多数据库中例外模式挖掘方法研究*

首先比较了现有的两种挖掘方法,提出了一种改进技术.综合考虑例外的局部和全局兴趣度,剔除非真正有趣的局部例外;增加两种客观度量并按模式重要度排序.实验表明该方法不仅可以有效挖掘多数据库中例外模式,而且还大大减少了用户负担.     

富硒沼泽红假单胞菌G3 菌与牛初乳复配改善小鼠免疫功能的作用研究

目的：探讨富硒沼泽红假单胞菌G3 菌(简称富硒G3 菌)与牛初乳复配对小鼠免疫功能的影响。方法：将富G3 菌与牛初乳复配形成富硒牛初乳,用环磷酰胺构建小鼠免疫低下模型,对免疫低下小鼠灌胃富硒G3 菌、牛初乳和富硒牛初乳,50d 后测定各组小鼠脏器指数、白细胞数、T 淋巴细胞阳性率、血清SOD 酶活性、全血GSH-Px活性,同时计算平均每日进食饲料质量与体质量增加量的比值。结果：富硒G3 菌、牛初乳、富硒牛初乳均能提高免疫低下小鼠对饲料的利用率,能提高免疫低下小鼠SOD、GSH-Px 活性、白细胞数和T 淋巴细胞阳性率,其中富硒牛初乳高剂量组效果最为明显,说明富硒牛初乳高剂量组能显著增强小鼠的免疫功能。     

一种恶意软件传播的离散概率模型

 复杂网络理论为恶意软件传播的研究提供了新的思路和方法。本文针对恶意软件的实际传播机制,提出一种新的离散概率DP-SI模型, 该模型可适用于任意网络拓扑。同时提出了一种节点信息网络模型方法,为大规模复杂网络及复杂网络上的传播动力学的仿真,以及离散传播动力学模型的建立,提供了有效的研究平台。仿真结果表明本模型比传统模型更接近现实,对恶意软件的控制具有一定指导意义。     

基于四元数小波幅值相位表示及分块投票策略的人脸识别方法*

提出一种基于四元数小波幅值相位表示及分块投票策略的人脸识别方法。该方法首先对人脸图像进行预处理,利用四元数小波变换的四路小波提取多个角度方向的小波系数,并求取四元数幅值和三个相位,将这些幅值和相位特征组合并分成若干子块,对每个子块根据最近邻原则进行分类,对各子块分类结果进行投票以实现人脸图像最终识别。对五个人脸数据库的实验表明,该方法具有较高识别率和对表情及光照变化的鲁棒性。     

Analysis and optimization of weighted voting systems consisting of voting units with limited availability

The voting system studied consists of n voting units each either providing a binary decision (0 or 1) or abstaining from voting. The system output is 1 if the cumulative weight of all 1-opting units is at least a pre-specified fraction τ of the cumulative weight of all non-abstaining units. Otherwise, the system output is 0.In this paper, we study the effect of limited availability of the voting units on the entire voting system reliability. Two different types of systems are considered. In the system of type 1, the absence of unit output (unit unavailability) is interpreted by the system as abstention from voting. In the system of type 2, the unavailable state of the voting unit and its abstention from voting can be distinguished and the system parameters can be adjusted to optimize its performance for each combination of available units.There are two ways to improve reliability of weighted voting system consisting of units with the given output probability distribution: optimization of system parameters (weights of units and threshold factor value) and units availability enhancement (for example, by choosing proper maintenance policy). This paper shows a method of incorporating information about units' availability into a procedure for determining the optimal system parameters. It also presents a method for determining indices that measure importance of voting units availability for both types of systems. These indices indicate voting units for which efforts of availability enhancement are the most beneficial from the entire system reliability improvement point of view.The approach is based on using a universal generating function technique and optimization procedure presented in [5]. Examples are presented.     

Feature detection of triangular meshes based on tensor voting theory

This paper presents n-dimensional feature recognition of triangular meshes that can handle both geometric properties and additional attributes such as color information of a physical object. Our method is based on a tensor voting technique for classifying features and integrates a clustering and region growing methodology for segmenting a mesh into sub-patches. We classify a feature into a corner, a sharp edge and a face. Then, finally we detect features via region merging and cleaning processes. Our feature detection shows good performance with efficiency for various dimensional models.     

Effective solution for unhandled exception in decision tree induction algorithms

This paper deals with some improvements to rule induction algorithms in order to resolve the tie that appear in special cases during the rule generation procedure for specific training data sets. These improvements are demonstrated by experimental results on various data sets. The tie occurs in decision tree induction algorithm when the class prediction at a leaf node cannot be determined by majority voting. When there is a conflict in the leaf node, we need to find the source and the solution to the problem. In this paper, we propose to calculate the Influence factor for each attribute and an update procedure to the decision tree has been suggested to deal with the problem and provide subsequent rectification steps.     

余度系统中的动态同步和表决控制

在多通道余度系统的研究和应用中,同步问题是整个余度系统正确运行的基本保证。基于多交叉通道模型和同步时间的静态分配策略,提出动态时间容错方法。针对该方法,设计基于时间容错的动态表决控制算法,实现多通道系统中的动态同步。给出动态同步表决控制逻辑,用于控制表决时间并监测表决数据。理论分析和实验结果表明,时间容错的动态表决控制算法扩展了任务处理的时间窗口,与静态同步算法相比,可有效降低通道故障率,提高对瞬时干扰的抵御能力以及余度系统的可靠性。