The mining area deformation monitoring theory and method using precise point positioning （PPP） ambi- guity resolution （AR） were studied, and an ambiguity fixing model with satellite and receiver combina- tion phas...The mining area deformation monitoring theory and method using precise point positioning （PPP） ambi- guity resolution （AR） were studied, and an ambiguity fixing model with satellite and receiver combina- tion phase delay （CPD） was proposed for zero-differenced PPP ambiguity fixing and its corresponding formula derivation was given. The data processing results for I h at six IGS stations in China show that 93% of ambiguities can be fixed within 10 min and all ambiguities can be fixed within 15 min. After ambi- guity fixing, the positioning accuracy is improved by more than 85% in the E and N directions, with abso- lute positioning accuracy reaching millimeter level, and it was improved by 70% in the U direction, reaching centimeter level; the proposed zero-differenced ambiguity fixing model can effectively improve the convergence rate and positioning accuracy in PPP. Data monitoring continuously conducted for half a year at four COPS stations of Shanxi China Coal Pingshuo Group validated the feasibility of using PPP in mining area deformation monitoring.展开更多
The precision of deformation monitoring with Global Navigation Satellite System(GNSS)relative positioning is significantly influenced by the distance between the monitoring and base stations.In long strip regions,the ...The precision of deformation monitoring with Global Navigation Satellite System(GNSS)relative positioning is significantly influenced by the distance between the monitoring and base stations.In long strip regions,the considerable differences in station spacing lead to inconsistent monitoring precision among multiple stations.This presents a challenge to accurately model and predict the deformation pattern.To tackle this issue,this paper introduces a novel dual-base station constraint method.This method integrates the baseline length constraint between two base stations into the conventional relative positioning model.The formulae of the proposed method are first derived in detail.Then the data collected at eight monitoring stations in two strip regions of 6 km and 8 km over a 28-day period are used to validate the effectiveness of the proposed method.The quantitative analysis of monitoring precision consistency indicators and hypothesis testing on the correlation between monitoring precision and station spacing are conducted.The results show that:(1)median values of the East,North,and Up consistency indicators are reduced from 2.14,1.41,and 1.83 to 0.91,0.67,and 0.55 and from 1.85,1.85,and 2.32 to 0.69,1.00,and 0.87,respectively,indicating monitoring precision consistency improvement for two case studies;(2)the absolute values of the correlation coefficients between monitoring precision and station spacing decrease from 0.99,0.94,and 0.98 to 0.09,0.36,and 0.32.Using the t-test with a significant level of 0.01,it is demonstrated that there is no significant correlation between monitoring precision and station spacing when employing the proposed method.展开更多
Precise drought monitoring is necessary for refined assessment of drought disasters.Usually,the meteorological drought composite index(MCI)is calculated based on long time series data over 30 years so as to fit stable...Precise drought monitoring is necessary for refined assessment of drought disasters.Usually,the meteorological drought composite index(MCI)is calculated based on long time series data over 30 years so as to fit stable probability distribution of precipitation.In order to fully utilize short-term high-density station data that are usually less than20 years for drought monitoring,a parameter method is introduced in this study.The parameter method is to calculate the parameters of the probability distribution function of precipitation using data from neighboring long-term stations,and then interpolate them to that of short-term stations,so that MCI of short-term stations can be calculated.In this study,31 national stations in 9 provinces/regions were selected for cross-checking and analysis of the errors of MCI calculated from the parameter method,as well as the interpolation method and the replacement method.The results show that except in the areas of Northwest China where meteorological stations are comparatively sparse,the MCI calculated by the parameter method is significantly better than that from the other two methods.Compared with the interpolation method,the accuracy of MCI calculated by the parameter method is improved in the central and eastern China,with improved accuracy by over 20%in most parts of North China,Northeast China,Yangtze River basin,Southwest China,and South China.The magnitude of error caused by the parameter method is close to or smaller than that caused by climate change,representing a good stability of the method.During the serious drought in the Yangtze River basin in 2022,comparison of the MCI results from 86 long-term stations and 2688 short-term high-density stations in Jiangxi Province shows that the parameter method used for calculating MCI of short-term stations can create high-resolution map for drought monitoring and provide refined services for drought disaster reduction.展开更多
Inflammatory bowel disease(IBD)is an incurable disease characterized by remission-relapse cycles throughout its course.Both Crohn's disease(CD)and ulcerative colitis(UC),the two main forms of IBD,exhibit tendency ...Inflammatory bowel disease(IBD)is an incurable disease characterized by remission-relapse cycles throughout its course.Both Crohn's disease(CD)and ulcerative colitis(UC),the two main forms of IBD,exhibit tendency to develop complications and substantial heterogeneity in terms of frequency and severity of relapse,thus posing great challenges to the clinical management for IBD.Current treatment strategies are effective in different ways in induction and maintenance therapies for IBD.Recent advances in studies of genetics,pharmacogenetics,proteomics and microbiome provide a strong driving force for identifying molecular markers of prognosis and treatment response,which should help clinicians manage IBD patients more effectively,and then,improve clinical outcomes and reduce treatment costs of patients.In this review,we summarize and discuss precision medicine in IBD,focusing on predictive markers of disease course and treatment response,and monitoring indices during therapeutic drug monitoring.展开更多
基金Financial support from the National Natural Science Foundation of China (No. 41074010)the Jiangsu Innovation Works Fund of Postgraduate (No. CXZZ11-0299)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘The mining area deformation monitoring theory and method using precise point positioning （PPP） ambi- guity resolution （AR） were studied, and an ambiguity fixing model with satellite and receiver combina- tion phase delay （CPD） was proposed for zero-differenced PPP ambiguity fixing and its corresponding formula derivation was given. The data processing results for I h at six IGS stations in China show that 93% of ambiguities can be fixed within 10 min and all ambiguities can be fixed within 15 min. After ambi- guity fixing, the positioning accuracy is improved by more than 85% in the E and N directions, with abso- lute positioning accuracy reaching millimeter level, and it was improved by 70% in the U direction, reaching centimeter level; the proposed zero-differenced ambiguity fixing model can effectively improve the convergence rate and positioning accuracy in PPP. Data monitoring continuously conducted for half a year at four COPS stations of Shanxi China Coal Pingshuo Group validated the feasibility of using PPP in mining area deformation monitoring.
基金supported by the National Natural Science Foundation of China (Grant No.42274050).
文摘The precision of deformation monitoring with Global Navigation Satellite System(GNSS)relative positioning is significantly influenced by the distance between the monitoring and base stations.In long strip regions,the considerable differences in station spacing lead to inconsistent monitoring precision among multiple stations.This presents a challenge to accurately model and predict the deformation pattern.To tackle this issue,this paper introduces a novel dual-base station constraint method.This method integrates the baseline length constraint between two base stations into the conventional relative positioning model.The formulae of the proposed method are first derived in detail.Then the data collected at eight monitoring stations in two strip regions of 6 km and 8 km over a 28-day period are used to validate the effectiveness of the proposed method.The quantitative analysis of monitoring precision consistency indicators and hypothesis testing on the correlation between monitoring precision and station spacing are conducted.The results show that:(1)median values of the East,North,and Up consistency indicators are reduced from 2.14,1.41,and 1.83 to 0.91,0.67,and 0.55 and from 1.85,1.85,and 2.32 to 0.69,1.00,and 0.87,respectively,indicating monitoring precision consistency improvement for two case studies;(2)the absolute values of the correlation coefficients between monitoring precision and station spacing decrease from 0.99,0.94,and 0.98 to 0.09,0.36,and 0.32.Using the t-test with a significant level of 0.01,it is demonstrated that there is no significant correlation between monitoring precision and station spacing when employing the proposed method.
基金Supported by the National Key Research and Development Program of China(2023YFC3206001,2023YFC3006601,and 2017YFC1502402)Local Operational Construction Project of Hebei Province:Improving Capability of Meteorological Drought Monitoring,Evaluation,and Prediction(22302002)。
文摘Precise drought monitoring is necessary for refined assessment of drought disasters.Usually,the meteorological drought composite index(MCI)is calculated based on long time series data over 30 years so as to fit stable probability distribution of precipitation.In order to fully utilize short-term high-density station data that are usually less than20 years for drought monitoring,a parameter method is introduced in this study.The parameter method is to calculate the parameters of the probability distribution function of precipitation using data from neighboring long-term stations,and then interpolate them to that of short-term stations,so that MCI of short-term stations can be calculated.In this study,31 national stations in 9 provinces/regions were selected for cross-checking and analysis of the errors of MCI calculated from the parameter method,as well as the interpolation method and the replacement method.The results show that except in the areas of Northwest China where meteorological stations are comparatively sparse,the MCI calculated by the parameter method is significantly better than that from the other two methods.Compared with the interpolation method,the accuracy of MCI calculated by the parameter method is improved in the central and eastern China,with improved accuracy by over 20%in most parts of North China,Northeast China,Yangtze River basin,Southwest China,and South China.The magnitude of error caused by the parameter method is close to or smaller than that caused by climate change,representing a good stability of the method.During the serious drought in the Yangtze River basin in 2022,comparison of the MCI results from 86 long-term stations and 2688 short-term high-density stations in Jiangxi Province shows that the parameter method used for calculating MCI of short-term stations can create high-resolution map for drought monitoring and provide refined services for drought disaster reduction.
基金supported in part by the Sichuan International Science and Technology Innovation Cooperation/Hong Kong/Macao/Taiwan Science and Technology Innovation Cooperation Project (Grant No.2021YFH0189)the Sichuan International Science Foundation Project (Grant No.2022NSFSC1363)the project for disciplines of excellence-Clinical Research Incubation Project,West China Hospital,Sichuan University (Grant No.2021HXFH065).
文摘Inflammatory bowel disease(IBD)is an incurable disease characterized by remission-relapse cycles throughout its course.Both Crohn's disease(CD)and ulcerative colitis(UC),the two main forms of IBD,exhibit tendency to develop complications and substantial heterogeneity in terms of frequency and severity of relapse,thus posing great challenges to the clinical management for IBD.Current treatment strategies are effective in different ways in induction and maintenance therapies for IBD.Recent advances in studies of genetics,pharmacogenetics,proteomics and microbiome provide a strong driving force for identifying molecular markers of prognosis and treatment response,which should help clinicians manage IBD patients more effectively,and then,improve clinical outcomes and reduce treatment costs of patients.In this review,we summarize and discuss precision medicine in IBD,focusing on predictive markers of disease course and treatment response,and monitoring indices during therapeutic drug monitoring.
