北部湾沿岸海区设计波浪的确定     

滕学春  吴秀杰  刘丽惠 《海洋科学进展》1995,(3)

本文基于北部湾沿岸海区多年的实测资料，于不同海区主浪向和次主浪向分别取年极值波高为样本资料．采用Ｐ－Ⅲ型和短期测波资料频率分析方法，分别估算了各海区不同重现期的设计波高，并依据式（１）计算出相应的平均周期。尽管样本资料和估算方法不变，但每次估算的结果互不相同，其差异甚至很大．利用Ｋｏｌｍｏｇｏｒｏｆｆ等适合度方法检验所得的结果，能够准确地判断出沿岸各海区不同重现期的最佳设计波浪。  相似文献   

均匀设计在后棘藻培养基中的应用   总被引：2，自引：0，他引：2       下载免费PDF全文

徐年军  张学成  范晓 《海洋科学》2003,27(1):38-42

将均匀设计的方法应用于一种海洋微藻：后棘藻（Ellipsoidion)培养基的优化。设计了硝氮、氨氮、磷酸盐三因素各五个浓度水平的试验，根据均匀设计表设计了10种培养基，检测细胞浓度、脂肪酸含量和产量。结果表明：在硝氮、氨氮浓度均为1．92mmol/L，磷酸盐浓度为0．082mmol/L，细胞浓度达到最大值167．23mg/L。在硝氮浓度为0．84mmol/L，氨氮浓度为3．38mmol/L，磷酸盐浓度为0．07mmol/L时，EPA含量达到最大值7．748％。在硝氮浓度为0．915mmol/L，氨氮浓度为1．92mmol/L，磷酸盐浓度为0．072mmol/L时，EPA产量达到最大值9．999mg/L。  相似文献   

桶形基础及其作用下的粉质土海床失稳机制研究的试验设计   总被引：1，自引：0，他引：1  

齐剑峰  冯秀丽  林霖  李安龙  杨少丽  周松望  刘涛 《中国海洋大学学报(自然科学版)》2002,32(6):949-955

在阅读、分析以往的有关资料的基础上 ,结合实际的试验条件 ,对桶形基础及其作用下的粉质土海床失稳机制研究的试验作出了专门设计。该设计通过配土、设计模型桶基和负压沉贯的操作过程、设置孔压传感器等实验手段 ,努力从土体破坏的角度 ,寻求负压沉贯过程中沉贯负压、沉贯阻力及孔隙水压力之间的变化关系和确定桶基的上拔力。并且指出了数据处理的基本思路 ,以利于课题的深入研究。  相似文献   

Multilevel Optimal Design of Prestressed Lightweight Concrete-Steel Platform Structures     

WANG  Licheng 《中国海洋工程》2002,16(1):69-78

The concrete-steel platform structure is rather complicated because it involves such materials as concrete, reinforcing bars, steel, and so on. K the traditional dimension optimization method is employed, the optimal design of the platform will meet many handicaps, even it cannot be implemented at all. The multilevel optimal design approach is an efficient tool for the solution of large-scale engineering structures. In this paper, this approach is applied to the optimal design of a concrete-steel platform, which is formulated as a system level optimal design problem and a set of uncoupled substructure level optimal design problems. The process of optimization is a process of iteration between system level and substructure level until the objective function converges. An illustrative example indicates that this method is effective in the optimal design of concrete-steel platforms.  相似文献   

Estimation of extreme floods of the River Meuse using a stochastic weather generator and a rainfall–runoff model / Estimation des crues extrêmes de la Meuse à l'aide d'un générateur stochastique de variables météorologiques et d'un modèle pluie–débit     

《水文科学杂志》2013,58(6)

Abstract

A stochastic weather generator has been developed to simulate long daily sequences of areal rainfall and station temperature for the Belgian and French sub-basins of the River Meuse. The weather generator is based on the principle of nearest-neighbour resampling. In this method rainfall and temperature data are sampled simultaneously from multiple historical records with replacement such that the temporal and spatial correlations are well preserved. Particular emphasis is given to the use of a small number of long station records in the resampling algorithm. The distribution of the 10-day winter maxima of basin-average rainfall is quite well reproduced. The generated sequences were used as input for hydrological simulations with the semi-distributed HBV rainfall–runoff model. Though this model is capable of reproducing the flood peaks of December 1993 and January 1995, it tends to underestimate the less extreme daily peak discharges. This underestimation does not show up in the 10-day average discharges. The hydrological simulations with the generated daily rainfall and temperature data reproduce the distribution of the winter maxima of the 10-day average discharges well. Resampling based on long station records leads to lower rainfall and discharge extremes than resampling from the data over a shorter period for which areal rainfall was available.  相似文献   

东营市土地资源承载能力分析          下载免费PDF全文

于冠营  樊智  齐卉青  宋富贵  袁峥 《山东国土资源》2007,23(2):54-56

本文通过分析东营市土地资源的特点,经济和社会发展对土地的需求,以及土地后备资源的潜力,研究了东营市土地资源承载能力,提出了实现东营市耕地总量平衡的措施。  相似文献   

三峡水库梯级调度专业气象服务业务系统的研究与设计   总被引：2，自引：0，他引：2  

陈石定  王宏记  刘可群  陈良华 《成都信息工程学院学报》2005,20(6):654-656

介绍了三峡水库梯级调度专业气象保障服务业务系统的建设模式和原则以及主要建设内容和目标，并针对大气探测、通信网络、数据库、预测分析、产品发布、工作平台、业务监控、环境保障等子系统进行了规划设计。  相似文献   

有限元分析方法在天文仪器设计中的应用     

张卫锋  陈林飞 《天文研究与技术》2007,4(1):79-85

在天文仪器的设计过程中存在有大量的数值计算,且大部分的数值问题是非线性的。如何有效的解决这些计算问题,保证设计工作的顺利进行,是每一个设计工作者关心的问题。文章结合云南天文台光谱筒的有限元分析过程,论述了如何采用有限元分析方法解决大型天文仪器机械设计数值计算问题。  相似文献   

滑坡滑动面抗剪强度指标的敏感性分析     

张常亮  李同录  胡仁众 《地球科学与环境学报》2007,29(2):188-191

以三峡库区左岸归州老城滑坡为例,利用Janbu条分法和推力传递法,分析了天然抗剪强度指标c0、φ0值和饱和csat、φsat值与滑坡推力和治理造价的关系。通过综合研究和比较,发现φ值对稳定系数、剩余下滑力的影响要明显高于c值,φ值成为治理设计中保证治理安全和控制造价的关键因素。因此,在滑坡稳定性分析和治理设计中,选取合理的φ值具有重要意义。  相似文献   

Evaluation of building period formulas for seismic design     

Oh‐Sung Kwon  Eung Soo Kim 《地震工程与结构动力学》2010,39(14):1569-1583

Building period formulas in seismic design code are evaluated with over 800 apparent building periods from 191 building stations and 67 earthquake events. The evaluation is carried out with the formulas in ASCE 7‐05 for steel and RC moment‐resisting frames, shear wall buildings, braced frames, and other structural types. Qualitative comparison of measured periods and periods calculated from the code formulas shows that the formula for steel moment‐resisting frames generally predicts well the lower bound of the measured periods for all building heights. But the differences between the periods from code formula and measured periods of low‐ to‐medium rise buildings are relatively high. In addition, the periods of essential buildings designed with the importance factor are about 40% shorter than the periods of non‐essential buildings. The code formula for RC moment‐resisting frames describes well the lower bound of measured periods. The formula for braced frames accurately predicts the lower bound periods of low‐to‐medium rise buildings. The formula for shear wall buildings overestimates periods for all building heights. For buildings that are classified as other structural types, the measured building periods can be much shorter than the periods calculated with the code formula. Based on these observations, it is suggested to use C_r factor of 0.015 for shear walls and other structural types. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献