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21.
The upper layer (above 140 m depth) temperature in the western Philippine Sea near Taiwan was sampled using a coastal monitoring
buoy (CMB) with 15 attached thermistors during July 28–August 7, 2005. The data were collected every 10 min at 1, 3, 5, 10,
15, and 20 m using the CMB sensors, and every 15 sec at 15 different depths between 25 m and 140 m. Internal waves and solitons
were identified from the time-depth plot of the temperature field. Without the internal waves and solitons, the power spectra,
structure functions, and singular measures (representing the intermittency) of temperature field satisfy the power law with
multi-scale characteristics at all depths. The internal waves do not change the basic characteristics of the multifractal
structure. However, the internal solitons change the power exponent of the power spectra drastically, especially in the low
wave number domain; they also break down the power law of the structure function and increase the intermittency parameter.
The physical mechanisms causing these different effects need to be explored further. 相似文献
22.
风力对内陆浅水水域磷水平的影响 总被引:1,自引:0,他引:1
本文通过对平度市大泽山水库(面积约0.5平方公里,平均水深约1.5米)的实地观测,研究了风力对内陆浅水水域磷水平的影响。结果表明,影响程度取决于风速、风力作用时间、水深以及风力作用前磷水平的高低等因素。就大泽山水库而言,风速大于2.5米/秒的风力可引起各种形态磷的明显增加。不过对磷酸盐磷来说,如果浓度本来就较高,风力作用下当有大量沉积物颗粒泛起时,会对PO_4~≡产生吸附,因而可能导致水中游离磷酸盐磷含量下降。鉴于此,作者建议对内陆浅水水域进行磷水平调查时应考虑风力的作用。 相似文献
23.
24.
采用新极谱技术(1.5次微分)的阳极溶出伏安滴定方法测定天然海水的铜络合容量和条件稳定常数。对测试条件、EDTA回收率和有关问题进行了探讨。青岛近岸水样的九次平行测定表明,铜的表现络合容量为3.01×10~(-7)mol/dm~3,条件稳定常数为7.34×10~7,相对标准偏差分别为9.2%和13.8%。 相似文献
25.
Marco Ortiz 《Marine Ecology》2002,23(1):1-9
Abstract. The current article describes statistical power analysis as an efficient strategy for the estimation of the optimum sample size. The principle aim is constructively to criticise and enrich the results presented by Mouillot et al. (1999) , who estimate the optimum sample size for evaluating possible perturbations. The authors did not make any reference to statistical power analysis, even though their objective clearly went beyond a simple stock evaluation to assess management strategies in a particular marine ecosystem. Surprisingly, they proposed (a priori) an ANOVA design to test a hypothesis considering both space and temporal scales. However, the authors did not cover important topics related with power analysis and the precautionary principle, both used into environment impact assessment programmes for marine ecosystems. Based on their results and on statistical power analysis, it is demonstrated that the variability (dispersion statistics), a key factor they used to estimate the sample size, is less relevant than the magnitude of perturbation (effect size). Therefore, a greater effort must be devoted to estimate the effect size of a particular phenomenon rather than a desired variability. 相似文献
26.
研究外荷载为长期非平稳随机过程。考虑长期荷载的特性 ,采用 1个概率谱密度函数来反映长期非平稳随机荷载及其特征 ;概率谱密度函数是基于大量的一般谱密度函数的统计特性获得。以延长结构的抗疲劳使用寿命为目标函数 ,提出了调谐质量减振阻尼器的优化设计方法 ,这在实际工程中有着极为广阔的应用前景。本文旨在从理论上发展长期非平稳随机荷载作用下调谐质量减振阻尼器的优化设计方法 ;文中采用长期波浪实测数据 ,给出了 1个数值算例说明整个设计过程。 相似文献
27.
Sequence variation of the first internal transcribed spacer of ribosomal DNA ( ITS - 1 ) was examined and its application to the study of genetic variation was explored in four populations of farter' s scallop Chlamys farreri. ITS - 1 fragments, with a length of about 300 bp,of 78 individuals collected from Dalian, Qingdao, Yantai in China and Korea respectively were amplified via PCR, cloned and sequenced. Intra-genomic variation was examined by sequencing several clones of single individuals. Alignment and polymorphism analysis detected 44 haplotypes and 50 polymorphic sites which consist of 30 substitutions and 20 indels, indicating a high level of polymorphisms. Sequence analysis also showed a very low level of intra-individual variation. All these features validated the feasibility of application of ITS - 1 fragment to population analysis. Polymorphism analysis showed that the Korea sample has the richest genetic variation, followed by Yantai and Qingdao samples. AMOVA (analysis of molecular variance) showed that the majority (96.26%) of genetic variation was distributed within populations and 3.74% resulted from among populations, but with P 〈 0.05 ( = 0.042), indicating that the populations in this study have significant divergence. This output was basically concordant with the result arising from RAPD data and different from that from mitochondrial 16S rDNA sequence data. Discussion on this inconsistency was made accordingly. 相似文献
28.
给出了提取潮汐调和常数的一种新方法--正交方法,并应用1992~1997年的TOPEX/POSEIDON卫星高度计遥感资料,提取中国海M2分潮调和常数.同时,利用最小二乘法来提取中国海M2分潮调和常数,两种方法结果比较渤海、黄海、东海海域M2分潮振幅、迟角的均方差分别是3.3 cm,3.6°;南中国海海域M2分潮振幅、迟角均方差分别是1.1 cm,1.7°,结果表明正交方法是一种可信的具有实用性的方法. 相似文献
29.
30.
This paper deals with the infrared spectra of " amino acid- clay , calcium carbonate and y-AlOOH" and " Cu (II )-clay-amino acid" model systems, and shows that the model of the ternary surface complex is M-OHLCu (L = amino acid) for marine solid particle-Cu (II)-amino acid. Study of the formation mechanism of the ternary surface complex shows that the specific surface area , and especially the intrinsic acidity constant, determine whether the ternary surface complex is easily formed, and that factor, FTSC,quantifies the relationship between the promoting effect of organics on Mt-marine solid particle ion exchange and the intrinsic acidity constant and specific surface area. 相似文献