基于NetCDF数据模型的海洋环境数据三维可视化研究

针对海洋环境数据多维、多格式及动态性等特点,本文在全面分析NetCDF数据模型的原理、数据组织及其调度方法的基础上,基于大范围三维虚拟场景,设计了符合NetCDF标准典型海洋环境要素的三维动态渲染模型,实现了海洋环境要素数据的三维动态可视化表达与分析。实验表明,本文方法为复杂海洋现象的表达、变化规律分析以及趋势预测等研究提供强有力的可视化辅助工具。     

奇台县某金矿矿石特性及可选性试验研究

通过对金矿石化学及矿物组成、自然金形态、嵌布粒度、嵌布方式等深入研究,查明了该矿石性质。利用浮选法和氰化法进行可选性试验研究,浮选试验精矿品位为46.86 g/t,回收率达85.14%,氰化试验最高浸出率96.38%。综合分析认为,采用浮选法选矿较合理。     

市级国土空间规划"一张图"实施监督信息系统研究——以连云港市为例

自然资源部门为落实"两统一"职责,从国家到地方都开展了国土空间规划编制工作,并同步推进国土空间规划"一张图"实施监督信息系统建设.以连云港市国土空间规划"一张图"实施监督信息系统项目为例,构建了基于国土空间基础信息平台的系统建设框架,实现"一张图"国土空间规划编制、成果核对和审批、国土空间用途管制支持和资源环境承载能力...     

区域性CORS系统监测地表形变的可行性

连续运行卫星定位服务系统(简称为CORS)已经在国内外广泛建立,CORS在维护区域大地测量基准和城市测绘工作中得到了非常广泛的应用。但在城市地面沉降监测方面,仍存在基准站的稳定性、测量精度对平面及高程形变影响等问题。这里提出了一套完整的基于CORS系统变形监测网的稳定性分析的方法和流程。采用秩亏自由网平差,以位移向量一次性范数最小原则求取监测网点最合理的位移量及权阵。采用正态分布函数对监测点的位移显著性进行检验。结合武汉市地面沉降监测项目,分析评价了武汉市连续运行卫星定位服务系统(简称为WHCORS)用于城市地表形变监测的可行性。     

扇形划分的地面激光扫描地形点云数据化简

针对地面激光扫描仪获取的点云数据具有数据量大、冗余数据多、分布不均匀的特点,提出了一种基于扇形划分的地面激光扫描点云数据化简方法.首先根据设定的初始扇形块半径和弧长计算整个点云范围内的扇形块参数;然后再将点云按坐标分配到相应的扇形块中;最后对每个扇形块中的点采用相应的计算方法得到化筒后的点云.实验证明,该算法能够较好地...     

C#与Matlab混合编程技术在数字地震信号处理软件中的应用

Matlab软件具有功能强大的数值计算和数字信号处理功能.C序开发语言.Matlab Builder NE可以将MTALAB函数打包,供所有支持公共语言规范的.NET语言调用.为了充分利用两种语言各自的优势,结合数字信号功率谱分析实例,提出了基于.NET组件的Matlab和C#混合编程方法.该方法能够轻松实现C#环境下...     

海洋地球物理空间数据仓库系统的设计与实现

本文将空间数据仓库技术引入到海洋地球物理空间数据的管理和应用上来,探索一套适合于海洋地球物理调查和科研工作的空间数据仓库构建方法.本文重点从数据提取工具、空间数据仓库和应用服务器等几个方面对海洋地球物理空间数据仓库系统进行设计和开发,实现海洋地球物理空间数据的组织和管理,向用户提供便捷、直观、高效的面向应用主题的空间数...     

Asymmetric rainband breaking in Typhoon Haitang (2005) before and after its landfall

Using the WRF (Weather Research Forecast) model, this work performed analysis and simulation on the rainband change during the landfall of Typhoon Haitang (2005) and found that breaking may occur over land and oceans leads to distinct asymmetric precipitation. The breaking is related to the topographic effect as well as interactions between the typhoon and midlatitude systems at upper levels. During the landfall, divergent flows at the 200-hPa level of the South-Asian high combined with divergent flows at the periphery of the typhoon to form a weak, inverted trough in the northwest part of the storm, with the mid- and low-level divergence fields on the west and northwest side of the typhoon center maintaining steadily. It intensifies the upper-level cyclonic flows, in association with positive vorticity rotating counterclockwise together with air currents that travel stepwise into a vorticity zone in the vicinity of the typhoon core, thereby forming a vorticity transfer belt in 22–25? N that extends to the eastern part of the storm. It is right here that the high-level vorticity band is subsiding so that rainfall is prevented from developing, resulting in the rainbelt breaking, which is the principal cause of asymmetric precipitation occurrence. Migrating into its outer region, the banded vorticity of Haitang at high levels causes further amplification of the cyclonic circulation in the western part and transfer of positive vorticity into the typhoon such that the rainband breaking is more distinct.     

Characteristics of intensity change in tropical cyclones affecting the South China Sea from 1977 to 2007

The best track data of tropical cyclones (TCs) provided by Regional Specialized Meteorological Center (RSMC) Tokyo for the South China Sea (SCS) from 1977 to 2007 are employed to study the spatiotemporal variations (for a period of 12 hours) and the rapid (slow) intensification (RI/SI) of TCs with different intensity. The main results are as follows. (1) Over this period, the tropical storms (TSs) and severe tropical storms (STSs) mostly intensify or are steady while the typhoons (TYs) mostly weaken. The stronger a TC is initially, the more observation of its intensification and the less its variability will be; the more observation of its weakening is, the larger its variability will be. (2) The TC intensifies the fastest at 0000 UTC while weakening the fastest at 1200 UTC. (3) In the intensifying state, TSs, STSs, and TYs are mainly active in the northeastern, central-eastern, and central SCS respectively. The weakening cases mainly distribute over waters east off Hainan Island and Vietnam and west off the Philippines. Some cases of TSs and STSs weaken over the central SCS. (4) The RI cases form farther south in contrast to the SI cases. The RI cases are observed in regions where there are weaker vertical shear and easterly components at 200 hPa. The RI cases also have stronger mid-and lower-level warm-core structure and smaller radii of 15.4 m/s winds. The SI cases have slightly higher SST.     

PDSOFT三维设计软件在橇装设备上的应用

本文介绍PDSOFT三维设计软件的主要特点及在工程项目中的具体应用。采用PDSOFT三维配管设计软件设计具有配管直观、出图速度快、材料统计准确等优点,尤其进行橇装化设计时,该软件能在有限的空间里完美地实现管道的预置,弥补二维设计的缺点,是橇装化装置必不可少的设计手段,另外三维设计可在装配现场预制管道,提高工作效率,缩短建设周期,具有显著的经济效益。