In this paper,a robust adaptive unscented Kalman filter(RAUKF)is developed to mitigate the unfavorable effects derived from uncertainties in noise and in the model.To address these issues,a robust M-estimator is first...In this paper,a robust adaptive unscented Kalman filter(RAUKF)is developed to mitigate the unfavorable effects derived from uncertainties in noise and in the model.To address these issues,a robust M-estimator is first utilized to update the measurement noise covariance.Next,to deal with the effects of model parameter errors while considering the computational complexity and real-time requirements of dynamic state estimation,an adaptive update method is produced.The proposed method is integrated with spherical simplex unscented transformation technology,and then a novel derivative-free filter is proposed to dynamically track the states of the power system against uncertainties.Finally,the effectiveness and robustness of the proposed method are demonstrated through extensive simulation experiments on an IEEE 39-bus test system.Compared with other methods,the proposed method can capture the dynamic characteristics of a synchronous generator more reliably.展开更多
In 2019,preterm births(PTB)accounted for approximately 0.66 million deaths globally.PTB is also associated with a significantly higher risk of mortality and long-term complications for newborns.Long-term studies assoc...In 2019,preterm births(PTB)accounted for approximately 0.66 million deaths globally.PTB is also associated with a significantly higher risk of mortality and long-term complications for newborns.Long-term studies associated several factors,including disruption of immune tolerance and inflammation,with PTB.However,the pathogenesis of PTB remains unclear.Gonadal steroid hormones are critical for pregnancy maintenance and regulation of immune and inflammatory responses.However,it is not clear how unbalanced gonadal steroid hormones,such as imbalanced estrogen/androgen or estrogen/progesterone contribute to PTB.In this review,we discuss how gonadal steroid hormones mediate dysfunction in immune tolerance and inflammatory responses,which are known to promote the occurrence of PTB,and provide insight into PTB prediction.展开更多
This paper proposes an optimal day-ahead opti-mization schedule for gas-electric integrated energy system(IES)considering the bi-directional energy flow.The hourly topology of electric power system(EPS),natural gas sy...This paper proposes an optimal day-ahead opti-mization schedule for gas-electric integrated energy system(IES)considering the bi-directional energy flow.The hourly topology of electric power system(EPS),natural gas system(NGS),energy hubs(EH)integrated power to gas(P2G)unit,are modeled to minimize the day-ahead operation cost of IES.Then,a second-order cone programming(SOCP)method is utilized to solve the optimization problem,which is actually a mixed integer nonconvex and nonlinear programming issue.Besides,cutting planes are added to ensure the exactness of the global optimal solution.Finally,simulation results demonstrate that the proposed optimization schedule can provide a safe,effective and economical day-ahead scheduling scheme for gas-electric IES.展开更多
The effect of phosphorus on mechanical properties and thermal stability of fine-grained GH761 alloy has been investigated.The results show that,when the content of phosphorus is in the range of 0.0007-0.040,there are ...The effect of phosphorus on mechanical properties and thermal stability of fine-grained GH761 alloy has been investigated.The results show that,when the content of phosphorus is in the range of 0.0007-0.040,there are no significant effects on the tensile properties.Phosphorus strongly affects the stress rupture life.The content of 0.023 P results in the longest life in this experiment.Compared with that of the alloy with 0.0007 P,the life is increased more than 2 times in the alloy with 0.023 P.After ageing at 700℃ for 1000 h,the life reduced to some extent.However,phosphorus exhibits the similar effect on the life as before ageing.The tensile properties of the alloy are not influenced by long term ageing obviously.The present results suggested that the optimum content of phosphorus is 0.023.The phosphorus with this content can optimize the precipitates at the grain boundaries and prevent the excessive growth of the precipitates.The combining mechanical properties of GH761 alloy can be largely improved by phosphorus addition combined with grain refinement.展开更多
基金supported by the National Natural Science Foundation of China(No.62073121)the National Natural Science Foundation of China-State Grid Joint Fund for Smart Grid(No.U1966202)the Six Talent Peaks High Level Project of Jiangsu Province(No.2017-XNY-004)。
文摘In this paper,a robust adaptive unscented Kalman filter(RAUKF)is developed to mitigate the unfavorable effects derived from uncertainties in noise and in the model.To address these issues,a robust M-estimator is first utilized to update the measurement noise covariance.Next,to deal with the effects of model parameter errors while considering the computational complexity and real-time requirements of dynamic state estimation,an adaptive update method is produced.The proposed method is integrated with spherical simplex unscented transformation technology,and then a novel derivative-free filter is proposed to dynamically track the states of the power system against uncertainties.Finally,the effectiveness and robustness of the proposed method are demonstrated through extensive simulation experiments on an IEEE 39-bus test system.Compared with other methods,the proposed method can capture the dynamic characteristics of a synchronous generator more reliably.
基金This study was supported by National Natural Science Foundation of China(82001579)Tianjin Health Science and Technology Project(TJWJ2021QN053)+1 种基金Natural Science Foundation of Tianjin(22JCYBJC01110)as well as Open Fund of Tianjin Central Hospital of Gynecology Obstetrics/Tianjin Key Laboratory of human development and reproductive regulation(2022XH10 and 2022XHY03).
文摘In 2019,preterm births(PTB)accounted for approximately 0.66 million deaths globally.PTB is also associated with a significantly higher risk of mortality and long-term complications for newborns.Long-term studies associated several factors,including disruption of immune tolerance and inflammation,with PTB.However,the pathogenesis of PTB remains unclear.Gonadal steroid hormones are critical for pregnancy maintenance and regulation of immune and inflammatory responses.However,it is not clear how unbalanced gonadal steroid hormones,such as imbalanced estrogen/androgen or estrogen/progesterone contribute to PTB.In this review,we discuss how gonadal steroid hormones mediate dysfunction in immune tolerance and inflammatory responses,which are known to promote the occurrence of PTB,and provide insight into PTB prediction.
基金This work was supported in part by the National Natural Science Foundation of China under Grants 61673161 and 51807134and in part by the program of fundamental research of the Siberian Branch of Russian Academy of Sciences and carried out within the framework of the research project III.17.3.1,Reg.No.AAAA-A17-117030310442-8.
文摘This paper proposes an optimal day-ahead opti-mization schedule for gas-electric integrated energy system(IES)considering the bi-directional energy flow.The hourly topology of electric power system(EPS),natural gas system(NGS),energy hubs(EH)integrated power to gas(P2G)unit,are modeled to minimize the day-ahead operation cost of IES.Then,a second-order cone programming(SOCP)method is utilized to solve the optimization problem,which is actually a mixed integer nonconvex and nonlinear programming issue.Besides,cutting planes are added to ensure the exactness of the global optimal solution.Finally,simulation results demonstrate that the proposed optimization schedule can provide a safe,effective and economical day-ahead scheduling scheme for gas-electric IES.
基金supported by the National Natural Science Foundation of China under the contracts of Nos.50271072 & 50471083
文摘The effect of phosphorus on mechanical properties and thermal stability of fine-grained GH761 alloy has been investigated.The results show that,when the content of phosphorus is in the range of 0.0007-0.040,there are no significant effects on the tensile properties.Phosphorus strongly affects the stress rupture life.The content of 0.023 P results in the longest life in this experiment.Compared with that of the alloy with 0.0007 P,the life is increased more than 2 times in the alloy with 0.023 P.After ageing at 700℃ for 1000 h,the life reduced to some extent.However,phosphorus exhibits the similar effect on the life as before ageing.The tensile properties of the alloy are not influenced by long term ageing obviously.The present results suggested that the optimum content of phosphorus is 0.023.The phosphorus with this content can optimize the precipitates at the grain boundaries and prevent the excessive growth of the precipitates.The combining mechanical properties of GH761 alloy can be largely improved by phosphorus addition combined with grain refinement.