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1.
Middle matching mining algorithm 总被引：1，自引：0，他引：1
郭平 《重庆大学学报(英文版)》2003,2(2)
1. Introduction With the increase in the amount of information, we feel the pressure from 搕he exploring information? and find that we are in a dilemma of having huge data but with little knowledge [1]. Data mining is an effective method to help us to get rid of the morass, and is a process of inferring knowledge from such huge data. A sequence is an ordered list of transactions (or itemsets), in which each transaction is a set of items. Typically there is a transaction-time associated with ea… 相似文献
2.
In this paper, the authors propose a refined Branch-and-Bound algorithm for affine-transformation based image registration. Given two feature point-sets in two images respectively, the authors first extract a sequence of high-probability matched point-pairs by considering well-defined features, Each resultant point-pair can be regarded as a constraint in the search space of Branch-and-Bound algorithm guiding the search process. The authors carry out Branch-and-Bound search with the constraint of a pair-point selected by using Monte Carlo sampling according to the match measures of point-pairs. If such one cannot lead to correct result, additional candidate is chosen to start another search. High-probability matched point-pairs usually results in fewer loops and the search process is accelerated greatly. Experimental results verify the high efficiency and robustness of the author＇s approach. 相似文献
3.
An efficient enhanced k-means clustering algorithm 总被引：9，自引：0，他引：9
FAHIM A.M SALEM A.M. TORKEY F.A. RAMADAN M.A. 《浙江大学学报(A卷英文版)》2006,7(10):1626-1633
INTRODUCTION The huge amount of data collected and stored in databases increases the need for effective analysis methods to use the information contained implicitly there. One of the primary data analysis tasks is cluster analysis, intended to help a user understand the natural grouping or structure in a dataset. Therefore, the development of improved clustering algorithms has received much attention. The goal of a clustering algorithm is to group the objects of a database into a set of m… 相似文献
4.
冼军 《浙江大学学报(A卷英文版)》2005,6(7):760-763
In this paper, we mainly pay attention to the weighted sampling and reconstruction algorithm in lattice-invariant signal spaces. We give the reconstruction formula in lattice-invariant signal spaces, which is a generalization of former results in shift-invariant signal spaces. That is, we generalize and improve Aldroubi, Grochenig and Chen's results, respectively. So we obtain a general reconstruction algorithm in lattice-invariant signal spaces, which the signal spaces is sufficiently large to accommodate a large number of possible models. They are maybe useful for signal processing and communication theory. 相似文献
5.
A new optimization algorithm based on chaos 总被引：8，自引：0，他引：8
LU Hui-juan ZHANG Huo-ming MA Long-hua 《浙江大学学报(A卷英文版)》2006,7(4):539-542
INTRODUCTION Chaos (Wang et al., 2002) is a common nonlin- ear phenomenon, whose action is complex and similar to that of randomness. The characteristics of chaos being highly sensitive to the initial value of chaos make a world of differences due to the ergodic prop- erty of the phase space—chaos can go through all states in certain ranges without repetition; the inher- ent randomness of the system—means that chaos behavior is similar to randomness which is disorderly; but at the same t… 相似文献
6.
INTRODUCTIONMiningfrequentitemsetsisafundamentalandessentialprobleminmanydataminingapplica tionsincludingthediscoveryofassociationrules,strongrules,correlations,sequentialrules,epi sodes,multi dimensionalpatterns,andmanyoth erimportantdiscoverytasks (AgarwalandSri kant,1994;Wangetal.,2 0 0 2 ) .Mostalgo rithmsproposedsofarworkwellondatasetswherethesizesofitemsetsarerelativelysmall.Howev er,theyusuallycrashwithdensedatasetswheretheitemsetsizesarelarge.Suchdatasetsincludethosecomposedofque… 相似文献
7.
INTRODUCTION Clustering groups dataset data into meaning-ful subclasses in such a way that minimizes theintra-differences and maximizes the in-ter-differences of these subclasses; and is one ofthe most widely studied problems in data mining.There are many application areas for clusteringtechniques, such as statistical data analysis, patternrecognition, image processing, and other businessprocesses etc. Many clustering algorithms havebeen proposed, in part… 相似文献
8.
WANG Yuan-jun CAO Yuan 《浙江大学学报(A卷英文版)》2006,7(9):1572-1577
INTRODUCTION In Computer Aided Design, fairness is one of the basic requirements for designing curves. If the curves are not fair, the design will be unsatisfactory and the producing process will be discommodious. In practice, there are all kinds of errors such as modelling error and measuring error. It means that the information on the data points may not be accurate. In order to obtain fair curves by interpolating these data points, we should fair the data points first. This is the so… 相似文献
9.
INTRODUCTION Electrical capacitance tomography (ECT) is based on measuring the variation in capacitance be- tween pairs of electrodes surrounding a subject, and reconstructing the distribution of dielectric properties in the sensing area using the measured data. For im- age reconstruction with ECT, the linear back-pro- jection (LBP) algorithm is the most popular (Xie et al., 1992). However, it can only produce qualitative im- ages. In many cases, it is necessary to provide quantitativ… 相似文献
10.
INTRODUCTIONPeoplearebecomingmoreinterestednotonlyintextinformationbutalsoinmultimediainfor mationsuchasimage,audioandvideo .Nowmoreandmoreattentionisbeingpaidtocontent basedretrievalsystemsforwebusebecausetheyplayakeyroleinutilizinginformationavailableon… 相似文献
11.
基于点到角的最小距离提出一种判别点与多边形位置关系的新算法。通过扫描与点距离最小的线段,在多边形中有两个角共有此线段,选择其中任意一个角,定义点到此角的距离取得最小。判断点与角的内外侧关系,确定点与多边形内外侧位置关系。该算法通过点与点的距离运算避免了传统的交点、叉积的求解。比较试验表明,此新算法易于实现、计算速度快。 相似文献
12.
INTRODUCTION 2D irregular-shaped nesting problem is the problem of finding an efficient arrangement for pieces in a containing region without overlapping (Fig.1), and is aimed at maximizing use of material. Nesting problem is of great interest to garment, paper, ship building, and sheet metal industries since small improvement of layout can lead to large savings in material. Many effective solutions have been pro- posed for the case when pieces and containing region are both rectangular. … 相似文献
13.
A new calibration algorithm for multi-camera systems using 1D calibration objects is proposed. The algorithm integrates the rank-4 factorization with Zhang （2004）＇s method. The intrinsic parameters as well as the extrinsic parameters are recovered by capturing with cameras the 1D object＇s rotations around a fixed point. The algorithm is based on factorization of the scaled measurement matrix, the projective depth of which is estimated in an analytical equation instead ofa recursive form. For more than three points on a 1D object, the approach of our algorithm is to extend the scaled measurement matrix. The obtained parameters are finally refined through the maximum likelihood inference. Simulations and experiments with real images verify that the proposed technique achieves a good trade-off between the intrinsic and extrinsic camera parameters. 相似文献
14.
INTRODUCTION Most packing problems (Dowsland and Dow-sland, 1992) are NP-hard (Garey and Johnson, 1979); among which are bin-packing, floorplan, rectangle packing, packing a set of circles into a large circle or square, non-rectangular packing problems and so on (Li and Milenkovic, 1995; Liang et al., 2002; Lip-nitskii, 2002; Milenkovic and Daniels, 1996; Milenk-ovic et al., 1991; Osogami and Okano, 2003; Wang, 2002). Some of these such as bin-packing problem and rectangle packing p… 相似文献
15.
LIU Guang-hui CHEN Chuan-bo 《浙江大学学报(A卷英文版)》2007,8(8):1210-1217
When the edges of a convex polygon are traversed along one direction,the interior of the convex polygon is always on the same side of the edges. Based on this characteristic of convex polygons,a new algorithm for computing the convex hull of a simple polygon is proposed in this paper,which is then extended to a new algorithm for computing the convex hull of a planar point set. First,the extreme points of the planar point set are found,and the subsets of point candidate for vertex of the convex hull between extreme points are obtained. Then,the ordered convex hull point sequences between extreme points are constructed separately and concatenated by removing redundant extreme points to get the convex hull. The time complexity of the new planar convex hull algorithm is O(nlogh) ,which is equal to the time complexity of the best output-sensitive planar convex hull algorithms. Compared with the algorithm having the same complexity,the new algorithm is much faster. 相似文献
16.
INTRODUCTION Frequency estimation is the basis of other pa- rameter measurements of signals in intelligent in- struments and meters. Frequency estimation of sinu- soidal or nonsinusoidal signals is easier to realize under non-noisy conditions than under noisy condi- tions. Under noisy conditions, the frequency estima- tion becomes more difficult work due to distortion in sample data. Some pioneering algorithms, such as zero crossing technique (Moore et al., 1996; Begovic et al., 1993), l… 相似文献
17.
Wavelength and bandwidth allocation is important for multicast communication in optical networks. In this paper, a new method based on scheduling theory is proposed. The proposed method formulates wavelength bandwidth capacity as a large rectangle and these multicast stream bandwidth requirements as small rectangles. It treats the wavelength and bandwidth allocation question as a rectangle packing problem. The proposed algorithm solves the problem by taking quasi-human strategy with Euclidian distance. It is an effective heuristic algorithm to quickly solve multicast stream bandwidth allocation problem in optical networks by theoretic analysis. Further simulation experiments show the bandwidth allocation algorithm can increase network utilization and have a good fairness performance for unicast stream and multicast stream in optical networks. The results indicate the effectiveness of the algorithm. 相似文献
18.
提出了一种求解0-1背包问题的遗传算法,该算法首先设计出基于适应度的自适应变异策略,提高了变异的科学性和新算法的搜索能力;然后提出了基于单位价值信息和满足约束最大化的双优化策略,提高了求解的质量.3个0-1背包问题的仿真实验表明:与已有的HGA算法和GGA算法相比,新算法在求解质量上具有一定优势. 相似文献
19.
提出一种基于贪心随机自适应搜索过程的聚类算法.该算法先根据密度概念构造一个约束候选列表,然后从列表中随机选取k个对象作为K均值算法的k个起始中心点.试验结果表明该算法的聚类结果比k均值算法有显著改进. 相似文献
20.
针对三维矩形布局问题,提出一种基于评价函数的布局遗传算法.该算法根据布局已知条件建立定序和定位评价函数,然后通过对评价函数值的比较确定布局的定序和定位规则;最后采用遗传算法优化定序和定位规则的参数.算例测试结果表明,该算法具有良好的计算效果. 相似文献