The deep reason of severe disaster weather with the relationship among the earth nutation,rotation and atmospheric change is explored based on the effective results about the disaster weather prediction of the long te...The deep reason of severe disaster weather with the relationship among the earth nutation,rotation and atmospheric change is explored based on the effective results about the disaster weather prediction of the long term made by the variation of the earth rotation in near 10 years. It is discussed the relationship between the subtropical anticyclone and subtropical easterlies to aim at the problem of high temperature and drought in the globe,further more,the comparison analysis has been made to the earth nutation and the variation of rotation. The research results show that the reasons of severe disaster weather not only are due to atmosphere itself,but have some variation information of earth movement which could be used for the weather forecast.展开更多
Narrowband radar has been successfully used for high resolution imaging of fast rotating targets by exploiting their micro-motion features.In some practical situations,however,the target image may suffer from aliasing...Narrowband radar has been successfully used for high resolution imaging of fast rotating targets by exploiting their micro-motion features.In some practical situations,however,the target image may suffer from aliasing due to the fixed pulse repetition interval(PRI)of traditional radar scheme.In this work,the random PRI signal associated with compressed sensing(CS)theory was introduced for aliasing reduction to obtain high resolution images of fast rotating targets.To circumvent the large-scale dictionary and high computational complexity problem arising from direct application of CS theory,the low resolution image was firstly generated by applying a modified generalized Radon transform on the time-frequency domain,and then the dictionary was scaled down by random undersampling as well as the atoms extraction according to those strong scattering areas of the low resolution image.The scale-down-dictionary CS(SDD-CS)processing scheme was detailed and simulation results show that the SDD-CS scheme for narrowband radar can achieve preferable images with no aliasing as well as acceptable computational cost.展开更多
A new method for spin assignment of superdeformed rotational bands is proposed and it turns out to be more efficient than other methods used before. The application is made to superdeformed bands in A ～ 190 and A ～ ...A new method for spin assignment of superdeformed rotational bands is proposed and it turns out to be more efficient than other methods used before. The application is made to superdeformed bands in A ～ 190 and A ～ 150 mass regions. By analyzing the standard deviation of the fixed γ-ray energies of an SD band in different methods,the advantage of the present method over the other methods is presented. This method brings then a comprehensive interpretation of the methods used in spin assignment.展开更多
This work investigated the response of Cu46Zr42Al7Y5 glass ribbons to both dynamic and static heating using differential scanning calorimeter （DSC）. The DSC curve manifests three exothermic responses to dynamic heat...This work investigated the response of Cu46Zr42Al7Y5 glass ribbons to both dynamic and static heating using differential scanning calorimeter （DSC）. The DSC curve manifests three exothermic responses to dynamic heating, among which the first and the third one are the signatures of the normal sub-Tg （Tg, glass transition temperature） relaxation and the crystallization process, respectively. The second one is attributed to a partial overlap between the endothermic response to the glass transition and the exothermic response to the formation of ordered clusters. The cluster ordering, which begins at the final stage of glass transition, has been verified by the differences in the activation energy of the sub-Tg relax- ation, the cluster ordering and primary crystallization for both the as-spun and annealed ribbons. The cluster ordering could be driven by the large difference between the Zr-Y mixing enthalpy and the Al-Y （or Cu-Y） mixing enthalpy. The findings contribute to distinguishing between phase separation and clusters motion scenarios.展开更多
基金supported by National Natural Science Foundation of China through Grant( 60674074 )the foundation projects of 2008 LASW-B11,GYHY(QX)2007-6-26,GYHY(QX)2007-6-2, IHR2007K02,FiDAF-2-01, BJG200801,2007AA061901,QD62,KF(2006)11
文摘The deep reason of severe disaster weather with the relationship among the earth nutation,rotation and atmospheric change is explored based on the effective results about the disaster weather prediction of the long term made by the variation of the earth rotation in near 10 years. It is discussed the relationship between the subtropical anticyclone and subtropical easterlies to aim at the problem of high temperature and drought in the globe,further more,the comparison analysis has been made to the earth nutation and the variation of rotation. The research results show that the reasons of severe disaster weather not only are due to atmosphere itself,but have some variation information of earth movement which could be used for the weather forecast.
基金Projects(61171133,61271442)supported by the National Natural Science Foundation of ChinaProject(61025006)supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(B110404)supported by the Innovation Program for Excellent Postgraduates of National University of Defense Technology,China
文摘Narrowband radar has been successfully used for high resolution imaging of fast rotating targets by exploiting their micro-motion features.In some practical situations,however,the target image may suffer from aliasing due to the fixed pulse repetition interval(PRI)of traditional radar scheme.In this work,the random PRI signal associated with compressed sensing(CS)theory was introduced for aliasing reduction to obtain high resolution images of fast rotating targets.To circumvent the large-scale dictionary and high computational complexity problem arising from direct application of CS theory,the low resolution image was firstly generated by applying a modified generalized Radon transform on the time-frequency domain,and then the dictionary was scaled down by random undersampling as well as the atoms extraction according to those strong scattering areas of the low resolution image.The scale-down-dictionary CS(SDD-CS)processing scheme was detailed and simulation results show that the SDD-CS scheme for narrowband radar can achieve preferable images with no aliasing as well as acceptable computational cost.
文摘A new method for spin assignment of superdeformed rotational bands is proposed and it turns out to be more efficient than other methods used before. The application is made to superdeformed bands in A ～ 190 and A ～ 150 mass regions. By analyzing the standard deviation of the fixed γ-ray energies of an SD band in different methods,the advantage of the present method over the other methods is presented. This method brings then a comprehensive interpretation of the methods used in spin assignment.
基金supported by the National Natural Science Foundation of China(5117109051571131)the Fundamental Research Funds of Shandong University(2014YQ008)
文摘This work investigated the response of Cu46Zr42Al7Y5 glass ribbons to both dynamic and static heating using differential scanning calorimeter （DSC）. The DSC curve manifests three exothermic responses to dynamic heating, among which the first and the third one are the signatures of the normal sub-Tg （Tg, glass transition temperature） relaxation and the crystallization process, respectively. The second one is attributed to a partial overlap between the endothermic response to the glass transition and the exothermic response to the formation of ordered clusters. The cluster ordering, which begins at the final stage of glass transition, has been verified by the differences in the activation energy of the sub-Tg relax- ation, the cluster ordering and primary crystallization for both the as-spun and annealed ribbons. The cluster ordering could be driven by the large difference between the Zr-Y mixing enthalpy and the Al-Y （or Cu-Y） mixing enthalpy. The findings contribute to distinguishing between phase separation and clusters motion scenarios.
