With the goal of minimizing the enciphered data redundancy R , we first make a feasibility analysis on the PKCS which is based on the PR method, indicating its difficulties in real ap...With the goal of minimizing the enciphered data redundancy R , we first make a feasibility analysis on the PKCS which is based on the PR method, indicating its difficulties in real applications. Then we generalize the method to such a case that an arbitrary number system can be utilized in the system. We form some conditions that should be satisfied when we want to create security keys, to encipher plaintexts or to decipher cryptograms. Finally, a qualitative analysis is made on the improved PR method with the results that the data redundancy R of enciphered text for the improved PR method is far smaller than that of the primitive PR method and its enciphering and deciphering procedures are accordingly sped up. Moreover, the security of the new scheme is by no means worse than that of the old one.展开更多
Li 2+ x RE x Si 1- x O 3(RE=Pr, Nd, Sm, Gd; x =0～0 15) samples were prepared by the sol gel method. DTA TG, XRD, TEM and A C impedance techniques were used to investigate the structure, sha...Li 2+ x RE x Si 1- x O 3(RE=Pr, Nd, Sm, Gd; x =0～0 15) samples were prepared by the sol gel method. DTA TG, XRD, TEM and A C impedance techniques were used to investigate the structure, shape, and ionic conductivity of these samples. The results show that the range of solid solution formation is in 0< x ≤0 09, in which the conductivity of these samples raises with the increasing amount of RE 2O 3 (RE=Pr, Nd, Sm, Gd) added, and the diameter of the powders is about 100 nm. Compared with the conventional solid state reaction, the sol gel method needs low temperature and presents high ionic conductivity.展开更多
文摘With the goal of minimizing the enciphered data redundancy R , we first make a feasibility analysis on the PKCS which is based on the PR method, indicating its difficulties in real applications. Then we generalize the method to such a case that an arbitrary number system can be utilized in the system. We form some conditions that should be satisfied when we want to create security keys, to encipher plaintexts or to decipher cryptograms. Finally, a qualitative analysis is made on the improved PR method with the results that the data redundancy R of enciphered text for the improved PR method is far smaller than that of the primitive PR method and its enciphering and deciphering procedures are accordingly sped up. Moreover, the security of the new scheme is by no means worse than that of the old one.
文摘Li 2+ x RE x Si 1- x O 3(RE=Pr, Nd, Sm, Gd; x =0～0 15) samples were prepared by the sol gel method. DTA TG, XRD, TEM and A C impedance techniques were used to investigate the structure, shape, and ionic conductivity of these samples. The results show that the range of solid solution formation is in 0< x ≤0 09, in which the conductivity of these samples raises with the increasing amount of RE 2O 3 (RE=Pr, Nd, Sm, Gd) added, and the diameter of the powders is about 100 nm. Compared with the conventional solid state reaction, the sol gel method needs low temperature and presents high ionic conductivity.
