A Method of Gene-Function Annotation Based on Variable Precision Rough Sets

It is very important in the field of bioinformatics to apply computer to perform the function annotation for new sequenced bio-sequences. Based on GO database and BLAST program, a novel method for the function annotation of new biological sequences is presented by using the variable-precision rough set theory. The proposed method is applied to the real data in GO database to examine its effectiveness. Numerical results show that the proposed method has better precision, recall-rate and harmonic mean value compared with existing methods.

Variable Precision Rough Set and a Fuzzy Measure of Knowledge Based on Variable Precision Rough Set

Variable precision rough set (VPRS) is an extension of rough set theory (RST). By setting threshold value β , VPRS looses the strict definition of approximate boundary in RST. Confident threshold value for β is discussed and the method for deriving decision making rules from an information system is given by an example. An approach to fuzzy measures of knowledge is proposed by applying VPRS to fuzzy sets. Some properties of this measure are studied and a pair of lower and upper approximation operato...

Variable precision rough set for multiple decision attribute analysis

A variable precision rough set (VPRS) model is used to solve the multi-attribute decision analysis (MADA) problem with multiple conflicting decision attributes and multiple condition attributes. By introducing confidence measures and a β-reduct, the VPRS model can rationally solve the conflicting decision analysis problem with multiple decision attributes and multiple condition attributes. For illustration, a medical diagnosis example is utilized to show the feasibility of the VPRS model in solving the MADA problem with multiple decision attributes and multiple condition attributes. Empirical results show that the decision rule with the highest confidence measures will be used as the final decision rules in the MADA problem with multiple conflicting decision attributes and multiple condition attributes if there are some conflicts among decision rules resulting from multiple decision attributes. The confidence-measure-based VPRS model can effectively solve the conflicts of decision rules from multiple decision attributes and thus a class of MADA problem with multiple conflicting decision attributes and multiple condition attributes are solved.

变精度Rough Sets模型在数据挖掘中的应用

经典的粗糙集理论在进行分类时其类之间的分界线很严格,这样提高了知识属性对被研究对象识别分类的精度,但这种方式的容错能力很差,使得模型的实际适用性很弱.变精度粗糙集是对经典粗糙集理论的一种扩展,通过研究得出了知识的依赖程度饱和值不变约简法及信息熵不减约简法.

Rough sets:the classical and extended views

The article is a comprehensive review of two major approaches to rough set theory:the classic rough set model introduced by Pawlak and the probabilistic approaches.The classic model is presented as a staging ground to the discussion of two varieties of the probabilistic approach,i.e.of the variable precision and Bayesian rough set models.Both of these models extend the classic model to deal with stochastic interactions while preserving the basic ideas of the original rough set theory,such as set approximations,data dependencies,reducts etc.The probabilistic models are able to handle weaker data interactions than the classic model,thus extending the applicability of the rough set paradigm.The extended models are presented in considerable detail with some illustrative examples.

Product Approximation of Grade and Precision

The normal graded approximation and variable precision approximation are defined in approximate space. The relationship between graded approximation and variable precision approximation is studied, and an important formula of conversion between them is achieved The product approximation of grade and precision is defined and its basic properties are studied.

Application of Rough Set Theory in Fault Diagnostic Rules Acquisition

Rough set theory is a new mathematical tool to deal with vagneness and uncertainty. But original rough sets theory only generates deterministic rules and deals with data sets in which there is no noise. The variable precision rough set model （VPRSM） is presented to handle uncertain and noisy information. A method based on VPRSM is proposed to apply to fault diagnosis feature extraction and rules acquisition for industrial applications. An example for fault diagnosis of rotary machinery is given to show that the method is very effective.

Multi-Span and Multiple Relevant Time Series Prediction Based on Neighborhood Rough Set

Rough set theory has been widely researched for time series prediction problems such as rainfall runoff.Accurate forecasting of rainfall runoff is a long standing but still mostly signicant problem for water resource planning and management,reservoir and river regulation.Most research is focused on constructing the better model for improving prediction accuracy.In this paper,a rainfall runoff forecast model based on the variable-precision fuzzy neighborhood rough set(VPFNRS)is constructed to predict Watershed runoff value.Fuzzy neighborhood rough set dene the fuzzy decision of a sample by using the concept of fuzzy neighborhood.The fuzzy neighborhood rough set model with variable-precision can reduce the redundant attributes,and the essential equivalent data can improve the predictive capabilities of model.Meanwhile VFPFNRS can handle the numerical data,while it also deals well with the noise data.In the discussed approach,VPFNRS is used to reduce superuous attributes of the original data,the compact data are employed for predicting the rainfall runoff.The proposed method is examined utilizing data in the Luo River Basin located in Guangdong,China.The prediction accuracy is compared with that of support vector machines and long shortterm memory(LSTM).The experiments show that the method put forward achieves a higher predictive performance.

A Generalized Rough Set Modeling Method for Welding Process

Modeling is essential, significant and difficult for the quality and shaping control of arc welding process. A generalized rough set based modeling method was brought forward and a dynamic predictive model for pulsed gas tungsten arc welding (GTAW) was obtained by this modeling method. The results show that this modeling method can well acquire knowledge in welding and satisfy the real life application. In addition, the results of comparison between classic rough set model and back-propagation neural network model respectively are also satisfying.

一种属性变化局部变精度邻域粗糙集动态算法

传统的邻域粗糙集模型对混合型数据的抗噪能力和计算效率低下,基于矩阵理论建立了一种属性动态变化的局部变精度邻域粗糙集模型。在局部对角矩阵和中间矩阵的更新规律的基础上,构建了混合信息系统局部变精度邻域粗糙集下近似的动态更新机制,提出了一种新的属性变化的局部变精度邻域粗糙集动态算法。通过实验分析可知:所提出的动态算法具有较高的计算效率和良好的稳健性。

基于α相同度相似关系的rough集模型

Rough集理论是一种处理不完备信息系统的数学工具,但是Pawlak的经典rough集理论似乎是不可行的,因为它要求论域中数据间有很强的等价关系。在产生基本集(相似类)时,一般相似关系的分类误差较大,集对分析会把两个对立度不为0的个体划分在一起。汲取两者的优点,给出相同度的概念,只有满足一般相似关系并且相同度大于或等于阈值α的两个对象才能划分在一个基本集中,在此基础上建立基于α相同度相似关系的rough集模型。通过实例验证效果要比基于集对分析或者一般相似关系的模型更好。

基于变精度Rough集的对象甄选优化模型

定义了对象甄选信息系统,并根据属性值序列间的距离,给出了对象的相似关系,并利用Rough集理论讨论了对象的分类问题,最后给出了甄选的优化模型.

不完备信息系统中可变精度Rough集模型

本文分析了已有不完备信息系统中可变精度Rough集模型存在的不足,提出了其改进模型;通过引入遗传算法来解决模型中的阈值优选问题,使阈值优选自动化。仿真试验说明了改进模型的有效性和优越性。

区间集值变精度粗糙集

分别考虑粗糙集的对象和关系是区间集,建立了两种基于区间集的变精度粗糙集。一种是对象为区间集的区间集值变精度粗糙集,另一种是关系为区间集的区间集值变精度粗糙集。分别给出了它们的定义和性质。这一工作有助于进一步研究区间集和粗糙集。

改进粗糙集理论的无线传感器网络静态节点分类算法

因无线传感器网络中静态节点包含一定的不确定信息,决策级融合技术很难对数据进行有效刻画,导致网络静态节点分类效果差。提出一种基于改进粗糙集理论的无线传感器网络静态节点分类算法。采用多次采样法对测试结果加权处理,通过加权移动平均算法对邻居节点进行测试,基于节点密度的混合式算法对数据去噪处理。利用错误分类率中的变精度粗糙集构建改进的粗糙集模型,基于改进粗糙集理论提取无线传感器网络静态节点特征,通过支持向量机构建无线传感器网络静态节点分类模型对节点分类处理。仿真结果表明,所提方法的分类正确率始终高于96.852%、节点召回率在97.321%以上、F1值多于97%、能量消耗在12.52 J~90.20 J之间,证明所提算法具有良好的网络静态节点分类性能。

加权变精度直觉模糊序信息决策表的近似约简

以直觉模糊信息表为背景,利用粗糙集和模糊集,旨在筛除信息表中冗余的属性,提出获取决策规则的近似约简方法.首先,通过在直觉模糊集中引入带权重评分函数来定义加权直觉模糊序关系;进一步,为了提高模型分类的容错率,结合变精度粗糙集模型构建加权变精度直觉模糊序决策信息表;接着,在该决策表中提出上、下近似约简的判定定理和可辨识矩阵,进而生成两种求解上、下近似约简的方法;最后,通过具体案例和数值实验分析验证了该方法的有效性.

变精度模糊软粗糙集模型研究

针对不确定性问题中噪声数据有效处理,文章提出了一种变精度模糊软粗糙集模型。首先,基于模糊软关系和逆模糊软关系,提出了模糊软关系之间的合成运算,并采用构造性方法建立了模糊软粗糙集模型和变精度模糊软粗糙集模型;然后,讨论并证明了模糊软粗糙集模型和变精度模糊软粗糙集模型的数学特性和相关结论;最后,实例结果表明,变精度模糊软粗糙集模型可以减少噪声对数据的影响。

高温度及高湿度场叠加的地下铝土矿山全尾砂充填强度规律

为分析高温高湿环境下地下铝土矿全尾砂充填体强度及其变化规律,构建包括温度湿度在内的充填体强度影响指标体系,统计充填体强度及其影响指标的实测值,构建充填体强度变化规律分析的知识系统。考虑到充填体强度影响指标数值大小含有偏好信息及复杂环境导致的充填体强度带有偶然性的特点,将适用于偏好信息分析的优势关系粗糙集和适用于偶然性分析的变精度粗糙集联合,构建变精度优势关系粗糙集模型,以此分析充填体强度的变化发展趋势及与影响因素之间关系,最终生成充填体强度的概率性偏好规则,并提取出支持数高的规则作为规律。实例表明:采用变精度优势关系粗糙集分析温湿环境下的全尾砂充填体强度变化规律将其应用于矿山实际生产后,因全尾砂充填体强度而引发的安全事故减少50%以上,经济损失减少了60%以上,分析结果全面可靠。

一般关系下的变精度粗糙集模型

通过分析一般关系下基本粗糙集模型的不足,定义了一般关系下的多数包含关系,借助引入的 误差参数α(0≤α<1/2),给出了一般关系下的变精度粗糙集模型．在该模型中,当α=0时,退化为一般关 系下的基本粗糙集模型(Z．Pawlak模型);当|Rs(x)|·α=k时(|Rs(x)|表示元素x后继邻域Rs(x)之基 数,k为非负整数),退化为常见的程度粗糙集模型．通过它与一般关系下基本粗糙集模型(Z．Pawlak模 型)的比较,可以看出,在引入误差参数α后,能够使尽可能多的有用信息被提取、挖掘．从而克服了基 本粗糙集模型中由于要求绝对精确的包含关系而使大量有用信息丢失的现象,并讨论了所给模型的一 些性质．最后,在所给模型基础上讨论了一种广义近似空间中集合的相对可辨性、近似依赖和属性约 简．

基于邻域粒化和粗糙逼近的数值属性约简

对于空间中的任一子集,通过基本邻域信息粒子进行逼近,由此提出了邻域信息系统和邻域决策表模型.分析了该模型的性质,并且基于此模型构造了数值型属性的选择算法.利用UCI标准数据集与现有算法进行了比较分析,实验结果表明,该模型可以选择较少的特征而保持或改善分类能力.