Learner’s Dialect Use by EFL Instructors: A Study of Junior High School Teachers in a Minority Area of China

The use of learners’ L1 (first language) in the EFL classroom has been widely discussed in the literature. However, the use of local dialects has received less attention. Thus, this study investigates the use of Enshi dialect in EFL classroom in junior high schools in order to explore how teachers deploy the learners’ own dialect in EFL classroom and its effect. The Enshi dialect which is a variant of Mandarin is frequently used in daily life in Enshi Tujia and Miao Autonomous Prefecture. Semi-structured interviews are conducted with 15 teachers who adopt Enshi dialect in EFL classroom teaching in junior high schools in 8 minority villages in Enshi. The results indicate that occasional dialect use does exist in EFL classroom teaching for junior high school students in ethnic minority areas. In addition, four main benefits are revealed when learners use dialects in EFL classes. Teaching English by using dialect helps students to improve the mastery of English grammar, distinguish pronunciation, understand the meaning of English words, phrases and sentences, and enliven the classroom atmosphere. The research also shows that the effective use of learners’ dialects in the EFL classroom plays positive roles in English learning

Decoy State Quantum Key Distribution With Modified Coherent State

To beat PNS attack, decoy state quantum key distribution (QKD) based on coherent state has been studied widely. We present a decoy state QKD protocol with modified coherent state (MCS). By destruction quantum interference, MCS with fewer multi-photon events can be get, which may improve key bit rate and security distance of QKD. Through numerical simulation, we show about 2-dB increment on security distance for BB84 protocol.Comment: 4 pages, 4 figure

STAR-RIS-Assisted-Full-Duplex Jamming Design for Secure Wireless Communications System

Physical layer security (PLS) technologies are expected to play an important role in the next-generation wireless networks, by providing secure communication to protect critical and sensitive information from illegitimate devices. In this paper, we propose a novel secure communication scheme where the legitimate receiver use full-duplex (FD) technology to transmit jamming signals with the assistance of simultaneous transmitting and reflecting reconfigurable intelligent surface (STARRIS) which can operate under the energy splitting (ES) model and the mode switching (MS) model, to interfere with the undesired reception by the eavesdropper. We aim to maximize the secrecy capacity by jointly optimizing the FD beamforming vectors, amplitudes and phase shift coefficients for the ESRIS, and mode selection and phase shift coefficients for the MS-RIS. With above optimization, the proposed scheme can concentrate the jamming signals on the eavesdropper while simultaneously eliminating the self-interference (SI) in the desired receiver. To tackle the coupling effect of multiple variables, we propose an alternating optimization algorithm to solve the problem iteratively. Furthermore, we handle the non-convexity of the problem by the the successive convex approximation (SCA) scheme for the beamforming optimizations, amplitudes and phase shifts optimizations for the ES-RIS, as well as the phase shifts optimizations for the MS-RIS. In addition, we adopt a semi-definite relaxation (SDR) and Gaussian randomization process to overcome the difficulty introduced by the binary nature of mode optimization of the MS-RIS. Simulation results validate the performance of our proposed schemes as well as the efficacy of adapting both two types of STAR-RISs in enhancing secure communications when compared to the traditional selfinterference cancellation technology.Comment: 12 pages, 7 figure