In order to improve the accuracy of target intent recognition,a recognition method based on XGBoost(eXtreme Gradient Boosting)decision tree is proposed.This paper adopts relevant data and program of python to calculat...In order to improve the accuracy of target intent recognition,a recognition method based on XGBoost(eXtreme Gradient Boosting)decision tree is proposed.This paper adopts relevant data and program of python to calculate the probability of tactical intention.Then the sequence intention probability is obtained by applying Dempster-Shafer rule of combination.To verify the accuracy of recognition results,we compare the experimental results of this paper with the results in the literatures.The experiment shows that the probability of tactical intention recognition through this method is improved,so this method is feasible.展开更多
Mesh-free finite difference(FD)methods can improve the geometric flexibility of modeling without the need for lattice mapping or complex meshing process.Radial-basisfunction-generated FD is among the most commonly use...Mesh-free finite difference(FD)methods can improve the geometric flexibility of modeling without the need for lattice mapping or complex meshing process.Radial-basisfunction-generated FD is among the most commonly used mesh-free FD methods and can accurately simulate seismic wave propagation in the non-rectangular computational domain.In this paper,we propose a perfectly matched layer(PML)boundary condition for a meshfree FD solution of the elastic wave equation,which can be applied to the boundaries of the non-rectangular velocity model.The performance of the PML is,however,severely reduced for near-grazing incident waves and low-frequency waves.We thus also propose the complexfrequency-shifted PML(CFS-PML)boundary condition for a mesh-free FD solution of the elastic wave equation.For two PML boundary conditions,we derive unsplit time-domain expressions by constructing auxiliary differential equations,both of which require less memory and are easy for programming.Numerical experiments demonstrate that these two PML boundary conditions effectively eliminate artificial boundary reflections in mesh-free FD simulations.When compared with the PML boundary condition,the CFS-PML boundary condition results in better absorption for near-grazing incident waves and evanescent waves.展开更多
Background The relationship between inflammation and delirium remains to be determined.The purposes of this study were to investigate the association between serum interleukin-6 levels and the occurrence of delirium i...Background The relationship between inflammation and delirium remains to be determined.The purposes of this study were to investigate the association between serum interleukin-6 levels and the occurrence of delirium in elderly patients after major noncardiac surgery.Methods A total of 338 elderly patients （60 years of age and over） undergoing major noncardiac surgery were enrolled.Blood samples were obtained before anesthesia and in the first postoperative morning and serum interleukin-6 concentrations were measured.Delirium was assessed twice daily by the confusion assessment method for the Intensive Care Unit during the first three postoperative days.Survival analyses were performed to assess the relationship between the serum IL-6 level and the occurrence of postoperative delirium.Results Postoperative delirium occurred in 14.8% （50 of 338） of patients.High serum interleukin-6 levelsafter surgery were significantly associated with increased risk of the occurrence of postoperative delirium （hazard ratio 1.514,95% confidence interval 1.155-1.985,P=0.003）.Other independent predictors of delirium included increasing age,poor preoperative New York Heart Association classification,low preoperative Mini-Mental State Examination score,and high total postoperative Visual Analogue Scale pain score.Patients who developed delirium had a prolonged hospital stay after surgery.Conclusions Delirium is a frequent complication in elderly patients after noncardiac surgery.High serum interleukin-6 level after surgery is associated with increased risk of the occurrence of postoperative delirium.展开更多
Background Studies on postoperative cognitive dysfunction （POCD） have attracted extensive attention and achieved significant progress. However, the diagnosis of POCD is not very satisfactory as no specific biomarker...Background Studies on postoperative cognitive dysfunction （POCD） have attracted extensive attention and achieved significant progress. However, the diagnosis of POCD is not very satisfactory as no specific biomarkers have been classified. The aim of the present study was to evaluate differences in serum protein composition between POCD and Non-POCD patients, identify potential biomarkers associated with early POCD, and study the mechanism underlying POCD. Methods Sixty-eight elderly patients （age 〉65 years） received isoflurane inhalation anesthesia for arthroplasty surgeries. One day before and seven days after the surgery, these patients were subjected to a neuropsychological test and venous blood sample collection. Postoperative cognitive dysfunction was determined using Z test scores. Based on the results, the patients were divided into POCD and non-POCD groups. Twenty-five randomly chosen blood samples obtained seven days after the surgery from each group were analyzed on a Bruker ultraFlexTM time of flight （TOF）/TOF mass spectrophotometer. The resulting peptide fingerprints were compared with those from the pre-surgery samples to identify differences in serum protein composition. The model designed to distinguish between a non-POCD group and a POCD group were established and validated. Three proteins with the most significant changes were selected for further characterization. Results Thirty-three cases were diagnosed as POCD. Using the Clinprotools software, 58 polypeptides were found to display differential expression （P 〈0.05）. Using a support vector algorithm method, seven differential peaks were isolated to establish a diagnostic model to distinguish POCD patients from normal individuals. The prediction rate and recognition rate were 96.89% and 100%, respectively. Validation of this model showed that the accuracy rates were 100% and 85% using samples from the POCD and non-POCD groups, respectively. Protein analysis also led to the identification of fibrinopeptide A （FPA） as a potential biomarker for POCD. Conclusions Arthroplastic surgery under isoflurane inhalation anesthesia causes differential serum protein expression in elderly patients. These differentially expressed proteins may contribute to the diagnosis of early POCD, which may provide a basis for identifying the underlying mechanism of POCD development.展开更多
文摘In order to improve the accuracy of target intent recognition,a recognition method based on XGBoost(eXtreme Gradient Boosting)decision tree is proposed.This paper adopts relevant data and program of python to calculate the probability of tactical intention.Then the sequence intention probability is obtained by applying Dempster-Shafer rule of combination.To verify the accuracy of recognition results,we compare the experimental results of this paper with the results in the literatures.The experiment shows that the probability of tactical intention recognition through this method is improved,so this method is feasible.
基金supported by the National Science and Technology Major Project(2016ZX05006-002)the National Natural Science Foundation of China(Nos.41874153,41504097)
文摘Mesh-free finite difference(FD)methods can improve the geometric flexibility of modeling without the need for lattice mapping or complex meshing process.Radial-basisfunction-generated FD is among the most commonly used mesh-free FD methods and can accurately simulate seismic wave propagation in the non-rectangular computational domain.In this paper,we propose a perfectly matched layer(PML)boundary condition for a meshfree FD solution of the elastic wave equation,which can be applied to the boundaries of the non-rectangular velocity model.The performance of the PML is,however,severely reduced for near-grazing incident waves and low-frequency waves.We thus also propose the complexfrequency-shifted PML(CFS-PML)boundary condition for a mesh-free FD solution of the elastic wave equation.For two PML boundary conditions,we derive unsplit time-domain expressions by constructing auxiliary differential equations,both of which require less memory and are easy for programming.Numerical experiments demonstrate that these two PML boundary conditions effectively eliminate artificial boundary reflections in mesh-free FD simulations.When compared with the PML boundary condition,the CFS-PML boundary condition results in better absorption for near-grazing incident waves and evanescent waves.
文摘Background The relationship between inflammation and delirium remains to be determined.The purposes of this study were to investigate the association between serum interleukin-6 levels and the occurrence of delirium in elderly patients after major noncardiac surgery.Methods A total of 338 elderly patients （60 years of age and over） undergoing major noncardiac surgery were enrolled.Blood samples were obtained before anesthesia and in the first postoperative morning and serum interleukin-6 concentrations were measured.Delirium was assessed twice daily by the confusion assessment method for the Intensive Care Unit during the first three postoperative days.Survival analyses were performed to assess the relationship between the serum IL-6 level and the occurrence of postoperative delirium.Results Postoperative delirium occurred in 14.8% （50 of 338） of patients.High serum interleukin-6 levelsafter surgery were significantly associated with increased risk of the occurrence of postoperative delirium （hazard ratio 1.514,95% confidence interval 1.155-1.985,P=0.003）.Other independent predictors of delirium included increasing age,poor preoperative New York Heart Association classification,low preoperative Mini-Mental State Examination score,and high total postoperative Visual Analogue Scale pain score.Patients who developed delirium had a prolonged hospital stay after surgery.Conclusions Delirium is a frequent complication in elderly patients after noncardiac surgery.High serum interleukin-6 level after surgery is associated with increased risk of the occurrence of postoperative delirium.
基金This work was supported by a grant from the Natural Science Foundation of Beijing （No. 7062026）.
文摘Background Studies on postoperative cognitive dysfunction （POCD） have attracted extensive attention and achieved significant progress. However, the diagnosis of POCD is not very satisfactory as no specific biomarkers have been classified. The aim of the present study was to evaluate differences in serum protein composition between POCD and Non-POCD patients, identify potential biomarkers associated with early POCD, and study the mechanism underlying POCD. Methods Sixty-eight elderly patients （age 〉65 years） received isoflurane inhalation anesthesia for arthroplasty surgeries. One day before and seven days after the surgery, these patients were subjected to a neuropsychological test and venous blood sample collection. Postoperative cognitive dysfunction was determined using Z test scores. Based on the results, the patients were divided into POCD and non-POCD groups. Twenty-five randomly chosen blood samples obtained seven days after the surgery from each group were analyzed on a Bruker ultraFlexTM time of flight （TOF）/TOF mass spectrophotometer. The resulting peptide fingerprints were compared with those from the pre-surgery samples to identify differences in serum protein composition. The model designed to distinguish between a non-POCD group and a POCD group were established and validated. Three proteins with the most significant changes were selected for further characterization. Results Thirty-three cases were diagnosed as POCD. Using the Clinprotools software, 58 polypeptides were found to display differential expression （P 〈0.05）. Using a support vector algorithm method, seven differential peaks were isolated to establish a diagnostic model to distinguish POCD patients from normal individuals. The prediction rate and recognition rate were 96.89% and 100%, respectively. Validation of this model showed that the accuracy rates were 100% and 85% using samples from the POCD and non-POCD groups, respectively. Protein analysis also led to the identification of fibrinopeptide A （FPA） as a potential biomarker for POCD. Conclusions Arthroplastic surgery under isoflurane inhalation anesthesia causes differential serum protein expression in elderly patients. These differentially expressed proteins may contribute to the diagnosis of early POCD, which may provide a basis for identifying the underlying mechanism of POCD development.
