包含圆形的单幅图像距离量测

提出了两种基于圆形的单幅图像平面几何量测方法。第一种算法首先计算出与待测对象平行的直径,然后获得圆形所在平面上任意两点之间的距离。受待测线段位置、方向等影响,量测结果的精度各向差异大。第二种算法首先求取圆形的外接正方形,将问题转化为包含正方形的平面距离量测。模拟图像与真实图像的测试结果表明,第二种算法的量测精度更具有稳定性。     

集成距离变换和区域邻接图生成Delaunay三角网的方法研究

基于距离变换和区域邻接图,提出了一种D-TIN(包括约束的D-TIN)的生成方法。利用D-TIN是Voronoi图的几何对偶这一特性,使用距离变换获取点的Voronoi图,使用区域邻接图获取点在该Voronoi图上的空间邻接关系,以生成D-TIN或者约束的D-TIN。实验表明,与经典的基于数学形态学生成的D-TIN和约束D-TIN的方法相比,本文算法可以分别提高约57.70%和56.64%的效率。     

定向越野非体育教育专业组女子短距离赛研究——以云南省为例

采用文献资料、OCAD（定向运动制图）软件路线分析和China heath定向运动计时系统法。以2011年云南省第6届大学生运动会定向越野非体育教育专业组女子短距离赛决赛前8名运动员比赛时间为研究对象。分析运动员在分段时间中的技能执行能力,结果显示：运动员之间体能差距主要呈现3个层次、比赛结果竞争激烈,比赛时间差距明显;技能训练安排不够系统、运动员选材范围受到局限,缺乏高水平的定向运动队员;运动员对偏向瞄准技术尚未完全吃透、简化读图技术不能准确把握;缺乏高水平的教练员队伍;缺乏高水平的且具有实践经验的教练员队伍。     

倾斜观测载荷干扰源最小"安静"距离理论分析

作为一种高精度的形变观测,钻孔倾斜观测点必须尽可能避开干扰源。河流、湖泊、仓库(货场、列车编组站)和铁路,是几种主要的影响钻孔倾斜观测的地面载荷变化干扰源。中对这些地面载荷变化干扰影响分别建立了不同的模型,提出了针对一定的干扰限定指标,估计观测点到干扰源的最小“安静”距离的方法。     

The utility of travelling when destinations are heterogeneous. How much better is the next destination as one travels further?

In many studies travel behaviour (for example, commuting) is analysed on the basis of a utility function with the distance (d) travelled as one of the arguments. An example is U=U(d,Y-cd,T-td) where Y and T denote money and time constraints, and c and t money and time costs per unit distance. This standard approach is not without problems, however, since it ignores the fundamental fact that most transport has a derived character: travelling kilometres is not an activity that gives utility per se, but only because these kilometres bring people to certain places they want to visit. In this paper we develop a method that provides a justification for utility functions such as shown here by showing that these can be made consistent with theories that take into account the derived character of transport.     

Computational Methods for the Determination of Roundness of Sedimentary Particles

A number of subjective and objective methods have been proposed to determine the roundness of rock particles, roundness being one of three properties describing the shape of a particle. Methods that make use of the Fourier transform of the polar coordinates of particles’ edge elements are proposed in this paper. Lowpass filters are used to smooth the profiles of rock particle, roundness is then determined from the differences between the original and smooth profiles. Further methods that are proposed make use of different measures of inequality to quantify the distribution of the energy among the transform coefficients of the profiles of rock particles. These values are then used to determine the roundness of the particles. Entropy and Emlen’s modified entropy are the measures of inequality that are used. Different methods of determining the centre point of a particle and different methods to interpolate the edge elements are compared. The sensitivity of the methods to different resolutions is also investigated. The results obtained with the proposed methods are comparable to those obtained with an existing Fourier transform based method, however it is shown that the proposed methods are computationally less demanding. It is also shown that the proposed methods are better than the existing method when the comparison is based on the correlation between the mean roundness of samples of particles and the actual roundness of the particles.     

大型变电站厂址的地震地质条件研究——四川省石棉地区变电站遴选实例

地震灾害对工程场地的影响主要体现在3个方面，一是地震断层直接造成地面的断错：二是强烈的地面地震动；三是地震引起的地质灾害如滑坡、泥石流或砂土液化等。本文结合在四川省石棉地区大型变电站厂址的遴选实例，说明详细研究厂址附近断层的活动习性及其空间分布位置是研究大型变电站厂址地震地质条件的关键性因素。     

On the Use of Non-Euclidean Distance Measures in Geostatistics

In many scientific disciplines, straight line, Euclidean distances may not accurately describe proximity relationships among spatial data. However, non-Euclidean distance measures must be used with caution in geostatistical applications. A simple example is provided to demonstrate there are no guarantees that existing covariance and variogram functions remain valid (i.e. positive definite or conditionally negative definite) when used with a non-Euclidean distance measure. There are certain distance measures that when used with existing covariance and variogram functions remain valid, an issue that is explored. The concept of isometric embedding is introduced and linked to the concepts of positive and conditionally negative definiteness to demonstrate classes of valid norm dependent isotropic covariance and variogram functions, results many of which have yet to appear in the mainstream geostatistical literature or application. These classes of functions extend the well known classes by adding a parameter to define the distance norm. In practice, this distance parameter can be set a priori to represent, for example, the Euclidean distance, or kept as a parameter to allow the data to choose the metric. A simulated application of the latter is provided for demonstration. Simulation results are also presented comparing kriged predictions based on Euclidean distance to those based on using a water metric.     

长距离自流型渠道输水控制的二步法研究

提出了一种针对自流型渠道输水的最优化控制的两步法。第一步是控制各闸站流量使渠段水位(或蓄水量)达到目标水位(或蓄水量),第二步是调整流量使渠段水位稳定。建立了使渠道内水流在最短时间内恢复到正常运行水位的最优渠道输水控制模型。构建了长距离渠道输水控制的一系列约束条件,包括渠道下游需水量约束、最高控制水位、水位最大容许下降速度、渠道容许过流能力、最少的开机次数等。提出了利用线性规划或将大系统分解为若干子系统求解的方法。算例结果表明,用传统的渠道控制方法需要几天才能使水位恢复到目标水位的渠道,用本优化方法控制,可以在几小时内使渠道水位达到目标水位并达到稳定。     

全球位系数模型构建高精度局部重力场的Clenshaw求和

给出了勒让德函数4种模式的Clenshaw求和公式,在此基础上得到由全球位系数模型计算重力场参数的二阶Clenshaw求和公式,分析了EGM96与WDM94应用于某试验测区局部重力场的精度,为该测区在构建高精度局部重力场时初始全球位系数模型的选取提供了借鉴。