光滑地表面毁伤检测方法研究

光滑地面毁伤程度评估非常重要,目前评估方法主要是基于光学图像,可是在恶劣的气候或环境条件下,很难获得光学图像,合成孔径雷达（SAR）克服了这个缺点. SAR图像是地表结构和电特征等地球物理参数的映射,通过SAR图像反演地表结构参数,可以推测出光滑地面毁伤程度. 本文以几何光学模型（GOM）为基础,建立神经网络反演模型,以获得光滑地表面受损后的粗糙度参数：表面均方根高度（σ）和表面相关长度（l）,并进一步评估光滑地表面受损程度. 实验结果表明该方法可行.     

天气雷达数字化回波图的平滑处理

首先阐述了各种图象平滑处理方法的特点，在仔细分析天气雷达数字化回波图特征的基础上，采取快速中值滤波的方法平滑天气雷达回波图，并得到了满意的结果     

我国东南部地形对降水量分布的气候影响

利用１９５１－１９８０年地面测站网的年、月平均降水量资料，分析出我国东南部地区的地形对降水量分布存在着气候影响。其影响表现在浙闽山区的东西两侧山坡各有一条多雨带，南岭南北两侧山坡附近各有一个多雨区。从这些多雨带和多雨区出现的季节清楚地呈出出地形的向风坡在多雨带和多雨区形成中的作用。指出这些多雨带和多雨区是由地形对降水天气系统影响产生的向风坡多雨带。     

光滑海面上风、温、湿廓线的层结订正模式及海气整体交换系数

详细介绍了光滑面标量粗糙度ＺＴ,Ｚｑ与风速粗糙度Ｚ０的相似表达式,论述了把Ｍｏｎｉｎ－Ｏｂｕｋｈｏｖ相似理论推广到光滑面上湍流气层的合理性,从而得到光滑面风、温、湿层结订正廓线与粗糙面廓线相统一的形式。总结了用该模式处理的三个海上梯度观测资料的计算结果,揭示出了微风时通过光滑海面的海气通量及整体交换系数受层结影响远大于风速影响的特征。并给出光滑界面上不同层结的整体交换系数随风速变化的拟合公式。     

井岗山市井岗冲水电站进坝公路隧道掘进技术成果述评

井岗山市井岗冲水电站进坝公路隧道是湖南省地质矿产局四一队施工的第一个大断面掘进工程。施工中,四一四队打破常规,积极推行“新奥法”,采用光面爆破和锚喷支护技术,成功地突破了419m破碎地层掘进的技术难关;同时,在出口段采用缝管式锚杆临时支护等措施进行浅埋破碎区段处理,为浅埋破碎地层的临时支护开辟了新途径。     

The fractal geometry of the soil—covered landscape

The soil-covered landscape surface can be idealized from two viewpoints. The intuitive view is of a smooth, absolutely continuous surface with continuous contour lines and measurable in integral dimensions. The alternative view emphasizes the roughness, a surface of little regularity and at the limit of no contours, the appropriate measure being that of fractional Hausdorff dimension. Regularity is a local property and both idealizations need to stop far short of the limit to avoid awkward consequences. The dichotomy of viewpoint can be matched in the theory of Gaussian random fields. These, if they are smooth, are very smooth but if they are irregular they are highly irregular (erratic); there is no middle ground. This Belayev dichotomy is defined and both modes applied to the soil-covered landscape. On the one hand, if the landscape is subject to a general diffusive type degradation or more generally a Davisian downwasting regime then the curvature of the landscape surface is progressively straightened and the distribution of gradient (increments) along a typical traverse will eventually adopt a Gaussian form. Then from the irregular viewpoint the surface is ultimately well represented by a fractional Brownian surface of low Hausdorff dimension (2·0 < dim < 2·3). The Hausdorff dimension is directly related to the entropy of the landscape and as degradation proceeds both quantities decrease in value. On the other hand, if the surface is regarded as smooth and well represented by an absolutely continuous Gaussian field then the mean value of the number of upcrossings of a level or the extent of an excursion set will also be Gaussian. This analysis is restricted to one dimension; the number of times a profile curve crosses or the amount of time it spends above any given level. Predictions from both viewpoints are substantially corroborated in a map analysis of 15 sites on varied terrains in Southern England and the map analysis checked against one based upon digital tape data for one of the sites.     

不同集合的球面矢量Voronoi图生成算法

分析现有球面VORONOI图生成算法的不足,介绍球面不同集合V图的定义,在此基础上提出球面偏置曲线的概念并总结了它的性质,具体分析不同集合在球面上的偏置结果及处理方法,提出基于球面偏置的多集合V图生成算法,通过实验检验算法的正确性与效率,最后得出结论和进一步的研究方向。     

1991 年江淮流域暴雨中不同尺度系统的相互作用

通过对1991年7月1～5日东亚地区网格点资料平滑滤波，将大气运动分解为大尺度背景场和中尺度扰动场。采用p坐标中湿大气动力学方程组，在两层模式中得到含有不同等压面、不同尺度系统非线性相互作用的方程组。经过简化，得到表征低层约700 hPa中尺度系统发展的物理量。低层系统的发展和衰减决定于该物理量的正负，也就是决定于200、500、700 hPa各等压面不同尺度的运动场、涡度场和温度场之间的相互作用。     

Bottom friction caused by boundary layer streaming beneath random waves for laminar and smooth turbulent flow

The effect of boundary layer streaming on the sea bed shear stresses, beneath random waves, is investigated for laminar flow as well as smooth turbulent flow. It is demonstrated how bottom friction formulas for regular waves can be used to obtain the bed shear stresses resulting from steady streaming under random waves. As a result, friction factors for steady streaming under random waves are provided, and the effect of streaming versus the effect of linear waves is discussed. For laminar flow the effect of second order Stokes waves is also included. Examples are included to illustrate the applicability of the present practical method, and results are obtained using data typical for field conditions.     

基于温特斯法的夏季气温预测模型建立及应用

介绍了温特斯法的基本理论及3个平滑方程的递推公式、初始值公式和预测模型公式，并依据其理论，采用VB6．0编程技术，设计了预测模型软件；同时，将夏季6、7、8月的月平均气温看作具有随机性、线性、季节性变化的时间序列，利用商丘、民权、柘城、永城4个代表站1961～1999年夏季气温样本资料，建立了预测模型。对2000～2002年夏季气温试报结果为，平均预测准确率92％，其中7月份100％，6月份92％，8月份83％。