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Study on ecology of foulers on buoys in Dianbai, Guangdong, China 被引量:2
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作者 Lin Sheng, Huang Zongguo, Li Chuanyan, Zheng Chengxing and Wang JianjunThird Institute of Oceanography, Slate Oceanic Adrninistration, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期618-621,共4页
From May to July, 1985, foulers on eleven navigation buoys have been surveyed in Shuidongand Bohe Harbours of Dianbai, Guangdong. Foulers on different parts of buoys (side, bottom and in-side tail tube) were sampled. ... From May to July, 1985, foulers on eleven navigation buoys have been surveyed in Shuidongand Bohe Harbours of Dianbai, Guangdong. Foulers on different parts of buoys (side, bottom and in-side tail tube) were sampled. The thickness and cover area of foulers were measured in the field andall the foulers on an area of 30×30 cm~2 were taken back for lab. identification. Thirty-four quatita-tive samples and several qualitative samples have been got and five hundred and twenty-four sampleshave been classified. 展开更多
关键词 GUANGDONG Study on ecology of foulers on buoys in Dianbai China
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Effect of Fouling on Feeding, Oxygen Consumption and Waste Excretion of Pearl Oyster Pinctada martensii in Daya Bay Cultivation 被引量:3
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作者 苏振霞 严岩 黄良民 《Marine Science Bulletin》 CAS 2007年第2期34-42,共9页
Biofouling is a particular problem in the pearl oyster culture. It may reduce the growth and survival rates of the cultured species. Foulers are often themselves filter feeders, and are therefore potential competitors... Biofouling is a particular problem in the pearl oyster culture. It may reduce the growth and survival rates of the cultured species. Foulers are often themselves filter feeders, and are therefore potential competitors for food resource with the cultured species. Fouling organisms may also reduce the oxygen supply. A study was conducted to measure the impact of foulers on feeding oxygen consumption, and waste excretion. POM, ammonia, phosphate and oxygen concentration were measured in various treatments (cultured species, foulers). This study showed that fouling organisms had significant effect on food uptake, oxygen consumption and waste excretion. The clearance rate, ammonia and phosphate release rate, oxygen consumption rate of the fouled pearl oyster were greater than those of the clean pearl oysters. Other foulers that settled on cages or buoys also contributed much to phytoplankton depletion, oxygen consumption and concentration increase of ammonia and phosphate in water. Therefore, this study showed us that foulers were important competitors in the pearl oyster cultivation of Daya Bay in November 2005. 展开更多
关键词 pearl oyster fouler oxygen consumption rate clearance rate ammonia excretion rate phosphate excretion rate
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阈值曲线法在PD在线监测中的应用 被引量:3
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作者 王哲 蔡惟铮 +1 位作者 陈学允 王立欣 《高电压技术》 EI CAS CSCD 北大核心 1999年第2期37-39,共3页
在局部放电在线监测中抑制载波通讯干扰研究中,引入竞争学习网络的“自激励,邻抑制”作用,提出了一种基于FFT和ANN的新数字滤波方法。仿真实验和现场数据的分析结果表明:该方法快速有效,能很好地满足局部放电在线监测的需要。
关键词 局部放电 在线监测 阈值曲线法 PD
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栓流系统动态参数关系的傅里叶级数表征
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作者 何莉萍 吴晨宝 陈宏勋 《湖南大学学报(自然科学版)》 EI CAS CSCD 1997年第3期53-55,共3页
用Fourier级数表征自动栓流系统中在栓速改变条件下动态参数栓压与栓长呈区域性、周期性变化的线性关系。旨在为栓流系统的优化设计和物流状态的计算机模拟与仿真技术提供数字化依据。
关键词 栓流系统 动态参数 自动控制系统 傅里叶级数
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采用chirp信号调制的中压配电线通信系统
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作者 尚秋峰 何文燕 《华北电力大学学报(自然科学版)》 CAS 北大核心 2008年第4期93-96,共4页
针对中压配电线信道特性,提出了一种基于分数阶Fourier变换(FRFT)的通信方法。以线性调频信号(chirp)作为调制信号,利用线性调频信号在分数阶傅里叶变换域的能量聚焦特性,提高系统的抗噪声干扰和频率选择性衰减的能力。建立了系统的仿... 针对中压配电线信道特性,提出了一种基于分数阶Fourier变换(FRFT)的通信方法。以线性调频信号(chirp)作为调制信号,利用线性调频信号在分数阶傅里叶变换域的能量聚焦特性,提高系统的抗噪声干扰和频率选择性衰减的能力。建立了系统的仿真模型,仿真结果证明了方法的可行性。 展开更多
关键词 配电线载波通信 分数阶FOURIER变换 线性调频信号 频率选择性衰落
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Seasonal Variability of Biofouling Community Structure in the Gulf of Mannar,Southeast Coast of India:A Multivariate Approach
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作者 MARIMUTHU Nithyanandam WILSON James Jerald KUMARAGURU Arumugam Kuppuswamy 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期766-776,共11页
In this research,an Underwater Biofouling Panel(UWBFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of Mannar.Forty-four biofoulers were identified from four... In this research,an Underwater Biofouling Panel(UWBFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of Mannar.Forty-four biofoulers were identified from four types of selected test panels.Among these biofoulers,Amphibalanus amphitrite(Darwin,1854)was the dominant one.The concrete panel encouraged the highest barnacle density compared to the other panels.Three series of test panels were used to assess the seasonal density of biofouling communities.The overall variation in barnacle count in the seaward and shoreward sides of all these three series were tested.They were found to be significantly different from each other.The greater variations in the barnacle density observed in this study in A-series of test panels could be due to the lack of or absence of other foulers to compete within the fortnight.The Shannon-Wiener species diversity index showed the highest diversity in wood substratum among the three series with greater accumulation of different types of fouling organisms.Multivariate analyses were also performed to understand the seasonal variation as well as the settlement pattern on the different directions of test panels based on validated data.PCA showed a strong variability(PC1 between 70.8%and 98.6%variance)between the directions of the panels in connection with barnacle density.The shade plot and CAP analysis segregated the short-term A-series test panels from the long-term(B-and C-series)test panels.Hence,the output was helpful in understanding the recruitment status of various faunal resources involved in the biofouling processes. 展开更多
关键词 BIOFOULING BARNACLE hard fouler multivariate analysis fouling biomass Gulf of Mannar
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Fourier级数法的GPS精密星历拟合研究 被引量:3
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作者 刘小强 李勇 谢瑞 《工程勘察》 CSCD 2012年第10期52-55,共4页
常用GPS精密星历拟合方法存在诸如拟合时段多为2~3h,拟合方程的阶数过高,拟合精度不够等问题,针对这些问题,本文提出了采用Fourier级数拟合GPS精密星历的方法。阐述了Fourier级数法的数学原理,给出了实现步骤,并通过拟合时段为12h的实... 常用GPS精密星历拟合方法存在诸如拟合时段多为2~3h,拟合方程的阶数过高,拟合精度不够等问题,针对这些问题,本文提出了采用Fourier级数拟合GPS精密星历的方法。阐述了Fourier级数法的数学原理,给出了实现步骤,并通过拟合时段为12h的实例数据,验证了利用8阶的Fourier级数可实现长时段的精密星历的精确拟合,拟合最大误差不大于3.5cm。本文还总结了级数的阶数和数据量的关系及迭代时初始值的确定,并对该方法的使用给出了一些合理建议。 展开更多
关键词 傅立叶级数 精密星历 最小二乘法 迭代
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对称Toeplitz矩阵相乘的一种快速算法
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作者 张曙光 《科技创新导报》 2013年第26期219-220,共2页
本文将Toeplitz矩阵分解为循环矩阵和下三角矩阵之和,以及一般卷积向循环卷积的转化,借助快速Fouier算法(FFT),给出了一种对称Toeplitz矩阵相乘的快速算法,其算法复杂性为2n2+O(nlog2n)次实乘次数,2n2-4n+2次实加次数,较之前的算法在时... 本文将Toeplitz矩阵分解为循环矩阵和下三角矩阵之和,以及一般卷积向循环卷积的转化,借助快速Fouier算法(FFT),给出了一种对称Toeplitz矩阵相乘的快速算法,其算法复杂性为2n2+O(nlog2n)次实乘次数,2n2-4n+2次实加次数,较之前的算法在时间复杂性上有所改善。 展开更多
关键词 对称Toeplitz矩阵 快速Fouier算法(FFT) 算法复杂性
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