支持向量机在海洋随机资料分析中的应用     

付晓  王晓燕  张海波  刘雷 《海洋技术学报》2008,27(1):89-91

在随机海洋资料的分析中,需要从大量的实际数据中提取出有用的信息来建立或检验各种海洋理论模型,因此我们要正确运用适当的手段来分析处理各种实际数据。文中简要介绍了数据挖掘中一项新的技术支持向量机,着重介绍了最优化问题的求解算法,以及如何应用于海洋资料的分析处理。  相似文献   

一种适合海洋环境温度测量的新方法   总被引：2，自引：0，他引：2  

井彦明  王景青  申秀花  刘连君 《海洋技术学报》2008,27(2):18-24

介绍了一种崭新的海洋环境温度测量方法,也可以说是一种崭新的温度测量传感器。它直接输出温度数字量,连接PC机极为方便。文中介绍了该方法的测量原理和特点;介绍了室内和海上的试验情况,给出了试验数据和曲线;展望了广阔的应用前景。  相似文献   

基于声波探测海底浅层沉积物特性的方法研究   总被引：1，自引：0，他引：1  

吴锦虹  吴百海  刘强  曾洁莹  邹大鹏 《海洋工程》2008,26(1):114-119

利用声波在水中的传输特性进行海底浅层沉积物特性的探测。在实践应用中有实验室方法、现场测量方法和海底声学遥测方法,并研制出大量的仪器。由于海上和海底实际条件的限制,声波探测方法都存在一定的不足之处,由此提出了声衰减测试沉积物特性以及建立实验室模拟海底环境探测方法的设想。  相似文献   

方向分布对三维聚焦波浪波面特性影响研究     

李金宣  柳淑学  孙一艳  HONG Keyyong 《海洋工程》2008,26(2):26-33

波浪聚焦被认为是产生极限波浪的重要机理之一,近年来受到普遍重视。通过高阶谱方法,引入造波边界建立数值计算模型,模拟聚焦波浪在不同方向分布时的产生和聚焦过程,研究波浪的方向分布对聚焦波浪的波面、波峰最大值、聚焦点的偏移、波面参数及频谱的影响。研究结果表明波浪方向分布越窄,波浪的非线性影响越强、波面越陡,波峰值、聚焦点的偏移和波面特征参数都越大;同时方向分布对波浪聚焦前后的能量具有很大的影响。  相似文献   

强潮河口三维无结构网格盐度数学模型   总被引：3，自引：0，他引：3  

王志力  陆永军  左利钦 《海洋工程》2008,26(2):43-53

采用平面无结构网格和垂向直接分层,建立了强潮河口盐度三维斜压力数学模型。无结构网格使模型能够适应河口复杂的边界,并可以根据需要进行局部加密。Casulli的半隐式法离散模型水位梯度和垂项紊动扩散项,克服了水位梯度和垂项紊动扩散对模型稳定性的影响,Semi-Lagrangian法用于模型对流项的离散,使模型具有"无条件"稳定性。采用水池风生流和盐度异重流算例检验了模型,并应用模型模拟了强潮河口(瓯江口)的潮流盐度运动,计算和实测结果进行比较,表明该模型是准确、可靠的。  相似文献   

基于杨赤中插值法的坡度、坡向计算的实现与分析          下载免费PDF全文

夏元平  陈天伟  张佃友 《海洋测绘》2008,28(1):9-12

应用杨赤中滤波推估法,将地形碎部点高程观测值看作一种包含规律性和随机性变化的复合变量,求其二项系数加权游动平均,建立估值数学模型,求得各格网点高程估值。将离散的数据经插值计算转换为DEM数据,并根据其网格顶点来分析、推算和显示网格单元的坡度和坡向。  相似文献   

基坑及周边建筑物变形监测方案   总被引：1，自引：0，他引：1  

冯文辰  刘欣  王永跃  刘绪广 《测绘与空间地理信息》2009,32(1)

结合某基坑变形监测项目,从观测墩及觇牌的设计、观测方法、精度估计等方面对基坑水平位移观测进行了介绍,并介绍了利用差异沉降量推算法进行倾斜观测的方法.  相似文献   

数码相机检验中出现的问题及解决方法   总被引：1，自引：0，他引：1  

郑炎兵  区意金 《地理空间信息》2009,7(3):161-164

数码相机的检验是近景摄影测量中经常碰到的问题。最常用的主要还是基于共线方程的后方交会法。但由于普通数码相机存在较大的镜头畸变,内方位元素也未知,所以仅用单片进行后方交会求取有关参数时,法方程可能会出现病态现象,从而影响最后的检验结果。文中对此现象进行了讨论,并给出了一些实用的解决方法。  相似文献   

Detection of nighttime sea fog/stratus over the Huanghai Sea using MTSAT-1R IR data   总被引：2，自引：0，他引：2  

GAO Shanhong  WU Wei  ZHU Leilei  FU Gang  HUANG Bin 《海洋学报(英文版)》2009,28(2):23-35

A dual channel difference (DCD) method is applied to detect nighttime sea fog/stratus over the Huanghai Sea using the infrared (IR) data of shortwave (3.5–4.0 μm) and longwave (10.3–11.3 μm) channels from the Multi-functional Transport Satellite (MTSAT)-1R, i.e., shortwave minus longwave brightness temperature difference (SLTD). Twenty-four sea fog events over the Huanghai Sea during March to July of 2006 and 2007 are chosen to determine a suitable value of SLTD for nighttime sea fog/stratus detection, and ...  相似文献   

Winkler's method overestimates dissolved oxygen in seawater: Iodate interference and its oceanographic implications     

George T.F. Wong  Kuo-Yuan Li 《Marine Chemistry》2009,115(1-2):86-91

Dissolved oxygen in seawater has been determined by using the Winkler's reaction scheme for decades. An interference in this reaction scheme that has been heretofore overlooked is the presence of naturally occurring iodate in seawater. Each mole of iodate can result in an apparent presence of 1.5 mol of dissolved oxygen. At the concentrations of iodate in the surface and deep open ocean, it can lead to an overestimation of 0.52 ± 0.15 and 0.63 ± 0.05 μmol kg^− 1 of oxygen in these waters respectively. In coastal and inshore waters, the effect is less predictable as the concentration of iodate is more variable. The solubility of oxygen in seawater was likely overestimated in data sources that were based on the Winkler's reaction scheme for the determination of oxygen. The solubility equation of García and Gordon [Garcia H.E., Gordon, L.I., 1992. Oxygen solubility in seawater: Better fitting equations. Limnol. Oceanogr. 37, 1307–1312] derived from the results of Benson and Krause [Benson, F.B., Krause, D. Jr., 1984. The concentration and isotopic fractionation of oxygen dissolved in freshwater and seawater in equilibrium with the atmosphere. Limnol. Oceanogr. 29, 620–632] is free from this source of error and is recommended for general use. By neglecting the presence of iodate, the average global super-saturation of oxygen in the surface oceans and the corresponding efflux of oxygen to the atmosphere both have been overestimated by about 8%. Regionally, in areas where the degree of super-saturation or under-saturation of oxygen in the surface water is small, such as in the tropical oceans, the net air–sea exchange flux can be grossly under- or overestimated. Even the estimated direction of the exchange can be reversed. Furthermore, the presence of iodate can lead to an overestimation of the saturation anomaly of oxygen in the upper ocean attributed to biological production by 0.23 ± 0.07%. AOU may have been underestimated by 0.52 ± 0.15 and 0.63 ± 0.05 μmol kg^− 1 in the surface mixed layer and deep water, while preformed phosphate and preformed nitrate may have been overestimated by 0.004 ± 0.001 and 0.06 ± 0.02 μmol kg^− 1 in the surface mixed layer, and 0.005 ± 0.0004 and 0.073 ± 0.006 μmol kg^− 1 in the deep water. These are small but not negligible corrections, especially in areas where the values of these parameters are small. At the increasing level of sophistication in the interpretation of oxygen data, this source of error should now be taken into account. Nevertheless, in order to avoid confusion, an internationally accepted standard needs to be adopted before these corrections can be applied.  相似文献