Some chaotic sequences generated from maps conjugated with tent map can be reconstructed precisely by short sequence prediction,since the problem of finite precision degrades the statistical properties of chaotic ma...Some chaotic sequences generated from maps conjugated with tent map can be reconstructed precisely by short sequence prediction,since the problem of finite precision degrades the statistical properties of chaotic maps.This paper discusses the topological conjugation properties of the chaotic maps;analyzes in detail the reconstruction process of the chaotic sequences and the security of the oversampled chaotic map (OSCM) binary sequences.The result demonstrates that OSCM binary sequences can sustain the attack of the short sequence prediction,that is,they cant be reconstructed.Furthermore,all attack strategies aiming at the chaotic systems based on synchronization will fail,meaning that they are secure.展开更多
On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial ...On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial order,give the explicit formulations of the monotonicity solution sets A{1;≥,T_1;≤B^(1)}and B{1;≥,T_2≥A^(1)}for the(1)-inverse,and two results of the monotonicity charac teriaztion for the(1,2)-inverse.展开更多
In order to bring graphene materials much closer to real world applications, it is imperative to have simple, efficient and eco-friendly ways to produce processable graphene derivatives. In this study, a hydrophilic l...In order to bring graphene materials much closer to real world applications, it is imperative to have simple, efficient and eco-friendly ways to produce processable graphene derivatives. In this study, a hydrophilic low-temperature thermally functionalized graphene and its super-hydrophobic organically modified graphene derivative were fabricated. A unique structural topology was found and some of the oxygen functionalities were retained on the thermally functionalized graphene surfaces, which facilitated the subsequent highly effective organic modification reaction and led to the super-hydrophobic organically modified graphene with multi functional applications in liquid marbles and polymer nanocomposites. The organic modification reaction also restored the graphenic conjugated structure of the thermally functionalized graphene, particularly for organic modifiers having longer alkyl chains, as confirmed by various characteri- zation techniques such as electrical conductivity measurements, ultraviolet/visible spectroscopy and selected area electron diffraction. The free-standing soft liquid marble was fabricated by wrapping a water droplet with the super-hydrophobic organically modified graphene, and showed potential for use as a microreactor. As for the polymer nanocomposites, a strong interfacial adhesion is believed to exist between an organic polymer matrix and the modified graphene because of the organophilic coating formed on the graphene base, which resulted in large improvements in the thermal and mechanical properties of the polymer nanocomposites with the modified graphene, even at very low loading levels. A new avenue has therefore been opened up for large-scale production of processable graphene derivatives with various practicable applications.展开更多
文摘Some chaotic sequences generated from maps conjugated with tent map can be reconstructed precisely by short sequence prediction,since the problem of finite precision degrades the statistical properties of chaotic maps.This paper discusses the topological conjugation properties of the chaotic maps;analyzes in detail the reconstruction process of the chaotic sequences and the security of the oversampled chaotic map (OSCM) binary sequences.The result demonstrates that OSCM binary sequences can sustain the attack of the short sequence prediction,that is,they cant be reconstructed.Furthermore,all attack strategies aiming at the chaotic systems based on synchronization will fail,meaning that they are secure.
文摘On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial order,give the explicit formulations of the monotonicity solution sets A{1;≥,T_1;≤B^(1)}and B{1;≥,T_2≥A^(1)}for the(1)-inverse,and two results of the monotonicity charac teriaztion for the(1,2)-inverse.
文摘In order to bring graphene materials much closer to real world applications, it is imperative to have simple, efficient and eco-friendly ways to produce processable graphene derivatives. In this study, a hydrophilic low-temperature thermally functionalized graphene and its super-hydrophobic organically modified graphene derivative were fabricated. A unique structural topology was found and some of the oxygen functionalities were retained on the thermally functionalized graphene surfaces, which facilitated the subsequent highly effective organic modification reaction and led to the super-hydrophobic organically modified graphene with multi functional applications in liquid marbles and polymer nanocomposites. The organic modification reaction also restored the graphenic conjugated structure of the thermally functionalized graphene, particularly for organic modifiers having longer alkyl chains, as confirmed by various characteri- zation techniques such as electrical conductivity measurements, ultraviolet/visible spectroscopy and selected area electron diffraction. The free-standing soft liquid marble was fabricated by wrapping a water droplet with the super-hydrophobic organically modified graphene, and showed potential for use as a microreactor. As for the polymer nanocomposites, a strong interfacial adhesion is believed to exist between an organic polymer matrix and the modified graphene because of the organophilic coating formed on the graphene base, which resulted in large improvements in the thermal and mechanical properties of the polymer nanocomposites with the modified graphene, even at very low loading levels. A new avenue has therefore been opened up for large-scale production of processable graphene derivatives with various practicable applications.