Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are ...Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control.Methods:As a theater centers for disease prevention and control,we established an influenza monitoring platform(IMP)in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection.In this study,we introduced the constitution,influenza virus detection,and quality control for an IMP.The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems.The experiences and problems associated with the platform also were summarized.Results:A theater IMP was established based on 3 levels of medical units,including monitoring sites,testing laboratories and a checking laboratory.A series of measures were taken to guarantee the quality of monitoring,such as technical training,a unified process,sufficient supervision and timely communication.The platform has run smoothly for 3 monitoring years to date.In the 2014–2015 and 2016–2017 monitoring years,sample amount coincided with that obtained from the National Influenza Surveillance program.In the 2015–2016 monitoring year,due to the strict prevention and control measures,an influenza epidemic peak was avoided in monitoring units,and the monitoring data did not coincide with that of the National Influenza Surveillance program.Several problems,including insufficient attention,unreasonable administrative intervention or subordination relationships,and the necessity of detection in monitoring sites were still observed.Conclusion:A theater IMP was established rationally and played a deserved role in the prevention and control of influenza.However,several problems remain to be solved.展开更多
Reliability evaluation for aircraft engines is difficult because of the scarcity of failure data. But aircraft engine data are available from a variety of sources. Data fusion has the function of maximizing the amount...Reliability evaluation for aircraft engines is difficult because of the scarcity of failure data. But aircraft engine data are available from a variety of sources. Data fusion has the function of maximizing the amount of valu- able information extracted from disparate data sources to obtain the comprehensive reliability knowledge. Consid- ering the degradation failure and the catastrophic failure simultaneously, which are competing risks and can affect the reliability, a reliability evaluation model based on data fusion for aircraft engines is developed, Above the characteristics of the proposed model, reliability evaluation is more feasible than that by only utilizing failure data alone, and is also more accurate than that by only considering single failure mode. Example shows the effective- ness of the proposed model.展开更多
Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straig...Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straight or obliquely inserted concrete plates(SIP or OIP),significantly influence the efficiency of sand-control.This study performs a comparative evaluation of the SIP and OIP sand-control fences using wind tunnel testing and field monitoring data collected from the Lanzhou–Wulumuqi High-Speed Railway Project.The results show that the fence’s ability to reduce the wind speed and the sand-retaining efficiency gradually weakens with the increasing wind speed.Compared with the SIP fence,the OIP fence has a better wind speed reduction capability,stronger ability to capture fine particles below the top of the fence;it is more efficient for sand-retaining and induces stronger eddy intensity.Generally,the wind tunnel test and field monitoring results are consistent,whereas wind tunnel tests incline to overestimate wind speed reduction and sand-control efficiency.The study also finds that the aeolian sand accumulated around the fence can weaken the protection efficiency,and hence cleaning the aeolian sand accumulated around the fence should be done periodically to ensure the designed functions.展开更多
文摘Background:Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army,which directly disturbs military training and affects soldiers’health.Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control.Methods:As a theater centers for disease prevention and control,we established an influenza monitoring platform(IMP)in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection.In this study,we introduced the constitution,influenza virus detection,and quality control for an IMP.The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems.The experiences and problems associated with the platform also were summarized.Results:A theater IMP was established based on 3 levels of medical units,including monitoring sites,testing laboratories and a checking laboratory.A series of measures were taken to guarantee the quality of monitoring,such as technical training,a unified process,sufficient supervision and timely communication.The platform has run smoothly for 3 monitoring years to date.In the 2014–2015 and 2016–2017 monitoring years,sample amount coincided with that obtained from the National Influenza Surveillance program.In the 2015–2016 monitoring year,due to the strict prevention and control measures,an influenza epidemic peak was avoided in monitoring units,and the monitoring data did not coincide with that of the National Influenza Surveillance program.Several problems,including insufficient attention,unreasonable administrative intervention or subordination relationships,and the necessity of detection in monitoring sites were still observed.Conclusion:A theater IMP was established rationally and played a deserved role in the prevention and control of influenza.However,several problems remain to be solved.
基金Supported by the National Natural Science Foundation of China and Aviation Fund(60879001)the Natural Science Foundation of Jiangsu Province(BK2009378)+1 种基金the Fundamental Research Fund of Nanjing University of Aeronautics and Astronautics(NS2010179)the Qinglan Project of Jiangsu Province~~
文摘Reliability evaluation for aircraft engines is difficult because of the scarcity of failure data. But aircraft engine data are available from a variety of sources. Data fusion has the function of maximizing the amount of valu- able information extracted from disparate data sources to obtain the comprehensive reliability knowledge. Consid- ering the degradation failure and the catastrophic failure simultaneously, which are competing risks and can affect the reliability, a reliability evaluation model based on data fusion for aircraft engines is developed, Above the characteristics of the proposed model, reliability evaluation is more feasible than that by only utilizing failure data alone, and is also more accurate than that by only considering single failure mode. Example shows the effective- ness of the proposed model.
基金This research was supported by the Science and Technology Development Plan of China Railway Group Limited(Grant No.2015-kj035-g004-03).
文摘Concrete-plate fences have been widely adopted for windblown sand control and mitigation along railways.However,the inclination angles of inserting the concrete plate with respect to the vertical direction,i.e.,straight or obliquely inserted concrete plates(SIP or OIP),significantly influence the efficiency of sand-control.This study performs a comparative evaluation of the SIP and OIP sand-control fences using wind tunnel testing and field monitoring data collected from the Lanzhou–Wulumuqi High-Speed Railway Project.The results show that the fence’s ability to reduce the wind speed and the sand-retaining efficiency gradually weakens with the increasing wind speed.Compared with the SIP fence,the OIP fence has a better wind speed reduction capability,stronger ability to capture fine particles below the top of the fence;it is more efficient for sand-retaining and induces stronger eddy intensity.Generally,the wind tunnel test and field monitoring results are consistent,whereas wind tunnel tests incline to overestimate wind speed reduction and sand-control efficiency.The study also finds that the aeolian sand accumulated around the fence can weaken the protection efficiency,and hence cleaning the aeolian sand accumulated around the fence should be done periodically to ensure the designed functions.
