The Wenchuan earthquake is a natural disaster. Its occurrence and aftermath have demonstrated the critical roles of seismology and earthquake engineering in reducing seismic hazards and damages. However,their existing...The Wenchuan earthquake is a natural disaster. Its occurrence and aftermath have demonstrated the critical roles of seismology and earthquake engineering in reducing seismic hazards and damages. However,their existing limitations should also be underscored. This article summarized and reviewed the current scientific understanding of earthquake ruptures, and new insights gained since the Wenchuan event. This study focused on the related challenges to seismology and earthquake engineering as follows:(1) The under-estimation of earthquake risks before occurrences.(2) The current limited data regarding large earthquakes in continental thrust fault systems.(3) The causal relationship between the Wenchuan earthquake and the reservoir impoundment in its vicinity.(4) The identification of low-velocity zone in the crust and its seismogenical role.(5) The casualties and economic losses from a cascade of diverse natural hazards triggered by the ruptures, and the excellent earthquake resistance associated with tunnels in mountainous terrain.展开更多
In recent years,natural disasters in coastal areas have become more frequent due to sea level rise and other impact factors under the scenario of global warming,causing great losses to human society.Mangrove forest,an...In recent years,natural disasters in coastal areas have become more frequent due to sea level rise and other impact factors under the scenario of global warming,causing great losses to human society.Mangrove forest,an important shelterbelt in coastal areas,plays an extremely important role in reducing the coastal hazards risk.In this paper,the effects of mangrove ecosystem on coastal hazards reduction are reviewed from the aspects of wind prevention,wave attenuation,sedimentation acceleration,tsunamis mitigation,and provide theoretical support and technical guidance for the protection and cultivation of mangrove forests.展开更多
This paper considers and describes the cool burning techniques long utilized by Australian Indigenous people as a contributor to bushfire mitigation. Indigenous fire management involves lighting the </span></...This paper considers and describes the cool burning techniques long utilized by Australian Indigenous people as a contributor to bushfire mitigation. Indigenous fire management involves lighting the </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">“</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">cool</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">”</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> fires in selected areas between March and July, in Australia, during the early dry season. The fires burn gradually, reducing fuel loads and creating fire breaks and not all of the area</span><span style="font-family:Verdana;"> is burnt. Late in the dry season, when the weather is</span><span style="font-family:Verdana;"> very hot, the method </span><span style="font-family:Verdana;">removes fuel for larger fires while maintaining and protecting habitat for mammals</span><span style="font-family:Verdana;">, reptiles, insects and birds. The management of Indigenous cultural fire offers an Indigenous viewpoint for wider control of fire and cultural fire </span><span style="font-family:Verdana;">management is an opportunity for collaborations to encourage Aboriginal empo</span><span style="font-family:Verdana;">werment with public and private sector organisations. Effective cool burning in contemporary prescribed burning activities can be achieved through imp</span><span style="font-family:Verdana;">lementation of good training, strong partnerships, carefully</span><span style="font-family:Verdana;"> considered on ground practices and appropriate and effective techniques.展开更多
A new structural design for the vent stack with an inclined exit was proposed to reduce the settlement hazard of the cryogenic plume from a cryogenic wind tunnel;it extends the plume trajectory to increase the effecti...A new structural design for the vent stack with an inclined exit was proposed to reduce the settlement hazard of the cryogenic plume from a cryogenic wind tunnel;it extends the plume trajectory to increase the effective contact space and time for mixing between the plume gas and atmospheric air before the plume settles to the ground,contributing to more efficient energy consumption for heating.Reduced-scale experiments and numerical simulations of plume dispersion based on vertical and 30°-and 45°-inclined exits were conducted to study harm reduction and energy-saving potential.Analyses of the minimum temperature and minimum oxygen concentration of the plume near the ground indicate that the new exhaust design with an inclined exit clearly reduces the settlement hazard.Under windless conditions and without using a fan-ejector system,up to 15.9%of the heating energy used by the burner can be saved by adopting the new design.展开更多
基金funded by the National Natural Science Foundation of China(41790463 and 41674058)
文摘The Wenchuan earthquake is a natural disaster. Its occurrence and aftermath have demonstrated the critical roles of seismology and earthquake engineering in reducing seismic hazards and damages. However,their existing limitations should also be underscored. This article summarized and reviewed the current scientific understanding of earthquake ruptures, and new insights gained since the Wenchuan event. This study focused on the related challenges to seismology and earthquake engineering as follows:(1) The under-estimation of earthquake risks before occurrences.(2) The current limited data regarding large earthquakes in continental thrust fault systems.(3) The causal relationship between the Wenchuan earthquake and the reservoir impoundment in its vicinity.(4) The identification of low-velocity zone in the crust and its seismogenical role.(5) The casualties and economic losses from a cascade of diverse natural hazards triggered by the ruptures, and the excellent earthquake resistance associated with tunnels in mountainous terrain.
文摘In recent years,natural disasters in coastal areas have become more frequent due to sea level rise and other impact factors under the scenario of global warming,causing great losses to human society.Mangrove forest,an important shelterbelt in coastal areas,plays an extremely important role in reducing the coastal hazards risk.In this paper,the effects of mangrove ecosystem on coastal hazards reduction are reviewed from the aspects of wind prevention,wave attenuation,sedimentation acceleration,tsunamis mitigation,and provide theoretical support and technical guidance for the protection and cultivation of mangrove forests.
文摘This paper considers and describes the cool burning techniques long utilized by Australian Indigenous people as a contributor to bushfire mitigation. Indigenous fire management involves lighting the </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">“</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">cool</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">”</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> fires in selected areas between March and July, in Australia, during the early dry season. The fires burn gradually, reducing fuel loads and creating fire breaks and not all of the area</span><span style="font-family:Verdana;"> is burnt. Late in the dry season, when the weather is</span><span style="font-family:Verdana;"> very hot, the method </span><span style="font-family:Verdana;">removes fuel for larger fires while maintaining and protecting habitat for mammals</span><span style="font-family:Verdana;">, reptiles, insects and birds. The management of Indigenous cultural fire offers an Indigenous viewpoint for wider control of fire and cultural fire </span><span style="font-family:Verdana;">management is an opportunity for collaborations to encourage Aboriginal empo</span><span style="font-family:Verdana;">werment with public and private sector organisations. Effective cool burning in contemporary prescribed burning activities can be achieved through imp</span><span style="font-family:Verdana;">lementation of good training, strong partnerships, carefully</span><span style="font-family:Verdana;"> considered on ground practices and appropriate and effective techniques.
基金supported by the Key Research and Development Program of Zhejiang Province(No.2020C01029),China。
文摘A new structural design for the vent stack with an inclined exit was proposed to reduce the settlement hazard of the cryogenic plume from a cryogenic wind tunnel;it extends the plume trajectory to increase the effective contact space and time for mixing between the plume gas and atmospheric air before the plume settles to the ground,contributing to more efficient energy consumption for heating.Reduced-scale experiments and numerical simulations of plume dispersion based on vertical and 30°-and 45°-inclined exits were conducted to study harm reduction and energy-saving potential.Analyses of the minimum temperature and minimum oxygen concentration of the plume near the ground indicate that the new exhaust design with an inclined exit clearly reduces the settlement hazard.Under windless conditions and without using a fan-ejector system,up to 15.9%of the heating energy used by the burner can be saved by adopting the new design.