查询词典 edge detection

The method to configure RED parameters based on network properties is also presented. Simulations show that the modified Random Early Detection algorithm really performs better than the original Random Early Detection algorithm and can work for a much wider range of traffic. Finally, whether the assured service mechanisms i. e. an edge router tags every arriving packet of a TCP flow based service profile and core router drops packets differently at congestion using active queue management scheme is possible to provide a throughput consistent with target rate, is investigated under different network scenarios. Different factors including target rate tagged algorithm, RIO algorithm and TCP congestion control mechanism how to affect the throughput of an assured service TCP flow are examined. Based on a fluid model. we then derive a model of an assured service TCP flow, which is the function of round trip delay, packet loss rate and token bucket parameters. Based on this model, we observe that in some cases it is possible to regulate the token bucket parameters to gain a consistent throughput with the target rate, while in other cases there exist ranges of values of the achieved rate for which the token parameters have no influence. With the latter, some modified TCP congestion control mechanisms to assure TCP throughput are proposed.

最后，在区别服务网络结构内，研究了当前提出的一种边缘路由器根据服务合同标记、分类数据包，结合内部路由器采用主动队列缓冲管理机制区别处理数据包的确信服务机制是否可在不同网络情况下使TCP连接获得同目标速率相一致的、公平的吞吐量问题；指出影响TCP连接获得同目标速率相一致吞吐量的主要因素是目标速率大小、标记算法参数和TCP连接的拥塞控制算法；对此，基于流模型假设，首次推导出一个以端到端时延、数据包丢失率、漏桶参数为变量的确信服务TCP连接吞吐量模型；利用这个模型进行分析，得到主要结论是在一些情况下可通过设置合适的漏桶参数得到同目标速率更一致的吞吐量，而在另一些网络情况下不管如何设置漏桶参数都不能使TCP连接获得同目标速率一致的吞叶量；对于后一些情况，还初步讨论了改进TCP拥塞控制算法来改善TCP连接性能的方法。

Due to its stateoftheart design, high-efficiency object detection and edge detection algorithms, the outstanding performance and good reliability of this system have been fully proved in the practice for more than 2 years.

系统两年多的上线运行证明：该系统在冷轧机出口十分恶劣的环境条件下，可长期连续工作，准确高效地检出带钢孔洞缺陷，具有卓越的检测性能和良好的稳定性。

For the images of VSMCs cultured on the silicon membrane stretched by pulsatile flow, one method with eight steps based on difference arithmetic operators is proposed. Image enhancing, image graying, halation removing, Canny edge detection, mathematical morphology dilation, edge smoothing, mathematical morphological reconstruction are implemented according to the set sequence.

本文针对膜式张应力装置中体外培养血管平滑肌细胞图像，深入分析了该细胞力学实验中细胞图像的特点，提出了基于微分边缘检测算子的图像分割技术路线，依次为图像增强、灰度化、消除光晕、Canny边缘检测、数学形态学膨胀、区域填充、平滑边缘、形态学重建。

Though comparing Canny operator and center B spline dyadic wavelet, the following conclusion is proven in this dissertation: a Center B spline function has tight support and Canny operator hasn't. b Center B spline function asymptotic convergence to Gaussian function and the derivative of Center B spline function asymptotic convergence to Canny operator. c The derivative of fourth order center spline B function is more suitable as a optimal edge detector than Canny operator. d Center B spline function can balance the smoothing and approximation of original data, and the fourth center B spline function is the only optimal solution of two order smoothing problem. e The error between the valve of time-frequency uncertainty of the fourth center B spline function and the lower bound of time-frequency uncertainty does not exceed 0.143% of the lower bound. f The derivative of center spline B function can construct a stability dyadic wavelet and can give a fast algorithm for multiscale edge detection, but Canny operator can do neither.

作者给出了Canny算子与中心B样条二进小波严格的比较证明，得出如下结论：a中心B样条函数具有紧支集，Canny算子不具有紧支集。b中心B样条函数的极限收敛于高斯函数，中心B样条函数的导数收敛于Canny算子。c四阶中心B样条函数的导数比Canny算子更接近最佳边缘检测滤波器。d中心B样条函数比高斯函数更能兼顾对原函数平滑和逼近的折中要求，并且四阶中心B样条函数是二阶逼近问题的唯一最优解。e四阶中心B样条函数的时频测不准关系值与时频测不准关系下界的逼近误差不超过0.143％。f中心B样条函数的导数可以构成稳定的二进小波，存在快速的多尺度算法；而Canny算子不构成稳定的二进小波，无法给出快速的多尺度算法。

This paper studies the causes of noise sensitivity and edge coarseness using usual edge detection presently.

针对目前常用的边缘检测方法对噪声比较敏感，测得的边缘比较粗糙等现象，在传统边缘检测方法的基础上提出了一种基于数据融合的边缘检测方法。

Therefore, based on analysis the relation of edge density distribution and the ratio, an adaptive multiscale edge detection method is proposed.

基于这个比值与边缘密度分布关系，提出了基于区域能量的自适应多尺度边缘检测方法。

To improve the segmentation effection and efficiency, we fulfill the following work:There is an obvious difference between General Fuzzy Operator and other edge detection which based on edge magnitude.

本文在提高图像分割质量和效率方面做了以下几个方面的工作：基于广义模糊算子法的图像边缘检测与其它基于边缘强度依靠导数的边缘检测法明显不同，具有计算量小，检测到的边缘精度高等特点，但是GFO算法中的关键参数需经验、人为确定，影响了该方法的检测效果，限制了其在实际中的推广应用。

Next, edge detection using differential operator, edge thinning and connecting are introduced. Model and methods of image segmentation are discussed subsequently.

本文针对图像的灰度和边缘等特征，研究了微分算子边缘检测方法以及边缘细化和连接的算法，给出了图像分割的模型和灰度阈值的简单分割及自动分割方法。

According to the multi-scale propagation characteristic of image edge and noise as well as principle of edge detection using wavelet transforman,an algorithm based on cubic B-spline wavelet and directional derivative is presented.

根据图像边缘及噪声的多尺度传播特性和小波边缘检测的基本原理，提出了一种基于方向导数和三次B样条小波的边缘检测算法。

In this paper, a new edge detection method——method using extremum of first directional derivative is proposed, based upon a general gradient edge model.

文中通过傅里叶变换，在频率域，通过求垂直于边缘的一阶方向导数，并检测其极值点来确定边缘。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。