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1.
目的 传统的基于欧氏距离的复杂网络表示方法容易受形状的非刚性变形影响。鉴于此,提出一种基于复杂网络模型与相对一致性距离相结合的形状特征提取方法。方法 首先,提取形状的边界轮廓点作为网络的节点,利用节点间的相对一致性距离作为边的权值构建初始的复杂网络模型;然后,利用阈值演化方法对初始网络模型进行动态演化,得到一系列子网络;最后,提取不同演化阶段下子网络的拓扑特征,实现对形状特征的提取。结果 分类和检索实验结果表明,相比于传统的复杂网络描述方法,本文方法对形状图像具有更强的描述和识别能力。结论 相比于传统的距离度量,相对一致性距离对形状的非刚性变形具有更强的稳定性。  相似文献   

2.
洪睿  康晓东  李博  王亚鸽 《计算机科学》2018,45(Z11):244-246
文中提出了一种基于复杂网络的图像特征描述方法。将图像的关键点作为复杂网络节点,利用最小生成树分解法完成初始网络的动态演化过程,由不同演化阶段下的复杂网络特征实现对图像的形状描述;根据图像像素和周围邻域的距离与灰度的相似度,由不同的阈值生成度矩阵,统计不同阈值下网络节点的度分布,完成图像的纹理描述。实验证明,该算法具有较强的鲁棒性和旋转不变性,并且在分类实验中也有较好的表现。  相似文献   

3.
随着网络规模的增加,路由节点之间有着较大的随机分布性,节点之间难以建立精确的定位模型,基于特征匹配的传统方法在故障定位节点中难以体现其随机性的特点,从而造成故障的位置不准确。论述了随机网络的定义与特性、随机网络的度分布和特征谱;通过定义随机网络的直径和平均距离,计算随机网络的集聚系数,提取随机网络故障特征的有效参数,建立故障数据的特征模块,把随机行走网络节点故障检测算法的故障特征点作为登记点,对一个节点发生故障时产生的随机种子进行初始检测,再用故障特征和随机变化检测相结合的方法,提高检测的效率。仿真结果表明,改进的方法可以提高故障节点定位的精确度。  相似文献   

4.
为了深入理解供需网络的演化规律,在研究了已有的复杂网络演化模型所刻画供需网络生长过程不足的基础上,提出了以ER网络模型表示初始网络,并在局域世界中选择新增节点的连接边,依据节点之间的网络路径值作为局域世界选取的原则,局域世界的规模可动态增长。在考虑网络生长的同时,也考虑到网络内部边的动态演化以及节点的退出问题,据此建立了供需复杂网络的有增有减的动态演化模型,并给出了生成模型的算法。仿真结果表明,该模型所生成的网络模型具有无标度特性、小世界性和高聚集性。  相似文献   

5.
陶少华  张向群 《计算机工程》2012,38(1):197-198,214
现实中有些复杂网络并不具备无尺度网络的偏好连接特性,但节点之间具有信息传递相似性。为此,研究基于自相似特征形成的复杂网络,提出一种具有自相似特征的网络演化模型。证明以节点自相似演化的网络具有自相似性,并以容量维数作为衡量尺度,揭示复杂网络的自相似性。理论分析及仿真结果表明,该模型能合理描述现实中复杂网络的演化及其特征。  相似文献   

6.
布尔分割环是设计特征在边界模型上造型的痕迹,其自动识别是后续设计特征自动重构的基础.在对特征造型过程形状演化分析基础上,提出一种布尔分割环几何表示和自动识别构建方法.首先依据边界的凹凸特性及顶点的邻接特性构建边界模型的特征顶点邻接图,并对邻接图开展顶点节点树搜索;然后将搜索方法分为初始节点选择、节点增长、搜索评估和反向传播4个步骤,在节点增长步骤中,采用相邻节点到特征面距离最小判定方法及顶点虚拟邻接构成伪边的方法,实现分割环的封闭和特征面的有效分割.实例结果表明,该方法能够从复杂特征相交形成的交线中自动识别和构造出布尔分割环.  相似文献   

7.
为了深入理解供需网络的演化规律,研究了已有的复杂网络演化模型刻画供需网络生长过程的不足,提出了以星型网络表示初始网络,在局域世界中选择新增节点的连接节点,局域世界的选取,采用了依据节点之间的网络路径值作为选取局域世界的原则,同时定义了局域世界的规模动态增长,从而建立了复杂供需网络的动态演化模型,并给出了生成模型的算法。该模型在考虑网络动态增长的同时,也考虑到网络内部边的动态演化以及节点的退出,这与现实情况相吻合,因此更细致、真实地刻画了供需网络的动态演化特性。仿真结果表明,该模型所生成的网络模型具有无标度特性和小世界性。  相似文献   

8.
王斌 《软件学报》2016,27(12):3131-3142
将目标形状的轮廓看成一个无序的点集,从中抽取形状特征,用于快速而有效的目标识别是形状分析任务中的挑战性问题.针对该问题,提出了一种基于复杂网络模型的形状描述和识别方法.该方法提出用一种自组织的网络动态演化模型构成一个分层的描述框架,在网络动态演化的每一个时刻,对网络分别进行局部测量和全局测量,抽取网络的无权特征和加权特征.在形状匹配阶段,用获得的局部描述子和全局描述子分别进行局部匹配(基于Hausdorff距离)和全局匹配(基于L1距离),组合两种匹配的距离值构成对形状的差异度度量.用标准的测试集对所提出的方法进行性能测试,实验结果表明,所提出的算法能够快速而又鲁棒地完成较高精度的形状识别任务.  相似文献   

9.
作为复杂网络研究的热门方向,有向网络链路预测旨在挖掘网络中未知的连边。网络演化机制是许多链路预测方法的理论来源和依据。现有有向相似性指标计算节点间存在连边的可能性时,忽略了实际网络演化过程中节点自身拓扑稳定性和网络结构稳定性。基于此,提出了基于拓扑稳定性的预测方法。该方法首先计算趋于稳定的节点对之间的相似度,然后计算预测节点对之间的拓扑稳定性。在三个衡量标准AUC、precision和排序分下,九个真实网络中的实验分析表明,提出方法具有较高的预测精度。  相似文献   

10.
针对主动轮廓模型图像分割,提出一种改进算法。该算法首先选取边界内部点为轮廓初始点,再根据能量与面积的关系,将传统算法中初始点向边界点收缩改进为由初始点向边界点膨胀。算法的实现采用原始模型和改进模型相互交替的贪婪算法,保证了模型的稳定性特点。实验结果表明:这种由内向外的分割算法比传统模型分割效果好及适用范围广;避免了传统模型对凹陷区域分割效果不理想及边界外部复杂环境对分割效果的影响。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。  相似文献   

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