It is well known that for non-linear Hamiltonian systems there exist ordered regions with quasi-periodic orbits and regions with chaotic orbits. Usually, these regions are distributed in the phase space in very compli...It is well known that for non-linear Hamiltonian systems there exist ordered regions with quasi-periodic orbits and regions with chaotic orbits. Usually, these regions are distributed in the phase space in very complicated ways, which often makes it very difficult to distinguish between them, especially when we are dealing with many degrees of freedom. Recently, a new, very fast and easy to compute indicator of the chaotic or ordered nature of orbits has been introduced by Zotos (2012), the so-called "Fast Norm Vector Indicator (FNV1)". Using the double pendulum system, in the paper we present a detailed numerical study comporting the advantages and the drawbacks of the FNVI to those of the Smaller Alignment Index (SALI), a reliable indicator of chaos and order in Hamiltonian systems. Our effort was focused both on the traditional behavior of the FNVI for regular and fully developed chaos but on the "sticky" orbits and on the quantitative criterion proposed by Zotos, too.展开更多
We successfully employ an automatic centroid moment tensor(CMT) inversion system to infer the CMT solutions of the February 12,2014 MS7.3 Yutian,Xinjiang earthquake using near-field seismic waveforms(4° < △ &...We successfully employ an automatic centroid moment tensor(CMT) inversion system to infer the CMT solutions of the February 12,2014 MS7.3 Yutian,Xinjiang earthquake using near-field seismic waveforms(4° < △ < 12°) observed by the virtual China seismic networks,which have been recently set up.The results indicate that this event occurred on a rupture plane(strike 243°,dip 70°,and rake-18°),showing left-lateral strike-slip faulting with a minor normal-faulting component.The centroid in the horizontal direction is located nearly 13 km east of the epicenter(36.123° N,82.499° E),and the best-fitting centroid depth is around 10 km.The total scalar moment,M0,is retrieved with an average value of 3.05 × 1019N·m,corresponding to moment magnitude MW6.92.Most of the energy is released within about 14 s.Moreover,we discuss about the potential application of this system in earthquake disaster decision.展开更多
文摘It is well known that for non-linear Hamiltonian systems there exist ordered regions with quasi-periodic orbits and regions with chaotic orbits. Usually, these regions are distributed in the phase space in very complicated ways, which often makes it very difficult to distinguish between them, especially when we are dealing with many degrees of freedom. Recently, a new, very fast and easy to compute indicator of the chaotic or ordered nature of orbits has been introduced by Zotos (2012), the so-called "Fast Norm Vector Indicator (FNV1)". Using the double pendulum system, in the paper we present a detailed numerical study comporting the advantages and the drawbacks of the FNVI to those of the Smaller Alignment Index (SALI), a reliable indicator of chaos and order in Hamiltonian systems. Our effort was focused both on the traditional behavior of the FNVI for regular and fully developed chaos but on the "sticky" orbits and on the quantitative criterion proposed by Zotos, too.
基金funded by Special Oceanic Scientific Research Program(201405026)Science for Earthquake Resilience Program(XH12060Y)Special Seismological Industry Research Program(201208003)
文摘We successfully employ an automatic centroid moment tensor(CMT) inversion system to infer the CMT solutions of the February 12,2014 MS7.3 Yutian,Xinjiang earthquake using near-field seismic waveforms(4° < △ < 12°) observed by the virtual China seismic networks,which have been recently set up.The results indicate that this event occurred on a rupture plane(strike 243°,dip 70°,and rake-18°),showing left-lateral strike-slip faulting with a minor normal-faulting component.The centroid in the horizontal direction is located nearly 13 km east of the epicenter(36.123° N,82.499° E),and the best-fitting centroid depth is around 10 km.The total scalar moment,M0,is retrieved with an average value of 3.05 × 1019N·m,corresponding to moment magnitude MW6.92.Most of the energy is released within about 14 s.Moreover,we discuss about the potential application of this system in earthquake disaster decision.