地震红外长波辐射短期异常特征分析     

李继业  任建辉  高峰  胡滨生  孟令蕾 《中国地震》2011,27(4):410-418

利用NOAA卫星资料反演的地震长波辐射值OLR对黑龙江及其周边2003年以来8次中强地震进行了追踪研究.结果显示,震前2个月左右OLR场值存在明显的高值异常区,未来震中距离高值区中心点250km(优势距离为160km).该方法对黑龙江及其周边4级以上地震短期判定可能具有一定的指示价值,也为利用卫星遥感技术预测未来可能发震区域并及时做出短期预测预警提供了新途径.  相似文献   

VP型宽频带倾斜仪映震能力分析     

王强  孟建国  吕春帅  曲保安  卢双苓  孙豪 《地震地磁观测与研究》2011,32(4):94-98

根据所掌握的仪器映震能力、震前(后)大震特殊捕捉现象,以及对相同地震不同仪器映震的对比,可以看出,VP型宽频带垂直摆倾斜仪具备前兆仪器捕捉(反映)地震孕育及地震发生的相关作用,能够正确、客观的作用于地震前兆数据产出,对地震预测研究具有深远影响.  相似文献   

Experimental investigation on seismic behavior of single piles in sandy soil     

Werasak Raongjant 《地震工程与工程振动(英文版)》2011,10(3):417-422

This paper describes a quasi-static test program featuring lateral cyclic loading on single piles in sandy soil. The tests were conducted on 18 aluminum model piles with different cross sections and lateral load eccentricity ratios, e/d, (e is the lateral load eccentricity and d is the diameter of pile) of 0, 4 and 8, embedded in sand with a relative density of 30% and 70%. The experimental results include lateral load-displacement hysteresis loops, skeleton curves and energy dissipation curves. Lateral capacity, ductility and energy dissipation capacity of single piles under seismic load were evaluated in detail. The lateral capacities and the energy dissipation capacity of piles in dense sand were much higher than in loose sand. When embedded in loose sand, the maximum lateral load and the maximum lateral displacement of piles increased as e/d increased. On the contrary, when embedded in dense sand, the maximum lateral load of piles decreased as e/d increased. Piles with a higher load eccentricity ratio experienced higher energy dissipation capacity than piles with e/d of 0 in both dense and loose sand. At a given level of displacement, piles with circular cross sections provided the best energy dissipation capacity in both loose and dense sand.  相似文献   

导航数字地图的快速显示技术研究     

高扬  杨志强  乌萌 《测绘科学》2011,36(3):236-238,229

针对车辆导航系统中地图显示问题,本文设计了"LOD层+多层四叉树+R树"三级索引结构,对现有的四叉树分块方式进行了改进,提出了基于多层四叉树空间分块和块内根据R树分包的数据组织方案,有效解决了覆盖多个网格的要素存放问题;提出了多层和多块的数据缓冲区结构,以及相应的数据后台预取和更新策略,提高了教据提取效率.试验结果表明...  相似文献   

Application of Spatial Database in Quantitative Analysis of Litho-Paleogeography—A Case Study of a Middle Ordovician Sequence Interval in the Ordos Basin     

Bin Li  Feiyan Liao  Hao Meng  Yanchun Zhong 《地球空间信息科学学报》2011,14(1):27-38

In the study of sequence stratigraphy and litho-paleogeography,quantitative analysis,precise calculation and detailed comparison of tremendous geological data,such as field profiles,logging records and seismic curves from different areas,are the basic requirements.In order to obtain a more reliable and precise result,this paper presents a novel method that combines spatial database analysis with the single-factor mapping technology to establish sequence stratigraphical succession and to map the Ordo-vician litho-paleogeography of the Ordos Basin,one of the largest oil-gas bearing basins in North China Platform.By using this method,all of the related basic geological data can be quantitatively analyzed and effectively managed.Various attributes of the ba-sic stratigraphic units and their characters,such as sequence thickness,penecontemporaneous dolostone content,shallow water parget content,and terrigenous material content,can be fully utilized statistically in facies analysis and in mapping.Based on this analysis,this paper has be exerted single-factor isopachous mapping quantitatively for each of the Ordovician sequences in the ba-sin,and finally synthesized multiple factors to reconstruct the litho-paleogeography for each of the sequence intervals.The study shows that the proposed method is quite effective and has a much higher resolution in recognizing litho-paleogeographic subunits compared with traditional ways.For example,in one of the Middle Ordovician sequence intervals(SQ19 in the Lower Majiagou Formation) of the Ordos Basin,the authors have successfully developed a mathematical formula to divide the distribution of various facies units substantially,such as old lands,submarine uplifts,supratidal zones,intertidal zones and subtidal zones.  相似文献   

Shell model representation as a substitute of LoD3 for 3D modeling in CityGML     

Hongchao Fan  Bo Mao  Jie Shen  Liqiu Meng 《地球空间信息科学学报》2011,14(2):79-84

The OGC standard for 3D city modeling is widely used in an increasing number of applications.It defines five consecutive Levels of Detail(LoD0 to LoD4 with increasing accuracy and structural complexity),in which LoD3 includes all exterior appearances and geometrical details and subsequently requires much storage space.A new LoD is introduced as shell model with the exterior shell of the LoD3 model and the opening objects like windows,doors as well as smaller faade objects are projected onto walls.In this paper,a user survey is presented.The results of this survey show that the shell model can give users almost the same visual impression as the LoD3 model.Furthermroe,algorithms are developed to extract the shell model from LoD3 model.Experiments show that this shell model can reduce up to 90% storage of the original LoD3 model.Therefore,on one hand it can be used as a substitute for a LoD3 model for the visualization on small displays.On the other hand,it can be treated as a sub-level of detail(SLoD3) in CityGML,since it retains almost the same amount of information but requires much less storage space.  相似文献   

专题地理信息数据可靠性评价方法     

胡丹露  王靳辉  魏萌 《测绘科学技术学报》2011,(6):391-394

可靠性评价是说明地理信息数据质量的一种方法。针对专题地理信息数据结构的特点,分析了数据的完整性、可用性、一致性、现势性、正确性等诸多因素。运用模糊数学中的模糊综合评判原理,在"领域专家具备处理地理数据正确性评价这个模糊问题的能力"的前提下,建立了地理实体属性数据、坐标数据、多媒体数据可靠性多层次综合评价的数学模型。该模型保留了专家评价的全部信息,降低了主观评价的武断性;同时简化了人工评价,保证了可靠性评价的可信度。  相似文献   

综合气象观测运行监控系统   总被引：15，自引：1，他引：14  

梁海河  孟昭林  张春晖  李雁 《气象》2011,37(10):1292-1300

为了提高我国气象装备运行保障能力和观测数据质量,中国气象局气象探测中心从2006年起创建了综合气象观测运行监控系统,并依此逐步建立了监控业务。文中围绕气象装备保障业务关于台站、省级和国家级的三级用户需求,明确了以探测设备运行状态监视、技术保障信息管理、观测数据质量监视为主线的监控业务设计思想,并奠定了监控业务系统的技术框架,提出了＂两级布设、三级应用＂的分布结构,基于互联网和WebGIS技术,建立了一套实时气象观测网运行监控和分析系统,具备实时设备运行状态监控、装备保障信息管理、观测数据质量监视、基础信息管理、运行统计评估等功能。在此基础上,文中介绍了气象观测运行监控业务概况,通过监控系统实现了对全网设备运行状况的实时掌握,开展监控产品分析服务,定期评估装备运行效能和数据质量状况,使重要气象装备如天气雷达的可用性大幅提升,为提高气象装备运行效能发挥了重要作用。  相似文献   

城镇化、郊区化与中国城市空间扩张     

龙茂乾  孟晓晨 《地域研究与开发》2015,(3)

城市经济学的理论表明,城市人口增长和交通改善等因素都会导致城市的空间扩张,但其作用的机理不同。结合中国的情况,将城市空间扩张的影响因素分为城镇化和郊区化2个市场化动力,二者都会推动城市空间扩张,导致城市边界向外延伸。历年截面数据和面板数据分析结果都表明,在中国城市空间扩张进程中,城镇化动力和郊区化动力都在起作用,城镇化动力占主导地位,与此同时,郊区化动力也有增强的趋势。人口增长和交通改善推动城市空间扩张,城市建成区面积扩张的推动力远大于阻力。作为城市空间扩张速度变化的分水岭以及市场作用下收入水平显著性改变的分界点,1998年的住房制度改革对于中国城市空间扩张进程有着里程碑式的意义。  相似文献   

区域合作背景下服务业发展的收敛性研究——以大珠三角金融业为例     

钟韵  吴蒙 《热带地理》2015,35(2)

文章基于经济增长收敛理论,从区域合作视角,展开服务业发展收敛性研究.包括阐释服务业发展收敛的内涵、与经济增长收敛的关联、服务业发展的收敛机制,以及分析服务业发展收敛的模型与指标选择,并最终运用所构建的方法,对CEPA实施后大珠江三角洲的金融业收敛性进行了实证检验.结果显示,2004-2008年该区域金融业发展呈发散趋势.这一结果与近年来以其他方法与指标检验金融收敛性得出的结论基本一致,证实了基于经济增长收敛理论及分析模型的服务业发展收敛研究思路与分析模型具有可信性与可行性,亦从一个侧面对大珠三角金融合作的成效作出了评判.  相似文献