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Carbon efficiency evaluation method for urban energy system with multiple energy complementary
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作者 Xianan Jiao Jiekang Wu +1 位作者 Yunshou Mao Mengxuan Yan 《Global Energy Interconnection》 EI CSCD 2024年第2期142-154,共13页
Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple compleme... Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources. 展开更多
关键词 Urban energy systems(UESs) Multiple energy complementary system Carbon efficiency evaluation Data downscaling Subjective and objective weight gray correlation analysis
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Evaluation and prediction of earth pressure balance shield performance in complex rock strata:A case study in Dalian,China 被引量:1
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作者 Xiang Shen Dajun Yuan +2 位作者 Xing-Tao Lin Xiangsheng Chen Yuansheng Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1491-1505,共15页
This research explores the potential for the evaluation and prediction of earth pressure balance shield performance based on a gray system model.The research focuses on a shield tunnel excavated for Metro Line 2 in Da... This research explores the potential for the evaluation and prediction of earth pressure balance shield performance based on a gray system model.The research focuses on a shield tunnel excavated for Metro Line 2 in Dalian,China.Due to the large error between the initial geological exploration data and real strata,the project construction is extremely difficult.In view of the current situation regarding the project,a quantitative method for evaluating the tunneling efficiency was proposed using cutterhead rotation(R),advance speed(S),total thrust(F)and torque(T).A total of 80 datasets with three input parameters and one output variable(F or T)were collected from this project,and a prediction framework based gray system model was established.Based on the prediction model,five prediction schemes were set up.Through error analysis,the optimal prediction scheme was obtained from the five schemes.The parametric investigation performed indicates that the relationships between F and the three input variables in the gray system model harmonize with the theoretical explanation.The case shows that the shield tunneling performance and efficiency are improved by the tunneling parameter prediction model based on the gray system model. 展开更多
关键词 evaluation of earth pressure balance shield PERFORMANCE gray system model Metro construction Rock strata Field data prediction
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Program evaluation and its application to equipment based on super-efficiency DEA and gray relation projection method 被引量:4
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作者 Linbing Tang Dong Guo +1 位作者 Jie Wu Qingmei Tan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1037-1042,共6页
For the gray attributes of the equipment program and its difficulty to carry out the quantitative assessment of the equipment program information, the gray relation projection method is simply reviewed. Combining the ... For the gray attributes of the equipment program and its difficulty to carry out the quantitative assessment of the equipment program information, the gray relation projection method is simply reviewed. Combining the super-data envelopment analysis(DEA) model and the gray system theory, a new super-DEA for measuring the weight is proposed, and a gray relation projection model is established to rank the equipment programs. Finally, this approach is used to evaluate the equipment program. The results are verified valid and can provide a new way for evaluating the equipment program. 展开更多
关键词 index weight discriminate coefficient gray relation projection method program evaluation
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Support vector regression-based operational effectiveness evaluation approach to reconnaissance satellite system
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作者 HAN Chi XIONG Wei +1 位作者 XIONG Minghui LIU Zhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1626-1644,共19页
As one of the most important part of weapon system of systems(WSoS),quantitative evaluation of reconnaissance satellite system(RSS)is indispensable during its construction and application.Aiming at the problem of nonl... As one of the most important part of weapon system of systems(WSoS),quantitative evaluation of reconnaissance satellite system(RSS)is indispensable during its construction and application.Aiming at the problem of nonlinear effectiveness evaluation under small sample conditions,we propose an evaluation method based on support vector regression(SVR)to effectively address the defects of traditional methods.Considering the performance of SVR is influenced by the penalty factor,kernel type,and other parameters deeply,the improved grey wolf optimizer(IGWO)is employed for parameter optimization.In the proposed IGWO algorithm,the opposition-based learning strategy is adopted to increase the probability of avoiding the local optima,the mutation operator is used to escape from premature convergence and differential convergence factors are applied to increase the rate of convergence.Numerical experiments of 14 test functions validate the applicability of IGWO algorithm dealing with global optimization.The index system and evaluation method are constructed based on the characteristics of RSS.To validate the proposed IGWO-SVR evaluation method,eight benchmark data sets and combat simulation are employed to estimate the evaluation accuracy,convergence performance and computational complexity.According to the experimental results,the proposed method outperforms several prediction based evaluation methods,verifies the superiority and effectiveness in RSS operational effectiveness evaluation. 展开更多
关键词 reconnaissance satellite system(RSS) support vector regression(SVR) gray wolf optimizer opposition-based learning parameter optimization effectiveness evaluation
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Evaluation of Farmland Drainage Water Quality by Fuzzy–Gray Combination Method 被引量:1
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作者 Xiaoling Wang Songmin Li +2 位作者 Yuling Yan Xiaotong Zheng Fuchao Zhang 《Transactions of Tianjin University》 EI CAS 2019年第1期91-100,共10页
The complex relationships between indicators and water conditions cause fuzzy and gray uncertainties in evaluation of water quality. Compared to conventional single-factor evaluation methods, the combination evaluatio... The complex relationships between indicators and water conditions cause fuzzy and gray uncertainties in evaluation of water quality. Compared to conventional single-factor evaluation methods, the combination evaluation method can consider these two uncertainties to produce more objective and reasonable evaluation results. In this paper, we propose a combination evaluation method with two main parts:(1) the use of fuzzy comprehensive evaluation and gray correlation analysis as submodels with which to consider the fuzzy and gray uncertainties and(2) the establishment of a combination model based on minimum bias squares. In addition, using this method, we evaluate the water quality of a ditch in a typical rice–wheat system of Yixing city in the Taihu Lake Basin during three rainfall events. The results show that the ditch water quality is not good and we found the chemical oxygen demand to be the key indicator that affects water quality most significantly. The proposed combination evaluation method is more accurate and practical than single-factor evaluation methods in that it considers the uncertainties of fuzziness and grayness. 展开更多
关键词 Combination evaluation of water quality FUZZY comprehensive evaluation METHOD gray correlation analysis METHOD FARMLAND DITCH Key indicator
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Neural Network Based Multi-level Fuzzy Evaluation Model for Mechanical Kinematic Scheme
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作者 BO Ruifeng,LI Ruiqin (Department of Mechanical Engineering,North University of China,Taiyuan 030051,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期301-306,共6页
To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure ... To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation. 展开更多
关键词 NEURAL network mechanical KINEMATIC SCHEME multi-level evaluation model FUZZY
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Evaluation of Development Level of New Four Modernizations Based on Gray Relational Model——A Case Study of 14 Cities in Hunan Province
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作者 Naman YANG 《Asian Agricultural Research》 2017年第12期10-16,67,共8页
The development level of industrialization,informationization,urbanization and agricultural modernization(New Four Modernizations) is an important indicator for evaluation of regional economic development.In this pape... The development level of industrialization,informationization,urbanization and agricultural modernization(New Four Modernizations) is an important indicator for evaluation of regional economic development.In this paper,an indicator system was designed for evaluation of the development level of New Four Modernizations according to the interaction mechanism between them.It introduced the data related to New Four Modernizations of 14 cities in Hunan Province during 2004 and 2012,and made a comprehensive analysis of the development level of New Four Modernizations in these cities by entropy-gray relational method.It found that the development level of New Four Modernizations in 14 cities in Hunan Province was extremely uneven,and the stronger would become stronger,while the weaker would become weaker,like Matthew effect.Thus,it is required to straighten out the development idea,carry out reform and innovation in the mechanism construction,urbanrural integration,interaction and integration,and regional coordination,to promote simultaneous development of New Four Modernizations. 展开更多
关键词 New Four Modernizations evaluation ENTROPY gray relational analysis
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Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value 被引量:7
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作者 TIAN Wen-xin, LI Zuo-yong, LIU Wei, YU Chun-xue College of Resources and Environmental Sciences, Chengdu University of Information Technology, Chengdu 610225, China 《Meteorological and Environmental Research》 CAS 2011年第4期65-67,71,共4页
[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey cl... [Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment. 展开更多
关键词 NORMALIZATION gray clustering method Eco-environment quality evaluation Chaohu basin China
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Study on Comprehensive Evaluation Method of China Coal Mine Enterprises
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作者 安景文 张兴平 杜蓉晖 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期182-184,共3页
In view of the drawbacks of the evaluation methods of fuzzy comprehension, relative correlation and weighted correlation, an improved gray comprehensive evaluation model is put forward. By use of it, the comprehensive... In view of the drawbacks of the evaluation methods of fuzzy comprehension, relative correlation and weighted correlation, an improved gray comprehensive evaluation model is put forward. By use of it, the comprehensive evaluation of 75 major state-owned coal mine is carried out. 展开更多
关键词 gray COMPREHENSIVE evaluation POSITIVE STUDY
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To Evaluate of the Self-dependent Innovation Ability of Equipment Manufacturing Enterprises in Shaanxi Province
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作者 WANG Shao-hua ZHAO Fei 《International Journal of Plant Engineering and Management》 2013年第3期186-192,共7页
For an enterprise, what is important is to have the self-dependent innovation ability so that it can en- hance the core competence unceasingly and acquire sustainable competitive advantages. In this paper, the indi- c... For an enterprise, what is important is to have the self-dependent innovation ability so that it can en- hance the core competence unceasingly and acquire sustainable competitive advantages. In this paper, the indi- cator system of the self-dependent innovation ability of equipment manufacturing enterprises in Shaanxi province is constructed, in which includes 4 one-level indicators and 13 two-level indicators; and conducts empirical re- search by applying the multi-level fuzzy comprehensive evaluation method. 展开更多
关键词 equipment manufacturing enterprises self-dependent innovation ability multi-level fuzzy evaluation
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Partner Selection Analysis and System Development Based on Gray Relation Analysis for an Agile Virtual Enterprise
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作者 CHEN Hua CAO Yan ZHAO Ru-jia 《International Journal of Plant Engineering and Management》 2005年第4期241-248,共8页
This paper analyzes the state of the art of partner selection and enumerates the advantage of partner selection based on gray relation analysis comparing to the other algorithms of the partner selection. Furthermore, ... This paper analyzes the state of the art of partner selection and enumerates the advantage of partner selection based on gray relation analysis comparing to the other algorithms of the partner selection. Furthermore, partner selection system based on gray relation for an Agile Virtual Enterprise(AVE) is analyzed and designed based on the definition and characteristics of the AVE. According to J2EE mode, the architecture of the partner selection system is put forward and the system is developed t^ing JSP, EJB and SQL Server. The paper lays emphasis on a gray relational mathematic model, AVE evaluation infrastructure, a core algorithm of partner selection and a multi-layer gray relation selection process. 展开更多
关键词 partner selection gray relation analysis agile virtual enterprise AVE) multi-layergray relation selection evaluation infrastructure
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Fuzzy pattern recognition model of geological sweetspot for coalbed methane development
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作者 LIU Gaofeng LIU Huan +3 位作者 XIAN Baoan GAO Deli WANG Xiaoming ZHANG Zhen 《Petroleum Exploration and Development》 SCIE 2023年第4期924-933,共10页
From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development a... From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development are determined, and the evaluation index system of geological sweetspot for CBM development is established. On this basis, the fuzzy pattern recognition(FPR) model of geological sweetspot for CBM development is built. The model is applied to evaluate four units of No.3 Coal Seam in the Fanzhuang Block, southern Qinshui Basin, China. The evaluation results are consistent with the actual development effect and the existing research results, which verifies the rationality and reliability of the FPR model. The research shows that the proposed FPR model of geological sweetspot for CBM development does not involve parameter weighting which leads to uncertainties in the results of the conventional models such as analytic hierarchy process and multi-level fuzzy synthesis judgment, and features a simple computation without the construction of multi-level judgment matrix. The FPR model provides reliable results to support the efficient development of CBM. 展开更多
关键词 coalbed methane development geological sweetspot evaluation index system analytic hierarchy process multi-level fuzzy synthesis judgment fuzzy pattern recognition
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Determination of amount of irrigation and nitrogen for comprehensive growth of greenhouse cucumber based on multi-level fuzzy evaluation
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作者 Zhihao He Tingting Hong +3 位作者 Zelin Cai Zhi Yang Manning Li Zhi Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第2期35-42,共8页
In the northwestern part of China,rational and efficient management of irrigation and nitrogen significantly affects the intensive production of greenhouse cucumbers(Cucumis sativus L).To evaluate the effects of diffe... In the northwestern part of China,rational and efficient management of irrigation and nitrogen significantly affects the intensive production of greenhouse cucumbers(Cucumis sativus L).To evaluate the effects of different combinations of water use and nitrogen(N)on yield,quality,and profitability of the greenhouse cucumbers that planted in 2018 Spring,nine combined treatments were applied.Results indicated the optimal irrigation and nitrogen demands for yield,quality and other indicators were different.The irrigation amount significantly affected the yield,and the yield gradually increased with increasing in irrigation.Single fruit weight(SFW)was significantly affected by the amount of irrigation,nitrogen and their interactions,and the higher amounts of N and irrigation were beneficial to the increase of SFW.The partial factor productivity of the applied N(PFPN)gradually increased with the nitrogen amount decline.Irrigation water use efficiency(IWUE)was closely related to the amount of irrigation.The higher irrigation amount would lead to the lower IWUE.When the amounts of irrigation and nitrogen were at an intermediate level,the content of vitamin C(VC)reached the maximum.As the amount of nitrogen was increased or irrigation was decreased,the Nitrate content(NC)would increase.Free amino acid(FAA)and NC followed a similar variation.When the amounts of irrigation and nitrogen both were at medium levels,the total soluble sugar concentration(TSSC)reached the highest.The multi-level fuzzy evaluation method was used to evaluate different indicators of cucumber.The weights of indicators in the first and second layer were determined by analytic hierarchy process(AHP)and entropy weight method,respectively.Then the fuzzy algorithm was used to comprehensively evaluate all the treatments.The evaluation results show that T4(irrigation,1957.6 m3/hm2;N,210 kg/hm2)is the best strategy for greenhouse cucumber irrigation and nitrogen management in the northwestern part of China. 展开更多
关键词 Cucumis sativus L water and nitrogen coupling YIELD PFPN IWUE quality multi-level fuzzy evaluation
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Dynamic Evaluation and Analysis of Regional Innovation Capability in Eastern China from the Perspective of High-quality Development 被引量:2
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作者 Linming XU Jincheng LU +1 位作者 Meijuan LI Lerong HE 《Journal of Systems Science and Information》 CSCD 2021年第6期608-626,共19页
The economy of China has turned to the stage of high-quality development. In this sense,the connotation of regional innovation capacity should reflect more aspects, such as better economic effectiveness, people-center... The economy of China has turned to the stage of high-quality development. In this sense,the connotation of regional innovation capacity should reflect more aspects, such as better economic effectiveness, people-centered philosophy of development and better living conditions. This study aims at establishing the evaluation index system of regional innovation capacity under high-quality perspective.Then the dynamic evaluation method based on gray correlation degree and TOPSIS is improved. And the improved method is applied to evaluate the regional innovation capacity under high-quality development perspective. The results show that: 1) The regional innovation capacity of Jiangsu, Zhejiang,Shanghai and Guangdong under high-quality development perspective is better than other regions,while the regional innovation capacity of Beijing-Tianjin-Hebei is imbalanced. Regional innovation capability of Fujian, Shandong, and Hainan from a high-quality perspective is at the middle and lower levels. 2) From the perspective of development trends, the gap of regional innovation capacity between Beijing, Jiangsu, Zhejiang, Shanghai, Guangdong and Fujian, Hebei, Shandong is gradually narrowing.3) An in-depth analysis of the regional innovation capability of the eastern provinces and cities from the perspective of high-quality development through different dimensions shows that Beijing, Guangdong, Jiangsu perform well in all dimensions, while Fujian and Hainan need to pay more attention to innovation input and the creation of a better innovation environment to enhance innovation output and promote innovation effectiveness. At last, based on above analysis, relevant policy recommendations are proposed. 展开更多
关键词 regional innovation capability high-quality development TOPSIS gray correlation degree dynamic evaluation method
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Data fusion of radar and IFF for aircraft identification 被引量:2
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作者 Yuanquan Tan dianyu Yang +1 位作者 Liangchao Li Jintao Xiong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期715-722,共8页
The problem of identification of friend-or-foe aircraft in the actual application condition is addressed.A hybrid algorithm combining fuzzy neutral network with probability factor(FNNP),multi-level fuzzy comprehensi... The problem of identification of friend-or-foe aircraft in the actual application condition is addressed.A hybrid algorithm combining fuzzy neutral network with probability factor(FNNP),multi-level fuzzy comprehensive evaluation and the DempsterShafer(D-S) theory is proposed.This hybrid algorithm constructs a complete process from generating the fuzzy database to the final identification,realizes the identification of friend-or-foe automatically if the training samples or expert’s experience can be obtained,and reduces the effect of uncertainties in the process of identification.At the same time,the whole algorithm can update the identification result with the augment of observations.The performance of the proposed algorithm is assessed by simulations.Results show that the proposed algorithm can successfully deduce the aircraft’s identity even if the observations have measurement errors. 展开更多
关键词 fuzzy neutral network with probability factor(FNNP) multi-level fuzzy comprehensive evaluation Dempster-Shafer(D-S) theory identification of friend-or-foe(IFF)
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Research on Global Higher Education Quality Based on BP Neural Network and Analytic Hierarchy Process 被引量:2
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作者 Mei Yuan Chunyang Li 《Journal of Computer and Communications》 2021年第6期158-173,共16页
Having a universal, fair, democratic and practical higher education system plays a particularly important role in the future development of the country. However, the higher education system in various countries is une... Having a universal, fair, democratic and practical higher education system plays a particularly important role in the future development of the country. However, the higher education system in various countries is uneven. It is of great significance to establish a general evaluation system for the development of global education. In this paper, 23 indicators are preliminarily selected from the education data of Universitas 21 and Global Statistical Yearbook. After the gray correlation analysis, 12 indicators were selected. On the one hand, principal component analysis is used to reduce the dimension of these 12 indicators in 50 countries, and the first four principal components with cumulative contribution rate of 99% are finally selected as the input parameters of BP neural network. On the other hand, 12 indicators are divided into four aspects as the standard of scheme decision-making. Finally, a higher education quality evaluation and decision-making model based on BP neural network and analytic hierarchy process are established. Then eight countries are selected to use the model to evaluate their current higher education quality. Based on the input and evaluation results of the four aspects of higher education in various countries, the analytic hierarchy process is used to make program decision, and several improvement suggestions are put forward for the current education policies of various countries. 展开更多
关键词 Higher Education gray Correlation Analysis Main Component Analysis BP Neural Network Hierarchical Analysis evaluation Index System
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基于区间灰度的区域物流配送中心选址实证分析
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作者 刘文强 《物流技术》 北大核心 2014年第9期246-248,共3页
结合区域物流配送中心选址评价中存在的不确定性和评价信息量获取不充足性,提出采用语言标度和灰度构成的有序对作为评价标度,并利用OWA算子获得评价指标权重和组合权重,给出一种区域物流配送中心选址方法,最后实证分析了该方法的可行... 结合区域物流配送中心选址评价中存在的不确定性和评价信息量获取不充足性,提出采用语言标度和灰度构成的有序对作为评价标度,并利用OWA算子获得评价指标权重和组合权重,给出一种区域物流配送中心选址方法,最后实证分析了该方法的可行性和科学性。 展开更多
关键词 区间灰度 评价标度 区域物流 配送中心 选址方法
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Research into selection evaluation system on co-mining of“the three gas”in coal series stratum
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作者 Qiang Liu Jianjun Liu Bing Liang 《Petroleum》 2018年第4期444-451,共8页
Along with the continuously go deep into of the research on coal series stratum,unconventional coalderived gas gets more attention,including coalbed methane,shale gas and tight sandstone gas.However,selection evaluati... Along with the continuously go deep into of the research on coal series stratum,unconventional coalderived gas gets more attention,including coalbed methane,shale gas and tight sandstone gas.However,selection evaluation as the basis and prerequisite for the exploration and development of unconventional coal-derived gas has great significance.The purpose of this paper is to set up a selection evaluation system,and this system is called selection evaluation on co-mining of“the three gas”in coal series stratum.If a basin exists these three gases at the same time,then we can use this evaluation system to evaluate this type of basin and choose dessert area,finally,for co-mining of“the three gas”in coal series stratum provide guidance.By choosing the main control factors of coalbed methane,shale gas and tight sandstone gas,and based on fuzzy mathematics,analytic hierarchy process theory and multilevel fuzzy comprehensive evaluation theory to research selection evaluation system on co-mining of“the three gas”in coal series stratum.Finally,26 main control factors are selected,and then the index system is set up;in addition,by calculating the weight and establishing the membership function and evaluation set,and then selection evaluation system on co-mining of“the three gas”in coal series stratum with a four layer index is established.This paper can provide a theoretical basis and engineering guidance for unconventional gas exploration and development. 展开更多
关键词 Geological engineering Selection evaluation system multi-level fuzzy mathematics “The three gas”in coal series stratum
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Outdoor relative radiometric calibration method using gray scale targets 被引量:2
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作者 DUAN YiNi YAN Lei +2 位作者 YANG Bin JING Xin CHEN Wei 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第7期1825-1834,共10页
The radiometric calibration of remote sensors is a basis and prerequisite of information quantification in remote sensing. This paper proposes a method for outdoor relative radiometric calibration using gray scale tar... The radiometric calibration of remote sensors is a basis and prerequisite of information quantification in remote sensing. This paper proposes a method for outdoor relative radiometric calibration using gray scale targets. In this method, the idea of two substitutions is adopted. Sunlight is used to replace the integrating sphere light source, and gray scale targets are used to re-place the diffuser. In this way, images at different radiance levels obtained outdoors can calculate the relative radiometric cali-bration coefficients using the least square method. The characteristics of this method are as follows. Firstly, compared with la-boratory calibration, it greatly reduces the complexity of the calibration method and the test cost. Secondly, compared with the existing outdoor relative radiometric calibration of a single radiance level, it uses test images of different radiance levels to re-duce errors. Thirdly, it is easy to operate with fewer environmental requirements, has obvious advantages in the rapid calibra-tion of airborne remote sensors before or after flight and is practical in engineering. This paper theoretically and experimental-ly proves the feasibility of this method. Calibration experiments were conducted on the wide-view multispectral imager (WVMI) using this method, and the precision of this method was evaluated by analyzing the corrected images of large uniform targets on ground. The experiment results have demonstrated that the new method is effective and its precision meets the re-quirement of the absolute radiometric calibration. 展开更多
关键词 RELATIVE radiometric calibration RELATIVE radiometric CORRECTION precision evaluation gray scale TARGET
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京津冀城市韧性的时空演变特征及动态模拟研究 被引量:4
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作者 牟旭方 方创琳 杨智奇 《Journal of Geographical Sciences》 SCIE CSCD 2022年第9期1766-1790,共25页
The continuous growth of urban agglomerations in China has increased their complexity as well as vulnerability. In this context, urban resilience is critical for the healthy and sustainable development of urban agglom... The continuous growth of urban agglomerations in China has increased their complexity as well as vulnerability. In this context, urban resilience is critical for the healthy and sustainable development of urban agglomerations. Focusing on the Beijing-Tianjin-Hebei(BTH) urban agglomeration, this study constructs an urban resilience evaluation system based on four subsystems: economy, society, infrastructure, and ecology. It uses the entropy method to measure the urban resilience of the BTH urban agglomeration from 2000 to 2018.Theil index, standard deviation ellipse, and gray prediction model GM(1,1) methods are used to examine the spatio-temporal evolution and dynamic simulation of urban resilience in this urban agglomeration. Our results show that the comprehensive evaluation index for urban resilience in the BTH urban agglomeration followed a steady upward trend from 2000 to 2018,with an average annual growth rate of 6.72%. There are significant differences in each subsystem’s contribution to urban resilience;overall, economic resilience is the main factor affecting urban resilience, with an average annual growth rate of 8.06%. Spatial differences in urban resilience in the BTH urban agglomeration have decreased from 2000 to 2018, showing the typical characteristic of being greater in the central core area and lower in the surrounding non-core areas. The level of urban resilience in the BTH urban agglomeration is forecast to continue increasing over the next ten years. However, there are still considerable differences between the cities. Policy factors will play a positive role in promoting the resilience level. Based on the evaluation results, corresponding policy recommendations are put forwar to provide scientific data support and a theoretical basis for the resilience construction of the BTH urban agglomeration. 展开更多
关键词 urban agglomeration urban resilience Beijing-Tianjin-Hebei(BTH) evaluation system gray prediction model
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