A semi-analytical solution for random wave-induced soil response and seabed liquefaction in marine sediments

In this study, unlike most previous investigations for wave-induced soil response, a simple semi-analytical model for the random wave-induced soil response is established for an unsaturated seabed of finite thickness. Two different wave spectra, the B-M and JONSWAP spectra, are considered in the new model. The influence of random wave loading on the soil response is investigated by comparing with the corresponding representative regular wave results through a parametric study, which includes the effect of the degree of saturation, soil permeability, wave height, wave period and seabed thickness. The maximum liquefaction depth under the random waves is also examined. The difference on the soil response under the two random wave types, B-M and JONSWAP frequency spectra, is also discussed in the present work.     

A note on the effects of a thin visco-elastic mud layer on small amplitude water-wave propagation

In this note we investigated the effects of a thin visco-elastic mud layer on wave propagation. Within the framework of linear water-wave theory, analytical solutions are obtained for damping rate, dispersion relation between wave frequency and wave number, and velocity components in the water column and mud layer. The wave attenuation rate reaches a maximum value when the mud layer thickness is about the same as the mud boundary layer thickness. Heavier mud has a weaker effect on the wave damping. However, the wave attenuation rate does not always decrease as the elastic shear modulus increases. In the range of small values for elastic shear modulus, the wave attenuation can be amplified quite significantly. The current solutions are compared with experimental data with different wave conditions and mud properties. In general, good agreements are observed.     

锯缘青蟹NAGase的催化机理的判断

以p-硝基苯酚-β-D-氨基葡萄糖苷（pNP-NAG）为底物，研究产物类似物：p-羧基苯酚和苯酚对青蟹N-乙酰-β-D-氨基葡萄糖苷酶（NAGase，Ec3．2．1．52）活力的影响．结果表明：p-羧基苯酚和苯酚对该酶有抑制的作用，IC50分别为20．0和100．0mmol／dm^3．p-羧基苯酚和苯酚对酶的抑制均表现为竞争性类型，其抑制常数K1分别为5．03和25．67mmol／dm^3．结合产物N-乙酰-β-D-氨基葡萄糖（NAG）抑制作用表现为反竞争性类型，判断NAGase水解pNP-NAG反应为有序双双反应（Ordered Bi Bi）．     

Estimating the underwater light field from remote sensing of ocean color

We present a new approach that incorporates two models to estimate the underwater light field from remote sensing of ocean color. The first employs a series of analytical, semi-analytical, and empirical algorithms to retrieve the spectrum of inherent optical properties (IOPs), including the absorption and the backscatter coefficients, from the spectrum of remote sensing reflectance. The second model computes the profile of photosynthetically available radiation E _0,PAR (z) for a vertically homogeneous water column using the information of the retrieved IOPs and the ambient optical environment. This computation is based on an improved look-up table technology that possesses high accuracy, comparable with the full solution of the radiative transfer equation, and meets the computational requirement of remote sensing application. This new approach was validated by in situ measurements and an extensive model-to-model comparison with a wide range of IOPs. We successfully mapped the compensation depth by applying this new approach to process the SeaWiFS imagery. This research suggests that E _0,PAR (z) can be obtained routinely from ocean-color data and may have significant implications for the estimation of global heat and carbon budget.     

装载GPCTD传感器的海翼水下滑翔机观测数据实时质量控制

Profiles observed by Sea-Wing underwater gliders are widely applied in scientific research. However, the quality control(QC) of these data has received little attention. The mismatch between the temperature probe and conductivity cell response times generates erroneous salinities, especially across a strong thermocline. A sensor drift may occur owing to biofouling and biocide leakage into the conductivity cell when a glider has operated for several months. It is therefore critical to design a mature real-time QC procedure and develop a toolbox for the QC of Sea-Wing glider data. On the basis of temperature and salinity profiles observed by several Sea-Wing gliders each installed with a Sea-Bird Glider Payload CTD sensor, a real-time QC method including a thermal lag correction, Argo-equivalent real-time QC tests, and a simple post-processing procedure is proposed. The method can also be adopted for Petrel gliders.     

满足给定数字特征和谱的随机信号的产生

本文给出了满足给定数字特征和谱的随机序列的产生方法，即用无记忆非线性变换实现非正态随机信号的模拟．该法与Ｇｕｊａｒ法相比较，放宽了变量概率分布的限制，只要求变量矩的存在。同时考虑无记忆非线性变换对谱的影响，用异于Ｌｉｕ的方法在频域上求解输入正态分布随机序列的谱．     

渤海风暴潮的初步探讨

根据山东渤海沿岸各县县志记载的不完全统计,自汉朝初元(公元前48年)至民国27年(公元1938),渤海南部沿海发生的特大潮灾有79次之多(见表1)。其中特大潮灾如唐朝高宗上元三年(公元676年)八月,“青州大风,海溢,漂民五千余家,齐淄等七州大水”;明朝万历四十一年(公元1613年)七月,“海水溢逾百余里,坏民舍无算”。再如1938年8月31日,台风由青岛登陆,横断山东半岛西部(见图1),晚间抵达黄河口,逐渐停滯减弱,变成一个低气压。这次台风不仅在青岛造成严重灾情,整个渤海沿岸都深受其害,并且出现了历史最高水位。解放后,渤海又多次受到强风暴潮的危害。历史资料表明,渤海的菜州湾和渤海湾地区是风暴潮的多发区和严重区,这种潮灾大都出现于春秋过渡季节和盛夏台风频繁活动季节。 近几年来,国内对渤海局部地区风暴潮的研究已有许多论述,但大都是对冷锋所导致的单站风暴潮的研究,对台风潮的研究则较少。本文试图对冷锋和台风两种灾害性天气所导致的整个渤海风暴潮的一些现象作一较全面的讨论,并对其一些基本特性作一理论分析。     

代数系的FUZZY理想(英文)

作者曾给出了模糊代数系的统一定义和一个代数系上的模糊子集是模糊子代数的充要条件。本文是以上结果的继续,给出了一个模糊子代数系是模糊理想的统一定义和充要条件,是诸文献上模糊正规子群,环的模糊理想等概念的统一和推广。     

呼伦湖的近期扩张及其与全球气候变化的关系

通过近２０多年湖泊水量平衡分析发现，湖泊水位变化主要由湖盆内径流补给量的丰枯决定。进一步分析揭示，呼伦湖地区乃至整个东北地区，本世纪以来随气温升高，随水有增加的趋势。降水增加导致入湖径流量，湖水位上升，呼伦湖本世纪以来的扩张与内蒙古东部地区其他内陆湖泊的变化一致，但这在我国乃至整个亚洲内陆干旱或半干旱区是独一无二的，为此成为这一地区气候变化的指示器。     

Observations and Estimations of Directional Spectrum of Sea Waves

The directional spectrum is one of the basic characteristics of sea waves. The observations of directional spectrum of sea waves were successfully conducted at platform Bohai 8 during 1991 and 1992 using a wave gage array for the first time in China. Based on the field data, the directional spectrum which depends on the wave growth is given in this paper. Before observations, the effects of the type of gage array, the distance between the gages and the platform itself on the measured results and the precision of some methods for estimating the directional spectrum were investigated and compared with the methods of numerical simulations and model tests of multi-direcitonal irregular waves. This ensures the quality of the observations and estimations of the directional spectrum.