值分布

It is the first important step in video analysis and will directly affects the effectiveness of indexing Shot boundary detection is one of our major research interests and we will tackle the following existing problems the ambiguity between gradual change and camera motion, the discontinuity during gradual change, false detection caused by illumination variation and flashlight, automatic threshold selection Firstly, we discuss shot boundary detection in non-compressed domain In chapter 2, we compare some of the commonly used detection methods which are based on frame difference and point out that single feature will not generate good results As a conclusion, we use fuzzy logic to combine multiple features Presently, most frame difference based shot boundary detection algorithms rely on threshold and hence the selection of such thresholds will greatly affect the performance of boundary detection We propose a membership function to define frame difference and calculate the membership with self adaptation according to the statistic distribution of frame differences to satisfy different type of video clips Experiments show that the proposed fuzzy shot boundary detection algorithm can be used with different video types and has a high detection precision and recall In chapter 3, we discuss model-based shot boundary detection algorithms regarding chromatic and spatial editing effects such as fade-in, fade-out, dissolve and wipe Various parameters are proposed to better describe the characteristics of each editing type.

镜头边界的检测是把视频自动地分割为一个个镜头，作为基本的索引单元，因此它是视频分析重要的第一步，直接影响到视频检索的成败。镜头边界的检测是本文研究的重点之一。目前镜头边界检测算法主要存在以下问题：渐变与镜头运动难以区别；渐变过程中的不连续与停顿、光照条件的变化及闪光灯等特殊情况会引起误检测；自动选择阈值比较困难等。本文首先针对非压缩域视频进行了镜头边界检测的研究。在第二章中我们采用了比较流行的基于帧间差的方法。在比较各种帧间差计算方法的基础上，指出使用单一的特征难以取得很好的检测效果，提出用模糊逻辑综合使用各种特征。目前大多数基于帧间差的镜头边界检测算法都采用阈值法进行镜头转换的判别。阈值选择的误差对检测性能有较大的影响，本文提出用隶属度函数定义帧间差较大、中等较大和较小等概念，并根据帧间差的统计分布自适应地确定隶属度，以适应不同类型的视频片断。实验结果表明这种基于糊逻辑的镜头边界检测算法可以适应不同的视频，并具有较高的检测精度和检出率。在第三章中采用基于模型的方法进行镜头渐变的检测，研究了淡入／淡出、慢转换和扫换的模型。

Integrated with the calculation methods of soil pressure, the mechanism of soil pressure of fale is studied systematically and detailedly based on the mode of axial stress distribution of wholly grouted anchor.

在全长粘结式锚杆拉力分布模型基础之上，结合本文的土钉土压力计算方法，本文对面层土压力机理进行了系统详细的研究，提出了面层局部土压力、面层土压力及土钉最大拉力的计算公式和分布模型，理论分析和实例分析表明，本文提出的轴力分布模型和面层土压力机理是合理的，解决了面层土压力取值标准问题，为面层设计提供了定量的依掘，土钉最大拉力可直接用于土钉长度设计。

Firstly, those useless to classify texts are filtered according the category document frequency distribution difference of each feature; and then in order to overcome the limitations of TF-IDF weighting formula a novel weighting formula called TF-CDF is presented . Calculate the weight of each feature according to TF-CDF and build the Vector Space Model for the entire corpus. To select significant features, a feature selection approach based on Variable Precision Rough Set is also proposed and implement with some SQL sentences combining the definitions of VPRS with the advantages of SQL sentences.

该文首先根据特征词的类别分布差异进行特征过滤；然后，分析传统的权值公式TF-IDF的缺点，采用改进的权值计算公式简记为TF-CDF，依据TF-CDF公式计算每个特征词的权值，生成文档集的向量空间模型VSM；接着，提出了一种基于可变精度粗糙理论的特征选择进一步选择对分类贡献度大的特征，并用SQL实现。

For reducing boundary distortion area, the elevations of grid DEM are viewed as a discrete sequence under a generalized coordinate, so that the boundary problem of two-dimensional discrete wavelet transform is turned into the boundary problem of one-dimensional discrete wavelet transform, which not only greatly reduces the boundary distortion area, improves the precision of reconstructed DEM data near the boundary, but also decreases the number of zeros adding on the boundary for wavelet transform, and boosts the compression ratio. On the basis of analyzing the distribution characteristics of coefficients in low and high frequency bands, a mixed entropy coding plan is applied, and a high efficient quantizator called"self-adaptive hard threshold"is established, which is helpful for improving the precision of the reconstructed DEM data and for enhancing compression ratio.

为了减小小波变换山区格网DEM数据压缩中边界失真区域，将山区格网DEM高程值视为广义坐标下的离散随机序列，把二维离散小波变换中的边界问题转换为一维离散小波变换中的边界问题，不仅大大减少了小波变换边界失真区域，提高了重构DEM数据边界点的精度，而且减少了边界补零个数，提高了压缩比；通过对山区格网DEM数据小波变换低频区和高频区变换系数分布特点的分析，采取了霍夫曼—游程混合熵编码方案，设计了高效、低失真的"自适应硬阈值"量化器，即对低频区变换系数不进行量化，直接进行霍夫曼编码；对高频区变换系数则先用"自适应硬阈值"方法量化处理，再进行游程编码。

Through the improvement of the existing model,the Gaussian distribution of the residual error is supplanted by the Laplace distribution in order to approach the real distribution.

通过对已有模型进行改进，用拉普拉斯分布代替插值点残留误差的正态分布，使分布情况更符合实际。

Second, when the error distribution of the model is the Laplace distribution, the L1 estimation of 1-D location estimation is essentially the sample median, hence the study of the Laplace distribution is also important.

第二，由于当模型的误差分布是拉普拉斯分布时，一元位置的最小一乘估计是样本中值，因此对于拉普拉斯分布的研究也是至关重要的。

Study of segmentation of surveillance objects with motionThe camera noise statistical characteristic is approximated as Gauss or Laplace distribution, then an error probability is set and a threshold is determined. According to the hypothesis test theory, a constructed statistic can judge whether an object is moved or not.

二、以运动物体作为监控对象的分割研究将噪声分布近似为Gauss分布或Laplace分布，再设定误判概率进而确定一个阈值就可以利用假设检验的思想，构成统计量对不同对象判断其运动与否。

Based on analysis and certification of a large number of measured data of different channels and different discharges, it is shown that weather theoretical form or measureds results of lateral velocity distribution are consistent with the laws of logarithmic distribution.

大量不同梯拱形渠道、不同流量的流速实测数据分析和验证表明，理论与实测流速横向分布都符合对数分布规律，利用多变量回归分析，确定了流速横向分布系数a、b值。

The structure and heterogeneity of urban green space in the five districts in Fuzhou , which included the main tree species with diameter at breast height distribution, height class, health class, importance value, relation and the green space patches with areas distribution, perimeter distribution, porosity, connectivity, marginal density, dominance, the characteristics of geo-statistics and so on, were studied in quantification by the use of the principle of landscape ecology combining with the method of studying porosity and connectivity and geo-statistics.

本研究应用景观生态学的原理结合孔性、连通性研究方法和地统计方法对福州市五个行政区的绿地结构和异质性进行了量化研究，包括：城市绿地主要树种、树种的胸径分布、树高等级、健康等级、重要值和多样性、主要树种间的关联度以及绿地斑块大小分布、周长分布、斑块的孔性、连通性、边缘密度、优势度、斑块的地统计学特性等。

A robust wavelet threshold based on the minimax description length principle is derived in the ε-contaminated normal family for maximizing the entropy.

针对雷达信号中存在的不同于高斯分布的拖尾分布噪声，基于ε污染的正态分布族获得一种鲁棒阈值处理方法。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。