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91.
针对低渗透油藏直井井网CO2驱油的不足,以大庆某低渗区块为例,建立反七点水平井井网CO2驱油地质模型。在物性参数相态拟合的基础上,对反七点水平井和五点直井两种不同井网模式的开发效果进行了对比,对反七点水平井井网参数进行了优化,同时对储层非均质(渗透率、储层非均质性、裂缝的发育情况等)进行了影响因素分析。研究表明:利用水平井注CO2可以适当地增大井距、排距,减少井的数量,降低钻井成本;在生产制度相同的情况下水平井井网的开发效果要比直井井网的开发效果好;在水平井井网中,采出程度随着油井到水平井的垂直距离的比值变化而变化,当比值为1.4时采出程度最大;水平井注CO2更适合低渗透正韵律储层;在储层裂缝发育的情况下,裂缝条数越多,CO2在储层中的不均匀推进现象越明显,最终采出程度越低。  相似文献   
92.
刘敏 《水文》2009,29(5)
本文详细阐述了采用矩形网格法绘制雨量等值线的原理、方法和步骤.提出了利用ASP+IIS直接在Internet上动态生成雨量等值线的功能实现和应用,为同行,特别是基层水文职工了解、掌握绘制雨量等值线的方法,有一定的参考价值.  相似文献   
93.
基于MapXtrme2004的WebGIS系统的研究与开发   总被引:6,自引:1,他引:5  
本文通过介绍.NET框架用于Web开发的主要技术ASP.NET和ADO.NET的技术优点以及MapInfo公司针对.NET环境开发的新组件Mapxtreme2004,通过分析Mapxtreme2004的结构组成总结了Mapxtreme2004用于WebGIS开发的主要方法类的用途,并着重研究了在.Net框架下利用Mapxtreme2004进行WebGIS开发的可行性及主要功能特点。  相似文献   
94.
《水文科学杂志》2013,58(4):655-664
Abstract

Palaeohydraulic modelling is presented for Athabasca Vallis, the youngest known catastrophic flood channel on Mars. This modelling incorporates three significant advantages over previous modelling of Martian channels: a step-backwater hydraulic model; more accurate topography; and improved flood height indicators. The maximum modelled palaeodischarge is between 1 × 106 and 2 × 106m3s?1 depending on the friction coefficient selected. An anomalously high palaeostage indicator suggests a region of ponded backwater in the channel in which streamlined forms were created through deposition, with the additional possibility of post-flood subsidence/lowering of the channel slope due to magma extrusion.  相似文献   
95.
Abstract

Fresh water is arguably the most vital resource for many aspects of a healthy and stable environment. Monitoring the extent of surface water enables resource managers to detect perturbations and long term trends in water availability, and set consumption guidelines accordingly. Potential end-users of water-related observations are numerous and reflect society as a whole. They encompass scientists and managers at all levels of government, aboriginal groups, water/power utility managers, farmers, planners, engineers, hydrologists, medical researchers, climate scientists, recreation enthusiasts, public school to post-graduate students, many special interest groups and the general public. Water data and analyses generate information products that benefit water resources planning and management, engineering design, plant operations, navigation activities, health research, water quality assessments and ecosystem management. As well, they serve as inputs for flood and drought warnings and weather and climate prediction models. Radar data in general, and RADARSAT in particular, are very good for detecting open surface water and have been used operationally for flood monitoring in many countries. Significant radar data archives now exist to analyse seasonal, annual and decadal trends, in order to attain a better understanding of the freshwater cycle. Radar data are also useful for wetland classification and soil moisture estimation. With the increasing pressure on water resources, both from a quality as well as a quantity perspective, the need will continue to increase for reliable information.

RADARSAT-2 has several innovations that will enhance the ability to provide useful information about water resources. This paper provides an overview of the use of radar in general, and RADARSAT-2 in particular, for the generation of information products useful to water resource managers.  相似文献   
96.
全球移动通讯系统GSM是目前较为广泛使用的一种数字移动通信网络。基于GSM及GIS技术,探讨了GSM Modem技术在地质灾害预警系统中的应用模式,研究了应用过程中涉及的部分关键技术和规范,并结合AT指令、ASP.NET和C#编程技术,设计、开发了基于Web技术的地质灾害数据采集与预警信息发布功能模块。最后,对该功能模块进行了应用试验,结果令人满意。  相似文献   
97.
On the basis of the authors' experiences of setting up an NGDC Web site, this paper attempts to present some significant aspects about the security of NGDC based on ASP. They include data storing, database maintenance, new technical support and so on. Firstly, this paper discusses how to provide the security of data which is saved in the hosts of NGDC. The security model of “Networks-DB Server-DB-DB Object” is also presented. In Windows NT Server, Internet Information Server (i. e., IIS) is in charge of transferring message and the management of Web sites. ASP is also based on IIS. The advantages of virtual directory technique provided by IIS are emphasized.  相似文献   
98.
The prolonged mei-yu/baiu system with anomalous precipitation in the year 2020 has swollen many rivers and lakes,caused flash flooding,urban flooding and landslides,and consistently wreaked havoc across large swathes of China,particularly in the Yangtze River basin.Significant precipitation and flooding anomalies have already been seen in magnitude and extension so far this year,which have been exerting much higher pressure on emergency responses in flood control and mitigation than in other years,even though a rainy season with multiple ongoing serious flood events in different provinces is not that uncommon in China.Instead of delving into the causes of the uniqueness of this year’s extreme precipitation-flooding situation,which certainly warrants in-depth exploration,in this article we provide a short view toward a more general hydrometeorological solution to this annual nationwide problem.A“glocal”(global to local)hydrometeorological solution for floods(GHS-F)is considered to be critical for better preparedness,mitigation,and management of different types of significant precipitation-caused flooding,which happen extensively almost every year in many countries such as China,India and the United States.Such a GHS-F model is necessary from both scientific and operational perspectives,with the strength in providing spatially consistent flood definitions and spatially distributed flood risk classification considering the heterogeneity in vulnerability and resilience across the entire domain.Priorities in the development of such a GHS-F are suggested,emphasizing the user’s requirements and needs according to practical experiences with various flood response agencies.  相似文献   
99.
胜利油田渤19区块注交联聚合物开采多年后,因注入水的水质不达标导致聚合物过度交联形成强凝胶,造成聚合物注入区块许多油水井的堵塞。对现场聚合物垢样品所做的化学组分、表面元素能谱及红外光谱的研究表明,垢的主体结构由交联的聚丙烯酰胺组成,交联体吸收了大量水分,在交联体内小环境中因富集而形成氯化物矿物晶体无机垢结构,而在成垢的过程中又将地层内的一些粘土矿物包裹于交联体内,形成具有聚合物-矿物复合结构的强胶凝态物质,严重影响聚合物注入—调剖—驱油过程中的聚合物溶液的流动。  相似文献   
100.
对滑坡变形监测资料进行有效地管理和计算分析是滑坡稳定性评价和预测预报的一项基础而关键的工作.GIS技术可实现滑坡变形监测资料的可视化管理,结合其空间分析功能可使滑坡变形分析更全面.Web技术则可以实现不同区域或不同工程的滑坡监测的集中数据存储、多终端维护与多层次的查询服务.利用ASP.NET、ArcGIS Server...  相似文献   
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