This paper presents a novel robust S transform algorithm based on the clipping method to process signals corrupted by impulsive noise.The proposed algorithm is introduced to determine the clipping threshold value acco...This paper presents a novel robust S transform algorithm based on the clipping method to process signals corrupted by impulsive noise.The proposed algorithm is introduced to determine the clipping threshold value according to the characteristics of the signal samples.Signals in various impulsive noise models are considered to illustrate that the robust S transform can achieve better performance than the standard S transform.Moreover,mean square errors for instantaneous frequency estimation of the robust S transform are compared with that of the standard S transform,showing that the robust S transform can achieve significantly improved instantaneous frequency estimation for the signals in impulsive noise.展开更多
BACKGROUND We recently developed a new endoscopic closure technique using only conventional endo-clips for colorectal lesions.Little is known about the feasibility of the endoscopic mucosa-submucosa clip closure metho...BACKGROUND We recently developed a new endoscopic closure technique using only conventional endo-clips for colorectal lesions.Little is known about the feasibility of the endoscopic mucosa-submucosa clip closure method for gastric lesions.AIM To elucidate the efficacy of the endoscopic mucosa-submucosa clip closure method after gastric endoscopic submucosal dissection(ESD).METHODS Twenty-two patients who underwent gastric ESD and mucosa-submucosa clip closure were included in this study.In this method,endo-clips are placed at the edges of a mucosal defect.Additional endo-clips are then applied in the same way to facilitate reduction of the defect size.Additional endo-clips are applied to both sides of the mucosal defect.Complete closure can be achieved.We have also developed a“location score”and“closure difficulty index”for assessment purposes.RESULTS Complete closure was achieved in 68.2%of the patients(15/22).The location score in the failure group was significantly larger than that in the complete closure group(P=0.023).The closure difficulty index in the failure group was significantly higher than that in the complete closure group(P=0.007).When the cutoff value of the closure difficulty index was set at 99,the high closure difficulty index predicted failure with a sensitivity of 57.1%,specificity of 100%,and accuracy of 86.3%.CONCLUSION The endoscopic mucosa-submucosa clip closure method was unreliable after gastric ESD,especially in cases with a high closure difficulty index.展开更多
This paper presents an explicit formula based on reparameterization technique for progressively computing a simple root of a smooth function,which may have wide applications in robotics,geomagnetic navigation,geometri...This paper presents an explicit formula based on reparameterization technique for progressively computing a simple root of a smooth function,which may have wide applications in robotics,geomagnetic navigation,geometric processing and computer graphics.Comparing with Newton-like method,it can achieve convergence rate 2 by adding one more functional evaluation,improve the computational stability and ensure the convergence,and also obtain higher convergence rate and higher efficiency index.Compared with clipping methods for polynomials,it doesn't need to bound the polynomials,directly bound the roots and can also work well for non-polynomial functions with much higher computational efficiency.Comparing with previous progressive methods,it achieves a much higher computational efficiency and is extended to solve bivariate equation system.Numerical examples show its much better performance on approximation error,computational efficiency and computational stability.展开更多
基金supported by the National Natural Science Foundation of China(6110216461272224)the Scientific Research Fund of Hangzhou Normal University(2011QDL021)
文摘This paper presents a novel robust S transform algorithm based on the clipping method to process signals corrupted by impulsive noise.The proposed algorithm is introduced to determine the clipping threshold value according to the characteristics of the signal samples.Signals in various impulsive noise models are considered to illustrate that the robust S transform can achieve better performance than the standard S transform.Moreover,mean square errors for instantaneous frequency estimation of the robust S transform are compared with that of the standard S transform,showing that the robust S transform can achieve significantly improved instantaneous frequency estimation for the signals in impulsive noise.
文摘BACKGROUND We recently developed a new endoscopic closure technique using only conventional endo-clips for colorectal lesions.Little is known about the feasibility of the endoscopic mucosa-submucosa clip closure method for gastric lesions.AIM To elucidate the efficacy of the endoscopic mucosa-submucosa clip closure method after gastric endoscopic submucosal dissection(ESD).METHODS Twenty-two patients who underwent gastric ESD and mucosa-submucosa clip closure were included in this study.In this method,endo-clips are placed at the edges of a mucosal defect.Additional endo-clips are then applied in the same way to facilitate reduction of the defect size.Additional endo-clips are applied to both sides of the mucosal defect.Complete closure can be achieved.We have also developed a“location score”and“closure difficulty index”for assessment purposes.RESULTS Complete closure was achieved in 68.2%of the patients(15/22).The location score in the failure group was significantly larger than that in the complete closure group(P=0.023).The closure difficulty index in the failure group was significantly higher than that in the complete closure group(P=0.007).When the cutoff value of the closure difficulty index was set at 99,the high closure difficulty index predicted failure with a sensitivity of 57.1%,specificity of 100%,and accuracy of 86.3%.CONCLUSION The endoscopic mucosa-submucosa clip closure method was unreliable after gastric ESD,especially in cases with a high closure difficulty index.
基金Supported by the National Natural Science Foundation of China (61972120)。
文摘This paper presents an explicit formula based on reparameterization technique for progressively computing a simple root of a smooth function,which may have wide applications in robotics,geomagnetic navigation,geometric processing and computer graphics.Comparing with Newton-like method,it can achieve convergence rate 2 by adding one more functional evaluation,improve the computational stability and ensure the convergence,and also obtain higher convergence rate and higher efficiency index.Compared with clipping methods for polynomials,it doesn't need to bound the polynomials,directly bound the roots and can also work well for non-polynomial functions with much higher computational efficiency.Comparing with previous progressive methods,it achieves a much higher computational efficiency and is extended to solve bivariate equation system.Numerical examples show its much better performance on approximation error,computational efficiency and computational stability.
