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941.
水下爆破工程中炸药药量的修正计算 总被引:1,自引:0,他引:1
在水下爆破工程中,所用药量一般是按照库尔公式来进行计算的。在爆炸过程中自由水面和水底面对爆炸作用会产生界面影响,为此提出了水下爆炸受到界面影响的药量修正系数Ki(i=1、2、3)的概念,以便在水下爆破施工中合理方便地确定实际药量。 相似文献
942.
Li Yan Wang Yaqin LinYian
Associate Professor Second Institute of Oceanography State Oceanic Administration Hangzhou Senior Engineer Second Institute of Oceanography State Oceanic Administration Hangzhou 《中国海洋工程》1995,(3)
- Settling characteristics of floes, including relative settling velocity, relative flocculation coefficient and flocculation exponent, are obtained by the suspended load equations for different size fractions. Data of the Changjiang Estuary suggest that level of flocculation changes from river section, river mouth (turbidity maximum) to offshore area in sequence of low, very high and high. The settling characteristics of floes reflected by in situ estimation performs a similar feature as that obtained from still water experiment. 相似文献
943.
苏育嵩 《中国海洋大学学报(自然科学版)》1989,(Z1)
现行的场预报方法,一般是根据预报量之间的统计关系,进行场分解,而后用经验正交函数建立预报方程,但却很少考虑到外界因子的作用。本文尝试把影响因于引入经验正交预报方法中。在这种优选因子场预报方法中,作者不仅考虑预报量之间内部的相互关系,而且也考虑了外部因子的影响,借助于从综合因子中优选因子,可以建立对于预报数量和等级都适用的最优预报方程。提出了权重相关系数的概念。与其他相关系数之间的明显差别是,它具有场的特征。本文还介绍了水湿的盐度预报的一些实例。 相似文献
944.
945.
关于洛伦茨曲线与吉尼系数的探讨 总被引:1,自引:0,他引:1
陈峥 《中国海洋大学学报(自然科学版)》2001,31(3):455-460
作者运用数理统计的手段 ,分析了在经济学中广为应用的描述性曲线 -洛伦茨曲线y =L ( t)的数理实质 ,给出其积分表达式 ,L ( t) =( 1/ Eξ) ∫t0 F-1( u) du,并在此基础上讨论某些分布的吉尼系数与标准差系数的关系 ,同时给出一个讨论一般分布函数的吉尼系数的途径 :将分布函数展成泰勒级数 相似文献
946.
947.
This paper presents a brief review of the results on the interaction between waves and muddy bottom obtained during the last decade including the results obtained by the author at the Coastal Engineering Laboratory of Tianjin University. 相似文献
948.
南黄海沉积物粒度分布参数计算方法的比较 总被引:2,自引:0,他引:2
赵珍清 《海洋地质与第四纪地质》1992,(3)
本文将南黄海第四纪沉积物,用不同方法计算的粒度分布参数作了统计分析。作为对比的计算方法为(1)Folk和Ward的图解法;(2)海洋调查规范(1975)的方法和(3)矩法。结果表明:三种方法得出的数据间高度相关,可藉回归方程相互对比。 相似文献
949.
Óscar A. Barocio-León Roberto Millán-Núñez Eduardo Santamaría-del-Ángel Adriana González-Silvera Charles C. Trees 《Journal of Oceanography》2006,62(6):873-885
We have estimated the spatial variability of phytoplankton specific absorption coefficients (a*
ph
) in the water column of the California Current System during November 2002, taking into account the variability in pigment
composition and phytoplankton community structure and size. Oligotrophic conditions (surface Chl < 0.2 mg m−3) dominated offshore, while mesotrophic conditions (surface Chl 0.2 to 2.0 mg m−3) where found inshore. The specific absorption coefficient at 440 [a*
ph
(440)] ranged from 0.025–0.281 m2mg−1 while at 675 nm [a*
ph
(675)] it varied between 0.014 and 0.087 m2mg−1. The implementation of a size index based on HPLC data showed the community structure was dominated by picoplankton. This
would reduce the package effect in the variability of a*
ph
(675). Normalized a
ph
curves were classified in two groups according to their shape, separating all spectra with peaks between 440 and 550 nm as
the second group. Most samples in the first group were from surface layers, while the second group were from the deep chlorophyll
maximum or deeper. Accessory photoprotective pigments (APP) tended to decrease with depth and accessory photosynthetic pigments
(APS) to increase, indicating the importance of photoprotective mechanisms in surface layers and adaptation to low light at
depth. Samples with higher ratios of APP:APS (>0.4) were considered as phytoplankton adapted to high irradiances, and lower
ratios (<0.26) as adapted to low irradiances. We found a good relationship between APP:APS and a*
ph
(440) for the deeper layer (DCM and below), but no clear evidence of the factors causing the variability of a*
ph
(440) in the upper layer. 相似文献
950.
Bin Lv Guo-liang Qi Guan-bao Li Guang-ming Kan Jing-qiang Wang Jie Liu 《Marine Georesources & Geotechnology》2020,38(3):363-373
AbstractA new kind of visual acoustic measurement system was developed to obtain the acoustic characteristics of seabed sediment and the working state of in situ measuring equipment in real time. The control unit of the system structure is mainly made up of the underwater control unit and the deck control unit. In comparison with similar traditional systems, the system can transmit the working video image, the measured acoustic data and the waveform synchronous from the underwater control equipment to the deck control unit through the connecting cable. Apart from self-contained in situ measurement, the working modes of it include visual online real-time control. In order to guarantee the stability and measurement precision of the video control system, the process control of in situ measurement was strictly tested in the experimental tank. In 2017, sea trials of the in situ measurement system was carried out in the South China Sea. In the process, data related to measurement, including the acoustic velocity and attenuation coefficient of the seabed sediment, were obtained as well. The results from sea trials show that the control process of the visual system is intuitive, reliable and accurate, and therefore it can be popularized and applied. 相似文献