The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the ...The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the relationship between sedimentary particles and geomorphic processes,mechanisms for the formation of characteristics of grain size composition were investigated by analyzing grain size parameters and external dynamic geomorphologic features.Firstly,the grain size parameters of the riverbed,stream power,maximum grain size of the wind-blown particles and HI values of the mainstream channel were calculated and analyzed,and they were used to establish multiple regression functions of grain size parameters in order to determine the effects of wind and river actions on particles.The results show that sediments in different reaches are formed in different environments：the upper stream is controlled by fluvial and aeolian processes;the sorting properties of riverbed sediments in the middle stream are worse than those in the upper stream since they are affected mainly by fluvial processes as indicated by the larger stream power there;and the particles on the downstream riverbed are likely contributed by the Kubuqi Desert.The size of particles on the riverbed depends on the hydrodynamic conditions,but is not significantly associated with the evolution of landform.Sorting is significantly related to both the hydrodynamic conditions and wind actions.Riverbed deposits brought in by winds likely become finer from the lower to the upper reaches,which are not coarser than 0.88Φ.Generally speaking,the stream power has a major effect on sedimentation characteristics of the riverbed,followed by wind power.展开更多
In this paper we use a binomial tree to price convertible bond with default risk. A new way about pricing convertible bonds is proposed, which belongs to the deduced form approach. Firstly an inhomogeneous Possion pro...In this paper we use a binomial tree to price convertible bond with default risk. A new way about pricing convertible bonds is proposed, which belongs to the deduced form approach. Firstly an inhomogeneous Possion process is used to describe default event and definition of default time. Secondly we combine the stock binomial tree with default intensity and obtain a new tree, then convertible bonds are priced according to the combined tree. It is worth pointing out that the model have following characters： simple, intuitive and having the strong ability to combine other items in convertible bonds＇ indenture.展开更多
基金National Natural Science Foundation of China(4137103641671004)
文摘The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the relationship between sedimentary particles and geomorphic processes,mechanisms for the formation of characteristics of grain size composition were investigated by analyzing grain size parameters and external dynamic geomorphologic features.Firstly,the grain size parameters of the riverbed,stream power,maximum grain size of the wind-blown particles and HI values of the mainstream channel were calculated and analyzed,and they were used to establish multiple regression functions of grain size parameters in order to determine the effects of wind and river actions on particles.The results show that sediments in different reaches are formed in different environments：the upper stream is controlled by fluvial and aeolian processes;the sorting properties of riverbed sediments in the middle stream are worse than those in the upper stream since they are affected mainly by fluvial processes as indicated by the larger stream power there;and the particles on the downstream riverbed are likely contributed by the Kubuqi Desert.The size of particles on the riverbed depends on the hydrodynamic conditions,but is not significantly associated with the evolution of landform.Sorting is significantly related to both the hydrodynamic conditions and wind actions.Riverbed deposits brought in by winds likely become finer from the lower to the upper reaches,which are not coarser than 0.88Φ.Generally speaking,the stream power has a major effect on sedimentation characteristics of the riverbed,followed by wind power.
基金This project is supported by National Natural Science Foundation of China （70440011） and Natural Science Found of Beijing （1052007）.
文摘In this paper we use a binomial tree to price convertible bond with default risk. A new way about pricing convertible bonds is proposed, which belongs to the deduced form approach. Firstly an inhomogeneous Possion process is used to describe default event and definition of default time. Secondly we combine the stock binomial tree with default intensity and obtain a new tree, then convertible bonds are priced according to the combined tree. It is worth pointing out that the model have following characters： simple, intuitive and having the strong ability to combine other items in convertible bonds＇ indenture.
