Fortran与Delphi混合编程及其在造波控制系统中的应用     

王崇贤  张庆河  徐海华 《海洋技术学报》2005,24(3):88-91

在介绍实验室造波原理的基础上,提出了使用混合编程进行造波系统控制的思路,并且给出了一个应用Fortran和Delphi混合编程方法实现波浪水槽中不规则波生成的实验实例,结果表明,利用多语言集成方法实现海洋测量设备的自动控制具有较大优势.  相似文献   

A study of dissipation of wind-waves by mud at Cassino Beach,Brazil: Prediction and inversion     

W. Erick Rogers  K. Todd Holland 《Continental Shelf Research》2009

The impact of a non-rigid seafloor on the wave climate at Cassino Beach, Brazil, May–June 2005 is studied using field measurements and a numerical wave model. The measurements consist of wave data at four locations; rheology and mud thickness from grab samples; and an estimate of the horizontal distribution of mud based on echo-soundings. The dissipation of waves by a non-rigid bottom is represented in the wave model by treating the mud layer as a viscous fluid. Applied for 431 time periods, the model without this type of dissipation has a strong tendency to overpredict nearshore wave energy, except during a period of large storm waves. Two model variations which include this dissipation have a modest tendency to underpredict the nearshore wave energy. An inversion methodology is developed and applied to infer an alternate mud distribution which, when used with the wave model, yields the observed waveheights.  相似文献   

Earthquake shaking scenarios for the metropolitan area of Lisbon   总被引：2，自引：0，他引：2  

A. Carvalho  G. Zonno  G. Franceschina  J. Bil Serra  A. Campos Costa 《Soil Dynamics and Earthquake Engineering》2008,28(5):347-364

In this study, we simulate and compare ground motion shaking in the city of Lisbon and surrounding counties (metropolitan area of Lisbon (MAL)), using two possible earthquake models: the onshore source area of Lower Tagus Valley, M5.7 and M4.7 and the offshore source area, Marques de Pombal Fault, M7.6, one of the possible source of the 1755 Lisbon earthquake. The stochastic and a new hybrid stochastic-deterministic approach (DSM) are used in order to evaluate the ground shaking and to characterize its spatial variability. Results are presented in terms of response acceleration spectra (PSA) and peak ground acceleration (PGA) with respect to bedrock and surface. Site effects are evaluated by means of equivalent stochastic non-linear one-dimensional ground responses analysis, performed for a set of stratified soil profile units properly designed to cope with the soil site conditions of MAL region. A sensitive study is carried out using different input parameters and different approaches in order to give the basic information to evaluate the range of uncertainty in seismic scenarios.  相似文献   

台湾某钢框架大楼采用阻尼器补强结构减震效果评析     

林增吉  吕西林  章红梅 《地震工程与工程振动》2008,28(2):122-130

阻尼器是一种效果良好的减震装置,将阻尼器安装于结构中能够适时为结构体系提供阻尼力,从而减小地震作用对结构的破坏。黏滞阻尼器对振动的反应比较敏感,在结构受到较小振动时就可以发挥其减震效果,其阻尼力会随着振动周期和使用状态温度的不同而变化。当地震发生时,安装在结构中的阻尼器会消减地震作用,降低传导到主结构体系的地震能量,减小结构相对位移。本文介绍了黏滞阻尼器的工作原理和安装有黏滞阻尼器的结构体系的阻尼比的计算方法,对减震结构的减震效果的评析方法做出探讨,并以一安装有黏滞阻尼器的台湾某既有钢框架结构为例,分析了(1)该结构在遭受地震作用时的地震反应;(2)该结构体系在不同地震作用水平时的阻尼比,包括主体结构阻尼比和黏滞阻尼器阻尼比;(3)结构安装黏滞阻尼器后的减震效果。实例对本文的减震评析方法和减震效果进行了说明和分析,计算及分析结果表明利用黏滞阻尼器加固既有结构能够取得较好的减震效果,本文所提减震效果评析方法是一种实用有效的评析方法,对类似工程的减震评析具有一定的参考价值。  相似文献   

海岸带浅海水深高光谱遥感反演方法研究   总被引：3，自引：1，他引：2  

王晶晶  田庆久 《地理科学》2007,27(6):843-848

近红外波段(760~900 nm)反射率对水深最为敏感,通过波段比值方法可以提高与水深的相关性,而711nm处反射率一阶微分值与水深的相关系数高达-0.87。对于近岸混浊度高的样本,单波段和比值模型反演效果不好,平均相对误差均高于30%;而光谱微分模型的精度较好,平均相对误差为17%。研究结果证明:水体反射率的一阶微分可以有效地削弱水质变化给水深反演带来的误差。  相似文献   

过去200 ka北半球δ18O海温谱及其数值模拟   总被引：4，自引：1，他引：3  

戴新刚 《冰川冻土》2000,22(4):317-322

冰期和间冰期交替循环是第四纪古气候变化的基本特征,大洋底部沉积物中的有孔虫δ＾１８Ｏ记录表明了这种循环具有约１００ｋａ,４１ｋａ和２３ｋａ等几个主主要周期成分,它们均位于Ｍｉｌａｎｋｏｖｉｔｈｃ频率带上,用δ＾１８Ｏ记录恢复的海温谱不仅随纬度变化,而且冷季与暖之间存在着明显的差别,用一个由海、冰、气耦合的二维气候模式出了δ＾１８Ｏ海温谱的主要特征,在一定程度上检验了Ｍｉｌａｎｋｏｖｉｔｃｈ的天文古  相似文献   

A Study of Near- and Super-Critical Fluids Using Diamond Anvil Cell and in-Situ FT-IR Spectroscopy   总被引：2，自引：0，他引：2  

HU Shumin  ZHANG Ronghu  ZHANG Xuetong 《《地质学报》英文版》2000,74(2):412-417

The phase relation and solution structure of water and NaCl aqueous solution have been observed and examined by using the hydrothermal diamond anvil cell (HDAC) at elevated temperatures and pressures and the in situ FT-IR spectroscopy. The temperature of observations ranges from 25 to 850° C and the pressure up to 10 or 30 kb. At first, we observed the phase transition process from halite+liquid+vapour (H+L+V) to L+H, then to L (or supercritical fluid, SCF), and another path: H+L+V? L+V? L (or SCF) in heating process. By means of the visual microscope, the authors found that in the L+V immiscibility field L+V exhibits an ordered structure, i.e. a large visual cluster of solvent around ions. The liquid phase is manifested by vapour bubbles. When phase transitions are observed, the authors examined their infrared spectra by using the FT-IR microscopy simultaneously. In the case of the phase transition from liquid (L) to liquid + vapor (L+V) immisciblity field of NaCl solutions, a sudden change (strong frequency shift) of infrared spectra of the aqueous solution is observed near the critical temperature of water as the temperature is raised from 25 to 650° C. The frequency of the maximum intensity of OH symmetric and asymmetric vibration varies with respect to temperature. The sharp peak of the OH stretching vibration of the maximum intensity appears in an interval from 300 to 400° C. It is indicated that the hydrogen bonding network is weakened and broken at last near the critical point of water, which causes the aqueous solution to become more associated. Besides, a pressure indicator (a mineral or compound) was introduced to the HDAC.  相似文献   

Granite deformation and behavior of acoustic emission sequence under the temperature and pressure condition at different crust depths     

蒋海昆  张流  周永胜 《地震学报(英文版)》2000,13(4):424-433

IntroductionFocal depths of shallow strong intraplate earthquakes are mostly distributed in the highstrength range of lithosphere controlled by the rheology property of granite and diorite (Brace,Kohlstedt, 1980; Sibson, 1982; Meissner, Strehlau, 1982; CHEN, Molnap 1983). This is obviouslyrelated to the change of rock deformation characteriStics at different crust depths. So, for earthquake stUdy, both of the rock failure types (fractUre or rock flow) and its mechanical instabilityforms (…  相似文献   

四川平武雪宝顶绿柱石的振动光谱   总被引：6，自引：0，他引：6  

郭延军  王汝成  徐士进 《高校地质学报》2000,6(2):201-204

自然界中绿柱石晶体多为柱状,具板状晶形的绿柱石非常少见。对产 于四川雪宝顶 云英岩晶洞中的无色透明板状绿柱石及产于雪宝顶蒲口坡石英脉中的绿柱石进行了红外和拉 曼光谱分析,并与产于阿尔泰三号伟晶岩脉中的柱状绿柱石进行了比较。雪宝顶两个绿柱 石的结构通道中的水以II型水为主,而阿尔泰绿柱石结构通道中的水以I型水为主。雪宝顶 绿柱石中Li对Be的替换也对它的红外及拉曼光谱造成了影响。  相似文献   

Infrared photometry for variable stars of selected types in 1978–1999     

O. G. Taranova 《Astronomy Letters》2000,26(6):404-412

We present and discuss IR observations for 35 stars of different variability types averaged over many years. These include about twenty symbiotic stars, four W Ser stars and one Algol, six Miras, etc.  相似文献