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1.
多元指标的海上溢油信息提取 总被引：1，自引：0，他引：1
海上溢油给海洋生态环境带来了巨大的影响,甚至需要几十年才能恢复。运用卫星遥感进行海上溢油监测已成为目前溢油监测的主要手段。本文对海上溢油遥感监测方法进行了分析,鉴此,提出了一种SAR数据的多元指标溢油信息提取方法。首先,对图像进行分割,然后,建立溢油形状参数、纹理特征指数、物理特性指数等主要指标,并以层次分析法得出每一类指标的权重。针对每一类指标,以经现场验证的溢油图像为基础,选择形状参数,如周长与面积比值、复杂度等,建立溢油形状判读等级;选择纹理特征参数,以灰度共生矩阵的相关性、熵、变化等来表达溢油的纹理特性,建立溢油纹理特征判断等级;选择溢油物理特征,如溢油与海水的标准差、均方根差、对比度等,建立溢油物理参数判断等级。在此基础上,建立海上溢油遥感信息提取指数,计算分割图斑的溢油遥感信息提取指数,以此判断溢油遥感信息提取的置信度,为溢油识别提供依据。 相似文献
2.
海面溢油对生态环境造成了严重危害,故及早发现和尽快处理对降低事故影响和经济损失起着至关重要的作用。合成孔径雷达(SAR)是观测海面溢油、快速检测和事故态势分析判断的有效技术途径。本文针对SAR图像的海面溢油检测,提出了一种特征概率函数的双阈值分割方法。首先,通过高低阈值分割提取不同层次的灰度信息,再利用密度估计提取灰度的空间分布信息,然后,通过构建概率函数对油膜和类油膜区域进行形态学分类,最后,结合辅助信息,获得最终的海面溢油检测结果。本文利用香港中文大学卫星地面站接收的ENVISAT ASAR图像开展实验,结果表明,本文提出的方法能够准确地排除由风场或者水流场导致的低散射区域,有效地检测和识别生成不久的中型油膜,从而有助于溢油事故的早期预警与处置。 相似文献
3.
随着海上石油运输业和海洋石油工业的迅速发展,海上溢油事故频繁发生,造成了巨大的生态和经济上的损失,因此,实时监测溢油信息对灾害防控具有重要意义。本文基于多源SAR影像数据,开展了溢油遥感监测研究,构建了基于GIS的海洋溢油业务化监测系统。系统基于GDAL对原始数据进行解析,实现影像输入和几何校正等处理;在此基础上,封装多尺度图像分割算法和灰度对比度特征提取算法,对SAR影像数据进行分块、分割、溢油识别、合并及参数赋值等自动化处理,实现溢油信息提取的一键化处理;面向溢油监测应用需求,制作各类标准化产品,自动添加制图整饰要素、影像参数、溢油面积和溢油源等各类信息,并实时生成专题快报。 相似文献
4.
Journal of Oceanology and Limnology - Features of oil spills and look-alikes in polarimetric synthetic aperture radar (SAR) images always play an important role in oil spill detection. Many oil... 相似文献
5.
The estimation of oil spill coverage is an important part of monitoring of oil spills at sea.The spatial resolution of images collected by airborne hyper-spectral remote sensing limits both the detection of oil spills and the accuracy of estimates of their size.We consider at-sea oil spills with zonal distribution in this paper and improve the traditional independent component analysis algorithm.For each independent component we added two constraint conditions:non-negativity and constant sum.We use priority weighting by higher-order statistics,and then the spectral angle match method to overcome the order nondeterminacy.By these steps,endmembers can be extracted and abundance quantified simultaneously.To examine the coverage of a real oil spill and correct our estimate,a simulation experiment and a real experiment were designed using the algorithm described above.The result indicated that,for the simulation data,the abundance estimation error is 2.52% and minimum root mean square error of the reconstructed image is 0.030 6.We estimated the oil spill rate and area based on eight hyper-spectral remote sensing images collected by an airborne survey of Shandong Changdao in 2011.The total oil spill area was 0.224 km~2,and the oil spill rate was 22.89%.The method we demonstrate in this paper can be used for the automatic monitoring of oil spill coverage rates.It also allows the accurate estimation of the oil spill area. 相似文献
6.
利用遥感成像技术获取地面水体信息对水资源调查、自然灾害评估、流域规划和生态环境监测等具有重要意义,其中SAR成像作为大范围地面监测的可靠数据源,拥有全天时、全天候、广覆盖等光学遥感系统所不具有的优点,在水体提取中得到了广泛的应用。但由于受SAR图像相干斑噪声的影响,现有水体提取方法难以迅速、精确提取SAR图像中复杂精细的自然水体结构。为此,提出一种结合改进的降斑各向异性扩散和最大类间方差的SAR图像水体提取方法。首先,利用降斑各向异性扩散滤波SAR图像,在迭代滤波过程中通过计算图像间平均结构相似度自适应控制迭代过程,使其同时保持精细边缘和纹理结构;然后,以类间方差最大为准则,自适应确定阈值,实现滤波结果图像二值化分割。在二值化分割结果中,搜索具有相同像元值且位置相邻的前景像元点组成的连通区域,使每个单独的连通区域形成一个被标识的块,通过获取这些块的几何参数来消除图像的误分割,精确划定真实的水体区域,以实现SAR图像水体提取。为了验证提出方法的准确性,将本文方法提取的水体边界与人工绘制的水体边界叠加,结果表明二者可较好吻合。同时,从视觉、提取精度和运行时间对本文方法与目前常用3种SAR图像水体提取算法的结果进行比较分析,其中本文方法的运行时间满足实时应用的要求,提取结果的边界在2个像元评级区重叠度均达到80%,明显优于其他方法且本文方法提取结果在边界及细节信息等视觉方面也更加显著。对结果的定性及定量评价表明本文方法的优越性。 相似文献
7.
An oil spill forecast system for of fshore China was developed based on Visual C++. The oil spill forecast system includes an ocean environmental forecast model and an oil spill model. The ocean environmental forecast model was designed to include timesaving methods, and comprised a parametrical wind wave forecast model and a sea surface current forecast model. The oil spill model was based on the "particle method" and fulfi lls the prediction of oil particle behavior by considering the drifting, evaporation and emulsifi cation processes. A specifi c database was embedded into the oil spill forecast system, which contained fundamental information, such as the properties of oil, reserve of emergency equipment and distribution of marine petroleum platform. The oil spill forecast system was successfully applied as part of an oil spill emergency exercise, and provides an operational service in the Research and Development Center for Off shore Oil Safety and Environmental Technology. 相似文献
8.
海面溢油对海洋生态的影响具有频率高、范围广和危害大的特点。卫星遥感已成为海面溢油监测的重要手段。本文从海面油膜光谱特性出发,与常用的光学卫星传感器建立对应关系,根据对不同光学遥感卫星的空间分辨率、时间分辨率、幅宽和波段数等主要物理参数的对比分析认为,MODIS传感器和HJ-1卫星有较强的海面溢油监测能力。故此,采用MODIS、BJ-1、HJ-1和FY-3光学卫星影像,对2006年3月和2011年6月渤海海面溢油污染事故进行了遥感监测。MODIS遥感图像可以清晰反映出2006年和2011年这2次溢油污染事故中海面油膜信息,HJ-1卫星遥感影像则能反映出2011年溢油污染事故中海面油膜信息,而BJ-1和FY-3卫星遥感影像不能反映出海面油膜信息。HJ-1、BJ-1和FY-3卫星在波段设置上相似,但是,BJ-1和FY-3卫星不能反映出油膜信息,所以,本文进一步对这2次溢油事件中的MODIS遥感影像的油水光谱反差和海水光谱方差进行计算,并对结果进行比较分析,实验结果表明,当MODIS某一波段的海水光谱方差小于油水光谱反差时,则该波段可以显示出油膜信息;而当油水光谱反差小于或接近海水方差时,则不能反映出海面油膜信息。从波谱响应、空间分辨率和时间分辨率,以及监测实例中说明MODIS传感器有较强的海面溢油监测能力。 相似文献
9.
《中国海洋湖沼学报》2019,(6)
Efficient and accurate access to coastal land cover information is of great significance for marine disaster prevention and mitigation. Although the popular and common sensors of land resource satellites provide free and valuable images to map the land cover, coastal areas often encounter significant cloud cover, especially in tropical areas, which makes the classification in those areas non-ideal. To solve this problem, we proposed a framework of combining medium-resolution optical images and synthetic aperture radar(SAR) data with the recently popular object-based image analysis(OBIA) method and used the Landsat Operational Land Imager(OLI) and Phased Array type L-band Synthetic Aperture Radar(PALSAR) images acquired in Singapore in 2017 as a case study. We designed experiments to confirm two critical factors of this framework: one is the segmentation scale that determines the average object size, and the other is the classification feature. Accuracy assessments of the land cover indicated that the optimal segmentation scale was between 40 and 80, and the features of the combination of OLI and SAR resulted in higher accuracy than any individual features, especially in areas with cloud cover. Based on the land cover generated by this framework, we assessed the vulnerability of the marine disasters of Singapore in 2008 and 2017 and found that the high-vulnerability areas mainly located in the southeast and increased by 118.97 km2 over the past decade. To clarify the disaster response plan for different geographical environments, we classified risk based on altitude and distance from shore. The newly increased high-vulnerability regions within 4 km offshore and below 30 m above sea level are at high risk; these regions may need to focus on strengthening disaster prevention construction. This study serves as a typical example of using remote sensing techniques for the vulnerability assessment of marine disasters, especially those in cloudy coastal areas. 相似文献
10.
MEI Hong* YIN Yanjie ） Law Politics School Ocean University of China Qingdao P. R. China ） School of Engineering Arts Qingdao Technical College Qingdao P. R. China 《中国海洋大学学报(英文版)》2009,8(3):312-316
The sources of marine oil spills are mainly from accidents of marine oil tankers or freighters, marine oil-drilling platforms,
marine oil pipelines, marine oilfields, terrestrial pollution, oil-bearing atmosphere, and offshore oil production equipment.
It is concluded upon analysis that there are two main reasons for marine oil spills: (I) The motive for huge economic benefits
of oil industry owners and oil shipping agents far surpasses their sense of ecological risks. (II) Marine ecological safety
has not become the main concern of national security. Oil spills are disasters because humans spare no efforts to get economic
benefits from oil. The present paper draws another conclusion that marine ecological damage caused by oil spills can be roughly
divided into two categories: damage to marine resource value (direct value) and damage to marine ecosystem service value (indirect
value). Marine oil spills cause damage to marine biological, fishery, seawater, tourism and mineral resources to various extents,
which contributes to the lower quality and value of marine resources. 相似文献
11.
建筑物的自动提取对城市发展与规划、防灾预警等意义重大。当前的建筑物提取研究取得了很好的成果,但现有研究多把建筑提取当成语义分割问题来处理,不能区分不同的建筑个体,且在提取精度方面仍然存在提升的空间。近年来,基于多任务学习的深度学习方法已在计算机视觉领域得到广泛应用,但其在高分辨率遥感影像自动解译任务上的应用还有待进一步发展。本研究借鉴经典的实例分割算法Mask R-CNN和语义分割算法U-Net的思想,设计了一种将语义分割模块植入实例分割框架的深度神经网络结构,利用多种任务之间的信息互补性来提升模型的泛化性能。自底向上的路径增强结构缩短了低层细节信息向上传递的路径。自适应的特征池化使得实例分割网络可以充分利用多尺度信息。在多任务训练模式下完成了对遥感影像中建筑物的自动分割,并在经典的遥感影像数据集SpaceNet上对该方法进行验证。结果表明,本文提出的基于多任务学习的建筑提取方法在巴黎数据集上建筑实例分割精度达到58.8%,在喀土穆数据集上建筑实例分割精度达到60.7%,相比Mask R-CNN和U-Net提升1%~2%。 相似文献
12.
根据海上溢油试验结果，结合20a来对海上溢油事故的观察结果分析了油类入海后漂流和扩散过程。经分析认为1）海面油类漂流的速度和方向取决于风和表层海流的速度和方向，海面油类漂流的速度和方向基本符合UO=UC+ζW和D=C 相似文献
13.
尺度效应的存在使得不同地物的空间及属性尺度存在差异,不存在适合于影像中所有地物的唯一尺度。但通过影像分区,然后针对不同区域设置最优分割参数,可以有效地提高影像整体的分割精度。耕地地块分割中,对分割边界的要求较高,需要保证地块边界清晰连续,鉴于此,本文提出了一种结合影像分区及尺度估计的耕地地块提取方法。本文利用不同地物的温度反演影像来实现区域划分,根据温度数据将影像划分为不同地物类型、作物类型或作物长势不同的多个区域。接下来,分别对不同的区域影像进行分割,由于不同类型地物的固有空间空间尺度不同,所以不同区域影像的最佳分割参数也随之不同。空间统计的平均局部方差法可以用来预估各区域影像的分割参数,与分割参数优选的方法相比,该方法可快速准确定位,且效率较高。因此本文利用该方法进行参数估计,采用边缘约束分水岭分割算法进行耕地地块分割。此外,本文对现有影像分割评价指标进行了改进。实验结果显示,本文提出的耕地地块提取方法可针对影像的不同区域,快速准确地设置分割参数,且与其他分割方法相比,地块边界更清晰连续、多边界问题得到了极大改善。 相似文献
14.
Oil spill models can effectively simulate the trajectories and fate of oil slicks, which is an essential element in contingency planning and effective response strategies prepared for oil spill accidents. However, when applied to offshore areas such as the Bohai Sea, the trajectories and fate of oil slicks would be affected by time-varying factors in a regional scale, which are assumed to be constant in most of the present models. In fact, these factors in offshore regions show much more variation over time than in the deep sea, due to offshore bathymetric and climatic characteristics. In this paper, the challenge of parameterizing these offshore factors is tackled. The remote sensing data of the region are used to analyze the modification of wind-induced drift factors, and a well-suited solution is established in parameter correction mechanism for oil spill models. The novelty of the algorithm is the self-adaptive modification mechanism of the drift factors derived from the remote sensing data for the targeted sea region, in respect to empirical constants in the present models. Considering this situation, a new regional oil spill model (i4OilSpill) for the Bohai Sea is developed, which can simulate oil transformation and fate processes by Eulerian-Lagrangian methodology. The forecasting accuracy of the proposed model is proven by the validation results in the comparison between model simulation and subsequent satellite observations on the Penglai 19-3 oil spill accident. The performance of the model parameter correction mechanism is evaluated by comparing with the real spilled oil position extracted from ASAR images. 相似文献
15.
Effective and efficient SAR image segmentation has a significant role in coastal zone interpretation. In this paper, a coastal zone segmentation model is proposed based on Potts model. By introducing edge self-adaption parameter and modifying noisy data term, the proposed variational model provides a good solution for the coastal zone SAR image with common characteristics of inherent speckle noise and complicated geometrical details. However, the proposed model is difficult to solve due to to its nonlinear, non-convex and non-smooth characteristics. Followed by curve evolution theory and operator splitting method, the minimization problem is reformulated as a constrained minimization problem. A fast alternating minimization iterative scheme is designed to implement coastal zone segmentation. Finally, various two-stage and multiphase experimental results illustrate the advantage of the proposed segmentation model, and indicate the high computation efficiency of designed numerical approximation algorithm. 相似文献
16.
鉴于仅依赖光谱特征或纹理特征的传统溢油检测算法的信息检测精度较低的问题,本文提出了一种新的光学遥感数据的谱纹海面溢油检测方法。谱是光学遥感数据的油膜敏感波段图像,纹是利用灰度共生矩阵计算获得的图像纹理特征,将这些特征相结合,引入支持向量机方法（Support Vector Machine,SVM）,建立谱纹海面溢油检测模型。本文以2006年渤海溢油事故为例,利用中等分辨率成像光谱仪MODIS的光学遥感数据对溢油进行检测,MODIS的第2波段为油膜敏感波段,所以,第2波段图像即为选取的谱特征,经过对各个纹理特征的分析得到,均值、对比和相关3个特征量可作为溢油提取的纹理特征。检测结果的总体精度达91.23%。试验结果表明,将MODIS图像的光谱特征和纹理特征相结合,可有效地对渤海海洋油膜信息进行检测,并具有很强的抑制噪声能力。 相似文献
17.
传统基于光谱信息的水体提取未能考虑水体形状、纹理、大小、相邻关系等问题,且存在同物异谱、异物同谱现象,导致水体提取精度较低。而传统基于分类提取水体方法设计特征过程较为繁琐,且不能挖掘深度信息特征。因此,本文提出改进的U-Net网络语义分割方法,借鉴经典U-Net网络的解编码结构对网络进行改进：① 将VGG网络用于收缩路径以提取特征;② 在扩张路径中对低维特征信息进行加强,将收缩特征金字塔上一层的特征图与下一层对应扩张路径上的特征图进行融合,以提高提取结果分割精度;③ 在分类后处理中引入条件随机场,以将分割结果精细化。在保持相同训练集、验证集和测试集的情况下,分别用SegNet、经典U-Net网络和改进的U-Net网络做对照试验。试验结果表明,改进的U-Net网络结构在IoU、精准率和Kappa系数指标上均高于SegNet和经典U-Net网络,与SegNet相比,3项指标分别提升了10.5%、12.3%和0.14,与经典U-Net网络结果相比,各个指标分别提升了5.8%、4.4%和0.05。改进的网络水体提取结果较为完整,对小目标水体能够准确提取。改进的U-Net网络能够有效地实现水体提取任务。 相似文献
18.
To the potential oil-spill risk caused by offshore pipeline more attention has been paid after the Dalian oil spill incident from oil-pipeline explosion. Since then an issue about how to prevent and control the sudden oil-spill from the offshore pipeline has been raised. In this paper, we proposed an optimized model to analyze the main causes （probability） of spill and the consequence with the fuzzy comprehensive assessment model. Considering the complicated assessment process for oil-spill, the assessment factor system involving the spill probability and consequence was established based on the operative manual and statistic leakage/damage data of offshore pipeline in order to estimate the integrated spill risk score automatically. The evaluated factors of spill probability could be grouped into five aspects：corrosion, fatigue, national damage, third party, and operational fault;the consequence evaluated factors of spill included hazard of oil and impact-controlling capability. With some modifications based on experts’ opinions, each of the evaluated factors in our work was developed with a relative weight and evaluation criterion. A test example for an offshore pipe-line in the Bohai waters was described to show how the model can be used for an actual case in more detail. By using the oil-spill risk assessment model, it is easy to determine the risk level associated with the ongoing activity and management level and hence to take the risk mitigation action immediately. 相似文献
19.
Response of microbial community to petroleum stress and phosphate dosage in sediments of Jiaozhou Bay,China 总被引：1，自引：0，他引：1
ZHAO Yangguo CHEN Min BAI Jie LI Xinwei Farhana Zulfiqar and WANG Qianli 《中国海洋大学学报(英文版)》2014,13(2):249-256
The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation. 相似文献
20.
中文地址分词是中文地址标准化的基础工作和地理编码的重要手段,同时也是中文分词和地理研究领域中关注的热点问题之一。针对当前中文地址分词方法缺乏地址层级切分和过多依赖词典和特征的问题,本研究结合四词位标注集和中文层级地址特点,构建针对中文层级地址分词的地址标注体系,并提出融合双向长短时记忆网络和条件随机场(BiLSTM-CRF)的中文层级地址分词模型。该模型既考虑了BiLSTM模型能够记忆上下文地址的特性,也保留了CRF算法可以通过转移概率矩阵控制地址标注输出的能力。针对该地址标注体系标注的训练地址样本,分别使用CRF、LSTM、BiLSTM与BiLSTM-CRF模型进行训练对比。结果表明：① 基于中文地址标注体系的模型分词效果更佳,地址标注更为精细,符合实际地址分布情况;② BiLSTM-CRF模型精确度达到93.4%,高于CRF（90.4%）、LSTM（89.3%）和BiLSTM（91.2%）,其整体地址分词性能和各层级地址分词效果相对于其他模型更突出;③ 各模型分词性能与地址层级保持一致,即地址层级越高,分词效果越好。本研究提出的中文地址标注体系和分词模型为开展中文地址标准化工作提供了方法参考,同时也为进一步提升地理编码技术的精准度提供了可能。 相似文献