高分辨率遥感技术在厦门海湾生态环境调查中的应用   总被引：5，自引：0，他引：5  

林桂兰  孙飒梅  曾良杰  庄世坚 《台湾海峡》2003,22(2):242-247,T003

对于局部区域研究，高分辨率卫星遥感及其影像的智能化处理技术是获取信息的新手段．本文以IKONOS遥感影像在厦门海湾的应用为例，探讨高分辨率遥感卫星影像应用于海湾生态环境调查与分析的应用技术．通过分析高分辨率影像地物特征，提出高分辨率遥感影像的重要处理技术：采用不同缩放尺度进行分类和利用空间特征及纹理结构进行专题信息提取。  相似文献   

The impact of the M₂ internal tide on data-assimilative model estimates of the surface tide     

E.D. Zaron  G.D. Egbert   《Ocean Modelling》2007,18(3-4):210-216

We use a synthetic data experiment to assess the accuracy of ocean tides estimated from satellite altimetry data, with emphasis on the impact of the phase-locked internal tide, which has a surface expression of several centimeters near its sites of genesis. Previous tidal estimates have regarded this signal as a random measurement error; however, it is deterministic and not scale-separated from the barotropic (surface) tide around complex bathymetric features. The synthetic data experiments show that the internal tide has a negligible impact on the barotropic tidal fields inferred under these circumstances, and the barotropic dissipation (a quadratic functional of the tidal fields) is in good agreement with the energetics of the three-dimensional regional primitive equations model which is the source of the synthetic data.  相似文献   

南沙群岛珊瑚礁地貌图像信息管理系统     

傅孙成  钟晋梁  张乔民  刘清祥  熊永兰 《热带海洋学报》1998,(3)

运用面向对象的软件开发技术,结合珊瑚礁地貌学、计算机图像学和计算机信息管理技术,在Windows平台上研制开发出南沙群岛珊瑚礁地貌图像信息管理系统。该系统集文件管理、数据库管理和图形、图像管理于一体,具有信息检索输出、信息编辑和信息维护等功能,以图形用户介面交互,达到"所见即所得"的效果。  相似文献   

4D seismic time-lapse monitoring of an active cold vent,northern Cascadia margin   总被引：1，自引：1，他引：1  

Michael Riedel 《Marine Geophysical Researches》2007,28(4):355-371

Two single-channel seismic (SCS) data sets collected in 2000 and 2005 were used for a four-dimensional (4D) time-lapse analysis of an active cold vent (Bullseye Vent). The data set acquired in 2000 serves as a reference in the applied processing sequence. The 4D processing sequence utilizes time- and phase-matching, gain adjustments and shaping filters to transform the 2005 data set so that it is most comparable to the conditions under which the 2000 data were acquired. The cold vent is characterized by seismic blanking, which is a result of the presence of gas hydrate in the subsurface either within coarser-grained turbidite sands or in fractures, as well as free gas trapped in these fracture systems. The area of blanking was defined using the seismic attributes instantaneous amplitude and similarity. Several areas were identified where blanking was reduced in 2005 relative to 2000. But most of the centre of Bullseye Vent and the area around it were seen to be characterized by intensified blanking in 2005. Tracing these areas of intensified blanking through the three-dimensional (3D) seismic volume defined several apparent new flow pathways that were not seen in the 2000 data, which are interpreted as newly generated fractures/faults for upward fluid migration. Intensified blanking is interpreted as a result of new formation of gas hydrate in the subsurface along new fracture pathways. Areas with reduced blanking may be zones where formerly plugged fractures that had trapped some free gas may have been opened and free gas was liberated.  相似文献   

Fast static correction methods for high-frequency multichannel marine seismic reflection data: A high-resolution seismic study of channel-levee systems on the Bengal Fan     

Martin Gutowski  Monika Breitzke  Volkhard Spieß 《Marine Geophysical Researches》2002,23(1):57-75

Very high-frequency marine multichannel seismic reflection data generated by small-volume air- or waterguns allow detailed, high-resolution studies of sedimentary structures of the order of one to few metres wavelength. The high-frequency content, however, requires (1) a very exact knowledge of the source and receiver positions, and (2) the development of data processing methods which take this exact geometry into account. Static corrections are crucial for the quality of very high-frequency stacked data because static shifts caused by variations of the source and streamer depths are of the order of half to one dominant wavelength, so that they can lead to destructive interference during stacking of CDP sorted traces. As common surface-consistent residual static correction methods developed for land seismic data require fixed shot and receiver locations two simple and fast techniques have been developed for marine seismic data with moving sources and receivers to correct such static shifts. The first method – called CDP static correction method – is based on a simultaneous recording of Parasound sediment echosounder and multichannel seismic reflection data. It compares the depth information derived from the first arrivals of both data sets to calculate static correction time shifts for each seismic channel relative to the Parasound water depths. The second method – called average static correction method – utilises the fact that the streamer depth is mainly controlled by bird units, which keep the streamer in a predefined depth at certain increments but do not prevent the streamer from being slightly buoyant in-between. In case of calm weather conditions these streamer bendings mainly contribute to the overall static time shifts, whereas depth variations of the source are negligible. Hence, mean static correction time shifts are calculated for each channel by averaging the depth values determined at each geophone group position for several subsequent shots. Application of both methods to data of a high-resolution seismic survey of channel-levee systems on the Bengal Fan shows that the quality of the stacked section can be improved significantly compared to stacking results achieved without preceding static corrections. The optimised records show sedimentary features in great detail, that are not visible without static corrections. Limitations only result from the sea floor topography. The CDP static correction method generally provides more coherent reflections than the average static correction method but can only be applied in areas with rather flat sea floor, where no diffraction hyperbolae occur. In contrast, the average static correction method can also be used in regions with rough morphology, but the coherency of reflections is slightly reduced compared to the results of the CDP static correction method.  相似文献   

Neural network for wave forecasting among multi-stations     

Ching-Piao Tsai  Chang Lin  Jia-N Shen 《Ocean Engineering》2002,29(13):1685-1695

Unlike in the open sea, the use of wind information for forecasting waves may encounter more ambiguous uncertainties in the coastal or harbor area due to the influence of complicated geometric configurations. Thus this paper attempts to forecast the waves based on learning the characteristics of observed waves, rather than the use of the wind information. This is reported in this paper by the application of the artificial neural network (ANN), in which the back-propagation algorithm is employed in the learning process for obtaining the desired results. This model evaluated the interconnection weights among multi-stations based on the previous short-term data, from which a time series of waves at a station can be generated for forecasting or data supplement based on using the neighbor stations data. Field data are used for testing the applicability of the ANN model. The results show that the ANN model performs well for both wave forecasting and data supplement when using a short-term observed wave data.  相似文献   

悬浮沙激光散斑图像处理的研究     

杜军兰  陈靖齐  于连生  刘海坤  徐雷 《海洋技术学报》2001,20(1):107-111

本文以统计模式识别为基础，阐述了图像处理在悬浮沙粒粒径流量中的实际应用，提出了用图像层析来确定放大系数的方法，提出了测量的准确度。  相似文献   

走航测深数据的自动采集     

陈汉权  蔡淇松  林民森 《热带海洋学报》1991,(4)

本文介绍应用IBM微机实现走航实时水深及定位数据的自动采集系统。给出了联机系统方框图及采集、传送数据的程序流程图。并对IBM-PC/XT微机与测深仪之间的接口、数码转换和数据处理作了简要的叙述。  相似文献   

Data assimilation for a coastal area morphodynamic model: Morecambe Bay     

T.R. Scott  D.C. Mason 《Coastal Engineering》2007

This paper investigates the use of data assimilation in coastal area morphodynamic modelling using Morecambe Bay as a study site. A simple model of the bay has been enhanced with a data assimilation scheme to better predict large-scale changes in bathymetry observed in the bay over a 3-year period. The 2DH decoupled morphodynamic model developed for the work is described, as is the optimal interpolation scheme used to assimilate waterline observations into the model run. Each waterline was acquired from a SAR satellite image and is essentially a contour of the bathymetry at some level within the inter-tidal zone of the bay. For model parameters calibrated against validation observations, model performance is good, even without data assimilation. However the use of data assimilation successfully compensates for a particular failing of the model, and helps to keep the model bathymetry on track. It also improves the ability of the model to predict future bathymetry. Although the benefits of data assimilation are demonstrated using waterline observations, any observations of morphology could potentially be used. These results suggest that data assimilation should be considered for use in future coastal area morphodynamic models.  相似文献   

自动海洋站数据接收与处理软件的功能及特点     

彭伟  张翼飞 《海洋技术学报》2001,20(1):62-64

采集设备采集数据发送到值班PC机，在无人干预的情况下接收处理软件自动对数据进行回放和进一步处理，为用户提供数据产品和服务，并提供一个界面，使用户能够了解系统的运行状况，获得相关数据和状态参数。  相似文献