality source rocks. The flexural-gentle slope architecture was well developed with mixed beach bar and small scale nearshore subaqueous fans(fan deltas)during the rapid transgression of the Member 1 of Shahejie Formation. The differential subsidence controlled the sequence architecture,paleogeomorphology and provenance supply,regulating the spatial lithological distribution. And there are significant differences in sequence architecture and sedimentary system during the different evolution stages of the lake basin. On this basis,the response model of sedimentary system characteristics under differential lacustrine transgression is established,which can be used for reference for oil and gas exploration,especially for lithologic oil and gas reservoir in the same type of basin.  相似文献   
108.
对数据缓存技术进行总结分析的基础上,首先提出了三层体系结构空间数据缓存模型,并针对各软件层空间数据管理及访问的特点,详细论述了各层空间数据缓存的实现方式;然后论述了三层体系结构中空间数据不一致的原因及各层空间数据一致性维护策略;最后对提出的三层体系结构下空间数据缓存策略进行了评价分析。  相似文献   
109.
软件开发是海洋监测技术与设备研究与开发的一个重要的环节,软件开发质量的高低直接关系到海洋监测仪器和设备的质量。文中阐释了以用户为中心的软件开发方法的概念、特点以及其实施中的基本原则和关键活动,并对传统的软件开发方法和以用户为中心的软件开发方法进行了比较研究。该方法不仅提高了用户的生产效率和生产质量,而且还减少了企业支持和培训方面的费用,提高了产品和服务的竞争力。  相似文献   
110.
曲流点坝内部剩余油形成与分布规律物理模拟   总被引:7,自引:0,他引:7  
建立了曲流点坝物理模型,模拟地下曲流点坝储层进行驱替实验。观察注入剂的运动规律,同时,在模型上布置了测量电极,以双电极法测量驱替过程中垂向电阻变化,反映注入剂波及高度的变化规律。分析了侧积泥岩夹层的建筑结构对注入剂在点坝砂体中的流动规律,以及对剩余油的形成分布的影响。通过实验研究证实,在曲流点坝内部,侧积泥岩夹层对注入剂具有强烈的遮挡作用,受其影响形成侧积体差异型剩余油、重力型剩余油以及压力异常型剩余油三种类型剩余油,主要分布在点坝的中上部。在实际生产中,利用水平井钻遇点坝上部进行开采是主要的手段。  相似文献   
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