There are many factors,that affect the development of indoor fire,such as the size of the fire source,the opening or space of the room,and the nature of the combustible materials.Among them,the space of the room,has a...There are many factors,that affect the development of indoor fire,such as the size of the fire source,the opening or space of the room,and the nature of the combustible materials.Among them,the space of the room,has a significant impact on the development of a ventilation-limited fire.In this paper,the Fire Dynamics Simulator(FDS)software is used to analyze,the risk of fire initiation in the restricted ventilated compartment,when the size of vertical ventilation space is different.Through,a combination of experimental design,numerical simulation,and theoretical analysis,the changes in the level of carbon monoxide,visibility,temperature,Heat Release Rate(HRR)and,the smoke exhaust efficiency of natural smoke at different opening sizes are observed.It is observed that,when the ratio of inlet and outlet area reaches 2:1,the natural smoke exhaust effect is the best,however,the increasing in the opening size has little significance on the smoke exhaust effect.The research on the influence of smoke outlet size,will helps in the development of the law regarding fire prevention,smoke exhaust design,and fire rescue work of a building.展开更多
To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,00...To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,000,probably due to a rising trend of obesity and gallstone disease.AP is associated with remarkable pain,reduced quality of life(QoL),and even death,thus posing a heavy socioeconomic burden.In addition,approximately 22%of AP patients experience recurrent AP(RAP)and 10%of AP patients progress to chronic pancreatitis.[2]Petrov and Yadav[3]have,therefore,argued that AP should not be considered as an acute and self-limiting disease.Treatment and long-term care after AP have drawn widespread attention,which has improved patients’physical and mental health.展开更多
文摘There are many factors,that affect the development of indoor fire,such as the size of the fire source,the opening or space of the room,and the nature of the combustible materials.Among them,the space of the room,has a significant impact on the development of a ventilation-limited fire.In this paper,the Fire Dynamics Simulator(FDS)software is used to analyze,the risk of fire initiation in the restricted ventilated compartment,when the size of vertical ventilation space is different.Through,a combination of experimental design,numerical simulation,and theoretical analysis,the changes in the level of carbon monoxide,visibility,temperature,Heat Release Rate(HRR)and,the smoke exhaust efficiency of natural smoke at different opening sizes are observed.It is observed that,when the ratio of inlet and outlet area reaches 2:1,the natural smoke exhaust effect is the best,however,the increasing in the opening size has little significance on the smoke exhaust effect.The research on the influence of smoke outlet size,will helps in the development of the law regarding fire prevention,smoke exhaust design,and fire rescue work of a building.
基金funded by grants from National Natural Science Foundation of China(No.32170788)National Clinical Key Specialty Construction Project(No.ZK108000)+1 种基金National High Level Hospital Clinical Research Funding(No.2022-PUMCH-B-023)Beijing Natural Science Foundation(No.7232123)
文摘To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,000,probably due to a rising trend of obesity and gallstone disease.AP is associated with remarkable pain,reduced quality of life(QoL),and even death,thus posing a heavy socioeconomic burden.In addition,approximately 22%of AP patients experience recurrent AP(RAP)and 10%of AP patients progress to chronic pancreatitis.[2]Petrov and Yadav[3]have,therefore,argued that AP should not be considered as an acute and self-limiting disease.Treatment and long-term care after AP have drawn widespread attention,which has improved patients’physical and mental health.