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基于神经网络的高血压在线风险评估系统   总被引:1,自引:0,他引:1  
由于先前的研究工作不够综合和精确,不足于建立准确的高血压风险评估系统,根据2231个正常样本及823个高血压样本计算的信息增益,对高血压致病因素的重要程度进行了排序,总共建立和测试了42个不同的神经网络模型,发现了一个输入为26个致病因素的神经网络模型,其预测精度远高于先前研究取得的81.61%,该模型关于“是否高血压”、“收缩压”、“舒张压”的预测符合率分别为95.79%,98.22%和98.41%.基于发现的神经网络模型及面向对象的技术,开发了一个能自动收集新样本、学习新样本并能改进预测精度的高血压风险在线评估系统.  相似文献   
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Mean decision power (MDP) is an important criterion of a new reduction model, and relative decision power (RDP) and amount of rules (AR) are key parameters of MDP. This paper presents two important properties: relationship between RDP and AR, and relationship between MDP rule set of parent decision table and MDP rule set of child decision table. These properties can help better understanding of the new reduction model and are useful tools by which one can rapidly derive an MDP rule set.  相似文献   
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为了解决频繁树模式挖掘中频繁子树的数目通常太大的问题,提出了频繁子树精简基的概念,精简基由相对于一系列支持度阈值的最大频繁子树组成,它是频繁子树的一个子集,可用来估计任一频繁子树的支持度,并能将误差控制在确定范围内.提出了一个在带标号的有根的有序树的数据库中挖掘这种子树精简基的算法,该算法采用最右扩展方法系统地生成所有的频繁有序有根子树.采用的剪枝技术能尽早地剪掉一些不可能生成最大频繁子树的分枝,还采用了启发式的技术来安排计算的次序以尽可能避免代价高的计算.实验结果表明该精简基的大小不到全集的10%,算法的性能也比挖掘全集的算法要高.  相似文献   
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The attribute reduction algorithms of decision table based on discernible matrix are required to construct discernible matrix, which reduces efficiency of algorithms. In this paper, the relationship between attribute discernible matrix and its discernibility is first established for general information systems. Based on the idea that the equivalent discernible matrix has a same attribute reduction, existing matrices are modified and a formula of attribute discernibility associated with algebraic reduction for decision table is proposed. A heuristic attribute reduction algorithm based on attribute discernibility is presented. Experimental results indicate that the algorithm can more easily explore an optimal or sub-optimal reduction, and is efficient.  相似文献   
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研究了基于样式相似性的子空间聚类问题,使用样式相似性作为相似性度量.与在所有维或者子维集上聚集距离相近的对象的传统聚类方法不同的是,样式相似性寻找的是这样一种有趣的样式:对象在子维上呈现出相同起伏的一致变化.提出了一种挖掘基于样式相似性的最大子空间聚类的方法EMaPle.一般情况下数据集属性数目远小于对象数目,因此仅在属性计数空间查找簇,然后运用一些修剪策略.该方法能够找到同时满足一致性约束、大小约束和被MaPle忽视了的符号约束的聚类.在合成和实际数据集上的实验结果表明该算法优于原来的MaPle算法.  相似文献   
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Reflective real-time component model is a special component model, which can identify timing constraint characteristics of component and support dynamic design-time amendment of real-time component according to users' requirements. The reflective real-time component runtime environment is a bearing space and reflective infrastructure for this special component model. It consists of three parts and manages the lifecycle and various relevant services of reflective real-time component. In this paper its mechanism and relevant key techniques in design and realization are formally specified with the communicating sequential processing (CSP) and the extended timed communicating sequential processing (TCSP). Finally a prototype is established. Experimental study shows that this runtime environment can introduce a relevant reflective infrastructure guaranteeing dynamic and real-time features of software component.  相似文献   
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1 Introduction Data miningis currently receiving much research at-tention. Real-life data are frequently i mperfect : Erro-neous ,incomplete , uncertain and vague .In this pa-per , we investigate data incompleteness ,i.e., miss-ing of attribute values .Fo…  相似文献   
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近年来,随着技术的发展,PLC作为传统继电接触控制装置的替代品,已广泛应用于工业控制的各个领域。由于它可通过修改软件来灵活改变控制过程,而且具有体积小,组装灵活,编程简单,抗干扰能力强,以及可靠性高,可维修性好等特点,广泛用于控制设备的技术改造。本文以烟厂制丝车间的控制秤为例,提出了一种以PLC为工作主机的动态测量控制系统,其中包括组成结构、工作原理、硬件构成及软件的设计。  相似文献   
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