Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there a...Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there are only two identity-based proxy ring signature schemes have been proposed until now, i. e., Cheng＇s scheme and Lang＇s scheme. It＇s unlucky that the two identity-based proxy ring signature schemes are unfeasible. This paper points out the reasons why the two identity-based proxy ring signature schemes are unfeasible. In order to design feasible and efficient identity-based proxy ring signature schemes from bilinear pairings, we have to search for other methods.展开更多
This paper concerns with the bifurcation of limit cycles from a double homoclinic loop under multiple parameter perturbations for general planar systems. The existence conditions of 4 homoclinic bifurcation curves and...This paper concerns with the bifurcation of limit cycles from a double homoclinic loop under multiple parameter perturbations for general planar systems. The existence conditions of 4 homoclinic bifurcation curves and small and large limit cycles are especially investigated.展开更多
A contravaried bilinear pairing X on every M(ρ) × M(ρθ) is determined and it is provedthat M(ρ)is irreducible if and only if K is left nondegellerate. It is also proved that every cyclicpointed module is a qu...A contravaried bilinear pairing X on every M(ρ) × M(ρθ) is determined and it is provedthat M(ρ)is irreducible if and only if K is left nondegellerate. It is also proved that every cyclicpointed module is a quotient of some Verma-like poillted module; moreover if it is irreduciblethen it is a quotieDt of the Vermarlike poiDted module by the left kernel of some bilinearpairing K. In case the mass fUnction is symmetric, there exists a bilinear form on M(ρ). It isproved that unitals pointed modules are integrable. In addition, a characterization of the massfunctions of Kac-Moody algebras is given, which is a generalization of the finite dimensionalLie algebras case.展开更多
基金Supported by the National Natural Science Foundation of China （No.60432040）.
文摘Recently, proxy ring signature schemes have been shown to be useful in various applications, such as electronic polling, electronic payment, etc. Although many proxy ring signature schemes have been pro-posed, there are only two identity-based proxy ring signature schemes have been proposed until now, i. e., Cheng＇s scheme and Lang＇s scheme. It＇s unlucky that the two identity-based proxy ring signature schemes are unfeasible. This paper points out the reasons why the two identity-based proxy ring signature schemes are unfeasible. In order to design feasible and efficient identity-based proxy ring signature schemes from bilinear pairings, we have to search for other methods.
基金Project supported by the National Natural Science Foundation of China (No.10371072) the Ministry of Education of China (No.20010248019, No.20020248010).
文摘This paper concerns with the bifurcation of limit cycles from a double homoclinic loop under multiple parameter perturbations for general planar systems. The existence conditions of 4 homoclinic bifurcation curves and small and large limit cycles are especially investigated.
文摘A contravaried bilinear pairing X on every M(ρ) × M(ρθ) is determined and it is provedthat M(ρ)is irreducible if and only if K is left nondegellerate. It is also proved that every cyclicpointed module is a quotient of some Verma-like poillted module; moreover if it is irreduciblethen it is a quotieDt of the Vermarlike poiDted module by the left kernel of some bilinearpairing K. In case the mass fUnction is symmetric, there exists a bilinear form on M(ρ). It isproved that unitals pointed modules are integrable. In addition, a characterization of the massfunctions of Kac-Moody algebras is given, which is a generalization of the finite dimensionalLie algebras case.
