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1.
文章对入海污染物总量控制规划的几个关键问题进行了思考及探讨,提出了入海污染物总量控制规划的概念定义,确立了规划的时间、空间尺度范围,明确了规划的任务,分析了规划与其他相关规划的关系,并探讨了规划编制的目的、指导思想和原则,制定了规划编制的技术路线,为入海污染物总量控制规划的编制奠定了理论基础。  相似文献   

2.
辽宁省海洋渔业综合管理数据服务平台建设概述   总被引:1,自引:0,他引:1  
本文介绍了辽宁省海洋与渔业信息化现状,分析了现有系统存在的不足,并在此基础上建设了辽宁省海洋渔业综合管理数据服务平台,对现有信息化系统进行了梳理,实现了全省教据资源的统一管理与共享;开发了若干面向业务应用的子系统,实现了对海洋渔业管理的全方位支持;建设了数据交换共享标准与服务接口,为日后的信息化建设提供了有力的技术支撑手段。  相似文献   

3.
介绍了一种原位测量深海地热探针的控制系统设计方法。描述了探针控制系统总体设计思路,采用分散与集中相结合的控制策略,合理安排了控制任务,优化了控制系统设计;介绍了测温部件的优化设计方法,给出了系统控制电路与软件的设计方法和系统控制流程;介绍了操作软件的设计要点,对软件设计过程中的关键点给出较详细说明;最后进行了系统整体测试,验证了系统设计的可行性和稳定性。  相似文献   

4.
陆源污染物对连云港海域环境影响研究   总被引:6,自引:0,他引:6  
应用沿深平均二维模型模拟了连云港海域的潮流场,分析了该海域的潮波特性,在此基础上,应用扩散方程对连云港海域的水污染扩散进行了数值模拟,得到了港域水体的半交换期;比较分析了西大堤对该水域水交换的影响;计算了港域水体的Lagrange余流场,并分析了其对污染物运移的影响,得到了港域几个典型位置的Lagrange轨迹;计算了港域的纳潮量,综合分析了港域水体的物理自净能力。  相似文献   

5.
靳军  王沫  王东 《海洋测绘》2006,26(6):28-30,61
首先介绍了网络分析的概念,接着介绍了交通网络的基本要素,然后建立了交通网络的模型,通过确定影响交通体系中网络流的因素,实现了最优路径的选择,最后用具体的数据验证了模型的合理性。  相似文献   

6.
海洋气象学是一门边缘科学。我院建院二十五年来,海洋气象专业的教师们在积极作好教学工作的同时,也在海洋气象学方面进行了科学研究工作。在实践和理论等方面都获得了较好的成果。发现了一些有科学价值的现象,解决了一些国家急需解决的问题,提高了理论水乎,也补充了教材内容,提高了教学质量。  相似文献   

7.
对海浪液面位移模型的建模方法进行了研究,利用Phillips谱分析方法,建立了受风场和海底地形等因素影响下的海浪波面位移模型,提出了2D FFT的优化方法,提高了计算机的执行效率,解决了海浪数字仿真中的动态数据生成问题,并最终实现了不同分辨率海浪模块的拼接和渲染。  相似文献   

8.
近底管线上的波浪力   总被引:1,自引:1,他引:1  
赵德庭  任佐皋 《海洋学报》1991,13(3):393-400
本文利用物理模型试验,同步测试了近水底管线在波浪作用下的水平力和外力,并应用莫里逊公式、二阶斯托克斯波理论,按最小二乘原理统计了水平力系数CD和CM,分析了它们与KC数间的关系,提出了经验式。本文重点探讨了升力过程线的计算模式,采用傅氏级数法分析了实测升力过程线,提出了五阶升力系数及其相应的初相位值与KC数的经验关系式,从而,首次提出了计算升力和合力过程线的方法。文中还通过实例,比较了力过程线的实测值和计算值,讨论了最大合力值及其相位特征等。  相似文献   

9.
异变     
“有些动物我们永远没有机会再见到了,而另一些动物正在死亡的边缘挣扎。”新近一期《读者》刊列出另一份“新德勒名单”:巴厘虎灭绝了,爪哇虎灭绝了,袋狼灭绝了,犀牛灭绝了,野牛灭绝了,野马灭绝了……  相似文献   

10.
我国海洋测流仪器的发展与现状   总被引:3,自引:0,他引:3  
本文介绍了建国以来海洋测流仪器发展的几个主要阶段,以翔实的背景资料,论述了我国海洋测流仪器的发展与现状,肯定了我国的海洋测流仪器发展中所取得的成绩,找出了差距,并提出了今后我国海洋测流仪器的发展方向  相似文献   

11.
The main objective of the present paper is to numerically examine the residual ultimate strength characteristics of steel plates with longitudinal cracks under axial compressive actions. The present paper is a sequel to the author's previous paper [Paik, J.K., 2008. Residual ultimate strength of steel plates with longitudinal cracks under axial compression—Experiments. Ocean Engineering 35, 1775–1783]. In contrast to the previous paper, the present paper deals with nonlinear finite element method investigations. Because the test programme is usually limited to a few test models in number for many reasons, the application of nonlinear finite element methods is often more beneficial to handle a more variety of parameters of influence. In the present paper, the insights developed from a series of ANSYS nonlinear finite element method computations are documented, where the effects of the crack orientation, the crack location, the crack size, the plate thickness, and the plate aspect ratio on the residual ultimate strength of steel plates with longitudinal cracks under axial compression are discussed. The insights developed from the present work will be useful for cracking damage-tolerant design of steel-plated structures and also for health monitoring or condition assessment of aging steel-plated structures with cracking damages.  相似文献   

12.
韦波  李景文 《海洋测绘》2006,26(4):50-52
将O rac le 10g拓扑数据模型数据分为可直接可视化的数据和不可直接可视化的数据,分别叙述了基于M apX/M apX trem e对两类数据实现可视化的方法,其中对前者的实现方法不适用于后者,但对后者的实现方法能适用于前者。在可视化过程中不必考虑不可转换的O rac le对象问题。本文叙述的可视化实现方法,可为其他G IS软件平台对模型数据可视化的实现提供一定的参考。  相似文献   

13.
分析了以前大地问题中截面椭圆弧长计算方法的缺点,在运用Mathematic的基础上,提出了在这一问题上的计算方便、过程简单的新方法,并用该方法进行了一个实例计算,效果良好。  相似文献   

14.
一种适合海洋环境温度测量的新方法   总被引:2,自引:0,他引:2  
介绍了一种崭新的海洋环境温度测量方法,也可以说是一种崭新的温度测量传感器。它直接输出温度数字量,连接PC机极为方便。文中介绍了该方法的测量原理和特点;介绍了室内和海上的试验情况,给出了试验数据和曲线;展望了广阔的应用前景。  相似文献   

15.
In this paper, several mathmatical models for the pile- soil interaction are outlined. The Boundary Element Method is one of the very effective methods for the reasonable models of elasticity and elastoplasticity. The major of this paper is concerned with the Boundary Element Method for the pile-soil interaction, including general methods and calculating formulation of static and dynamic analysis of the pile and pile groups. Some results of analysis are also given.  相似文献   

16.
A system reliability estimation method for spatial jacket platforms is developed in this paper,The jacket platform is modeled into three-dimensional assembly of spatial beam and plate elements in Fi-nite Element Method(FEM).The limit failure states correspond to collapse of a series of structural mem-bers which are identified by engineering design criteria.In this paper the following aspects are taken intoaccount:the punching shear and buckiing failures in member failure modes for the tubular joints and tubu-lar columns respectively;incremental loading approach for establishment of the safety margin equations ofsystem failure;the algorithm of enumerating significant failure modes for the structural systems and otherconcepts,such as the false failure mode and the virtual limit state.The final work is devoted to the reliabili-ty analysis for a practical jacket platform presently put into operation on the Bohai Sea.The computed re-sults shows that method suggested in this paper is feasible and effective for  相似文献   

17.
Jeom Kee Paik   《Ocean Engineering》2008,35(17-18):1775-1783
The main objective of the present study is to examine the residual ultimate strength characteristics of steel plates with cracking damages under axial compressive actions through experimental investigations. The present study is a sequel of the author's previous paper (Paik, J.K., Satish Kumar, Y.V., Lee, J.M., 2005. Ultimate strength of cracked plate elements under axial compression or tension. Thin-Walled Structures, 43, 237–272). In contrast to the previous paper which dealt with transverse cracks located in the direction normal to the axial loading direction, the present paper is concerned with longitudinal cracks which are located in parallel to the axial loading direction. Similar to the previous paper, the orientation/location and size of cracks inside the plates are varied for the present experimental investigations. The details of experimental results are documented. The database and insights developed from the present work will be useful for cracking damage-tolerant design of steel-plated structures and also for condition assessment or health monitoring of aging steel-plated structures.  相似文献   

18.
浅水域生存工况下系泊浮筒系统三维运动   总被引:1,自引:0,他引:1  
本文提出一个浅水域生存工况下,多锚链系泊浮筒系统三维运动的工程计算模型,对链系采用射的法计算,使其与浮筒运动计算相匹配。对不同的风波流方向及链刚度,计算了浮筒的运动及链力,结果显示本文的模型是合理的。  相似文献   

19.
Handling of heavy structures demand unusual crane capacity. Availability of such cranes may be limited in developing countries. An innovative way to construct and launch heavy concrete structures in a developing country, where crane availability is rare, to lift, transport and handle heavy structures, is discussed in this paper. Heavy caissons are used in the marine environment as breakwaters, as berthing facilities for vessels, as gravity structures to absorb energy from waves, etc. The methodology for constructing multi-caissons on-board a barge and then on-board a floating dock is the subject of this paper. The respective feasibilities are discussed.The free floating condition of the caisson and its righting arm stability are described. At first the caisson was considered as its lip wall opened to the sea. The case of lip wall closed for more buoyancy is also considered. The stability of the barge and floating docks is shown for various stages of completion of construction. After investigating many factors, a safe procedure for construction and launching thereafter is described in this paper. The problem of handling a heavy concrete structure from the view point of a naval architect is highlighted.  相似文献   

20.
海面风场与3.2厘米微波散射特性的研究   总被引:1,自引:0,他引:1  
海面风场遥感的基础工作之一是微波散射特性的研究。美国于一九七八年发射了一颗海洋卫星Seasat-A[3],卫星上载有微波散射计,它被用来遥感全球风场,其测量风速范围为3—25m/s,测风速的精度为±2m/s或±10%,海面上分辨率达50公里。在海洋卫星发射以前,他们对海面风速与海面微波散射特性之间的关系已作了充分的研究,这样才能判读星载或机载上所得到的遥感数据。国外在这方面做了大量的工作,积累了大量的数据。例如,美国学者格兰特和易普利将雷达散射计架在桥上俯视河水,找出了3.2厘米、1.25厘米、8.6毫米海面回波与风速的函数关系[1]。  相似文献   

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