Stochastic Analysis Method of Sea Environment Simulated by Numerical Models

1 .IntroductionNumericalmodelsmostwidelyusedforseaenvironmentandsedimenttransportfocusonsolvingseriesofdifferentialequations .Theinputandoutputofanumericalmodelareconsideredasdecisivefactors .Butinrealitythecausesofnaturaleventssuchasmeteorological,astronomical,oceanograph ic ,geomorphologicandgeophysicalfactorsarerandom .Therearemanyuncertaintiesinvolvedininputfactorsinnumericalmodels .Correspondinglytheoutputsofnumericalmodelsarealsorandom .There fore ,theoutputparametersofnumericalmodelsca…     

台站用百叶箱内外气温比对与分析

用双通道自动测温表对台站用的百叶箱内外气温进行了同步比对测量与分析。指出自然通风时，百叶箱对箱内气温变化产生一定程度的滞后和热辐射作用。滞后作用较明显。     

岩样孔隙汞渗入量超声法精密测定

采用声学方法精密测定汞被高压强压入储油岩样的渗入体积，对岩芯孔隙结构测定中的汞体积计量方法作了重要改进。本方法以无水酒精作为计量工作介质，在其中发射声波，通过对汞界面反射声波的识别，进行非接触的声学测量，从根本上解决了当前国内外采用的电阻法，电容法无法避免的由于汞腐蚀或油污染而要求经常进行与有毒汞接触的清洗，并且确保了计量系统工作性能的长期稳定与准确可靠。在０．０１ＭＰａ至５０ＭＰａ压强范围内连续计量，量程０～１０ｍｌ，准确度０．０１ｍｌ。     

海洋和海岸工程可靠度分析的几个问题

研究可靠度分析中的几个重要问题：１．直接求解非高斯过程、具有不同相关性的多变量情况下的结构失效概率问题；２．荷载的不确定性分析及其订正；３．荷载的相关性对结构失效概率的影响及灵敏度分析．作为实例对直立堤和导管架平台进行计算．     

灰色系统在电敏感区法粒度分析曲线外推技术中的应用

根据TAI型库尔特计数器单管粒度分析结果,利用灰色系统建立GM(1,1)预测模型,对样品频率曲线进行外推处理,可获得小于仪器基线通道阈值颗粒的体积百分比含量,并将结果与入重-出重法测定结果进行对比,精度较高。为电敏感区法粒度分析资料的外推处理提供了新的方法。     

Uncertainty and joint probability of sea ice loads

Ｕｎｃｅｒｔａｉｎｔｙａｎｄｊｏｉｎｔｐｒｏｂａｂｉｌｉｔｙｏｆｓｅａｉｃｅｌｏａｄｓ￥ＬｉｕＤｅｆｕ；ＹａｎｇＹｏｎｇｃｈｕｎ；ＷａｎｇＣｈａｏａｎｄＬｉＴｏｎｇｋｕｉ（ＯｃｅａｎＵｎｉｖｅｒｓｉｔｙｏｆＱｉｎｇｄａｏ，Ｑｉｎｇｄａｏ２６６００３，...     

声相关海流剖面(ACCP)测量的流速估值方法

声相关海流剖面（ACCP）测量技术对水体回波信号进行空间相关处理来估计流速值，与声学多普勒海流剖面仪（ADCP）相比ACCP的工作频工，更适合深海测流应用，ACCP测量系统对回波信号进行时空相关处理，根据相关函数的位置来估计被测水团的流速值，ACCP从信号中提取流速值要运用参数估计技术，本文介绍了采用极大似然法和最小二乘法进行流速参数的处理方法，给出一些典型流速情形的数值计算结果。     

Study on visual control system of acoustic in situ measurement technology for survey of seafloor sediment

Abstract

A 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.