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1.
In this paper, the principle and steps for differentiating water masses by fuzzy cluster method are introduced, and a scalar formula bsed on Euclidean distance and a method for determining objectively the number of water masses by F-test are proposed. Consequently, a method and specific steps for differentiating modified water masses in shallow sea according to fuzzy elastic classification are given. Computation of the membership degree in which each sample belongs to every water mass determines conveniently and quantitatively the cores, boundaries of water masses and mixed zones. An example for the Huanghai Sea and East China Sea is shown and compared with previous results. 相似文献
2.
用模糊集合观点讨论水团的有关概念 总被引：1，自引：0，他引：1
本文将划分水团的基本原则,概括为水团内部特征的相对均一性及其与外部海水的明显差异性。用模糊集合讨论了水型、水团和水系等有关概念。提出了用模糊集合观点定义水团及其核心、本体、边界与混合区的建议,并以1979年8月黄海和东海表层为例,给出了各水团的隶属函数。计算了其核心、本体、边界、混合区及贴近度,按其模糊性排出了顺序。 相似文献
3.
The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The conceptions of water type, water mass and water system are dealt with on the basis of the theory of fuzzy sets. A proposal to apply the theory of fuzzy sets to define the water mass and its core, independent area, boundary and mixing area is put forward.As an example, the membership function of the surface water masses in the Yellow Sea and East China Sea in August, 1979, are considered. Their cores, independent areas, boundaries, mixing areas and the approximation degrees between different water masses are calculated respectively. The water masses are ranged according to their fuzzy degrees. 相似文献
4.
5.
Application of method of fuzzy sets to the analysis of water masses in the northern South China Sea 总被引：3，自引：1，他引：3
Some methods of fuzzy sels are applied to the analysis of water masses in the north area of the South China Sea. In distinguishing water masses with the fuzzy clustering method, the authors propose a fuzzy similar relation based on Euclidean distance, and suggest a method for determining the number of water masses by the F-test, and further adjust rationally the boundaries of water masses and the membership relation of samples by the elastic classification method. Eight water masses are distinguished in the area, i.e., Nearshore Diluted Water F, Nearshore Mixed Water M, Warm Surface Water WS, Surface Water S, Surface-Subsurface Mixed Water SU, Subsurface Water U, Subsurface-Intermediate Mixed Water UI and Intermediate Water I. These point-sets of various water masseson the (?)-S diagram may be summed up in three types, that is, the deformed elliptical convexpoint-set, the half-boundless convex point-set and the point-set with single-side concave. For them, we have proposed methods of making their member 相似文献
6.
使用1987年5～6月黄、东海的调查资料,在水团多元模糊划分的基础上,引入了使用隶属函数的模糊判别分析,对海域中的11个水团模糊划分的有效性,给出了合理的判别方法,使水团的模糊分析增添了新的内容,得到了一些有益的结论。同时,简要地分析了各水团的分布与特征。 相似文献
7.
On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made by using the method of fuzzy cluster from the modified characteristic of water masses in the shallow water area. In this paper, the basic features, growth and decline patterns of water masses in relation to fishing grounds in the whole shelves of the Bohai Sea, the Huanghai Sea and the East China Sea are discussed with emphasis. 相似文献
8.
黄、东海域春季水团的模糊分析 总被引：2，自引：2，他引：2
本文对黄、东海毗连海域1987年春季的水团,用模糊数学方法进行了系统的分析。在聚类分析和判别分析的基础上,对各水团的点集进行必要的处理,分别建立它们的隶属函数。根据隶属度的分析,用图示给出各水团的核心、本体和边界。本文还计算了各水团的熵以及水团之间的贴近度。据此划分水系,分析它们之间的逐级变性与相互关系,取得了满意的结论。 相似文献
9.
变性水团软划分的一种FUZZY模式 总被引：1，自引：0，他引：1
在已知研究海区水团核心的前提下,考虑到各种指标对标识水团的不同贡献,提出了一种水团软划分的FUZZY模式。利用1987年5—6月黄东海的温、盐和溶解氧实测资料进行计算,与已有成果作了对比,结果令人满意。 相似文献
10.
The idea of modified water masses is introduced and a cluster analysis is used for determining the boundary of modified water masses and its variety in the shallow water area of the Huanghai Sea (Yellow Sea) and the East China Sea. According to the specified standards to make the cluster, we have determined the number and boundary of the water masses and the mixed zones.The results obtained by the cluster method show that there are eight modified water masses in this area. According to the relative index of temperature and salinity,the modified water masses are divided into nine different characteristic parts. The water, masses may also be divided into three salinity types. On the TS-Diagram, the points concerning temperature and safinity of different modified mater masses are distributed around a curve, from which the characteristics of gradual modification may be embodied. The variation ranges of different modified water masses are all large, explaining the intensive modification of water masses in th 相似文献
11.
1998年夏、冬季南海水团分析 总被引：15，自引：2，他引：15
为了解南海水团的特征和分布 ,基于 1 998年夏季和冬季两个航次的实测资料 ,采用聚类分析、判别分析和模糊分析方法 ,对南海的水团进行了分析。结果表明 ,南海外海水可划分为 6个水团 ,即南海表层水团、南海次表层水团、南海次 中层混合水团、南海中层水团、南海深层水团和南海底盆水。越南附近夏季存在一个暖涡 ;1 998年夏季还可鉴别出黑潮表层水团和黑潮次表层水团 ,但在冬季观测期间无黑潮水越过 1 1 9.5°E经线进入南海 ;这些现象可能与厄尔尼诺现象有关联。夏季有苏禄海海水在 5 0— 75m层经由民都洛海峡侵入南海 相似文献
12.
提出不受资料输入顺序影响的模糊密度聚类法。给出模糊点密度的定义与计算方法,并用渤、黄、东海的温盐资料,进行模糊密度聚类计算,对聚类结果及水团划分进行了讨论。 相似文献
13.
舟山渔场及其邻近海域水团的季节特征 总被引：5，自引：0，他引：5
根据2001年夏季和2002年冬季两次现场调查所收集的CTD和营养盐资料,利用模糊聚类分析法,对舟山渔场及其邻近海域水团的季节特征进行了分析.结果表明,舟山渔场及其邻近海域水团的配置、分布范围、温盐特性和营养盐含量都有明显的季节特征.其中,冬季在全海域共有3个水团(江浙沿岸水、台湾暖流表层水和黄海混合水),而夏季则存在4个水团(江浙沿岸水、台湾暖流表层水、台湾暖流深层水和黄海混合水);冬季,江浙沿岸水的分布范围较小,温度偏低,盐度略高,营养盐偏高,而夏季,其分布范围较大,温度偏高,盐度偏低,营养盐偏低;冬季,台湾暖流表层水北伸最强,厚度最厚,温度最低,盐度最高,硅酸盐和硝酸盐偏高,而夏季,则北伸最弱,厚度最薄,温度最高,盐度最低,硅酸盐和硝酸盐偏低;台湾暖流深层水是一个季节性水团,它含有较丰富的营养盐;黄海混合水的分布范围和营养盐含量也都呈现出明显的季节特征. 相似文献
14.
Water masses in the subsurface and the intermediate layer are actively formed due to strong winter convection in the Japan
Sea. It is probable that some fraction of pollution is carried into the layer below the sea surface together with these water
masses, so it is important to estimate the formation rate and turnover time of water masses to study the fate of pollutants.
The present study estimates the annual formation rate and the turnover time of water masses using a three-dimensional ocean
circulation model and a particle chasing method. The total annual formation rate of water masses below the sea surface amounted
to about 3.53 ± 0.55 Sv in the Japan Sea. Regarding representative intermediate water masses, the annual formation rate of
the Upper portion of the Japan Sea Proper Water (UJSPW) and the Japan Sea Intermediate Water (JSIW) were estimated to be about
0.38 ± 0.11 and 1.43 ± 0.16 Sv, respectively, although there was little evidence of the formation of deeper water masses below
a depth of about 1500 m in a numerical experiment. An estimate of turnover time shows that the UJSPW and the JSIW circulate
in the intermediate layer of the Japan Sea with timescales of about 22.1 and 2.2 years, respectively. 相似文献
15.
黄、东海域春季水团的划分、判别与分析 总被引：5，自引：0，他引：5
本文对黄、东海邻接海域5—6月份的水团进行了划分和分析。水团的划分是用经过改进的逐步聚类分析法。对划分的结果,再用Bayes多组判别方法进行判别分析检验。证实所划出的11个水团,具有统计学要求的差异显著性,回代判别成效高达90％以上,说明划分是有实际意义的。这11个水团是:沿岸冲淡水(D),黄海表层水(Y),黄海底层冷水(YC),黄—东海混合水(YE),东海表层水(E),东海次表层水(EU),黑潮表层水(KS),黑潮次表层水(KU),黑潮次—中层混合水(KM),黑潮中层水(KI)和黑潮深层水(KD)。 用地理学和统计学的方法,对各水团进行了综合分析。给出了各水团特征的统计指标,讨论了它们的形成机制与分布变化特点。可将它们归并为三个水系:冲淡水系;混合水系和黑潮水系。对各水系、水团之间的相互关系进行了讨论,指出它们具有逐级变性的明显的规律性。 相似文献
16.
南海北部海区水团分析 总被引：1，自引：0，他引：1
以模糊聚类为主要方法,在南海北部海区划出8个水团:沿岸冲淡水团(F)、近岸混合水团(M)、暖表层水团(WS)、表层水团(S)、表-次层混合水团(SU)、次层水团(U)、次-中层混合水团(UI)和中层水团(I).对各水团的形成、基本特征、变性特点以及消长变化和分布规律进行了综合分析.可将它们分为3种类型:径流冲淡型——F,浅海变性型——M、WS、S、SU和深海大洋型——U、UI和I. 相似文献
17.
The waters in the shallow part of the Yellow Sea and East China Sea are affected greatly by climatic and geographical conditions and fail to possess homogeneity and conservativeness like oceanic waters. They have apparent difference in modified degrees, so we may regard a certain range of mixed water as a relatively independent one. In fact, the study of water masses in the shallow sea means a modified analysis of waters. The idea of modified water masses is introduced, i. e., a water body which holds the similar physical and chemical characters, occupies a certain space, and varies seasonally and regularly. On the T-S diagram, it displays as a certain amount of points aggregated together, the centre of which changes regularly and may have a process of combination and separation.According to the clustering method, there are eight modified water masses in this area. They may also be divided into three salinity types. On the T-S diagram, the points concerning temperature and salinity of different modified 相似文献
18.
李福荣 《中国海洋大学学报(自然科学版)》1995,(2)
以１９８７年５—６月中日台作黄东海域综合调查的溶解氧资料为主，探讨调查海区溶解氧分布特征与水团的对应关系。指出：近岸水团溶解氧合量高，远海低；上层水团高，下层低。在黄海冷水和东海北部底层冷水的上界出现明显的溶解氧垂直分布最大值及封闭形高氧区。水团边界区，氧跃层明显。溶解氧含量变化与水团温盐特性有关。通过分析发现，溶解氧对鉴别次表层以深各水团，特别对鉴别东海次表层水及黑潮次表层以深各水团，可作为一种有效的指标。 相似文献
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20.
Monthly Variations of Water Masses in the Yellow and East China Seas, November 6, 1998 总被引：4，自引：0，他引：4
The monthly water mass variations in the Yellow Sea and the East China Sea are investigated using over 40 years of historical
temperature and salinity observations via a cluster analysis that incorporates geographical distance and depth separation
in addition to the temperature and salinity. Results delineate monthly variations in the major water masses and provide some
insight into formation mechanisms and intermixing. The major water masses include the Kuroshio-East China Sea water (KE),
the Yellow Sea surface water (YSS) and bottom cold water (YSB), mixed water (MW), and coastal water (CW). The distribution
of the KE water mass reveals the intrusion pattern into the area west of Cheju. A separate mixed water type appears between
the KE water mass and the Yellow Sea water masses during winter. The formation mechanism of the YSB appears to be the surface
cooling and active mixing in winter. In the East China Sea, during summer, surface water is differentiated from the subsurface
water while there is no differentiation during winter. In the Yellow Sea, a three layer system exists in the summer and fall
(May–November) while a two layer system exists during the rest of the year. A fresh water mass generated by Yangtze River
discharge (YD) is present over the northern East China Sea and the southern Yellow Sea during summer.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献