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Improvement of Ecological Footprint Method and Application in Henan Province
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作者 Niu Shuhai, Jin Fengjun & Liu Yi Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2005年第1期44-48,共5页
The measure of sustainable development has always been an important and difficulty subject, and the major evaluation model has three types: indicators based on system theory and methods, indicators relied on economic ... The measure of sustainable development has always been an important and difficulty subject, and the major evaluation model has three types: indicators based on system theory and methods, indicators relied on economic valuation of the environment, sustainability indicators including biophysical assessments. The ecological footprint analysis initiated by William E. Rees, one of the indicators including biophysical assessments, gets rid of the defects of the other models. Ecological footprint has gradually become popular on account of the measuring indexes based on scientific theory, innovative thought-way and its wide adaptability. This paper introduces the conception and computation method, making a progress and making up for the method of ecological footprint, and finally, makes an application analyses through Henan province regional sustainable development. 展开更多
关键词 sustainable development ecological footprint input/occupancy-output model integrated development degree
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Theory of truth degrees of formulas in Lukasiewicz n-valued propositional logic and a limit theorem 被引量:30
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作者 LI Bijing WANG Guojun 《Science in China(Series F)》 2005年第6期727-736,共10页
The concept of truth degrees of formulas in Lukasiewicz n-valued propositional logic Ln is proposed. A limit theorem is obtained, which says that the truth function τ-n induced by truth degrees converges to the integ... The concept of truth degrees of formulas in Lukasiewicz n-valued propositional logic Ln is proposed. A limit theorem is obtained, which says that the truth function τ-n induced by truth degrees converges to the integrated truth function τ when n converges to infinite. Hence this limit theorem builds a bridge between the discrete valued Lukasiewicz logic and the continuous valued Lukasiewicz logic. Moreover, the results obtained in the present paper is a natural generalization of the corresponding results obtained in two-valued propositional logic. 展开更多
关键词 Lukasiewicz n-valued propositional logic truth degree limit theorem integrated truth degree
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Robust Stabilizing Regions of Fractional-order PI~λ Controllers for Fractional-order Systems with Time-delays 被引量:1
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作者 Zhe Gao Li-Rong Zhai Yan-Dong Liu 《International Journal of Automation and computing》 EI CSCD 2017年第3期340-349,共10页
This study focuses on a graphical approach to determine the robust stabilizing regions of fractional-order PIλ(proportional integration) controllers for fractional-order systems with time-delays. By D-decomposition... This study focuses on a graphical approach to determine the robust stabilizing regions of fractional-order PIλ(proportional integration) controllers for fractional-order systems with time-delays. By D-decomposition technique, the existence conditions and calculating method of the real root boundary(RRB) curves, complex root boundary(CRB) curves and infinite root boundary(IRB)lines are investigated for a given stability degree. The robust stabilizing regions in terms of the RRB curves, CRB curves and IRB lines are identified by the proposed criteria in this paper. Finally, two illustrative examples are given to verify the effectiveness of this graphical approach for different stability degrees. 展开更多
关键词 Fractional-order systems time-delays PIλ (proportional integration controllers stabilizing regions stability degree
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SOLVABILITY FOR FRACTIONAL FUNCTIONAL DIFFERENTIAL EQUATION BOUNDARY VALUE PROBLEMS AT RESONANCE
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作者 Xiangkui Zhao Fengjiao An Shasha Guo 《Annals of Applied Mathematics》 2016年第3期322-330,共9页
The paper deals a fractional functional boundary value problems with integral boundary conditions. Besed on the coincidence degree theory, some existence criteria of solutions at resonance are established.
关键词 fractional boundary value problem at resonance coincidence degree theory integral boundary conditions
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