The Taylor model arithmetic is introduced to deal with uncertainty.The uncertainty of model parameters is described by Taylor models and each variable in functions is replaced with the Taylor model(TM).Thus,time domai...The Taylor model arithmetic is introduced to deal with uncertainty.The uncertainty of model parameters is described by Taylor models and each variable in functions is replaced with the Taylor model(TM).Thus,time domain simulation under uncertainty is transformed to the integration of TM-based differential equations.In this paper,the Taylor series method is employed to compute differential equations;moreover,power system time domain simulation under uncertainty based on Taylor model method is presented.This method allows a rigorous estimation of the influence of either form of uncertainty and only needs one simulation.It is computationally fast compared with the Monte Carlo method,which is another technique for uncertainty analysis.The proposed method has been tested on the 39-bus New England system.The test results illustrate the effectiveness and practical value of the approach by comparing with the results of Monte Carlo simulation and traditional time domain simulation.展开更多
It is suggested in this paper that the famous Taylor’s model for the compdrition and evolution of the continental crust consists of three closely related key links. These links include an assumption that the surficia...It is suggested in this paper that the famous Taylor’s model for the compdrition and evolution of the continental crust consists of three closely related key links. These links include an assumption that the surficial environment has no effect on the sedimentary REE patterns and the REE patterns in shales can reflect the composition of their provenancel a discovery about the discrepancy of sedimentary REE patterns between Archean and Proterozoic, and a deduc-tion that there was a global scale K-granitoid event at the end of the Archean. Based on a de-tailed discussion, this paper substantially negates the rationality of the Taylor’s model and ar-gues that its three critical links be three great errors indeed. Moreover, some other deficiencies or problems it confronts are described in this paper. The authors suggest that what led to the errors involved in the Taylor’s model is its wrongly neglecting the effect of the sedimentary en-vironment on the chemical composition of sediments, and that the environment should be an important factor affecting the distribution patterns of trace elements in the sediments.展开更多
利用反向Taylor杆撞击实验和数值模拟方法研究了30CrMnSiNi2A钢在高应变率冲击下的动态特性。首先,在Taylor杆冲击实验的基础上,采用Johnson-Cook本构模型和失效模型,对30CrMnSiNi2A钢的反向Taylor杆撞击进行了数值模拟,并将数值模拟结...利用反向Taylor杆撞击实验和数值模拟方法研究了30CrMnSiNi2A钢在高应变率冲击下的动态特性。首先,在Taylor杆冲击实验的基础上,采用Johnson-Cook本构模型和失效模型,对30CrMnSiNi2A钢的反向Taylor杆撞击进行了数值模拟,并将数值模拟结果与实验得到的杆件自由面速度曲线进行对比验证,两者吻合良好。然后,研究了不同长径比的30CrMnSiNi2A钢杆件对反向Taylor杆撞击实验中任意反射面激光干涉测速技术(velocity interferometer system for any reflector,VISAR)测试结果的影响,得到了适用于VISAR测试的Taylor杆长径比范围。最后,运用应力三轴度及损伤度分析了Taylor杆的断裂破坏机理和变形模式,得到了镦粗、蘑菇状变形、花瓣状开裂3种变形模式,并分析了杆件断裂破坏的原因。结果表明:Taylor杆撞击端中心破坏是由于材料受压引起,而撞击端边缘开裂是由于材料处于拉伸状态造成的,且断裂先从边缘开始。展开更多
Sandpile phenomena in dynamic systems in the vicinity of criticality always appeal to a sudden break of stability with avalanches of different sizes due to minor perturbations. We can view the intervention of the Cent...Sandpile phenomena in dynamic systems in the vicinity of criticality always appeal to a sudden break of stability with avalanches of different sizes due to minor perturbations. We can view the intervention of the Central Banks on the rate of interest as a perturbation of the economic system. It is an induced perturbation to a system that fare in vicinity of criticality according to the conditions of stability embedded in the equations of the neoclassical model. An alternative reading of the Taylor Rule is proposed in combination with the Sandpile paradigm to give an account of the economic crisis as an event like an avalanche, that can be triggered by a perturbation, as is the intervention of the Central Bank on the interest rate.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.50477035).
文摘The Taylor model arithmetic is introduced to deal with uncertainty.The uncertainty of model parameters is described by Taylor models and each variable in functions is replaced with the Taylor model(TM).Thus,time domain simulation under uncertainty is transformed to the integration of TM-based differential equations.In this paper,the Taylor series method is employed to compute differential equations;moreover,power system time domain simulation under uncertainty based on Taylor model method is presented.This method allows a rigorous estimation of the influence of either form of uncertainty and only needs one simulation.It is computationally fast compared with the Monte Carlo method,which is another technique for uncertainty analysis.The proposed method has been tested on the 39-bus New England system.The test results illustrate the effectiveness and practical value of the approach by comparing with the results of Monte Carlo simulation and traditional time domain simulation.
文摘It is suggested in this paper that the famous Taylor’s model for the compdrition and evolution of the continental crust consists of three closely related key links. These links include an assumption that the surficial environment has no effect on the sedimentary REE patterns and the REE patterns in shales can reflect the composition of their provenancel a discovery about the discrepancy of sedimentary REE patterns between Archean and Proterozoic, and a deduc-tion that there was a global scale K-granitoid event at the end of the Archean. Based on a de-tailed discussion, this paper substantially negates the rationality of the Taylor’s model and ar-gues that its three critical links be three great errors indeed. Moreover, some other deficiencies or problems it confronts are described in this paper. The authors suggest that what led to the errors involved in the Taylor’s model is its wrongly neglecting the effect of the sedimentary en-vironment on the chemical composition of sediments, and that the environment should be an important factor affecting the distribution patterns of trace elements in the sediments.
文摘利用反向Taylor杆撞击实验和数值模拟方法研究了30CrMnSiNi2A钢在高应变率冲击下的动态特性。首先,在Taylor杆冲击实验的基础上,采用Johnson-Cook本构模型和失效模型,对30CrMnSiNi2A钢的反向Taylor杆撞击进行了数值模拟,并将数值模拟结果与实验得到的杆件自由面速度曲线进行对比验证,两者吻合良好。然后,研究了不同长径比的30CrMnSiNi2A钢杆件对反向Taylor杆撞击实验中任意反射面激光干涉测速技术(velocity interferometer system for any reflector,VISAR)测试结果的影响,得到了适用于VISAR测试的Taylor杆长径比范围。最后,运用应力三轴度及损伤度分析了Taylor杆的断裂破坏机理和变形模式,得到了镦粗、蘑菇状变形、花瓣状开裂3种变形模式,并分析了杆件断裂破坏的原因。结果表明:Taylor杆撞击端中心破坏是由于材料受压引起,而撞击端边缘开裂是由于材料处于拉伸状态造成的,且断裂先从边缘开始。
文摘Sandpile phenomena in dynamic systems in the vicinity of criticality always appeal to a sudden break of stability with avalanches of different sizes due to minor perturbations. We can view the intervention of the Central Banks on the rate of interest as a perturbation of the economic system. It is an induced perturbation to a system that fare in vicinity of criticality according to the conditions of stability embedded in the equations of the neoclassical model. An alternative reading of the Taylor Rule is proposed in combination with the Sandpile paradigm to give an account of the economic crisis as an event like an avalanche, that can be triggered by a perturbation, as is the intervention of the Central Bank on the interest rate.