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上海农业集成系统是基于JZ地理信息系统软件(精准农业信息公司开发的一套基于Web发布的地理信息系统发布引擎)开发的一套BS架构的农业系统。该平台采用了ASP.NET技术、SQL Server数据库管理技术以及地图发布引擎(JZ地图引擎)等技术,将传感器采集到的实时数据发布到网上,使各种不同目的的客户能够及时了解、分析和处理数据,并根据数据的实际情况及时应对农作物生长过程中的不良状态。本文对该平台的关键技术、数据管理、功能模块和安装步骤等方面作了详细的介绍。 相似文献
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基于DEM的遥感数据复原方法研究 总被引:1,自引:0,他引:1
介绍了一种基于数字高程模型(DEM)的遥感数据复原新方法。此方法将地形因子作为最主要的作用因子,不考虑卫星传感过程中的随机影响。首先,根据基础地理数据,按其等高线层生成DEM; 然后,利用DEM,通过实测样点、DEM和经过纠正的遥感数据的信息融合,进行遥感数据中像元样点的坡度、坡向分析,建立DEM与遥感信息的相关关系模型,以数学统计方法描述地形因子对遥感数据的作用机理; 最后,进行逐像元的遥感信息复原(归一化)。结果表明,该方法具有较好的信息复原效果,可消除或减少地形对遥感数据的影响,增强遥感技术在山区复杂地形下的实用性。 相似文献
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Clementine UVVIS and NIR data from the lunar sampling sites (totaling 46 sampling sites) were processed and used to refine the iron determination method of Le Mouéic et al. (2000, 2002). We found that about 21 sampling sites are unsuitable to Le Mouéic et al's spectral parameters ("slope" and "depth l") because their 1500 nm filter could not be used as spectral parameters' right shoulders and to evaluate the depth of the 1-μm absorption feature accurately. We used the rest 25 sampling sites to refine the method developed by Le Mouéic et al. (2000, 2002 ) and obtained our own equation of FeO content determination. We tested our own equation, and the results are satifactory. In our work we also acquired some useful experiences in scientific applications of our own dataset of the Chang'E-1 mission. 相似文献
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Adam Carter Benjamin van Wyk de Vries Karim Kelfoun Patrick Bachèlery Pierre Briole 《Bulletin of Volcanology》2007,69(7):741-756
A clear model of structures and associated stress fields of a volcano can provide a framework in which to study and monitor
activity. We propose a volcano-tectonic model for the dynamics of the summit of Piton de la Fournaise (La Reunion Island,
Indian Ocean). The summit contains two main pit crater structures (Dolomieu and Bory), two active rift zones, and a slumping
eastern sector, all of which contribute to the actual fracture system. Dolomieu has developed over 100 years by sudden large
collapse events and subsequent smaller drops that include terrace formation. Small intra-pit collapse scars and eruptive fissures
are located along the southern floor of Dolomieu. The western pit wall of Dolomieu has a superficial inward dipping normal
fault boundary connected to a deeper ring fault system. Outside Dolomieu, an oval extension zone containing sub-parallel pit-related
fractures extends to a maximum distance of 225 m from the pit. At the summit the main trend for eruptive fissures is N80°,
normal to the north–south rift zone. The terraced structure of Dolomieu has been reproduced by analogue models with a roof
to width ratio of approximately 1, suggesting an original magma chamber depth of about 1 km. Such a chamber may continue to
act as a storage location today. The east flank has a convex–concave profile and is bounded by strike-slip fractures that
define a gravity slump. This zone is bound to the north by strike-slip fractures that may delineate a shear zone. The southern
reciprocal shear zone is probably marked by an alignment of large scoria cones and is hidden by recent aa lavas. The slump
head intersects Dolomieu pit and may slide on a hydrothermally altered layer known to be located at a depth of around 300 m.
Our model has the summit activity controlled by the pit crater collapse structure, not the rifts. The rifts become important
on the mid-flanks of the cone, away from pit-related fractures. On the east flank the superficial structures are controlled
by the slump. We suggest that during pit subsidence intra-pit eruptions may occur. During tumescence, however, the pit system
may become blocked and a flank eruption is more likely. Intrusions along the rift may cause deformation that subsequently
increases the slump’s potential to deform. Conversely, slumping may influence the east flank stress distribution and locally
control intrusion direction. These predictions can be tested with monitoring data to validate the model and, eventually, improve
monitoring. 相似文献
109.
DL-101C数字水准仪水准测量精度研究 总被引:1,自引:0,他引:1
在对DL-101C数字水准仪工作性能测试的基础上进行观测精度评价,总结观测经验为该仪器投入生产使用打下基础。 相似文献
110.
K. R. Koch 《Journal of Geodesy》2007,81(9):581-591
Among the Markov chain Monte Carlo methods, the Gibbs sampler has the advantage that it samples from the conditional distributions
for each unknown parameter, thus decomposing the sample space. In the case the conditional distributions are not tractable,
the Gibbs sampler by means of sampling-importance-resampling is presented here. It uses the prior density function of a Bayesian
analysis as the importance sampling distribution. This leads to a fast convergence of the Gibbs sampler as demonstrated by
the smoothing with preserving the edges of 3D images of emission tomography. 相似文献