Mining association rules in incomplete information systems

Based on the rough set theory which is a powerful tool in dealing with vagueness and uncertainty, an algorithm to mine association rules in incomplete information systems was presented and the support and confidence were redefined. The algorithm can mine the association rules with decision attributes directly without processing missing values. Using the incomplete dataset Mushroom from UCI machine learning repository, the new algorithm was compared with the classical association rules mining algorithm based on Apriori from the number of rules extracted, testing accuracy and. execution time. The experiment results show that the new algorithm has advantages of short execution time and high accuracy.     

Mining multilevel spatial association rules with cloud models

The traditional generalization-based knowledge discovery method is introduced. A new kind of muhilevel spatial association of the rules mining method based on the cloud model is presented. The cloud model integrates the vague and random use of linguistic terms in a unified way. With these models, spatial and nonspatial attribute values are well generalized at multiple levels, allowing discovery of strong spatial association rules.Combining the cloud model based method with Apriori algorithms for mining association rules from a spatial database shows benefits in being effective and flexible.     

Adaptive key SURF feature extraction and application in unmanned vehicle dynamic object recognition

A new method based on adaptive Hessian matrix threshold of finding key SRUF( speeded up robust features) features is proposed and is applied to an unmanned vehicle for its dynamic object recognition and guided navigation. First,the object recognition algorithm based on SURF feature matching for unmanned vehicle guided navigation is introduced. Then,the standard local invariant feature extraction algorithm SRUF is analyzed,the Hessian Metrix is especially discussed,and a method of adaptive Hessian threshold is proposed which is based on correct matching point pairs threshold feedback under a close loop frame. At last,different dynamic object recognition experiments under different weather light conditions are discussed. The experimental result shows that the key SURF feature abstract algorithm and the dynamic object recognition method can be used for unmanned vehicle systems.     

A self region based real-valued negative selection algorithm

Point-wise negative selection algorithms, which generate their detector sets based on point of self data, have lower training efficiency and detection rate. To solve this problem, a self region based real-valued negative selection algorithm is presented. In this new approach, the continuous self region is defined by the collection of self data, the partial training takes place at the training stage according to both the radius of self region and the cosine distance between gravity of the self region and detector candidate, and variable detectors in the self region are deployed. The algorithm is tested using the triangle shape of self region in the 2-D complement space and KDD CUP 1999 data set. Results show that, more information can be provided when the training self points are used together as a whole, and compared with the point-wise negative selection algorithm, the new approach can improve the training efficiency of system and the detection rate significantly.     

Automated pattern-directed refactoring for complex conditional statements

Complex conditional statement is one of the bad code smells, which affects the quality of the code and design of software. In the proposed approach, two commonly-used design patterns for handling complex conditional statements are selected, and they are the factory method pattern and the strategy pattem. Two pattern-directed refactoring approaches based on the two design patterns are proposed. Each approach contains a refactoring opportunities identification algorithm and an automated refactoring algorithm. After parsing the abstract syntax tree generated from source code, the refactoring opportunities are identified effectively and automatically. Then, for candidate code, refactoring algorithms are executed automatically, which are used to simplify or remove complex conditional statements. By empirical analysis and quality assessment, the code after refactoring has better maintainability and extensibility, and the proposed approach for automated pattern-directed refactoring succeeds to reduce code size and complexity of classes.     

Efficient Activation Method of Hardware Trojan Based on Greedy Algorithm

To generate test vector sets that can efficiently activate hardware Trojans and improve probability of the hardware Trojan activation,an efficient hardware Trojan activation method is proposed based on greedy algorithm for combinatorial hardware Trojans.Based on the greedy algorithm and the recursive construction method in the combination test,the method formulates appropriate and useful greedy strategy and generates test vector sets with different combinatorial correlation coefficients to activate hardware Trojans in target circuits.The experiment was carried out based on advanced encryption standard (AES) hardware encryption circuit,different combinatorial hardware Trojans were implanted in AES as target circuits,the experiment of detecting hardware Trojans in target circuits was performed by applying the proposed method and different combinatorial hardware Trojans in target circuits were activated successfully many times in the experiment.The experimental results show that the test vector sets generated using the proposed method could effectively activate combinatorial hardware Trojans,improve the probability of the hardware Trojan being activated,and also be applied to practice.     

Continuous and smooth gait transition in a quadruped robot based on CPG

To improve the smoothness of motion control in a quadruped robot, a continuous and smooth gait transition method based on central pattern generator (CPG) was presented to solve the unsmooth or failed problem which may result in phase-locked or sharp point with direct replacement of the gait matrix. Through improving conventional weight matrix, a CPG network and a MATLAB/Simulink model were constructed based on the Hopf oscillator for gait generation and transition in the quadruped robot. A co-simulation was performed using ADAMS/MATLAB for the gait transition between walk and trot to verify the correctness and effectiveness of the proposed CPG gait generation and transition algorithms. Related methods and conclusions can technically support the motion control technology of the quadruped robot.     

Multi-channel fast super-resolution image reconstruction based on matrix observation model

A multi-channel fast super-resolution image reconstruction algorithm based on matrix observation model is proposed in the paper,which consists of three steps to avoid the computational complexity: a single image SR reconstruction step,a registration step and a wavelet-based image fusion. This algorithm decomposes two large matrixes to the tensor product of two little matrixes and uses the natural isomorphism between matrix space and vector space to transform cost function based on matrix-vector products model to matrix form. Furthermore,we prove that the regularization part can be transformed to the matrix formed. The conjugate-gradient method is used to solve this new model. Finally,the wavelet fusion is used to integrate all the registered highresolution images obtained from the single image SR reconstruction step. The proposed algorithm reduces the storage requirement and the calculating complexity,and can be applied to large-dimension low-resolution images.     

Adaptive Neighboring Selection Algorithm Based on Curvature Prediction in Manifold Learning

Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear, global and local algorithms are proposed. The key step of manifold learning algorithm is the neighboring region selection. However, so far for the references we know, few of which propose a generally accepted algorithm to well select the neighboring region. So in this paper, we propose an adaptive neighboring selection algorithm, which successfully applies the LLE and ISOMAP algorithms in the test. It is an algorithm that can find the optimal K nearest neighbors of the data points on the manifold. And the theoretical basis of the algorithm is the approximated curvature of the data point on the manifold. Based on Riemann Geometry, Jacob matrix is a proper mathematical concept to predict the approximated curvature. By verifying the proposed algorithm on embedding Swiss roll from R3 to R2 based on LLE and ISOMAP algorithm, the simulation results show that the proposed adaptive neighboring selection algorithm is feasible and able to find the optimal value of K, making the residual variance relatively small and better visualization of the results. By quantitative analysis, the embedding quality measured by residual variance is increased 45.45％ after using the proposed algorithm in LLE.     

Improved Ant Colony Algorithm for Vehicle Scheduling Problem in Airport Ground Service Support

Support vehicles are part of the main body of airport ground operations, and their scheduling efficiency directly impacts flight delays. A mathematical model is constructed and the responsiveness of support vehicles for current operational demands is proposed to study optimization algorithms for vehicle scheduling. The model is based on the constraint relationship of the initial operation time, time window, and gate position distribution, which gives an improvement to the ant colony algorithm(AC...     

一种多重最小支持度关联规则挖掘算法

针对单一最小支持度挖掘关联规则不能反应不同数据项出现频度与性质的问题,提出了一个基于频繁模式树的多重支持度关联规则挖掘算法MSDMFIA(Multiple minimum Supports for Discover Maximum Fre-quent Item sets Algorithm),根据不同数据项的特点定义多重支持度,通过挖掘数据库中的最大频繁项目集,计算最大频繁候选项目集在数据库中的支持度来发现关联规则.该算法可以解决关联规则挖掘中经常出现的稀少数据项问题,并解决了传统的关联规则挖掘算法中的生成频繁候选集和多次扫描数据库的性能瓶颈.实验结果表明,本文提出的算法在功能和性能方面均优于已有算法.     

一个改进项目的加权关联规则挖掘算法

提出了一个改进的项目加权关联规则挖掘算法.该算法利用一个加权频繁项目集必须满足的加权支持度下界,对加权频繁候选项目集进行剪枝,该下界计算简便,可以减少挖掘的计算量.理论分析和实验表明本算法和MINWAL(W)相比,具有生成候选集数量少、挖掘效率高等特点,特别在项目权值相差不大时,本算法的优势更明显.     

TRISCAN-IA:一种间接关联挖掘的快速算法

间接关联是数据挖掘领域中一种数据项之间的关联关系,为了有效地应用于市场营销、智能数据分析、web日志分析等领域,给出了一个基于频繁项目对支持矩阵直接生成频繁项目对之间候选间接关联的挖掘算法(TRISCAN-IA)。该算法只需要3次扫描数据集即可找出所有的间接关联,从而提高了算法的运行效率、在一个web log的真实数据集上进行了试验,与现有算法的比较表明,该算法具有更好的性能。     

基于FP-Tree的敏感性关联规则隐藏的研究

敏感性关联规则的隐藏是最大程度地保持原始数据集的其他特征,保证敏感规则不被挖掘出来.针对已有的基于对原始数据集中事务修改的方法产生大量I/O操作的问题,提出了基于频繁模式树(FP-tree)的敏感性关联规则隐藏的方法.该方法首先利用FP-tree存储了与事务数据库相关的全部信息,减少了产生和测试候选集耗费的大量时间;再利用改进的频繁模式树(IFP-tree)是单向的,快速挖掘出最大频繁项目集,确定敏感性关联规则;然后删除敏感关联规则对应的频繁项目集,更新IFP-tree项目集节点和相应的项目头表的计数,对更新的IFP-tree反向挖掘生成新的不包含敏感关联规则的事务数据库.实例和理论分析表明,该方法是正确和高效的.     

一种基于MapReduce的Apriori改进算法研究

提出了一种基于MapReduce模型,利用向量矩阵和Apriori算法实现关联规则数据挖掘的新算法.算法利用MapReduce模型处理向量矩阵,结合Apriori算法思想,产生局部频繁项集,通过合并处理得到全局频繁项集.实验证明算法能提高关联规则挖掘的效率.     

关联规则挖掘中Apriori算法的研究与改进

对Apriori算法加以改进,提出了一种更高效的关联规则挖掘算法,在扫描数据库的同时把支持每个项目的事务都标记出来,采用一种新的方法来计算候选项目集的支持度．该算法只需对源数据库进行一次扫描,就可以找出所有的频繁集,具有很高的效率．     

基于FP树的最大频繁项目集增量式更新算法

发现最大频繁项目集是关联规则挖掘的重要步骤,针对关联规则挖掘中最小支持度发生变化的增量式更新问题,提出了高效发现最大频繁项目集的更新算法.该算法在FP树的基础上增加了记录各项目支持数的表,在头表中增加了域,从而减少了访问事务数据库和FP树的时间,提高了发现最大频繁项目集的效率.     

基于FP树的最大频繁项目集增量式更新算法

发现最大频繁项目集是关联规则挖掘的重要步骤，针对关联规则挖掘中最小支持度发生变化的增量式更新问题，提出了高效发现最大频繁项目集的更新算法．该算法在FP树的基础上增加了记录各项目支持数的表，在头表中增加了域，从而减少了访问事务数据库和FP树的时间，提高了发现最大频繁项目集的效率．     

基于模式分解树的增量挖掘

数据挖掘具有广泛的应用,频繁模式发现是关联规则挖掘问题的重要组成部分。频繁模式的增量挖掘是一个挑战性的任务,已有的几种基于Apriori思想的方法,具有代价太高的弱点。本文提出了一个基于模式分解树,不需要扫描原数据库的增量挖掘算法。通过合理地组织候选项索引,可以取得较高的效率。     

挖掘关联规则Apriori算法的一种改进

本研究在对Apriori算法分析的基础上,提出了改进的Apriori算法。改进后的算法采用矩阵表示数据库,减少了扫描事物数据库的次数;利用向量运算来实现频繁项集的计数,同时及时地去掉不必要的数据,减少了数据运算,从而提高了算法的运行效率。