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1.
地壳的各向异性分析计算中,非常重要的两个参数是:分裂的横波中高速和低速横波之间的时间延迟和高速横波的极化方向。在试算中的合成地震记录显示两种方法(ASR和AIR)都大大快于目前使用的数字方法(分别是10倍和100倍),而且结果与模型值一致。野外资料的分析计算显示ASR相对于AIR的抗干扰性要强且结果稳定。  相似文献   

2.
AVO技术在水合物调查评价的应用中应注意的问题   总被引:2,自引:0,他引:2  
利用AVO技术进行真假BSR识别和水合物储集层预测时应注意的问题是:①是否搞清了水合物沉积层与其上下围岩(层)之间的地球物理特征(尤其是纵、横波速度)差异以及不同的岩性组合带来的AVO效应的差异;②是否搞清了水合物沉积层与其它能引起类似于BSR反射特征的岩石(如火山岩)之间的地球物理特征(尤其是纵、横波速度)差异。只有搞清这些问题,在应用AVO技术进行真假BSR识别和储集层预测时才能有的放矢,辩别真假,避免AVO技术在应用到石油天然气勘探的早期所出现的应用“陷阱”。  相似文献   

3.
南麂列岛自然保护区药用海藻资源及其应用   总被引:1,自引:0,他引:1  
本文报道了南麂列岛国家海洋自然保护区药用海藻的种类组成及其应用。经初步鉴定南麂列岛共有海藻类400余种,其中已知具有药用功效的海藻111种(小于20μm的微型藻类为16种,20~200μm的小型藻类为9种,大于200μm的大型海藻类为86种),隶属于红藻门49种、褐藻门20种、硅藻门15种、绿藻门14种、蓝藻门8种和甲藻门5种。根据藻类的药理、生理特性及药用功效,可划分为9类:(1)抗菌药(AF);(2)抗凝血、止血药(AB);(3)抗病毒药(AD);(4)抗高血压药(AH);(5)清热解毒药(APT);(6)驱虫药(AI);(7)抗肿瘤药(AT);(8)抗心脑血管药(BC);(9)抗艾滋病药(AIDS)。  相似文献   

4.
根据珠江(广州河段)沉积物中As(T),As(Ⅲ),As(Ⅴ),MMA,DMA含量与Fe,Al,K,Ca,Mg及有机碳含量,研究了南亚热带近河口区沉积物中As形态的存在特征,并计算AS形态间及与其它元素间的相关性,从而说明AS形态在河口区的存在及迁移特征。  相似文献   

5.
分析了华贵栉孔扇贝Chlamysnobilis(Reeve)、合浦珠母贝Pinctadamatensii(Duuker)、翡翠贻贝Pernavirldis(Linnaeus)的软体部、肝胰腺和生殖腺的脂肪酸组成及含量。3种贝的各组织中,不饱和脂肪酸含量均较饱和脂肪酸含量高。多不饱和脂肪酸(PUFA)含量丰富,其中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)含量相当高,占总脂肪的25.26%-27.21%。3种贝中,翡翠贻贝的油含量最高(13.68%),软体部的EPA和DHA含量也较高(26.95%),最具开发利用价值。  相似文献   

6.
本文讨论了利用SAR 图像监测海上石油污染的理论依据和环境条件,并根据RADARSAT 卫星装载的合成孔径雷达(SAR)图像对渤海CB-6A 井组发生的原油(气)泄漏事件进行了初步的研究和分析。  相似文献   

7.
分析几种低频线谱参数估计方法的优点与不足,结合舰艇噪声低频线谱所具有的特点,应用数字滤波一相关谱估计(DF—C)和自回归移动平均(ARMA)模型相结合的方法(DF—ARMA)对低频线谱作估计,所得线谱的强度和频率估计值准确度较高。  相似文献   

8.
谈美国SonTek水文仪器公司声学多普勒测流仪器   总被引:2,自引:0,他引:2  
本文简要介绍了美国 Son Tek 水文仪器公司产品三大系列。(1) 声学多普勒水流剖面仪( A D P) 系列;(2) 声学多普勒水流计( A D C M) 系列;(3) 声学多普勒流速计( A D V) 系列。对产品的特点、技术性能指示及海上实验和应用也进行了描述。  相似文献   

9.
毛蚶(Arca subcrenata)体液来克丁的凝集作用   总被引:6,自引:0,他引:6  
用甲状腺球蛋白琼脂糖4B亲和层析毛蚶( Arca subcrenata )体液来克丁(ASL)。试验了ASL对9 属33 株来自不同生境的细菌、安哥拉兔血细胞和人的A,B,O 型血红细胞的凝集作用。结果表明ASL对24.2×10- 2的参试菌株具凝集活性(BA)。被凝者主要是来自南极及毛蚶和对虾体的细菌。对所试红细胞则显示了效价不一的凝集活动(HA)。ASL的凝血活性受半乳糖、乳糖的一定抑制。文章讨论了ASL在毛蚶的防御活动中可能起的作用。  相似文献   

10.
3种海洋养殖贝类体内的脂肪酸组成   总被引:5,自引:1,他引:4  
庆宁  林岳光 《热带海洋》1999,18(1):79-82
分析了华贵栉孔扇贝、合浦珠母贝、翡翠贻贝的软体部、肝胰腺和生殖腺的脂肪酸组成及含量,3种贝的各组织中,不饱和脂肪酸含量均较饱和脂肪酸含量高。多不饱和脂肪酸(PUFA)含量丰富,其中二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)含量相当高,占总脂肪的25.26% ̄27.21%,3种贝中,翡翠贻贝的油气含量最高(13.68%),软体部的EPA和DHA含量也较高(26.95%),最具开发利用价值。  相似文献   

11.
樊京  蔡广宇 《海洋学报》2010,32(9):6084-6088
用数值仿真在微波X波段研究了金属开口谐振环和杆阵列这一最基本的谐振结构.通过合理的参数调节,这种结构在10.91 GHz附近可以表现出高达98%的吸收率,并且半高峰宽达到3.5 GHz.用散射参量提取法计算其有效电磁参数,发现在谐振频率附近其介电常数、磁导率和折射率的实部均为负值.相比于传统的左手材料,这种结构的电磁参数在谐振区域均具有较大的虚部,是形成高吸收率的根本原因.本文的左手材料吸收器在电磁加热、电磁隐身等领域具有许多潜在的应用.  相似文献   

12.
The hydrodynamic properties of long rigid floating pontoon interacting with linear oblique waves in water of finite arbitrary depth are examined theoretically. The flow is idealized as linearized, velocity potentials are expressed in the form of eigen-function expansions with unknown coefficients. The fluid domain is split into three regions, region (1) wave-ward of the structure, region (2) in the lee of the structure, and region (3) beneath the structure. The different hydrodynamic quantities of interest such as the exciting forces, added mass and damping coefficients, reflection and transmission coefficients were studied for an applicable range of wave/structure parameters. Assuming rigid body motions, dynamic responses of the moored structure is approximately calculated through three equations of motion. Floating pontoons proved to be a convenient alternative for protection from waves in shallow water. The present method of solution was found to be computationally efficient, and results are comparable to those obtained through other techniques.  相似文献   

13.
Analysis of Wave Loads on A Semi-Submersible Platform   总被引:10,自引:0,他引:10  
QIAN  Kun 《中国海洋工程》2002,16(3):395-406
For the global and structural fatigue strength analysis of a semi-submersible platform, wave loads under design conditions are calculated by use of the three-dimensional boundary element method. Methods for calculating the forward-speed free-surface Green function are discussed and a computer program with this Green function is developed. According to the special rules, the wave loads under several typical design conditions of the platform are calculated. The maximum vertical bending moment, torsion moment and horizontal split force are determined from a series of contour maps of wave loads for the wave period of 5 to 18 seconds at a certain interval and the wave phase of 0°to 360°at a certain interval. The wave height is determined by the function of wave period with a given exceedance probability. The maximum wave loads under the combination of wave parameters are used as the input of hydrodynamic pressure in the three-dimensional finite element analysis process. The transfer functions of wave loads  相似文献   

14.
A new set of multi-channel sea surface temperature (MCSST) equations for the Advanced Very High Resolution Radiometer (AVHRR) on NOAA-9 is derived from regression analyses between two-channel brightness temperatures andin situ SST obtained from moored buoys around Japan. Two equations are derived: one for daytime and the other for nighttime. They are linear split window type and both the equations contain a term dependent on satellite zenith angle, which has not been accounted for in the previous daytime split window equations for NOAA-9. It is shown that the new set of equation can give SSTs in much better precision than those without the zenith-angle-dependent terms. It is also found that the split window equation for NOAA-9 provided by the National Oceanographic and Atmospheric Administration/National Environmental Satellite, Data and Information Service (NOAA/NESDIS) considerably underestimates the daytime SSTs; sometimes nighttime SSTs are evenhigher than daytime SSTs. This is because the zenith angle effect to the radiation deficiet is neglected in the daytime equation by NOAA/NESDIS. By using the new MCSST equations, it is expected that the quality of satellite MCSST would be much improved, at least in regional applications around Japan, for the period of NOAA-9's operation.  相似文献   

15.
An ahead-looking probe of some kind, optical or acoustic, is critical when one is attempting seafloor exploration from a mobile platform. A single-frequency, split aperture sonar system can be used for this purpose, but a wideband monopulse sonar offers many advantages. It computes a running estimate of the vertical directional cosine of the source of the echo, and can thus reveal the positions of multiple wave scatterers as long as their echoes can still be time resolved. Theoretical studies of its performance have been made previously, but were directly applicable only to extremely simple seafloor geometries. A new time-domain digital simulation that largely circumvents this limitation has been developed. The simulation also provides a means for testing the theory and optimizing system parameters. The reverberation model does not account for some features of acoustic backscattering such as diffraction, but it is believed to be adequate for the investigation of most signal processing aspects of the sonar system. The theory of the simulation is developed and several examples are presented and discussed. In addition, some preliminary results are presented from a sea test that used the air-sea interface as a surrogate seafloor  相似文献   

16.
白玉川  于天一 《海洋学报》1998,20(5):126-135
以Navier-Stokes方程为基础,经代数坐标变换导出模式方程,然后在该坐标系下将三维流场进行垂直分层,并在每一层内积分模式方程。在数值模拟求解方面,采用分步、特征差分近似与Galerkin集中质量有限元相结合的方法进行求解。在实际应用方面,对广西廉州湾潮流进行了三维模拟计算。  相似文献   

17.
The European ferry sector is the largest ferry sector globally and one of the key environmental issues facing the sector is the mitigation of greenhouse gas emissions. This paper provides an analysis of how the EU ferry procurement policies lead to lack of implementation of energy efficiency measures, contrary to the EU's key objective of reducing CO2 emissions in ferries within the EU region. This paper is the first analysis to examine the public–private sector interaction in transport and how this leads to a lack of implementation of energy efficiency measures. Analysing the sector using agency theory suggests that split incentives are pervasive and can stymie attempts to improve the energy efficiency of ferry services in the procurement of ferries. The findings suggest that there is a need to review current ferry procurement policies with a view to devising procurement policies that can address the split incentives, as well as other policies, that are outside the scope of procurement policies, which can be used to minimise the split incentives.  相似文献   

18.
针对目前海冰信息解译时对海冰外缘线及面积信息提取不精确、业务化应用不强问题,提出一种基于分裂Bregman算法的海冰外缘线自动提取方法,并通过遥感影像预处理、算法程序化等工作步骤,将该算法应用到业务化海冰信息解译工作中。方法:分别选取五景中、高空间分辨率的可见光卫星遥感影像,将影像上待提取海冰区域首先进行不规则图像裁剪、图像增强等预处理工作,然后基于变分水平集及快速分裂Bregman投影方法进行了海冰外缘线信息的提取,并对提取出的海冰面积进行量化,最后与传统人工提取海冰信息进行了比较。实验结果表明,基于变分水平集及其快速分裂Bregman算法提取的海冰信息,具有提取的海冰边缘精确、自动化程度高、提取结果稳定可靠等优点。  相似文献   

19.
陈维  顾杰  李雯婷  秦欣 《海洋科学》2011,35(1):70-74
根据实测水文及泥沙等资料,采用现在较成熟的且应用广泛的BP人工神经网络建立了北支0m以下河槽容积与大通流量、大通输沙量及北支分流比3个因子问的神经网络模型,网络结构为3.1-7-1,通过选择合适的参数,模型训练较好,预测结果与线性回归模型预测结果相近,说明BP神经网络模型能够广泛应用于河口水文等方面的预报.  相似文献   

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