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821.
黄卫祖 《吉林大学学报(地球科学版)》1993,(1)
分别论述了在空间域与频率域中由重力资料反演三维密度分布的理论及其实现的方法,并提出了一种简便、实用的频率域三维密度反演算法。 相似文献
822.
测量数据可视化技术研究 总被引:3,自引:2,他引:1
介绍可视化的基本原理,阐述中视化研究的必要性,探讨测量数据可视化的技术手段,给出了可视化技术在工作形变监测及工业测量中应用情景,提出一些结论和建议。 相似文献
823.
WANG Yandong GONG Jianya HUANG Juntao DENG Yuejin WANG Yangdong Doctoral Candidate National Laboratory for Information Engineering in Surveying Mapping Remote Sensing WTUSM Luoyu Road Wuhan China 《地球空间信息科学学报》1999,2(1):104-108
Geo-Spatial Data Transfer Standard is an important part of "National Spatial Data Infrastructure(NSDI)" ,as well as a necessary means for data sharing. "Chinese National Geo-Spatial Data Transfer Format (CNSDTF)" was approved by National Quality Technology Supervise Bureau in 1999 with the standard serial number of 17798-1999. It is designed to support vector and raster spatial data. This paper describes the vector part of CNSDTF, including design ideas, main characters, conceptual model, definition of spatial object, and file structure. 相似文献
824.
松辽盆地北部三分量地震勘探的主要任务是检测天然气的分布范围,预测岩性油气藏。三分量地震勘探的最大难点是采集上压制随机干扰,处理上去除转换波剖面上同相轴的人为的直立错断(由于通常处理软件不佳引起)。着重介绍了三分量地震勘探的采集原理和处理方法。本次试验取得了良好的三分量剖面。 相似文献
825.
ABSTRACTThe sharing of data and collection of new data are both essential, but they are not inherently complementary. When data are openly available, researchers may be motivated to use those data rather than collect more because field work has costs and risks. The competitive advantage to those who do not put resources towards fieldwork may discourage field hydrology. Allocating efforts towards generating field data, which benefits hydrological sciences, is not necessarily best for individual hydrologists, especially in an era of open data. The objective of this work is to open a conversation on whether individuals’ best interests may contrast with the community’s desire for new observations. If the community wants new field observations, there is a need to consider the shifting balance of incentives and disincentives for pursuing field studies in hydrology. 相似文献
826.
ABSTRACTWe thank Allen and Berghuijs for continuing the discussion on field hydrology and data sharing and discuss two incentives to promote data collection and sharing in hydrological sciences: a collaborative attitude and additional funding to make data publicly available. 相似文献
827.
Michael Silberbauer 《水文科学杂志》2020,65(5):726-734
ABSTRACTNational and regional water quality monitoring networks have been operated in South Africa since the early 1970s. These originally had text-based inventories that were convenient for specialists who were familiar with the national networks and knew the locations of their sites of interest. However, within two decades the networks had expanded in geographical extent and variables monitored to such an extent that users needed spatial context in order to locate sites that fitted their information requirements. Mapping applications running on the Internet, such as Google Earth and Leaflet, form the foundation of a system for providing online inventories and summaries of the data available on the water quality database. The interfaces were constructed using available software, mainly ArcInfo and R. A recent concern is a decrease in the collection of water quality data, which is reducing the value of data summaries for water resource management. 相似文献
828.
ABSTRACTAdvances in open data science serve large-scale model developments and, subsequently, hydroclimate services. Local river flow observations are key in hydrology but data sharing remains limited due to unclear quality, or to political, economic or infrastructure reasons. This paper provides methods for quality checking openly accessible river-flow time series. Availability, outliers, homogeneity and trends were assessed in 21 586 time series from 13 data providers worldwide. We found a decrease in data availability since the 1980s, scarce open information in southern Asia, the Middle East and North and Central Africa, and significant river-flow trends in Africa, Australia, southwest Europe and Southeast Asia. We distinguish numerical outliers from high-flow peaks, and integrate all investigated quality characteristics in a composite indicator. We stress the need to maintain existing gauging networks, and highlight opportunities in extending existing global databases, understanding drivers for trends and inhomogeneity, and in innovative acquisition methods in data-scarce regions. 相似文献
829.
Nans Addor Hong X. Do Camila Alvarez-Garreton Gemma Coxon Keirnan Fowler Pablo A. Mendoza 《水文科学杂志》2020,65(5):712-725
ABSTRACTLarge-sample hydrology (LSH) relies on data from large sets (tens to thousands) of catchments to go beyond individual case studies and derive robust conclusions on hydrological processes and models. Numerous LSH datasets have recently been released, covering a wide range of regions and relying on increasingly diverse data sources to characterize catchment behaviour. These datasets offer novel opportunities, yet they are also limited by their lack of comparability, uncertainty estimates and characterization of human impacts. This article (i) underscores the key role of LSH datasets in hydrological studies, (ii) provides a review of currently available LSH datasets, (iii) highlights current limitations of LSH datasets and (iv) proposes guidelines and coordinated actions to overcome these limitations. These guidelines and actions aim to standardize and automatize the creation of LSH datasets worldwide, and to enhance the reproducibility and comparability of hydrological studies. 相似文献
830.
Heidi Kreibich Veit Blauhut Jeroen C. J. H. Aerts Laurens M. Bouwer Henny A. J. Van Lanen Alfonso Mejia 《水文科学杂志》2020,65(3):491-494
ABSTRACTWe thank the authors, Brunella Bonaccorso and Karsten Arnbjerg-Nielsen for their constructive contributions to the discussion about the attribution of changes in drought and flood impacts. We appreciate that they support our opinion, but in particular their additional new ideas on how to better understand changes in impacts. It is great that they challenge us to think a step further on how to foster the collection of long time series of data and how to use these to model and project changes. Here, we elaborate on the possibility to collect time series of data on hazard, exposure, vulnerability and impacts and how these could be used to improve e.g. socio-hydrological models for the development of future risk scenarios. 相似文献