查询词典 threshold

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。

From this model, we can find how the channel length, channel doping concentration, the thickness of silicon film and gate oxide influences the threshold voltage, and the variation of threshold voltage is independent on back-gate bias.

从模型中可以容易地分析阈值电压与沟道浓度、长度、SOI硅膜层厚度以及栅氧化层厚度的关系，并且发现△V与背栅压的大小无关。

After studying the characteristics of Particle Swarm Optimization,Particle Swarm Optimization is used in wavelet domain to optimize the thresholds,and garrote shrinkage function is used to process wavelet decomposition coefficients,which overcome the shortcoming of discontinuity of hard-threshold and decreased the fixed bias of soft-threshold.

研究粒子群优化算法的特性，将其应用于小波域，对阈值进行寻优，并使用garrote阈值函数量化小波分解系数，而garrote阈值函数既克服了硬阈值函数的不连续性，也减小了软阈值函数存在的恒定偏差。

The energy distribution of the focused laser spot has Gaussian profile, and if the exposure dose threshold of the photoresist is less than and far away from the peak of that Gaussian curve, the linewidth will be less affected by the variation of exposure dose or exposure dose threshold, and so, will improve the linewidth stability.

准直光束经物镜会聚后光斑的能量呈近似高斯分布，当胶层的曝光量阈值远离高斯型曝光量曲线的头部时，可以弱化线宽对实际曝光量或胶层曝光量阈值等变化的敏感度，从而提高线宽的稳定度。

In a threshold signature scheme, a group signature is generated by a number of participating members, which is larger than or equal to a predefined threshold value.

在一个门限签名方案，群签名是产生了一些与会成员，这是大于或等于一个预定义的阈值。

The macular threshold and FM 100-hue test in 46 patients with normal vi- sion in one eye and suffering from AMD in the fellow eyes, and 46 age-matched normal subjects were observed with FM 100-hue test、Macular threshold program of Humphrey field analyzer and Amlser gride test.

八、单侧老年性黄斑变性对侧眼的黄斑阈值及FM100-色调试验检测采用FM100-色调试验仪、Humphrey视野分析仪黄斑阈值程序Amsler表对46例单侧AMD对侧眼和46只眼年龄相匹配的正常对照组进行检查。

Secondly, this thesis simulates CDMA Soft Handoff by using Hata transmition model and the threshold parameters on Visual C++ platform. Then through relevant experiments, it validate the impact of CDMA system threshold parameters in switching.

通过对软切换的分析，利用Hata传播模型和切换规则设置相关门限参数并在Visual C++平台上实现软切换的仿真设计，并通过相关实验，验证了CDMA系统中软切换各项参数取值对CDMA切换产生的影响，能够仿真CDMA切换功能。

Results According to the experience, the enhancement threshold of aorta, portal vein and hepar were set at 70 HU. The onset and ending time of enhancement threshold were found.

结果根据经验确定主动脉、门静脉及肝实质的增强阈值为70HU，并找到增强阈值达到和结束的时间。

The experiments indicate that adding phonon blockcer to the transmission fiber is helpful to improve the SBS threshold, and the blocker at different locations makes different effects. In a 60 km testing fiber, the SBS threshold is the maximum when we insert the blocker at the point of 30 km.

研究结果表明，在光纤线路中加入声子阻塞器可以提高SBS阈值，而且在光纤的不同位置的阻塞器对SBS影响有所不同，在被测的60 km光纤上起点30 km处插入阻塞器时的布里渊阈值最高。

Based on the principle of Otsu method with maximum variance between threshold algorithm of image segmentation, an improved method derived from Otsu algorithm is put forward, which combines interclass distance with intraclass distance, a partial recursive algorithm is used to search optimum threshold.

基于最大类间方差阈值图像分割算法的基本原理，然后结合目标与背景两类之间间距和类内距离对图像分割效果的影响，提出了一种改进的最大类间方差法，运用递归思想局部搜索图像的最佳阈值。

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。