排序方式： 共有2条查询结果，搜索用时 31 毫秒
1
1.
An extensive study collected in situ data along the Yellow Sea(YS) and East China Sea(ECS) to assess the radiometric properties and the concentration of the water constituents derived from Moderate Resolution Imaging Spectroradiometer(MODIS). Thirteen high quality match-ups were obtained for evaluating the MODIS estimates of Rrs(λ), chlorophyll a(Chl a) and concentrations of suspended particulate sediment matter(SPM). For MODIS Rrs(λ), the mean absolute percentage difference(APD) was in the range of 20%–36%, and the highest uncertainty appeared at 412 nm, whereas the band ratio of Rrs(λ) at 488 nm compared with that at 547 nm was highly consistent, with an APD of 7%. A combination of near-infrared bands and shortwave infrared wavelengths atmosphere correction algorithm(NIR-SWIR algorithm) was applied to the MODIS data, and the estimation accuracy of Rrs were improved at most of the visible spectral bands except 645 nm, 667 nm and 678 nm. Two ocean-colour empirical algorithms for Chl a estimation were applied to the processed data, the results indicated that the accuracy of the derived Chl a values was obviously improved, the four-band algorithms outperformed the other algorithm for measured and simulated datasets, and the minimum APD was 35%. The SPM was also quantified. Two regional and two coastal SPM algorithms were modified according to the in situ data. By comparison, the modified Tassan model had a higher accuracy for the application along the YS and ECS with an APD of 21%. However, given the limited match-up dataset and the potential influence of the aerosol properties on atmosphere correction, further research is required to develop additional algorithms especially for the low Chl a coastal water. 相似文献
2.
彼此相邻的海域之间由于用海类型的不同,经常存在相互的干扰和影响。本文以国家海洋功能区划中规定的海洋功能区分类及海洋环境保护要求为基础,设计了用海变化的自动检测方法。根据不同海洋功能分区的海水水质质量的标准建立缓冲区检测算法和历史用海检测算法,缓冲区检测算法用来检测同一时期不同位置的用海是否存在冲突;历史用海检测算法用来检测同一位置不同时期的用海是否存在冲突。在两种检测算法的基础上,利用地理信息系统开发组件实现了对新加入宗海及原宗海用海变更的自动检测功能,并以上海海洋功能区划数据为测试数据,验证了作为海籍空间信息管理系统的核心功能之一,可以实现用海变化的自动检测,满足对宗海空间变化和时间变化的信息化管理。 相似文献
1