基于VB和OpenGL的工业测量数据可视化技术研究

在工业测量领域中,由于测量对象千差万别,离散的测量数据很难进行描述和分析,而可视化技术能有效地克服这一缺点。本文研究了在VB平台上进行OpenGL图形开发的方法,实现了DXF文件的读取与显示、多种3维模型的绘制以及交互操作功能,为工业测量数据实现3维可视化分析提供了一个方便、快捷、高效的途径。     

海洋环境观测技术研究进展

回顾了近年来海洋观测技术发展的基本情况和主要成果,同时指出了海洋观测技术的局限性,与数值模拟技术相结合的必要性,以及加强发展海啸、风暴潮和孤立内波等灾害性强海洋动力过程的监测技术和预警研究的迫切性。     

基桩缺陷逐步能量恢复递推定量分析

通过大量正演计算,对不同桩周土条件下缺陷程度与时域速度响应波形中入射波波幅与反射波波幅的比值进行了相关性分析,拟合出桩侧土为粘土、砂土、粉土条件下桩径变化程度与波幅比之间的关系式。通过理论分析,在基桩存在多缺陷时,导出了缩颈与扩颈对下一个缺陷引起的反射波幅值的影响系数,进而,提出了逐步能量恢复递推缺陷程度的理论与方法,在时间域中,实现了基桩存在多缺陷时的低应变动测缺陷量化分析。模型桩试验分析结果表明,缺陷量化分析方法可取得显著效果。     

Freshwater flocculation of suspended sediments in the Yangtze River, China

This study focuses on suspended sediments and in situ flocculation in the Yangtze River, with the goal of improving our understanding of the relationship between freshwater and estuarine flocculation. A field survey with state-of-the-art instruments was carried out in January 2008 in the reach from downstream of the Three Gorges Dam to the estuary. The data show that in situ floc mean diameters range from 22 to 182???m in the river, whereas the median dispersed grain sizes are 4.4?C11.4???m. This demonstrates that flocculation is an important process during the transport of suspended sediments along the river. The flocculation characteristics, suspended sediment concentration and dispersed grain sizes all vary longitudinally in the main stream of the Yangtze River. Biochemical factors are likely be more significant in the freshwater flocculation than in the estuary, where hydrodynamics and biochemical factors are both important. Flocculation is found in the freshwater river, in the estuary and in coastal waters, which indicates that dynamic break-up/reflocculation processes take place during the suspended sediment transport. The freshwater flocs may behave as parent flocs to the estuarine flocculation. This study enhances our understanding of flocculation from estuarine and coastal areas to fresh river systems and provides insights into the effects of input of riverine flocs to the estuarine flocculation and into the sources and fate of flocs.     

基于GoogleSketchUp的3DGIS建模技术研究与应用

分析了GIS三维模型的特点,阐述了GIS三维建模原理及流程,在VisualC#．Net平台下,利用GoogleSketchUp实现了三维场景的可视化和查询功能。     

Characteristics of particle size for creeping and saltating sand grains in aeolian transport

Creep and saltation are the primary modes of surface transport involved in the fluid‐like movement of aeolian sands. Although numerous studies have focused on saltation, few studies have focused on creep, primarily because of the experimental difficulty and the limited amount of theoretical information available on this process. Grain size and its distribution characteristics are key controls on the modes of sand movement and their transport masses. Based on a series of wind tunnel experiments, this paper presents new data regarding the saltation flux, obtained using a flat sampler, and on the creeping mass, obtained using a specifically designed bed trap, associated with four friction velocities (0·41, 0·47, 0·55 and 0·61 m sec^?1). These data yielded information regarding creeping and saltating sand grains and their particle size characteristics at various heights, which led to the following conclusions: (i) the creeping masses increased as a power function (q = ?1·02 + 14·19u_*³) of friction wind velocities, with a correlation (R²) of 0·95; (ii) the flux of aeolian sand flow decreases exponentially with increasing height (q = a exp(–z/b)) and increases as a power function (q = ?26·30 + 428·40 u_*³) of the friction wind velocity; (iii) the particle size of creeping sand grains is ca 1·15 times of the mean diameter of salting sand grains at a height of 0 to 2 cm, which is 1·14 times of the mean diameter of sand grains in a bed; and (iv) the mean diameter of saltating sand grains decreases rapidly with increasing height whereas, while at a given height, the mean diameter of saltating sand grains is positively correlated with the friction wind velocity. Although these results require additional experimental validation, they provide new information for modelling of aeolian sand transport processes.     

城镇地籍测量实施方案探讨

以地籍测量为研究对象,阐述了现代地籍调查的特征,结合湖北省安陆市城镇地籍调查项目的实际工作和成功经验,对地籍调查工作进行了各个方位的理性分析,提出了现代地籍测量完善可行的工作实施方案,较好地解决了地籍调查工作中的一些实际矛盾。并对实施方案中如何提高工作效率进行了有益的探讨。     

三分量地震资料中各向异性检测

各向异性研究是当令地震学研究领域中重要课题之一；三分量地震资料中各向异性的检测是各向异性理论研究成果解决地球科学实际问题的重要桥梁。本文简要描述了各向异性介质中横波分裂现象，分别介绍了现有的四种主要检测技术，即偏振图法、协方差拒阵法、质，点振动分辨率法及传输矩阵法，并对这四种技术作了一定的评述。