It has been observed for a long time that the high-frequency fall-off constant of source spectra is about 2 for 'large'earthquakes and about 3 for 'small' earthquakes. For earthquakes between 'larg...It has been observed for a long time that the high-frequency fall-off constant of source spectra is about 2 for 'large'earthquakes and about 3 for 'small' earthquakes. For earthquakes between 'large' and 'small', the high-frequencyfall-off constant is not an integer and varies with the size of the earthquake. In this article such a variation is explainedin the perspective of the scaling of stress drop, which proposes a new approach to the study of the scaling of stress dropusing seismic data with lower quality of completeness and high-frequency characteristics. The study on the sourcespectra of the aftershocks of the 1988 Lancang-Gengma, Yunnan, China earthquake shows that the high-frequencyfall-off of source spectra and its variation with the size of earthquake can be well explained by the model that for 'large'earthquakes the stress drop is a constant while for ',small' earthquakes the stress drop increases with the size of theearthquake.展开更多
The parametric instability behavior of a liquid mercury sessile drop under high frequency Amplitude-Modulate Magnetic Field(AMMF),i.e.a high frequency magnetic field(carder wave)modulated by a low frequency sine wave(...The parametric instability behavior of a liquid mercury sessile drop under high frequency Amplitude-Modulate Magnetic Field(AMMF),i.e.a high frequency magnetic field(carder wave)modulated by a low frequency sine wave(modulate wave),is investigated experimentally.The free surface contour of the mercury drop is observed by a CCD camera while varying the frequency and amplitude of the high frequency AMMF.At a given frequency and amplitude,the edge deformations with an azimuthal wave numbers(modes n=3,4,5,6)were excited.展开更多
A novel Cooperative Directional inter-cell Handover Scheme(CDHS) for High Altitude Platform(HAP) communications systems is proposed,in which the handover target cell and the two cells adjacent to this handover target ...A novel Cooperative Directional inter-cell Handover Scheme(CDHS) for High Altitude Platform(HAP) communications systems is proposed,in which the handover target cell and the two cells adjacent to this handover target cell work cooperatively to exploit the traffic fluctuation to improve handover performance.Users in the overlap area of the overloaded handover target cell will be forced to handover directionally before their optimal handover boundary in order to free up resources for the handover calls which would otherwise be dropped due to the shortage of resources and queue time out.Simulation results show that the handover call dropping probability is greatly reduced(at least 60%) compared with the general queue handover scheme,with little performance reduction to the call blocking probability,and the Not in the Best Cell(NBC) average time is only increased moderately.Moreover,an optimal cell radius can be achieved for a specific platform speed by minimizing the unified system performance,which is the linear combination of the handover call dropping probability and the NBC average time.展开更多
Low-velocity drop-weight impact experiments on individual and multiple Cyclotetramethylene tetranitramine (HMX) energetic particles were performed using a modified drop-weight machine equipped with high-speed photogra...Low-velocity drop-weight impact experiments on individual and multiple Cyclotetramethylene tetranitramine (HMX) energetic particles were performed using a modified drop-weight machine equipped with high-speed photography components. Multiple particles experienced more severe burning reactions than an individual particle. Comparisons between impacted salt and HMX particle show that jetting in HMX is mainly due to the motion of fragmented particles driven by gaseous reaction products. Velocity of jetting, flame propagation, and area expansion were measured via image processing, making it possible to quantify the chemical reaction or mechanical deformation violence at different stages.展开更多
A schwannoma is a benign soft tissue tumor composed of Schwann cells. Clinically, the tumor is slow-growing and usually asymptomatic, rarely developing neurological symptoms. We present a case of a 44-year-old female ...A schwannoma is a benign soft tissue tumor composed of Schwann cells. Clinically, the tumor is slow-growing and usually asymptomatic, rarely developing neurological symptoms. We present a case of a 44-year-old female who was diagnosed with an incomplete high radial nerve palsy, showing a wrist drop and extension of fingers due to schwannoma on the radial nerve of the upper arm. The patient showed excellent result after excision of the schwannoma and neurorrhaphy of the radial nerve.展开更多
Based on the data from a special project titled China's Offshore Marine Integrated Investigation and Evaluation as well as Regional Ocean Modeling Systems(ROMS)diagnostic numerical model,we studied the influence o...Based on the data from a special project titled China's Offshore Marine Integrated Investigation and Evaluation as well as Regional Ocean Modeling Systems(ROMS)diagnostic numerical model,we studied the influence of high wind processes on the circulation and water exchange between the Bohai and Yellow Seas(BYS)in winter.The results show that the vertical structure of the Yellow Sea Warm Current(YSWC)is relatively uniform under condition of high winds,showing obvious barotropic features.However,this flow is not a stable mean flow,showing strong paroxysmal and reciprocating characteristics.A comparison of the changes in sea level suggests that the intensity of the northwards upwind flow is consistent with the abnormal fluctuations in the sea level.It indicates that the upwind flow is closely related to the water exchange between the BYS.The impact of high wind processes on the water exchange between the BYS is enormous.It can make the flux through the Bohai Strait,as well as that through the mouth of each constituent bay(i.e.,Liaodong Bay,Bohai Bay,and Laizhou Bay)far greater than usual,resulting in a significant increase in the water exchange rate.The exchange capacity,which is about 8%of the total volume of the Bohai Sea,can be completed in a few days.Therefore,the water exchange of the Bohai Sea may be completed by only a few occasional high wind processes in winter.展开更多
文摘It has been observed for a long time that the high-frequency fall-off constant of source spectra is about 2 for 'large'earthquakes and about 3 for 'small' earthquakes. For earthquakes between 'large' and 'small', the high-frequencyfall-off constant is not an integer and varies with the size of the earthquake. In this article such a variation is explainedin the perspective of the scaling of stress drop, which proposes a new approach to the study of the scaling of stress dropusing seismic data with lower quality of completeness and high-frequency characteristics. The study on the sourcespectra of the aftershocks of the 1988 Lancang-Gengma, Yunnan, China earthquake shows that the high-frequencyfall-off of source spectra and its variation with the size of earthquake can be well explained by the model that for 'large'earthquakes the stress drop is a constant while for ',small' earthquakes the stress drop increases with the size of theearthquake.
基金Item Sponsored by National Natural Science Foundation of China (No.59874133) Creation Foundation of Shanghai Educational Committee (No.10YZ16)
文摘The parametric instability behavior of a liquid mercury sessile drop under high frequency Amplitude-Modulate Magnetic Field(AMMF),i.e.a high frequency magnetic field(carder wave)modulated by a low frequency sine wave(modulate wave),is investigated experimentally.The free surface contour of the mercury drop is observed by a CCD camera while varying the frequency and amplitude of the high frequency AMMF.At a given frequency and amplitude,the edge deformations with an azimuthal wave numbers(modes n=3,4,5,6)were excited.
基金Supported by the China Scholarship Council (2008611011)Doctoral Fund of Ministry of Education of China(20094307110004)
文摘A novel Cooperative Directional inter-cell Handover Scheme(CDHS) for High Altitude Platform(HAP) communications systems is proposed,in which the handover target cell and the two cells adjacent to this handover target cell work cooperatively to exploit the traffic fluctuation to improve handover performance.Users in the overlap area of the overloaded handover target cell will be forced to handover directionally before their optimal handover boundary in order to free up resources for the handover calls which would otherwise be dropped due to the shortage of resources and queue time out.Simulation results show that the handover call dropping probability is greatly reduced(at least 60%) compared with the general queue handover scheme,with little performance reduction to the call blocking probability,and the Not in the Best Cell(NBC) average time is only increased moderately.Moreover,an optimal cell radius can be achieved for a specific platform speed by minimizing the unified system performance,which is the linear combination of the handover call dropping probability and the NBC average time.
基金supported by the National Natural Science Foundation of China (Grants 11572045 and 11472051)the Defense Industrial Technology Development Program (Grant B1520132004)the General Project of the CAEP Safety and Ammunition Center (Grant RMC2015B03)
文摘Low-velocity drop-weight impact experiments on individual and multiple Cyclotetramethylene tetranitramine (HMX) energetic particles were performed using a modified drop-weight machine equipped with high-speed photography components. Multiple particles experienced more severe burning reactions than an individual particle. Comparisons between impacted salt and HMX particle show that jetting in HMX is mainly due to the motion of fragmented particles driven by gaseous reaction products. Velocity of jetting, flame propagation, and area expansion were measured via image processing, making it possible to quantify the chemical reaction or mechanical deformation violence at different stages.
文摘A schwannoma is a benign soft tissue tumor composed of Schwann cells. Clinically, the tumor is slow-growing and usually asymptomatic, rarely developing neurological symptoms. We present a case of a 44-year-old female who was diagnosed with an incomplete high radial nerve palsy, showing a wrist drop and extension of fingers due to schwannoma on the radial nerve of the upper arm. The patient showed excellent result after excision of the schwannoma and neurorrhaphy of the radial nerve.
基金Supported by the National Natural Science Foundation of China(Nos.41506034,41676004,41376001,41430963)the Basic Scientific Fund for National Public Research Institutes of China(No.GY0213G02)+1 种基金the National Program on Global Change and Air-Sea Interaction(No.GASIGEOGE-03)the National Key Research and Development Program(No.2016YFA0600900)
文摘Based on the data from a special project titled China's Offshore Marine Integrated Investigation and Evaluation as well as Regional Ocean Modeling Systems(ROMS)diagnostic numerical model,we studied the influence of high wind processes on the circulation and water exchange between the Bohai and Yellow Seas(BYS)in winter.The results show that the vertical structure of the Yellow Sea Warm Current(YSWC)is relatively uniform under condition of high winds,showing obvious barotropic features.However,this flow is not a stable mean flow,showing strong paroxysmal and reciprocating characteristics.A comparison of the changes in sea level suggests that the intensity of the northwards upwind flow is consistent with the abnormal fluctuations in the sea level.It indicates that the upwind flow is closely related to the water exchange between the BYS.The impact of high wind processes on the water exchange between the BYS is enormous.It can make the flux through the Bohai Strait,as well as that through the mouth of each constituent bay(i.e.,Liaodong Bay,Bohai Bay,and Laizhou Bay)far greater than usual,resulting in a significant increase in the water exchange rate.The exchange capacity,which is about 8%of the total volume of the Bohai Sea,can be completed in a few days.Therefore,the water exchange of the Bohai Sea may be completed by only a few occasional high wind processes in winter.
