The mobile Intemet industry has exp- erienced dramatic changes as plenty of new applications and business models emerged. This study conducts a qualitative review on the changes through adopting business ecosystem app...The mobile Intemet industry has exp- erienced dramatic changes as plenty of new applications and business models emerged. This study conducts a qualitative review on the changes through adopting business ecosystem approaches. An analytical framework is estab- lished for reviewing the structure of mobile Internet business ecosystem. Then the core value, key actors, and inter-firm relationships of the mobile Internet ecosystem in the past and in the present are compared. It is found that the ecosystem structure has shifted from an MNO-centric model to a polycentric one with highly expanded value sources and di- versified keystone players. Accordingly some suggestions for regulatory policy makers are provided in terms of the roles of mobile Inter- net in social welfare improvement, the call for a convergent regulatory system, and chal- lenges for information security regulation.展开更多
In this study,based on the body wave arrival data of 5506 earthquakes recorded by 32 fi xed stations and 94 temporary stations in Yangbi and surrounding areas,the source parameters of Yangbi Ms6.4 earthquake sequence ...In this study,based on the body wave arrival data of 5506 earthquakes recorded by 32 fi xed stations and 94 temporary stations in Yangbi and surrounding areas,the source parameters of Yangbi Ms6.4 earthquake sequence and three-dimensional(3-D)fi ne Vp,Vs,and Vp/Vs were inverted by using the consistency-constrained double-diff erence tomography method.The results showed that the focal depth after relocation was mostly in the range of 3–10 km,evidently nearly horizontally distributed,and concentrated in the weak area of the high-velocity body or at the side of the high-low-velocity body transition zone toward the high-velocity body,showing a good corresponding relationship with the velocity structure.The velocity structure in the Yangbi area has remarkably uneven characteristics.The seismic activity area is dominated by high-velocity bodies prone to brittle fracture near the surface.As the depth increases,low-velocity anomalies appear.A signifi cant diff erence was observed in the wave velocity ratio between the upper and lower sides of the seismically dense strip.Based on the focal mechanism of the Yangbi Ms6.4 earthquake and the fine 3-D velocity structure,this article concludes that the Yangbi Ms6.4 earthquake was caused by a strong regional tectonic stress concentrated in the relatively weak area by hard high-velocity bodies on the northwest sides.The Ms5.6 foreshock broke the inherent balance of regional stress and promoted the occurrence of the Yangbi Ms6.4 mainshock.Afterward,the stress was adjusted to a new equilibrium state through a large number of aftershocks,forming a foreshock–mainshock–aftershock type of seismic activity model.Based on the activity law of the Yangbi Ms6.4 earthquake sequence and characteristics of the 3D velocity structure distribution,this paper speculates that the seismogenic structure of the Yangbi earthquake was possibly a northwest strike-slip buried fault with a depth of 3–10 km on the southwest side of the Weixi–Qiaohou fault.展开更多
The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the d...The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the differential game with a coalition structure is proposed. A few assumptions about the deviation instant for a coalition are made concerning the behavior of a group of many individuals in certain dynamic environments.From these, the time-consistent cooperative agreement can be strategically supported by ε-Nash or strong ε-Nash equilibria. While in games in the extensive form with perfect information, it is somewhat surprising that without the assumptions of deviation instant for a coalition, Nash or strong Nash equilibria can be constructed.展开更多
基金supported by the China Fundamental Research Funds for the Central Universities under Grant No.BUPT2012RC1011
文摘The mobile Intemet industry has exp- erienced dramatic changes as plenty of new applications and business models emerged. This study conducts a qualitative review on the changes through adopting business ecosystem approaches. An analytical framework is estab- lished for reviewing the structure of mobile Internet business ecosystem. Then the core value, key actors, and inter-firm relationships of the mobile Internet ecosystem in the past and in the present are compared. It is found that the ecosystem structure has shifted from an MNO-centric model to a polycentric one with highly expanded value sources and di- versified keystone players. Accordingly some suggestions for regulatory policy makers are provided in terms of the roles of mobile Inter- net in social welfare improvement, the call for a convergent regulatory system, and chal- lenges for information security regulation.
基金supported by the Research Project of Tianjin Earthquake Agency (No. Yb202101, Zd202101)
文摘In this study,based on the body wave arrival data of 5506 earthquakes recorded by 32 fi xed stations and 94 temporary stations in Yangbi and surrounding areas,the source parameters of Yangbi Ms6.4 earthquake sequence and three-dimensional(3-D)fi ne Vp,Vs,and Vp/Vs were inverted by using the consistency-constrained double-diff erence tomography method.The results showed that the focal depth after relocation was mostly in the range of 3–10 km,evidently nearly horizontally distributed,and concentrated in the weak area of the high-velocity body or at the side of the high-low-velocity body transition zone toward the high-velocity body,showing a good corresponding relationship with the velocity structure.The velocity structure in the Yangbi area has remarkably uneven characteristics.The seismic activity area is dominated by high-velocity bodies prone to brittle fracture near the surface.As the depth increases,low-velocity anomalies appear.A signifi cant diff erence was observed in the wave velocity ratio between the upper and lower sides of the seismically dense strip.Based on the focal mechanism of the Yangbi Ms6.4 earthquake and the fine 3-D velocity structure,this article concludes that the Yangbi Ms6.4 earthquake was caused by a strong regional tectonic stress concentrated in the relatively weak area by hard high-velocity bodies on the northwest sides.The Ms5.6 foreshock broke the inherent balance of regional stress and promoted the occurrence of the Yangbi Ms6.4 mainshock.Afterward,the stress was adjusted to a new equilibrium state through a large number of aftershocks,forming a foreshock–mainshock–aftershock type of seismic activity model.Based on the activity law of the Yangbi Ms6.4 earthquake sequence and characteristics of the 3D velocity structure distribution,this paper speculates that the seismogenic structure of the Yangbi earthquake was possibly a northwest strike-slip buried fault with a depth of 3–10 km on the southwest side of the Weixi–Qiaohou fault.
基金supported by National Natural Science Foundation of China(Grant Nos.7117112071373262 and 71571108)+3 种基金Projects of International(Regional)Cooperation and Exchanges of National Natural Science Foundation of China(Grant No.71411130215)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20133706110002)Natural Science Foundation of Shandong Province of China(Grant No.ZR2015GZ007)Saint Petersburg State University(Grant No.9.38.245.2014)
文摘The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the differential game with a coalition structure is proposed. A few assumptions about the deviation instant for a coalition are made concerning the behavior of a group of many individuals in certain dynamic environments.From these, the time-consistent cooperative agreement can be strategically supported by ε-Nash or strong ε-Nash equilibria. While in games in the extensive form with perfect information, it is somewhat surprising that without the assumptions of deviation instant for a coalition, Nash or strong Nash equilibria can be constructed.
