Efficient tool condition monitoring techniques help to realize intelligent management of tool life and reduce tool usage costs.In this paper,the influence of different wear degrees of ball-end milling cutters on the t...Efficient tool condition monitoring techniques help to realize intelligent management of tool life and reduce tool usage costs.In this paper,the influence of different wear degrees of ball-end milling cutters on the texture shape of machining tool marks is investigated,and a method is proposed for predicting the wear state(including the position and degree of tool wear)of ball-end milling cutters based on entropy measurement of tool mark texture images.Firstly,data samples are prepared through wear experiments,and the change law of the tool mark texture shape with the tool wear state is analyzed.Then,a two-dimensional sample entropy algorithm is developed to quantify the texture morphology.Finally,the processing parameters and tool attitude are integrated into the prediction process to predict the wear value and wear position of the ball end milling cutter.After testing,the correlation between the predicted value and the standard value of the proposed tool condition monitoring method reaches 95.32%,and the accuracy reaches 82.73%,indicating that the proposed method meets the requirement of tool condition monitoring.展开更多
BACKGROUND The impact of transjugular intrahepatic portosystemic shunt(TIPS)on liver and spleen stiffness remains unclear,as does the association between preoperative liver and spleen stiffness and prognosis following...BACKGROUND The impact of transjugular intrahepatic portosystemic shunt(TIPS)on liver and spleen stiffness remains unclear,as does the association between preoperative liver and spleen stiffness and prognosis following TIPS.AIM To investigate changes in liver and spleen stiffness after TIPS and examines the relationship between these parameters and the prognosis of post-TIPS patients.METHODS A total of 76 patients with liver cirrhosis and portal hypertension who underwent TIPS were included.Liver and spleen stiffness was assessed using the sound touch quantify(STQ)value,determined via point shear wave elastography in ultrasound imaging.Cox regression analysis was employed to evaluate the relationship between liver and spleen stiffness and cumulative survival in TIPS patients.RESULTS The liver STQ value demonstrated a marginally decreasing trend over time(P=0.052),while the spleen STQ value showed a significantly decreasing trend(P=0.025).Spleen STQ was positively correlated with portal pressure gradient(PPG)levels(rs=0.327,P=0.025).Cox regression analysis indicated that older age[hazard ratio(HR)=1.063,95%CI:0.997-1.133,P=0.060]and a higher liver STQ value(HR=1.051,95%CI:1.009-1.095,P=0.018)were associated with an increased mortality risk after TIPS.No significant correlation was found between liver or spleen stiffness and overt hepatic encephalopathy post-TIPS.The liver STQ value[area under the receiver operating characteristic curve(AUC)=0.724(95%CI:0.563-0.884)]showed superior predictive performance compared to the Child-Pugh score[AUC=0.699(95%CI:0.529-0.870)]and was comparable to the model for end-stage liver disease score[AUC=0.746(95%CI:0.591-0.902)].CONCLUSION Following TIPS,spleen stiffness exhibited a more pronounced change than liver stiffness and was positively associated with PPG.Preoperative liver stiffness serves as a prognostic indicator for survival in patients undergoing TIPS.展开更多
基金Project(51975169)supported by the National Natural Science Foundation of ChinaProject(LH2022E085)supported by the Natural Science Foundation of Heilongjiang Province,China。
文摘Efficient tool condition monitoring techniques help to realize intelligent management of tool life and reduce tool usage costs.In this paper,the influence of different wear degrees of ball-end milling cutters on the texture shape of machining tool marks is investigated,and a method is proposed for predicting the wear state(including the position and degree of tool wear)of ball-end milling cutters based on entropy measurement of tool mark texture images.Firstly,data samples are prepared through wear experiments,and the change law of the tool mark texture shape with the tool wear state is analyzed.Then,a two-dimensional sample entropy algorithm is developed to quantify the texture morphology.Finally,the processing parameters and tool attitude are integrated into the prediction process to predict the wear value and wear position of the ball end milling cutter.After testing,the correlation between the predicted value and the standard value of the proposed tool condition monitoring method reaches 95.32%,and the accuracy reaches 82.73%,indicating that the proposed method meets the requirement of tool condition monitoring.
基金Supported by National Natural Science Foundation of China,No.82200650Shanxi Provincial Clinical Research Center for Interventional Medicine,No.202204010501004+3 种基金the Precision Interventional Diagnosis and Treatment Technology Innovation Base for Cirrhosis and Portal Hypertension,No.YDZJSX20231B010the Natural Science Foundation of Shanxi Province,No.20210302124282 and No.202203021212046the Shanxi Province Higher Education“Billion Project Science and Technology Guidance Project”,No.2C622024120the National Natural Science Foundation of China Supporting Fund,No.Y82200650.
文摘BACKGROUND The impact of transjugular intrahepatic portosystemic shunt(TIPS)on liver and spleen stiffness remains unclear,as does the association between preoperative liver and spleen stiffness and prognosis following TIPS.AIM To investigate changes in liver and spleen stiffness after TIPS and examines the relationship between these parameters and the prognosis of post-TIPS patients.METHODS A total of 76 patients with liver cirrhosis and portal hypertension who underwent TIPS were included.Liver and spleen stiffness was assessed using the sound touch quantify(STQ)value,determined via point shear wave elastography in ultrasound imaging.Cox regression analysis was employed to evaluate the relationship between liver and spleen stiffness and cumulative survival in TIPS patients.RESULTS The liver STQ value demonstrated a marginally decreasing trend over time(P=0.052),while the spleen STQ value showed a significantly decreasing trend(P=0.025).Spleen STQ was positively correlated with portal pressure gradient(PPG)levels(rs=0.327,P=0.025).Cox regression analysis indicated that older age[hazard ratio(HR)=1.063,95%CI:0.997-1.133,P=0.060]and a higher liver STQ value(HR=1.051,95%CI:1.009-1.095,P=0.018)were associated with an increased mortality risk after TIPS.No significant correlation was found between liver or spleen stiffness and overt hepatic encephalopathy post-TIPS.The liver STQ value[area under the receiver operating characteristic curve(AUC)=0.724(95%CI:0.563-0.884)]showed superior predictive performance compared to the Child-Pugh score[AUC=0.699(95%CI:0.529-0.870)]and was comparable to the model for end-stage liver disease score[AUC=0.746(95%CI:0.591-0.902)].CONCLUSION Following TIPS,spleen stiffness exhibited a more pronounced change than liver stiffness and was positively associated with PPG.Preoperative liver stiffness serves as a prognostic indicator for survival in patients undergoing TIPS.
