Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits....Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.展开更多
Two 1-methyl-1H-benzo[d]imidazole derivatives, C_（18）H_（14）CuN_4O_4·C_4H_8O_2（1） and C_9H_9N_3O（2）, have been synthesized and characterized by NMR, MS, FT-IR, elementary analysis and X-ray single-crystal ...Two 1-methyl-1H-benzo[d]imidazole derivatives, C_（18）H_（14）CuN_4O_4·C_4H_8O_2（1） and C_9H_9N_3O（2）, have been synthesized and characterized by NMR, MS, FT-IR, elementary analysis and X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group P2_1/n with a = 9.6888（3）, b = 7.3772（2）, c = 14.3277（4）A, β = 95.819（3）°, V = 1018.81（5） A3, M_r = 501.98, Z = 2, D_c = 1.636 g/cm^3, F（000） = 518, μ = 1.123 mm^（-1）, MoKα radiation（λ = 0.71073 A）, the final R = 0.0325 and wR = 0.0859 for 1821 observed reflections with I 〉 2σ（I）. Compound 2 crystallizes in monoclinic, space group C2/c with a = 14.2908（14）, b = 14.4268（13）, c = 8.4802（6） A, β = 108.513（9）o, V = 1657.9（3） A3, M_r = 175.19, Z = 8, D_c = 1.404 g/cm^3, F（000） = 736, μ = 0.097 mm^（-1）, Mo Kα radiation（λ = 0.71073 A）, the final R = 0.0563 and wR = 0.1531 for 1231 observed reflections with I 〉 2σ（I）. Intermolecular（N-H···N, N-H···O） and intramolecular（N-H···N, C-H···O） hydrogen bonds, as well as C-H···π and π-π stacking interactions, help to stabilize the crystal structure of compound 2.展开更多
基金Project (No. 200442) supported by the Electronics DevelopmentFoundation for the Key Industrialization Project of the Ministry of0Information Industry, China
文摘Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.
基金Supported by the National Natural Science Foundation of China(No.31370373 and 21102084)Natural Science Foundation of Hubei Province(No.2012FKC14401)
文摘Two 1-methyl-1H-benzo[d]imidazole derivatives, C_（18）H_（14）CuN_4O_4·C_4H_8O_2（1） and C_9H_9N_3O（2）, have been synthesized and characterized by NMR, MS, FT-IR, elementary analysis and X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group P2_1/n with a = 9.6888（3）, b = 7.3772（2）, c = 14.3277（4）A, β = 95.819（3）°, V = 1018.81（5） A3, M_r = 501.98, Z = 2, D_c = 1.636 g/cm^3, F（000） = 518, μ = 1.123 mm^（-1）, MoKα radiation（λ = 0.71073 A）, the final R = 0.0325 and wR = 0.0859 for 1821 observed reflections with I 〉 2σ（I）. Compound 2 crystallizes in monoclinic, space group C2/c with a = 14.2908（14）, b = 14.4268（13）, c = 8.4802（6） A, β = 108.513（9）o, V = 1657.9（3） A3, M_r = 175.19, Z = 8, D_c = 1.404 g/cm^3, F（000） = 736, μ = 0.097 mm^（-1）, Mo Kα radiation（λ = 0.71073 A）, the final R = 0.0563 and wR = 0.1531 for 1231 observed reflections with I 〉 2σ（I）. Intermolecular（N-H···N, N-H···O） and intramolecular（N-H···N, C-H···O） hydrogen bonds, as well as C-H···π and π-π stacking interactions, help to stabilize the crystal structure of compound 2.
