Rural-to-urban migration and globalized trade are swelling cities worldwide,but these forces are perhaps more powerfully concentrated in Dhaka,Bangladesh,than anywhere on earth.Born of a natural disaster 50 years ago,...Rural-to-urban migration and globalized trade are swelling cities worldwide,but these forces are perhaps more powerfully concentrated in Dhaka,Bangladesh,than anywhere on earth.Born of a natural disaster 50 years ago,the world’s most densely-populated country faces multiple environmental challenges.Water,with seasonal monsoons,is both a blessing and a curse.A one meter rise in sea level,for example,would displace as many as 25 million Bangladeshis,and cause the largest mass migration in history.Each drought,flood,or cyclone drives scores of environmental refugees from rural areas to the capital city of Dhaka,where air and water pollution run rampant.Recent rapprochement with India over decades-long boundary disputes offers hope that environmental cooperation in the vulnerable Bay of Bengal can follow.展开更多
The human factors and their interaction with other factors play an important role in the flight safety of transport aircraft.In this paper,a paradigm of risk assessment for transport aircraft interacting with piloting...The human factors and their interaction with other factors play an important role in the flight safety of transport aircraft.In this paper,a paradigm of risk assessment for transport aircraft interacting with piloting behaviors is proposed,with focus on landing which is the most accident-prone flight stage in aviation safety statistics.Model-based flight simulation serves as our data source for landing risk analysis under uncertainties.A digital pilot in the loop that reflects the human piloting behaviors is employed to facilitate simulation efficiency.Eight types of unsafe events in landing are identified from statistics.On this basis,the landing safety boundary is extracted via stochastic simulation to divide safety and hazardous flight status domains,which con-tributes to flight status management and risk warning.The simulation results indicate that appro-priate piloting behavior,which is active response and fast target acquisition with minimum overshoot and fluctuation,shows benefit to landing safety.The subset simulation technique is employed to further refine the boundary with less computational workload.Furthermore,the effect of airspeed,windspeed,and other factors on landing risk is also discussed.The proposed risk assess-ment method would help optimize operation procedure and develop targeted pilot training program.展开更多
文摘Rural-to-urban migration and globalized trade are swelling cities worldwide,but these forces are perhaps more powerfully concentrated in Dhaka,Bangladesh,than anywhere on earth.Born of a natural disaster 50 years ago,the world’s most densely-populated country faces multiple environmental challenges.Water,with seasonal monsoons,is both a blessing and a curse.A one meter rise in sea level,for example,would displace as many as 25 million Bangladeshis,and cause the largest mass migration in history.Each drought,flood,or cyclone drives scores of environmental refugees from rural areas to the capital city of Dhaka,where air and water pollution run rampant.Recent rapprochement with India over decades-long boundary disputes offers hope that environmental cooperation in the vulnerable Bay of Bengal can follow.
基金supported by the Airworthiness Technology Research Center of Beihang University,China.
文摘The human factors and their interaction with other factors play an important role in the flight safety of transport aircraft.In this paper,a paradigm of risk assessment for transport aircraft interacting with piloting behaviors is proposed,with focus on landing which is the most accident-prone flight stage in aviation safety statistics.Model-based flight simulation serves as our data source for landing risk analysis under uncertainties.A digital pilot in the loop that reflects the human piloting behaviors is employed to facilitate simulation efficiency.Eight types of unsafe events in landing are identified from statistics.On this basis,the landing safety boundary is extracted via stochastic simulation to divide safety and hazardous flight status domains,which con-tributes to flight status management and risk warning.The simulation results indicate that appro-priate piloting behavior,which is active response and fast target acquisition with minimum overshoot and fluctuation,shows benefit to landing safety.The subset simulation technique is employed to further refine the boundary with less computational workload.Furthermore,the effect of airspeed,windspeed,and other factors on landing risk is also discussed.The proposed risk assess-ment method would help optimize operation procedure and develop targeted pilot training program.
