Metadata are the information about and description of data.In Digital Earth,metadata become variant and heterogeneous with many uncertainties.This paper studies uncertain features in the generation and application of ...Metadata are the information about and description of data.In Digital Earth,metadata become variant and heterogeneous with many uncertainties.This paper studies uncertain features in the generation and application of metadata,and two types of uncertainties(incomplete and imprecise)are described based on semantic quantitative measurement method semantic relationship quantitative measurement based on possibilistic logic and probability statistic(SRQ-PP).Moreover,in the case study,we apply two types of quantitative measurements based on SRQ-PP to describe incomplete(uncertain)knowledge and imprecise(vague)information separately in spatial data service retrieval,which in turn is helpful to identify additional potential data resources and provide a quantitative analysis of the results.展开更多
Objective:Computed tomography pulmonary angiography(CTPA)parameters are valuable for predicting pulmonary hypertension(PH)in patients with pulmonary embolism(PE).However,few studies have used the coronary sinus ostium...Objective:Computed tomography pulmonary angiography(CTPA)parameters are valuable for predicting pulmonary hypertension(PH)in patients with pulmonary embolism(PE).However,few studies have used the coronary sinus ostium area(CSOA),derived from CTPA,to detect PH.This study aimed to compare the prognostic values of the CSOA,coronary sinus ostium diameter(CSOD),and right ventricular(RV)/left ventricular(LV)ratio for PH.Methods:This study retrospectively analyzed 78 patients(mean age,(51.94±12.33)years;53.8%male)with acute PE confirmed by CTPA at the Sixth and Eighth Medical Centers of the People’s Liberation Army General Hospital between June 2018 and June 2020.Patients were categorized into 2 groups using a pulmonary artery systolic pressure(PASP)cut-off of 30 mmHg.CTPA parameters were compared between these groups.Results:Patients with PASP>30 mmHg(n=22)had a larger CSOA,CSOD,RV diameter,RV/LV ratio,and inferior vena cava diameter compared with patients with PASP≤30 mmHg(n=56).The CSOA had an area under the receiver-operating characteristic curve(AUC,0.84;95%confidence interval(CI),0.74–0.94;P<0.001)similar to that of the RV/LV ratio(AUC,0.85;95%CI,0.73–0.99;P<0.001),while that of the CSOD was smaller(AUC,0.66;95%CI,0.51–0.81;P<0.05).Conclusion:Both CSOA and CSOD demonstrated a good ability to predict PH,while CSOA better predicted PASP>30 mmHg.展开更多
基金The work in this paper is supported by the National Natural Science Foundation of China under grant no.[61303130]the Natural Science Foundation of Hebei Province under grant no.[F2014203093].
文摘Metadata are the information about and description of data.In Digital Earth,metadata become variant and heterogeneous with many uncertainties.This paper studies uncertain features in the generation and application of metadata,and two types of uncertainties(incomplete and imprecise)are described based on semantic quantitative measurement method semantic relationship quantitative measurement based on possibilistic logic and probability statistic(SRQ-PP).Moreover,in the case study,we apply two types of quantitative measurements based on SRQ-PP to describe incomplete(uncertain)knowledge and imprecise(vague)information separately in spatial data service retrieval,which in turn is helpful to identify additional potential data resources and provide a quantitative analysis of the results.
基金supported by Beijing Municipal Science&Technology Commission(Z181100001718043).
文摘Objective:Computed tomography pulmonary angiography(CTPA)parameters are valuable for predicting pulmonary hypertension(PH)in patients with pulmonary embolism(PE).However,few studies have used the coronary sinus ostium area(CSOA),derived from CTPA,to detect PH.This study aimed to compare the prognostic values of the CSOA,coronary sinus ostium diameter(CSOD),and right ventricular(RV)/left ventricular(LV)ratio for PH.Methods:This study retrospectively analyzed 78 patients(mean age,(51.94±12.33)years;53.8%male)with acute PE confirmed by CTPA at the Sixth and Eighth Medical Centers of the People’s Liberation Army General Hospital between June 2018 and June 2020.Patients were categorized into 2 groups using a pulmonary artery systolic pressure(PASP)cut-off of 30 mmHg.CTPA parameters were compared between these groups.Results:Patients with PASP>30 mmHg(n=22)had a larger CSOA,CSOD,RV diameter,RV/LV ratio,and inferior vena cava diameter compared with patients with PASP≤30 mmHg(n=56).The CSOA had an area under the receiver-operating characteristic curve(AUC,0.84;95%confidence interval(CI),0.74–0.94;P<0.001)similar to that of the RV/LV ratio(AUC,0.85;95%CI,0.73–0.99;P<0.001),while that of the CSOD was smaller(AUC,0.66;95%CI,0.51–0.81;P<0.05).Conclusion:Both CSOA and CSOD demonstrated a good ability to predict PH,while CSOA better predicted PASP>30 mmHg.
