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Entropy weight coefficient model and its application in evaluation of groundwater vulnerability of the Sanjiang Plain 被引量:4
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作者 LIU Rentao FU Qiang GAI Zhaomei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第4期368-373,共6页
The research of groundwater vulnerability is the basic work to protect the groundwater. For utilizing groundwater resource continuably, groundwater vulnerability evaluation is necessary. Useful reference to protect, e... The research of groundwater vulnerability is the basic work to protect the groundwater. For utilizing groundwater resource continuably, groundwater vulnerability evaluation is necessary. Useful reference to protect, exploit and utilize on groundwater resource are provided rationally. According to the real condition of Sanjiang Plain, the indexes system is established based on the traditional DRASTIC model. The new system includes the following seven indexes: Depth of Water, Net Recharge, Aquifer Media, Soil Media, Conductivity of the Aquifer, Land Utilizing Ratio and Populace Density. The related analysis appears that the system is rather reasonable. Because traditional methods, such as analytic hierarchy process and fuzzy mathematics theory, can't be avoided human interference in selection of weights, they could lead to an imprecise result. In order to evaluate the groundwater vulnerability reasonably, entropy weight coefficient method is applied for the first time, which provides a new way to groundwater vulnerability evaluation. The method is a model whose weights are insured by the calculation process, so the artificial disturb can be avoided. It has been used to evaluate the groundwater vulnerability in Sanjiang Plain. The satisfied result is acquired. Comparably, the same result is acquired by the other method named projection pursuit evaluation based on real-coded accelerating genetic algorithm. It shows that entropy weight coefficient method is applicable on groundwater vulnerability evaluation. The evaluation result can provide reference on the decision-making departments. 展开更多
关键词 groundwater vulnerability entropy weight coefficient model indexes system EVALUATION
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Study on Entropy Weight Coefficient Method and Application for Water Quality Evaluation
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作者 MENBao-hui FUQiang ZHAOXie-jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期66-68,共3页
In order to evaluate the quality of water environment, the conception of entropy is applied in information science, and the entropy weight model is built to evaluate comprehensively water quality. The indexes weights ... In order to evaluate the quality of water environment, the conception of entropy is applied in information science, and the entropy weight model is built to evaluate comprehensively water quality. The indexes weights of water quality are determined by value of entropy. This kind of method is applied on evaluating water quality in the new water to be built. The result shows that the water quality in it which supply water is between grade Ⅲ and Ⅳ, and the result is similar to that of gray related method. 展开更多
关键词 entropy weight coefficient method water quality gray related method
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Study on Eco-environmental Stress Based on the Method of Entropy-GM(1,1) ——A Case Study in Tongyu County of Jilin Province
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作者 Wang Xuege Si Ai +2 位作者 Wei Chunfeng Lv Jun Wang Yanmei 《Meteorological and Environmental Research》 CAS 2015年第3期8-12,共5页
This paper takes the Tongyu County as an example, based on the evaluation indicator system of eco-environmental stress, using the method of the entropy- GM(1,1 ), the eco-environmental stress is evaluated and foreca... This paper takes the Tongyu County as an example, based on the evaluation indicator system of eco-environmental stress, using the method of the entropy- GM(1,1 ), the eco-environmental stress is evaluated and forecasted, Results show that the shortage of water resources, the desertification, the salinization, the grassland degeneration and the population increase are major stress factors of eco-environment worsening in the Tongyu County; eco-environmental stress coefficient from 1994 to 2013 in the region was increasing year by year, and the stress degree jumped from level-Ⅲ to level-Ⅳ. The forecast results show that if the measures don't be taken to protect eco-environment, the stress coefficient still grows, and the stress degree aggravates. In view of the above situation, we take the measures to lighten eco-environment stress, and promote the coordi- nated development of resources, environment and social economy, which is linking rivers and lakes, water resources optimization, preventing and controlling the desertification and the salinization, improving the degenerated grassland. 展开更多
关键词 Eco-environmental stress Stress coefficient. entropy - GM 1:1) Songnen Plain Tongyu County China
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Detection of healthy and pathological heartbeat dynamics in ECG signals using multivariate recurrence networks with multiple scale factors
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作者 马璐 陈梅辉 +2 位作者 何爱军 程德强 杨小冬 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期273-282,共10页
The electrocardiogram(ECG)is one of the physiological signals applied in medical clinics to determine health status.The physiological complexity of the cardiac system is related to age,disease,etc.For the investigatio... The electrocardiogram(ECG)is one of the physiological signals applied in medical clinics to determine health status.The physiological complexity of the cardiac system is related to age,disease,etc.For the investigation of the effects of age and cardiovascular disease on the cardiac system,we then construct multivariate recurrence networks with multiple scale factors from multivariate time series.We propose a new concept of cross-clustering coefficient entropy to construct a weighted network,and calculate the average weighted path length and the graph energy of the weighted network to quantitatively probe the topological properties.The obtained results suggest that these two network measures show distinct changes between different subjects.This is because,with aging or cardiovascular disease,a reduction in the conductivity or structural changes in the myocardium of the heart contributes to a reduction in the complexity of the cardiac system.Consequently,the complexity of the cardiac system is reduced.After that,the support vector machine(SVM)classifier is adopted to evaluate the performance of the proposed approach.Accuracy of 94.1%and 95.58%between healthy and myocardial infarction is achieved on two datasets.Therefore,this method can be adopted for the development of a noninvasive and low-cost clinical prognostic system to identify heart-related diseases and detect hidden state changes in the cardiac system. 展开更多
关键词 electrocardiogram signals multivariate recurrence networks cross-clustering coefficient entropy multiscale analysis
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Quantitative Diagnosis of Fault Severity Trend of Rolling Element Bearings 被引量:6
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作者 CUI Lingli MA Chunqing +1 位作者 ZHANG Feibin WANG Huaqing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第6期1254-1260,共7页
The condition monitoring and fault diagnosis of rolling element bearings are particularly crucial in rotating mechanical applications in industry. A bearing fault signal contains information not only about fault condi... The condition monitoring and fault diagnosis of rolling element bearings are particularly crucial in rotating mechanical applications in industry. A bearing fault signal contains information not only about fault condition and fault type but also the severity of the fault. This means fault severity quantitative analysis is one of most active and valid ways to realize proper maintenance decision. Aiming at the deficiency of the research in bearing single point pitting fault quantitative diagnosis, a new back-propagation neural network method based on wavelet packet decomposition coefficient entropy is proposed. The three levels of wavelet packet coefficient entropy(WPCE) is introduced as a characteristic input vector to the BPNN. Compared with the wavelet packet decomposition energy ratio input vector, WPCE shows more sensitive in distinguishing from the different fault severity degree of the measured signal. The engineering application results show that the quantitative trend fault diagnosis is realized in the different fault degree of the single point bearing pitting fault. The breakthrough attempt from quantitative to qualitative on the pattern recognition of rolling element bearings fault diagnosis is realized. 展开更多
关键词 rolling bearing fault quantitative analysis back-propagation neural network wavelet packet coefficient entropy wavelet packet energy ratio
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