Zhou Nanrun

Quantum Secure Direct Communication Using Entangled Photon Pairs and Local Measurement

We present a scheme for quantum secure direct communication, in which the message is encoded by local unitary operations, transmitted through entangled photons, and deduced from both the sender and receivers local measurement results. In such a scheme, only one pair of entangled photons is consumed, and there is no need to transmit the senders qubit carrying the secret message in a public channel, in order to transmit two-bit classical information.

Semantic Web Service Selection Based on Context and QoS

Because of lacking context and Quality of Service (QoS) attributes, the result of service selection mostly does not fulfill user’s contextual expectation and individual requirements when we apply traditional semantic Web service selection method. An approach for semantic Web service selection based on context and QoS is proposed in the paper. Firstly, the contextual ontology and QoS ontology is built. Secondly, the corresponding service selection models are proposed. Finally, an algorithm of semantic web service selection based on context and QoS is proposed. Compared with existing approaches for semantic Web service selection, it is proved by the experiment that the result of selection will be more accurate and meet individual requirements. The experiment also proves the validity and feasibility of the algorithm.

Audio-visual underdetermined blind source separation algorithm based on Gaussian potential function

Most existing algorithms for the underdetermined blind source separation (UBSS) problem are two-stage algorithm, i.e., mixing parameters estimation and sources estimation. In the mixing parameters estimation, the previously proposed traditional clustering algorithms are sensitive to the initializations of the mixing parameters. To reduce the sensitiveness to the initialization, we propose a new algorithm for the UBSS problem based on anechoic speech mixtures by employing the visual information, i.e., the interaural time difference (ITD) and the interaural level difference (ILD), as the initializations of the mixing parameters. In our algorithm, the video signals are utilized to estimate the distances between microphones and sources, and then the estimations of the ITD and ILD can be obtained. With the sparsity assumption in the time-frequency domain, the Gaussian potential function algorithm is utilized to estimate the mixing parameters by using the ITDs and ILDs as the initializations of the mixing parameters. And the time-frequency masking is used to recover the sources by evaluating the various ITDs and ILDs. Experimental results demonstrate the competitive performance of the proposed algorithm compared with the baseline algorithms.

Parseval Theory of Complex Wavelet Transform for Wavelet Family Including Rotational Parameters

A rotational parameter Rθ has been introduced to complex wavelet transform (CWT). The rotational CWT (RCWT) corresponds to a matrix element ψ|U2(θ;μ;k)|F in the context of quantum mechanics, where U2(θ;μ;k) is a two-mode rotational displacing-squeezing operator in the η| representation. Based on this, the Parseval theorem and the inversion formula of RCWT have been proved. The concise proof not only manifestly shows the merit of Diracs representation theory but also leads to a new orthogonal property of complex mother wavelets in parameter space.

Teleportation of Squeezed Entangled State

Based on the coherent entangled state |α,x we introduce the squeezed entangled state (SES). Then we propose a teleportation protocol for the SES by using Einstein–Podolsky–Rosen entangled state |η as a quantum channel. The calculation is greatly simplified by virtue of the Schmidt decompositions of both |α,x and |η. Any bipartite states that can be expanded in terms of |α,x may be teleported in this way due to the completeness of |α,x.

Calculation of Gaussian Perturbation on Two Harmonic Oscillators by Virtue of Entangled State Representation

The exact expressions of Gaussian-perturbation matrix elements in one- and two-mode Fock states are derived by virtue of the technique of integration within an ordered product of operators and the entangled state representation. It turns out that the matrix elements are just related to Gegenbauer polynomial and Hypergeometric function respectively. The 1st- and 2nd-order corrections to the energy levels and the 1st-order correction to wavefunctions of harmonic oscillator are deduced.