In this paper,a fault location method for the petal-shaped distribution network(PSDN)with inverter-interfaced distributed generators(IIDGs)is proposed to shorten the time of manual inspection.In order to calculate the...In this paper,a fault location method for the petal-shaped distribution network(PSDN)with inverter-interfaced distributed generators(IIDGs)is proposed to shorten the time of manual inspection.In order to calculate the fault position,the closed-loop structure of the PSDN is skillfully exploited,and the common control strategies of IIDGs are considered.For asymmetrical faults,a fault line identification formula based on the negative-sequence current phase differences is presented,and a fault location formula only utilizing the negative-sequence current amplitudes is derived to calculated the fault position.For symmetrical faults,the positive-sequence current at both ends of lines and the current output from IIDGs are used to identify the fault line,and the positive-sequence current on multiple lines are used to pinpoint the fault position.In this method,corresponding current phasors are separated into amplitudes and phases to satisfy the limitation of communication level.The simulation results show that the error is generally less than 1%,and the accuracy of the proposed method is not affected by the fault type,fault position,fault resistance,load current,and the IIDG penetration.展开更多
[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the rela...[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the relation of leaf stomatal density （SD）, length （SL） and width （ SW）, stomatal conductance （g,）, photosynthetic rate （ Pn ）, transpiration rate （ Tr） to grain yield per plant and index of drought resistance （IDR） on the 10th and 20t＂ day after anthesis under the conditions of drought stress and normal irrigation were discussed by the methods of correlation analysis and path analysis. [ Result] Under the two water conditions, the correlations of these stomatal traits with yield components and IDR were mostly not significant on the 10t＂ day after anthesis, but there were significantly positive correlations between thousand kernel weight （TKW） and these traits on the 20^th day after anthesis. Path analysis showed that g,, Pn and Tt, were main factors affecting yield per plant （YPP） and IDR, and they had stron- ger direct effects on YPP and IDR, while their indirect interaction was also strong. The direct effects of SD, SL and SW on YPP and IDR were small, as well as their indirect action among SD, SL and SW. On the other hand, the correlations between SD and SL were significant, and the correlations of SL with SW, gn, P, and Tt, were extremely significant on the 10th and 20th day after anthesis under the two water conditions. However, the correlations of SD and SL with g,, P,, and Tr changed with water conditions or growth stages, showing that water conditions or growth stages had great effects on the correlations between two traits. Therefore, it is not always a good means to improve stomatal conductance, photosynthetic rate and transpiration rate and hence promote wheat yield by selecting stomatal density and size. [ Conclusion] The research could provide scientific references for revealing the roles of leaf stomatal traits in wheat breeding for drought resistance.展开更多
The existence of bounded weak solutions,to a class of nonlinear elliptic equations with variable exponents,is investigated in this article.A uniform a priori L^(∞) estimate is obtained by the De Giorgi iterative tech...The existence of bounded weak solutions,to a class of nonlinear elliptic equations with variable exponents,is investigated in this article.A uniform a priori L^(∞) estimate is obtained by the De Giorgi iterative tech-nique.Thanks to the weak convergence method and Minty's trick,the existence result is proved through limit process.展开更多
基金supported by State Grid Science and Technology Project:Research on Key Protection Technologies for New-type Urban Distribution Network with Controllable Sources and Loads(5100-201913019A-0-0-00).
文摘In this paper,a fault location method for the petal-shaped distribution network(PSDN)with inverter-interfaced distributed generators(IIDGs)is proposed to shorten the time of manual inspection.In order to calculate the fault position,the closed-loop structure of the PSDN is skillfully exploited,and the common control strategies of IIDGs are considered.For asymmetrical faults,a fault line identification formula based on the negative-sequence current phase differences is presented,and a fault location formula only utilizing the negative-sequence current amplitudes is derived to calculated the fault position.For symmetrical faults,the positive-sequence current at both ends of lines and the current output from IIDGs are used to identify the fault line,and the positive-sequence current on multiple lines are used to pinpoint the fault position.In this method,corresponding current phasors are separated into amplitudes and phases to satisfy the limitation of communication level.The simulation results show that the error is generally less than 1%,and the accuracy of the proposed method is not affected by the fault type,fault position,fault resistance,load current,and the IIDG penetration.
基金Supported by the Study Abroad Foundation of Shanxi Province,China( 2010048)CGIAR Challenge Program Project ( GCP) ( G7010.02.01-7)Special Foundation for Talent Introduction And Development of Shanxi Province,China ( 2011)
文摘[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the relation of leaf stomatal density （SD）, length （SL） and width （ SW）, stomatal conductance （g,）, photosynthetic rate （ Pn ）, transpiration rate （ Tr） to grain yield per plant and index of drought resistance （IDR） on the 10th and 20t＂ day after anthesis under the conditions of drought stress and normal irrigation were discussed by the methods of correlation analysis and path analysis. [ Result] Under the two water conditions, the correlations of these stomatal traits with yield components and IDR were mostly not significant on the 10t＂ day after anthesis, but there were significantly positive correlations between thousand kernel weight （TKW） and these traits on the 20^th day after anthesis. Path analysis showed that g,, Pn and Tt, were main factors affecting yield per plant （YPP） and IDR, and they had stron- ger direct effects on YPP and IDR, while their indirect interaction was also strong. The direct effects of SD, SL and SW on YPP and IDR were small, as well as their indirect action among SD, SL and SW. On the other hand, the correlations between SD and SL were significant, and the correlations of SL with SW, gn, P, and Tt, were extremely significant on the 10th and 20th day after anthesis under the two water conditions. However, the correlations of SD and SL with g,, P,, and Tr changed with water conditions or growth stages, showing that water conditions or growth stages had great effects on the correlations between two traits. Therefore, it is not always a good means to improve stomatal conductance, photosynthetic rate and transpiration rate and hence promote wheat yield by selecting stomatal density and size. [ Conclusion] The research could provide scientific references for revealing the roles of leaf stomatal traits in wheat breeding for drought resistance.
基金supported in part by the National Natural Science Foundation of China(Grant No.11901131)Youth science and technology talent growth project in Guizhou Province for ordinary institutions of higher learning(KY[2021]142).
文摘The existence of bounded weak solutions,to a class of nonlinear elliptic equations with variable exponents,is investigated in this article.A uniform a priori L^(∞) estimate is obtained by the De Giorgi iterative tech-nique.Thanks to the weak convergence method and Minty's trick,the existence result is proved through limit process.
