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Dongjie, China

The Communication University of China is a public university in Beijing, China. Formerly known as the Beijing Broadcasting Institute it is one of the Project 211 and 985 platform key universities directly administered by the Ministry of Education of the People's Republic of China.The predecessor of the school was a training center for technicians of the Central Broadcasting Bureau that was founded in 1954. In April of 1959, the school was upgraded to the Beijing Broadcasting Institute approved by the State Council. In August of 2004, the BBI was renamed into the Communication University of China. CUC has trained, since its establishment in 1954, numerous high-level professionals for the Chinese media industry, and made a significant contribution to the nation’s media business and economy. It has been honored as the “cradle of the nation’s broadcasting and television talents”. The university now provides undergraduate, master and doctoral degree courses for full-time students, and diploma training courses for media professionals.Communication University of China is one of the top public universities in China. It is ranked No.1 of media education and ranked No.1 among language universities in China. According to 2012 China Discipline Ranking approved by the Chinese Ministry of Education, Communication University of China is ranked 1st in "Journalism and Communication" and "Drama Film and Television", 6th in Art Theory, 9th in Design, 17th in Fine Arts, 23rd in Politics and 32nd in Chinese Language and Literature in China. Wikipedia.

Zhao S.,Communication University of China
Journal of Convergence Information Technology | Year: 2012

This paper proposes a new technique of image digital watermarking-DWT-based Digital Image Watermarking Algorithm Associated with the Transformation of Time Domain. This technique has combined a pre-transformation in time domain with DWT. The effectiveness of the proposed method is testified by simulation experiments using Hadamard matrix, orthogonal matrix, and orthogonal matrix pair. The simulation results show the 8th-order orthogonal matrix pair and 16th-order Hadamard matrix outperform others. Specially, compared with the conventional DWT watermarking method, the presented method is effectively robust against most of the common image processing attack, such as: white Gaussian noise, Gaussian filtering, and compression attack.

Tian S.-H.,Communication University of China
Guangdianzi Jiguang/Journal of Optoelectronics Laser | Year: 2015

A series of single Eu3+ activated NaY(MoO4)2 were synthesized by a solid state reaction at 550 ℃ for 4 h, and their luminescent properties are investigated. Phase formation is determined by X-ray diffraction (XRD) in a Bruker AXS D8 advanced automatic diffractometer (Bruker Co., German) with Ni-filtered Cu Kα1 radiation (λ=0.154 nm). Steady time resolved luminescence spectra, and excitation and emission spectra are detected by a fluorescence spectrophotometer (Hitachi F-4600). Commission International de I'Eclairage (CIE) chromaticity coordinates of samples are measured by a PMS-80 spectra analysis system. The X-ray powder diffraction results show that there has no crystalline phase other than NaY(MoO4)2. NaY(MoO4)2: Eu3+ can create red emission under the 393 nm excitation, and the prominent luminescence in red (616 nm) is due to the 5D0-7F2 transition of Eu3+. The emission intensities of Eu3+ in NaY(MoO4)2 enhance with the increase of the impurity concentration, there is no concentration quenching effect, and the phenomena are proved by the decay curves of Eu3+. Moreover, when tuning the Eu3+ doping content, the CIE chromaticity coordinates of NaY(MoO4)2: Eu3+ are measured, and the corresponding results present that they locate in the red region. The results indicate that the phosphors may have the potential applications in white light emitting diodes. ©, 2015, Board of Optronics Lasers. All right reserved.

Rui H.,Communication University of China
Journal of Convergence Information Technology | Year: 2012

Mobile telecommunications have developed rapidly in China. China has become the most promising mobile phone market in the world. This research estimates the trend of adoption of mobile phones in China using the Bass diffusion model. It is found that the Bass model is suitable for accurate fitting and forecasting the diffusion of mobile phones. The analysis of the diffusion process provides some interesting aspects. The selection of the ultimate potential market is usually conservative. It is appropriate that the ultimate potential market is 80-90% of the total population in China.

Song L.,Communication University of China
IEEE Transactions on Vehicular Technology | Year: 2011

In this paper, we propose a relay selection amplify-and-forward (RS-AF) protocol in general bidirectional relay networks with two sources and N relays. In the proposed scheme, the two sources first simultaneously transmit to all the relays, and then, a single relay with a minimum sum symbol error rate (SER) will be selected to broadcast the received signals back to both sources. To facilitate the selection process, we propose a simple suboptimal minmax criterion for relay selection, where a single relay that minimizes the maximum SER of two source nodes will be selected. Simulation results show that the proposed minmax selection has almost the same performance as the optimal selection with lower complexity. We also present a simple asymptotic SER expression and make a comparison with the conventional all-participate AF relaying scheme. The analytical results are verified through simulations. To improve the system performance, optimal power allocation (OPA) between the sources and the relay is determined based on the asymptotic SER. Simulation results indicate that the proposed RS-AF scheme with OPA yields considerable performance improvement over an equal-power-allocation scheme, particularly with a large number of relay nodes. © 2011 IEEE.

Piao D.,Communication University of China
IEEE Transactions on Wireless Communications | Year: 2013

The eigenvalues and channel capacity of the hexapolarized MIMO system in free-space (FS) and three non-FS scenarios are investigated, based on the exact determinant electromagnetic field expressions. Computation results show that there are generally 6 nonzero eigenvalues in all the four scenarios. However, the values of the eigenvalues are affected strongly by the link distance, the antenna position and the scattering condition, thus some of the eigenvalues are too small to contribute to the overall channel capacity. Interestingly, the smallest two eigenvalues and the corresponding hexapolarized MIMO channel capacity can be increased obviously with the increasing of the number of scattering planes, especially in the far field. Furthermore, more scattering can increase the robustness of the multipolarized MIMO system over the location of the array. However, in those non-FS channels, a threefold increase of the capacity over that in the FS channel is not obtained, and the maximum capacity gain is 2.15. Fortunately, a threefold capacity gain of using the tri-polarized electric dipoles over the one-polarized electric dipole can be obtained in most cases of the three-mirror (3M) channel. Finally, some numerical simulations were conducted, the theoretical predicted hexapolarized MIMO capacities agree well with that obtained from the simulations. © 2002-2012 IEEE.

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