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Variable Precision Rough Set and a Fuzzy Measure of Knowledge Based on Variable Precision Rough Set 被引量:2
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作者 菅利荣 达庆利 陈伟达 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期351-355,共5页
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 disc... 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... 展开更多
关键词 variable precision rough set fuzzy set information system fuzzy measures
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A Method of Gene-Function Annotation Based on Variable Precision Rough Sets 被引量:5
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作者 Zhi-li Pei Xiao-hu Shi +4 位作者 Meng Niu Xu-ning Tang Li-sha Liu Ying Kong Yan-chun Liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第3期177-184,共8页
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 annotat... 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. 展开更多
关键词 gene function ANNOTATION variable precision rough set GO BLAST
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Variable precision rough set for multiple decision attribute analysis
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作者 Lai Kin Keung 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期1-6,共6页
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 confide... 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. 展开更多
关键词 variable precision rough set multiple attributes decision making multiple decision attributes β-reduct confidence measure
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A transformation algorithm for incompatible information systems based on variable precision values
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作者 JiuyingDENG Qinruo WANG +1 位作者 Qiang CHEN Baoyu YE 《控制理论与应用(英文版)》 EI 2012年第1期113-117,共5页
The variable precision rough set (VPRS) model extends the basic rough set (RS) theory with finite uni- verses and finite evaluative measures. VPRS is concerned with the equivalence and the contained relationship b... The variable precision rough set (VPRS) model extends the basic rough set (RS) theory with finite uni- verses and finite evaluative measures. VPRS is concerned with the equivalence and the contained relationship between two sets. In incompatible information systems, the inclusion degree and/3 upper (lower) approximation of the inconsistent equivalence class to the decision equivalence classes may be affected by the variable precision. The analysis of an example of incompatible decision table shows that there is a critical point in fl available-values region. In the new/3 range limited at the critical point, the incompatible decision table can be converted to the coordination decision table reliably. The method and its algorithm implement are introduced for the critical value search. The examples of the inconsistent equivalence class transformation are exhibited. The results illustrate that this algorithm is rational and precise. 展开更多
关键词 Inconsistent equivalence class Inclusion degree Incompatible decision table variable precision
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Product Approximation of Grade and Precision 被引量:6
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作者 张贤勇 莫智文 《Journal of Electronic Science and Technology of China》 CAS 2005年第3期276-279,283,共5页
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 fo... 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. 展开更多
关键词 rough sets approximation operators operators of approximations graded rough sets variable precision rough sets
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Evaluation of Variable Rate Technology for Fertilizer Application in Permanent Pastures
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作者 J. M. Serrano J. M. Peca Shahidian 《Journal of Agricultural Science and Technology(A)》 2011年第4X期489-499,共11页
This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a signifi... This paper describes the field tests carried out to evaluate the new Vicon RS-EDW centrifugal fertilizer spreader, to be used in Precision Agriculture. The results of initial dynamic calibration tests showed a significant and systematic difference between the application rates of the two discs (about 20%). This difference had to be corrected by the manufacturer that carried out the necessary changes to the electric actuators. The fertilizer spreader had good distribution homogeneity, considering different working velocities and different positions in the parcel. The pattern distribution curve for 18% super phosphate fertilizer led to an effective working width of 28 meters, with a coefficient of variation of 15%. The longitudinal test, under experimental working conditions led to a machine delay time of 6-7 seconds. The results show an actual fertilization application density between 74%-90% of that determined for each location. These results confirm that the spreader can be used to spread fertilizer differentially in the field. 展开更多
关键词 Calibration centrifugal fertilizer spreader evaluation precision agriculture variable rate technology.
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MAINTENANCE LEVEL DECISION OF AERO-ENGINE BASED ON VPRS THEORY 被引量:3
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作者 张海军 左洪福 梁剑 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期281-284,共4页
An aero-engine is a typically repairable and complex system and its maintenance level has a close relationship with the maintenance cost. The inaccurate measurement for the maintenance level of an aero-engine can indu... An aero-engine is a typically repairable and complex system and its maintenance level has a close relationship with the maintenance cost. The inaccurate measurement for the maintenance level of an aero-engine can induce higher overhaul maintenance costs. Variable precision rough set (VPRS) theory is used to determine the maintenance level of an aero-engine. According to the relationship between condition information and performance parameters of aero-engine modules, decision rules are established for reflecting the real condition of an aeroengine when its maintenance level needs to be determined. Finally, the CF6 engine is used as an example to illustrate the method to be effective. 展开更多
关键词 repairable system AERO-ENGINE maintenance level variable precision rough set attribute reduction
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Application of Rough Set Theory in Fault Diagnostic Rules Acquisition 被引量:3
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作者 殷晨波 周庆敏 李永生 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期276-279,共4页
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 p... 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. 展开更多
关键词 variable precision rough set fault diagnosisrules acquisition
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Multi-Span and Multiple Relevant Time Series Prediction Based on Neighborhood Rough Set 被引量:1
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作者 Xiaoli Li Shuailing Zhou +1 位作者 Zixu An Zhenlong Du 《Computers, Materials & Continua》 SCIE EI 2021年第6期3765-3780,共16页
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 ... 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. 展开更多
关键词 Rainfall and runoff variable precision fuzzy neighborhood rough set LSTM MULTI-SPAN
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A Generalized Rough Set Modeling Method for Welding Process
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作者 黎文航 陈善本 +1 位作者 林涛 杜全营 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第3期319-322,327,共5页
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 ... 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. 展开更多
关键词 variable precision rough set MODELING welding process gas tungsten arc welding(GTAW)
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Text Classification Using Sentential Frequent Itemsets
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作者 刘石竹 胡和平 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第2期334-336,F0003,共4页
Text classification techniques mostly rely on single term analysis of the document data set, while more concepts, especially the specific ones, are usually conveyed by set of terms. To achieve more accurate text class... Text classification techniques mostly rely on single term analysis of the document data set, while more concepts, especially the specific ones, are usually conveyed by set of terms. To achieve more accurate text classifier, more informative feature including frequent co-occurring words in the same sentence and their weights are particularly important in such scenarios. In this paper, we propose a novel approach using sentential frequent itemset, a concept comes from association rule mining, for text classification, which views a sentence rather than a document as a transaction, and uses a variable precision rough set based method to evaluate each sentential frequent itemset's contribution to the classification. Experiments over the Reuters and newsgroup corpus are carried out, which validate the practicability of the proposed system. 展开更多
关键词 text classification sentential frequent itemsets variable precision rough set model
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