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聚类分析在海洋产业分析中的应用 总被引:1,自引:0,他引:1
聚类分析是多元统计分析中的一种方法,是将数学引入分类学形成的,比以前仅凭经验及专业知识进行分类更为科学、适用.用聚类分析方法分析研究沿海地区海洋产业状况是较高层次统计知识的运用,也是对数据挖掘技术的一种探索性研究.本文仅从产值的角度考虑地区海洋经济实力的状况,是利用聚类分析方法、借助海洋经济统计数据对地区海洋经济的实证研究. 相似文献
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海岸线的变化是一个复杂的灰色过程,了解海岸线的变化特征、变化过程和变化趋势,对促进海岸带的管理起着重要作用。针对海岸线历史数据的有限性和变化过程的灰色性,介绍了海岸线变化速率计算方法及其意义,以及灰关联分析方法的基本原理,提出了海岸线变化速率灰关联分析模式的基本步骤,分析了泉州古浮澳的海岸线变化情况。 相似文献
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为研究转子系统耦合故障特性,采用有限元方法建立了含有横向裂纹、转静碰摩的非线性转子动力学模型。首先研究了不同转速下裂纹、碰摩单一故障下转子系统的振动响应,其次研究了两种故障耦合情况下系统的振动响应特征。采用波形图、FFT谱图、瞬时频率和Hilbert-Huang时频谱(HHS)相结合的方法对故障转子振动信号进行了分析。分析结果表明:运用多种时频分析相结合的方法可以较为全面地了解转子的故障特征,裂纹转子在1/5、1/3临界转速时会发生较为明显的5X、3X谐波,且裂纹的产生会导致响应幅值增大,从而引起更为严重的碰摩。 相似文献
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以英国 OCCAM(The Ocean Circulation and Climate Advanced Modeling Project)全球环流模式的 1 994年计算结果作为初始场和边界条件 ,用 POM模式 ,对东中国海黑潮季节变化进行了数值模拟 ,特别注意了海水运动的混沌特点和质点移动轨迹。研究结果表明 :东海黑潮区地形引起的黑潮流剪切是导致混沌的主要原因 ;东海黑潮区混沌运动有明显的季节变化 ;黑潮主轴区基本是输运的屏障区。 相似文献
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We analyse the wind and wave conditions present in the Mediterranean Sea at the time and location when the cruise ship Voyager was reportedly hit by one or more big waves and suffered substantial damage. The analysis is done using wind and wave modelling supported by satellite and buoy wind and wave data. Granted the hindcast of the storm, we also analyse the local conditions for the possibility of freak waves. 相似文献
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利用径向基函数多尺度分析方法,将GOCO05S模型海洋大地水准面分解为3个尺度,并进行详细的分析统计。分解后重构的大地水准面精度达到了±0.02m,表明了径向基函数出色的多尺度分析能力。对不同深度层面上大地水准面异常的分布及成因做了深入探讨。浅层上地幔大地水准面异常主要分布于板块边缘,呈条状,与火山热点源分布类似;深层上地幔大地水准面异常和大洋中脊所在位置部分吻合,主要呈带状或块状,与上地幔的对流有关;中间层上地幔的大地水准面异常形态介于上述两者之间,主要受火山热点源和地幔对流的综合影响。 相似文献
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海王星海底长期观测系统的技术分析 总被引:3,自引:0,他引:3
美国和加拿大为建立全球最大海洋观测网而联合开展的海王星计划被誉为人类的水下“哈勃”。文中首先介绍了海王星计划的由来与背景,然后分析了其基础架构及实现的关键技术,并对我国海底观测技术的发展提出了建议。 相似文献
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A procedure to analyse triphenyltin and other organotins in fish tissues is described. The method consists of the following steps: homogenization of the fish, extraction by heating under reflux in a water/hexane mixture, centrifugation, separation of the hexane layer followed by reduction of the volume by evaporation, methylation of the organotin with a Grignard reaction, clean-up of the fish extract by column chromatography, and detection by gas chromatography with flame photometric detection. The extraction was carried out without adding acid or base to the aqueous phase, as the extraction efficiency was independent of pH. The methylation was successfully carried out in the fish extract. For clean-up of the fish extract a florisil column was used, from which the triphenylmethyltin was eluted with hexane. Using this method, triphenyltin has a recovery of 77 ± 10%, with a limit of detection of 0·8 ng/g for 0·1 g fish samples. 相似文献
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利用气象海洋数据资料和卫星遥感图片,分析研究了2005年第16号热带气旋"韦森特"(VICENTE)的特征,从最先的初始扰动到自身环流的分裂发展重组过程,以至当时周围相对应的大气环流,发现该热带气旋活动过程具有很多特性。对其移动过程进行的综合分析表明,只要存在合适距离等一定有利的条件,弱的两个涡旋之间完全可以发生强的作用力,高空辐散场的抽气作用对气旋的发展有极好的作用,所得的结论可对今后的预报提供一些启示和参考。 相似文献
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《中国海洋大学学报(自然科学版)》2015,(7)
防波堤一旦破坏,会严重影响港口的正常使用功能,准确计算防波堤的可靠度指标对港口工程意义重大。防波堤所受主要荷载为水平波浪力及波浪浮托力,计算可靠度应考虑两者的相关性。结合Gumbel-Houggard Copula函数与对数正态边缘分布构造二维的Copula分布可以很好地描述荷载间的相关性。本文以秦皇岛直立式防波堤为例,用二维Copula分布计算防波堤的可靠度,并与JC独立法、JC相关法进行了比较,结果显示:用Copula分布计算的结构可靠度指标远小于JC独立法计算结果,与JC相关法接近。 相似文献
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利用(1989年11月一1999年3月)冬季北半球500hPa候平均高度资料,分析了南沙海区冬季大风(简称为南沙冬季大风)与北半球中、高纬西风带中的超长波、长波活动的关系。结果表明:中、高纬强冷空气爆发南下是造成南沙冬季大风的最主要原因;当中、高纬的角动量输送达到一定数值后,伴随南沙海区会出现一次大风过程,在南沙冬季大风出现前期,偏高纬度的角动量有一次同步向北输送过程,使中、高纬西风增强,结果还表明:纬向扰动动能大多集中在超长波段内,经向扰动动能随纬度的不同主要集中在2—6波波段内。文中在这一基础上分析得出南沙冬季大风的预报指标. 相似文献
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分析了重力卫星数据构建的地球重力场模型EIGEN-CHAMP03S(140)、ITG-Grace2010s(180)、GO_CONS(240)、GOCO02s(250)的内符合精度,还与综合性地球重力场模型(EGM2008)进行了比较。然后,选用我国范围内854个AB级GPS/水准点,检核各模型分阶次确定的高程异常与实测值之间的差异,以体现其外符合精度。结果表明:以重力卫星数据构建地球重力场模型能以较高精度来表征重力场的中长波部分,与EGM2008模型的精度相当。在我国范围内,计算似大地水准面都能够达到米级精度,其中GOCO02s(250)模型精度最好,能达到0.5m的精度。 相似文献
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Bao Yingbin Li Runpei Gu Yongning
Ph. D. Candidate School of Naval Architecture Ocean Engineering Shanghai Jiao Tong University Shanghai Professor School of Naval Architecture Ocean Engineering Shanghai Jiao Tong University Shanghai 《中国海洋工程》1998,(1)
This paper studies intensively the problems of ship-platform collision.The ship and platformare treated as one structural system connected with spring elements and then motion equation of the colli-sion system is established.A nonlinear force-displacement relationship is derived for the simulation of lo-cal dent in a hit member and the yield surface of a dented tubular section is developed to consider the re-duction of load carrying capacity of hit members.Large deformations,plasticity and strain-hardening ofthe beam-column element are taken into account by combining the elastic large displacement analysis theo-ry with the plastic node method.The effect of the hydrodynamic forces acting on the platform,the rubberfender the property of the local dent and the buckling behavior of beam-column on collision are analyzed.The numerical simulation of the nonlinear dynamic response is carried out by Wilson θ method with updat-ed Newton-Raphson iteration.And the numerical example of the dynamic response of a offs 相似文献
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A. V. Desherevskii V. I. Zhuravlev A. N. Nikolsky A. Ya. Sidorin 《Izvestiya Atmospheric and Oceanic Physics》2017,53(8):847-858
We compare algorithms designed to extract quasiperiodic components of a signal and estimate the amplitude, phase, stability, and other characteristics of a rhythm in a sliding window in the presence of data gaps. Each algorithm relies on its own rhythm model; therefore, it is necessary to use different algorithms depending on the research objectives. The described set of algorithms and methods is implemented in the WinABD software package, which includes a time-series database management system, a powerful research complex, and an interactive data-visualization environment. 相似文献
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Abstract.
- 1) An incremental (graphical in this presentation) method for the analysis of growth curves has revealed actual, as opposed to modelled, growth rates. Here, we present data derived from the scallop Pecten maximus (L.). These actual rates exhibit differences in annual environmental conditions and differences between local populations.
- 2) Both first and second derivatives (growth rate and acceleration ? deceleration in growth rate, respectively) can be obtained from plotted size ? age data: here, size is represented by the height of the flat left valve.
- 3) The analysis of age class data from different years allows one to estimate maximum theoretical rates in any given year.
- 4) The analysis of individual data naturally reveals more than the analysis of average data, reinforcing the average nature of population growth parameters.
- 5) The departure of average data from the maxima revealed by the analysis of growth rate and acceleration allows one to identify changes in environmental conditions in different years.
- 6) The Von Bertalanffy growth curve has been used as an example because it is well known and widely used; however, any desired growth curve can be fitted by the method discussed here.