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Study on the Post-evaluation of Environmental Planning Based on Logical Framework Approach 被引量:2
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作者 CHEN Yu-xian DONG Ze-qin 《Meteorological and Environmental Research》 CAS 2011年第2期1-5,9,共6页
[Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province fo... [Objective] The aim was to conduct post-evaluation on environmental planning by means of logical framework approach. [Method] Taking environmental planning during '11th Five-year Plan' in a certain province for example, by means of logical framework approach (LFA), the post-evaluation on environmental planning was carried out from the aspects of evaluation content, index system, implementation steps, evaluation feedback and input-output analysis of environmental planning. [Result] The post-evaluation on environmental planning by means of LFA achieved expected purpose and various indexes at different stages of environmental planning was assessed, and then corresponding countermeasures were put forward according to the problems which were found by problem tree of environmental planning project. [Conclusion] The study could provide theoretical references for the post-evaluation on environmental planning in future. 展开更多
关键词 logical framework approach Environmental planning during '11th Five-year Plan' POST-EVALUATION China
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Ingredients-based Methodology and Fuzzy Logic Combined Short-Duration Heavy Rainfall Short-Range Forecasting:An Improved Scheme
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作者 TIAN Fu-you XIA Kun +2 位作者 SUN Jian-hua ZHENG Yong-guang HUA Shan 《Journal of Tropical Meteorology》 SCIE 2024年第3期241-256,共16页
Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the mos... Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the most common convective weather phenomena that can cause severe damage.Short-range forecasting of SHR is an important part of operational severe weather prediction.In the present study,an improved objective SHR forecasting scheme was developed by adopting the ingredients-based methodology and using the fuzzy logic approach.The 1.0°×1.0°National Centers for Environmental Prediction(NCEP)final analysis data and the ordinary rainfall(0.1-19.9 mm h-1)and SHR observational data from 411 stations were used in the improved scheme.The best lifted index,the total precipitable water,the 925 hPa specific humidity(Q 925),and the 925 hPa divergence(DIV 925)were selected as predictors based on objective analysis.Continuously distributed membership functions of predictors were obtained based on relative frequency analysis.The weights of predictors were also objectively determined.Experiments with a typhoon SHR case and a spring SHR case show that the main possible areas could be captured by the improved scheme.Verification of SHR forecasts within 96 hours with NCEP global forecasts 1.0°×1.0°data initiated at 08:00 Beijing Time during the warm seasons in 2015 show the results were improved from both deterministic and probabilistic perspectives.This study provides an objectively feasible choice for short-range guidance forecasts of SHR.The scheme can be applied to other convective phenomena. 展开更多
关键词 ingredients-based methodology fuzzy logic approach probability of short-duration heavy rainfall(SHR) improved forecasting scheme objectively obtained membership functions
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Vehicle height and leveling control of electronically controlled air suspension using mixed logical dynamical approach 被引量:7
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作者 SUN Xiao Qiang CAI Ying Feng +2 位作者 YUAN Chao Chun WANG Shao Hua CHEN Long 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第12期1814-1824,共11页
Vehicle height and leveling control of electronically controlled air suspension(ECAS) still poses theoretical challenges for researchers that have not been adequately addressed in prior research. This paper investigat... Vehicle height and leveling control of electronically controlled air suspension(ECAS) still poses theoretical challenges for researchers that have not been adequately addressed in prior research. This paper investigates the design and verification of a new controller to adjust the vehicle height and to regulate the roll and pitch angles of the vehicle body(leveling control) during the height adjustment procedures. A nonlinear mechanism model of the vehicle height adjustment system is formulated to describe the dynamic behaviors of the system. By using mixed logical dynamical(MLD) approach, a novel control strategy is proposed to adjust the vehicle height by controlling the on-off statuses of the solenoid valves directly. On this basis, a correction algorithm is also designed to regulate the durations of the on-off statuses of the solenoid valves based on pulse width modulated(PWM) technology, thus the effective leveling control of the vehicle body can be guaranteed. Finally, simulations and vehicle tests results are presented to demonstrate the effectiveness and applicability of the proposed control methodology. 展开更多
关键词 electronically controlled air suspension vehicle height control leveling control hybrid system mixed logical dynamical approach
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A New Approach to Database Auto-Design by Logic
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作者 徐洁盘 王磊 《Journal of Computer Science & Technology》 SCIE EI CSCD 1991年第2期201-204,共4页
The database auto-design is an important problem in database research.In this paper we propose some new ideas and an approach called“logic approach”to implement the database auto-design.Given a relational scheme and... The database auto-design is an important problem in database research.In this paper we propose some new ideas and an approach called“logic approach”to implement the database auto-design.Given a relational scheme and a set of the functional dependencies for the relation we can obtain all of the functional dependencies and key for the relation and determine the normal form the relation satisfies. 展开更多
关键词 AUTO A New approach to Database Auto-Design by Logic DESIGN
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