The forming process of the flexible ultrathin glasses(UTG)prepared by the redrawing method was numerically simulated using ANSYS Polyflow software.In the forming process by the redrawing method,temperature,viscosity,t...The forming process of the flexible ultrathin glasses(UTG)prepared by the redrawing method was numerically simulated using ANSYS Polyflow software.In the forming process by the redrawing method,temperature,viscosity,transverse and longitudinal velocity distribution of the glasses with different compositions were studied.Furthermore,the influence of these factors on the width and thickness of the flexible glass plate was investigated.It is found that the internal and external heat exchange of glass has a dominant influence on the viscosity variation during the UTG forming process,which is inconsistent with the general viscosity-temperature dependence.The glass that first reaches the lower limit of forming viscosity can significantly resist the shrinking effect caused by surface tension,making the glass wider during the forming.If the original glass width remains unchanged,the glass thickness or feeding speed is reduced,wider and thinner flexible glasses can be produced.展开更多
This paper explores the relationship between costume history research and the redrawing of frescoes of Dunhnang Grottoes. Redrawing frescoes could provide evidences for costume history research, and the research can c...This paper explores the relationship between costume history research and the redrawing of frescoes of Dunhnang Grottoes. Redrawing frescoes could provide evidences for costume history research, and the research can correspondingly help the rodrawing. Redrawing frescoes, for the purpose of costume history study, must comply with some specific rules, which are different from those of other studies. The present study also discusses the methods to distinguish, the original fresco colors that have faded or changed after more than one thousand years.展开更多
The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted s...The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation prediction.This paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,etc.The conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly used.Then,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process noise.Resampling is not believed to be necessary in some researches.However,we find out that resampling can be helpful for an adaptive Kalman gain.This will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers occur.Finally,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it's better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent.展开更多
A new threshold means more than 100 million impoverished people will be eligible for government assistance as China continues to battle poverty The Chinese Government has decided to set the nation’s poverty line at a...A new threshold means more than 100 million impoverished people will be eligible for government assistance as China continues to battle poverty The Chinese Government has decided to set the nation’s poverty line at an annual per-capita net展开更多
基金the National Key Research and Development Program of China(No.2022YFB3603300)。
文摘The forming process of the flexible ultrathin glasses(UTG)prepared by the redrawing method was numerically simulated using ANSYS Polyflow software.In the forming process by the redrawing method,temperature,viscosity,transverse and longitudinal velocity distribution of the glasses with different compositions were studied.Furthermore,the influence of these factors on the width and thickness of the flexible glass plate was investigated.It is found that the internal and external heat exchange of glass has a dominant influence on the viscosity variation during the UTG forming process,which is inconsistent with the general viscosity-temperature dependence.The glass that first reaches the lower limit of forming viscosity can significantly resist the shrinking effect caused by surface tension,making the glass wider during the forming.If the original glass width remains unchanged,the glass thickness or feeding speed is reduced,wider and thinner flexible glasses can be produced.
文摘This paper explores the relationship between costume history research and the redrawing of frescoes of Dunhnang Grottoes. Redrawing frescoes could provide evidences for costume history research, and the research can correspondingly help the rodrawing. Redrawing frescoes, for the purpose of costume history study, must comply with some specific rules, which are different from those of other studies. The present study also discusses the methods to distinguish, the original fresco colors that have faded or changed after more than one thousand years.
基金supported by the National Defense Pre-Research Foundation of China (Grant No 9140A21010908KG0162)CAST Foundation (Grant No 2009-HT-GFKD)
文摘The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation prediction.This paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,etc.The conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly used.Then,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process noise.Resampling is not believed to be necessary in some researches.However,we find out that resampling can be helpful for an adaptive Kalman gain.This will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers occur.Finally,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it's better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent.
文摘A new threshold means more than 100 million impoverished people will be eligible for government assistance as China continues to battle poverty The Chinese Government has decided to set the nation’s poverty line at an annual per-capita net
