GPS-RTK在水利工程测量中应用

本文针对在水利工程测量中使用GPS-RTK作业出现的有关坐标高程转换、初始化、伪值等问题进行分析,通过实践提出解决问题的办法。     

Curvature of Flexibility Matrix for Damage Identification in Legs of Jacket Platforms

In this paper a new nondestructive damage identification method is introduced. The method based on flexibility matrix can be used to detect and locate structm＇al damage and evaluate the severity of damage in legs of jacket platforms by modal parameters of a structure. With the modal data for only the few lower modes in both the intact and damaged states, the one-dimensional and two-dimensional distributed curvatures can be used to analyze damage location and the severity. Instead of directly comparing the curvatures before and ＇after damage, the method here uses modal parameters only in the damaged structure to detect the damage and it consists of three parts. First, ilexibility matrix is obtained by use of the absolute maximum in each column. Second, because the legs of jacket platforms are the pipe-like structure, the circumferential flexibility curvature matrix is obtained by use of the circular curvature. At last, equivalent curvature ratio is defined and the curve meaning equivalent curvature ratio and the severity of damage relationship for one element is given through the data of damage severity from ten percent to ninety percent by numerical simulation. Many existing damage detection methods need two steps, locate the damage firstly and evaluate the severity of the damage. However, the method present- ed! in this paper can locate and then evaluate the severity of damage at the same time. The numerical analysis results in- dicate that the present method is effective, useful and only need the first and the second mode data of the structure.     

内蒙古乌兰浩特地区萤石矿床成矿预测

内蒙古乌兰浩特地区拥有丰富的萤石矿资源,虽然地方上矿产开发力度大,但成矿研究相对较少,为此,开展该地区的成矿预测研究.本研究运用流体包裹体测量方法结合矿床地质特征探讨成矿模式,并采用伽马能谱测量技术对乌兰浩特地区的萤石矿床进行成矿预测,进而分析找矿靶区.结果表明,该区域属于浅层中—低温热液裂隙充填成矿,成矿流体的均一温...     

从讲政治的高度严格土地管理

随着各地工业化程度不断加深,经济社会发展呈现出了新的发展态势,各地为抢项目、上项目纷纷出台了一些优惠政策,随之而来的就是大量土地被征用,大批农民失去土地,保护土地和发展经济之间出现不和谐的音符,由此引发了一连串的问题。解决因发展而带来的问题,做到发展经济与保护土地协调一致,应当做好以下几点:认真贯彻温家宝总理重要谈话及国土资源部紧急通知精神。温总理的谈话,贯穿了科学发展观和党的执政理念,准确把握了当前现实与变化趋势,提出了不少新的重要论断,内容更为丰富,要求更加严格。作为地市级政府来说最主要的就是要认真学习领…     

一种用于卫星电视时间比对的秒脉冲信号提取器

为了获得稳定、可靠的卫星电视时间比对数据,成功研制了以秒信号提取器为主要部件的新一代卫星电视时间解调器。介绍了秒脉冲信号提取器的设计原理,详细阐述了钳位电路、采样保持电路和数字延迟电路的设计思路。对采用新的解调器和采用旧的解调器的卫星电视秒信号监测系统所得到的比对数据进行了分析,结果表明新的电视时间解码器的性能得到明显提高。     

CARAIB陆地碳循环模型研究进展及其应用

陆地生态系统碳循环是全球变化研究中的重要组成部分,多种模型已用于陆地生态系统碳循环的模拟。文中着重论述了陆地生物圈碳循环模型CARAIB的原理、方法及其应用和最新进展。CARAIB模型主要是基于叶面光合作用子模型、冠层子模型和木质呼吸作用3个子模型的耦合,应用大气环流模式气候数据模拟出生态系统碳存储量和生物群区分布。介绍了欧洲利用植物数字化地理配准数据库重新划分植物群组(BAGs)的方法,比较BAGs与传统的植物功能型(PFTs)划分在方法上的差异,根据植物群组应用CARAIB模型进行生物群区分布模拟,并提出利用CARAIB模型模拟我国陆地碳循环和生物群区分布的可行性,为研究中国植被对气候变化的响应模型和预测提供区域尺度的新方法。