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71.
基于方差分量估计的自适应融合导航 总被引:23,自引:4,他引:23
多源传感器观测信息的精度一般不一致,利用方差分量估计理论可以合理地顾及各传感器观测信息在融合导航解中的权比.首先给出基于多源观测信息的融合导航解算模式,进而基于方差分量估计讨论了各传感器观测信息在融合导航解中的合理平衡问题,然后应用自适应因子顾及动力学模型预报信息的贡献,给出了计算过程,并利用模拟数据进行了试算与比较. 相似文献
72.
关注我国“工业测量”事业的发展 总被引:1,自引:0,他引:1
尝试给出工业测量的定义、范畴、目标的分类和多样性,简要叙述工业测量手段的多样性,列举待研制和待改进的工业测量集成系统的名称以及所依托的几何传感器的类别。 相似文献
73.
Introduction China is a country with many landslides and debris flows. These disasters bring out a large amount of losses of life and property. It is significant to predict landslide incident by monitoring the deformations of these landslides. At past, triangulation and trilateration are traditional tools, but it is very difficult for them to realize real-time monitoring, and it is more dangerous for obser- vation workers when the deformation becomes larger. Because of many advantages such as… 相似文献
74.
A Possible Detection of the 26 December 2004 Great Sumatra-Andaman Islands Earthquake with Solution Products of the International GNSS Service 总被引:1,自引:0,他引:1
J. Kouba 《Studia Geophysica et Geodaetica》2005,49(4):463-483
The main goal of this work is to critically review the IGS solution products and Precise Point Positioning (PPP) in order
to demonstrate their potential to contribute to studies of large earthquakes such as the one that devastated Southeast Asia
on December 26th, 2004. In view of a possible detection of the Mw 9.0 Sumatra-Andaman Islands Earthquake of December 26, 2004,
position solutions, ranging from intervals of years to one second, of four International GNSS Service (IGS) stations within
3000 km of the epicenter were examined. The IGS combined, cumulative solution product (IGS04P51), consisting of epoch and
station velocity solutions and based on data spans of several years prior to the earthquake, was used as a reference. Four
IGS combined weekly position solutions (igs04P1301-4), two weeks before and after the earthquake, were utilized for the weekly
solution resolution. PPP static and kinematic solutions with IGS Final combined orbits and clocks were used for the mean daily
and instantaneous 5-min and 1-sec epoch solutions, respectively. The most significant changes, detected by both weekly and
daily solutions occurred in longitude. The nearest IGS station ntus, about 1000 km east of the epicenter, moved westward about
15 mm, while the more distant Indian station iisc (∼ 2300 km NW from the epicenter), shifted about 15 mm eastward. In spite
of position errors caused by interpolation of the 5-min IGS clocks, the 1-sec solutions, based on separate data sets, available
only for two stations (iisc, dgar), still showed seismic surface waves, in particular at the Indian station iisc. Precise
daily IGS combined polar motion and length-of-day products, after correcting for the atmospheric effects, also likely detected,
statistically significant, anomalistic excitations on December 26, 2004 that could be caused by this great earthquake. 相似文献
75.
文章介绍区域地质背景、矿区地物化特征,对成矿时代、流体包裹体特征进行初步研究,并指出找矿远景,希望对矿区的矿产勘查具有借鉴和指导意义。 相似文献
76.
Pascal Willis Claude Boucher Hervé Fagard Zuheir Altamimi 《Comptes Rendus Geoscience》2005,337(7):653-662
IGN is in charge of the installation and maintenance of the DORIS orbit determination network. More recently, in collaboration with JPL, precise geodetic computations were performed. The goal of this paper is to recall the various historic contributions of IGN to the DORIS system in their international context and then to describe a new estimation technique developed for a multi-satellite mode, making full profit of a better modeling for satellites and ground clocks as well as tropospheric correction parameters. Derived geodetic results demonstrate a precision in the order of 1 cm for station positions. To cite this article: P. Willis et al., C. R. Geoscience 337 (2005). 相似文献
77.
The exponential decline in saturated hydraulic conductivity with depth: a novel method for exploring its effect on water flow paths and transit time distribution 下载免费PDF全文
The strong vertical gradient in soil and subsoil saturated hydraulic conductivity is characteristic feature of the hydrology of catchments. Despite the potential importance of these strong gradients, they have proven difficult to model using robust physically based schemes. This has hampered the testing of hypotheses about the implications of such vertical gradients for subsurface flow paths, residence times and transit time distribution. Here we present a general semi‐analytical solution for the simulation of 2D steady‐state saturated‐unsaturated flow in hillslopes with saturated hydraulic conductivity that declines exponentially with depth. The grid‐free solution satisfies mass balance exactly over the entire saturated and unsaturated zones. The new method provides continuous solutions for head, flow and velocity in both saturated and unsaturated zones without any interpolation process as is common in discrete numerical schemes. This solution efficiently generates flow pathlines and transit time distributions in hillslopes with the assumption of depth‐varying saturated hydraulic conductivity. The model outputs reveal the pronounced effect that changing the strength of the exponential decline in saturated hydraulic conductivity has on the flow pathlines, residence time and transit time distribution. This new steady‐state model may be useful to others for posing hypotheses about how different depth functions for hydraulic conductivity influence catchment hydrological response. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
78.
统计数据基于地理信息的集成,可以弥补传统的统计信息单一、不直观的表现形式,充分发挥其在政府管理决策中所起的重要作用以及对社会发展的导向作用。本文通过研究建立综合统计数据模型,阐述了数据来源、数据组织、空间数据模型建立及查询逻辑。以安徽省综合信息服务系统为例,在基于天地图·安徽的地图服务和Arc GIS API For Flex开发包的基础上,完成Flex框架下的客户端设计,采用Web Service数据通信技术来完成综合统计信息服务系统的设计与实现。 相似文献
79.
董星星 《测绘与空间地理信息》2016,(1):153-155
从土地执法监察管理的实际需求出发,探讨了基于"一张图"平台的国土资源执法监察系统建设方案,设计了土地执法监察系统结构和功能模块,并进一步给出了土地执法监察数据库建设和数据交换的技术方法。该系统方案的应用将有利于快速、准确地监控国土资源违法行为,强化对国土资源违法行为的监控能力,有效地提高了国土部门执法监察工作效率和执法水平。 相似文献
80.
城镇地下管线就像是城镇的脉络,对于城镇的运转非常重要,肩负着为城镇运送物质能量、输出废弃物的重要使命。随着城镇的扩建,敷设于地下的管线不断向周围扩张,其规模不断膨胀,因此,也变得越来越复杂。传统的管线管理方式不仅数据的查询效率低,导致因管线错挖而造成的爆管事故频发,而且不能及时准确地进行应急处理。所以在告别传统落后的地下管线管理方式的同时,我们应思考如何能够更好的管理大量的地下管线数据,从而提高了数据的查询与应急管理的效率,为城镇规划和发展提供更好的支撑作用。 相似文献