83 research outputs found

    Language attitudes of Vietnamese undergraduates towards English: an investigation at school of advanced studies of Ho Chi Minh City Open University

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    The investigation reported in this paper is carried out with 444 undergraduates enrolled in the first semester of academic year 2014-2015, which seeks to examine language attitudes towards English language achievement and formation of ethnic identity of Vietnamese undergraduates at Ho Chi Minh City Open University (HCMCOU). The investigation surveys this topic by discussing the study of language attitudes, effects of language attitudes on language achievement, English in Vietnam and awareness of Vietnamese ethnic identity and issues about the relationship between language attitudes and language achievement. The questionnaire survey is conducted to examine students’ language attitudes, which is adapted from Axler et al. (1998) as cited in Liu & Zhao (2011). The results show that students hold positive attitudes towards English and are extrinsically and intrinsically motivated to learn English. They show their sense of Vietnamese patriotism in preserving linguistic and cultural identity on account of nearly 60 percent of wishing to learn Vietnamese well. Concurrently, they illustrate their appreciation of English status in light of 40 percent showing their preference to learn good English first

    YOUTH EDUCATION AND ORIENTATION TOWARD HO CHI MINH'S IDEOLOGY IN THE CONTEMPORARY CONTEXT

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    During his time, Former President Ho Chi Minh had consistently emphasized the central role, position, and competence of the young generation in realizing the Party and the people's revolutionary path. He believed, “The youth are the future owners of the home country. Indeed, the vitality of the home country, whether it is prosperous or wilting, depends largely on the youth.” Before passing, his words had become the guiding principle for leaders of the Communist Party of Vietnam, “Nurturing future revolutionary generations is of utmost importance and necessity.” Especially, given that the functioning of the current market economy has revealed its multiple drawbacks, it is salient to educate and orient the youth following Ho Chi Minh's ideology to produce a young generation that is moral in ethics and efficient in labour.  Article visualizations

    Performance of free-space QKD systems using SIM/BPSK and dual-threshold/direct-detection

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    This paper proposes a novel free-space quantum key distribution (QKD) system using subcarrier intensity-modulation (SIM) binary phase-shift-keying (BPSK) and dual-threshold/direct-detection (DT/DD) receiver with an avalanche photodiode (APD). The proposed system enables the adoption of well-developed analytical models in conventional free-space optical (FSO) communications and achieves the QKD function with a simple configuration. We analytically investigate the design criteria for transmitter and receiver, in particular, the modulation depth and the setting for dual-threshold in the context of security requirement of QKD systems. The quantum bit error rate (QBER) and the ergodic secret-key rate of the proposed system are analytically derived in closed-form expressions, considering the channel loss, atmospheric turbulence modeled by the log-normal distribution, and receiver noises. Monte-Carlo (M-C) simulations are also implemented to validate the analytical results, and numerical results confirm the feasibility of the proposed system

    Halliday\u27s Functional Grammar: Philosophical Foundation and Epistemology

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    It is difficult to track the philosophy foundation and epistemology of systemic functional grammar (SFG) formulated by Halliday in the 1980s as this kind of grammar views language as a systemic resource for meaning. Besides, it has had global impacts on linguistics and flourished in contemporary linguistic theory. Anyone who is familiar with Halliday\u27s work realizes that his SFG is an approach designed to analyze English texts. Halliday (1994: xv) explicitly states that “to construct a grammar for purposes of text analysis: one that would make it possible to say sensible and useful things about any text, spoken or written, in modern English.” The aim of this study is not about the applicability of SFG to text analysis as many researchers and scholars do. Our efforts are made to clarify the philosophical foundation of Halliday\u27s SFG. The paper presents on triangle: (i) language, mind and world; (ii) and empiricism in Halliday\u27s SFG

    AGING OF WATERBORNE PAINT BASED ON THE ACRYLIC RESIN EMULSION AND ORGANIC PIGMENT

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    Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl have been investigated by general appearance assessment, adhesion change, FT-IR and discoloration. The obtained results showed that the both of paint-formulas coatings had no cracks, blisters, flacks and there was no change of adhesion during the aging process. However, IR analysis indicated that there were some changes in chemical structures of coating with and without Green Luconyl during aging process. To specify, IR spectrums of initial and aged coating no containing Green Luconyl illustrated aging process led content of O-H and C=C increased significantly but baseline of spectra was fairly unchanged. For coating filled Green Luconyl, IR spectrums’ shape was fairly stable but baseline saw a clear reduce during accelerated weather exposure. Moreover, SEM images indicated that surfaces morphology of samples changed differently depending on in presence of organic pigment. Surface of aged coating without Luconyl saw rougher than surface of coating with Luconyl after aging process. Hence, the weather aging test had more significant influence on paint coating in absence of Luconyl than paint coating in presence of Luconyl. It was explained that the macroradical produced in aging process would attack into conjugated double bonds of Luconyl instead of double bonds of AC-261 leading to aged coating filled Luconyl become more opaque than initial while coating no filled Luconyl had significant changes in chemical structure during aging process. Although this was a hypothesis, it saw a suitable with the obtained results. The paint coating in presence of Luconyl illustrated significant color change, especially, showed the loss of green color while the other paint coating showed slight color change

    Angular rate sensing by circulatory vortex flow: design, simulation and experiment

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    A fully packaged convective vortex gyrometer actuated by a PZT diaphragm is reported. The flow circulates at higher velocity after each actuating circle to form a vortex in the desired chamber. The vortex is characterized by hotwire anemometry. The device is initially designed based on a numerical analysis whose results are used to set up the experiment. The angular rate sensing of the device is successfully tested using a turntable. The technique is a potential solution to various applications related to inertial sensing and fluidic amplifier

    ASSESSMENT OF GEOMORPHIC PROCESSES AND ACTIVE TECTONICS IN CON VOI MOUNTAIN RANGE AREA (NORTHERN VIETNAM) USING THE HYPSOMETRIC CURVE ANALYSIS METHOD

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    the Day Nui Con Voi (DNCV) area of Vietnam. For this purpose, a spatial database was collected and constructed, including DEM (Digital Elevation Model) and a geological map. The hypsometric curve (HC) analysis method and its statistical moments were adopted to use for the assessment. These methods have been widely used for the assessment of geomorphic processes and active tectonics in many areas in the world showing promising results. A total of 44 sub-basins of the Red River and the Chay river were analyzed. The result shows that 3 curve-types such as "straight- shape", "S- shape", and concave were found; with the concave curve being the dominant and widely distributed in the northeast side and in the south of the southwestern side of the study area. The hypsometric integral (HI) values are rather small with the largest value is 0.37 and the smallest one is 0.128. Other statistical moments of the hypsometric curve, i.e. skew (SK), kurtosis (KUR), and the density function (density skew - DSK and density kurtosis-DKUR) show great values, which increased in the south direction of the area study. Accordingly, recent active tectonics (uplift-lower) in the study area is generally weak; however, they are also not completely homogeneous and can be distinguished by different levels. The southwestern side is being lifted higher than the northeastern side. The northern part is being lifted larger than the southern part. In the region, the uplift activities were increased gradually in the Pliocene-Quaternary and could have stopped at certain time in the past. The current geomorphic processes are mainly headward erosion in the upstream.References Allen, C.R., Gillepie, A.R., Han, Y., Sieh, K.E., Zhu, C., 1984. 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    Intersatellite-link demonstration mission between CubeSOTA (LEO CubeSat) and ETS9-HICALI (GEO satellite)

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    LEO-to-GEO intersatellite links using laser communications bring important benefits to greatly enhance applications such as downloading big amounts of data from LEO satellites by using the GEO satellite as a relay. By using this strategy, the total availability of the LEO satellite increases from less than 1% if the data is downloaded directly to the ground up to about 60% if the data is relayed through GEO. The main drawback of using a GEO relay is that link budget is much more difficult to close due to the much larger distance. However, this can be partially compensated by transmitting at a lower data rate, and still benefiting from the much-higher link availability when compared to LEO-to-ground downlinks, which additionally are more limited by the clouds than the relay option. After carrying out a feasibility study, NICT and the University of Tokyo started preparing a mission to demonstrate the technologies needed to perform these challenging lasercom links. Furthermore, to demonstrate the feasibility of this technique, an extremely-small satellite, i.e. a 6U CubeSat, will be used to achieve data rates as high as 10 Gbit/s between LEO and GEO. Some of the biggest challenges of this mission are the extremely low size, weight and power available in the CubeSat, the accurate pointing precision required for the lasercom link, and the difficulties of closing the link at such a high speed as 10 Gbit/s.Comment: 5 pages, 10 figures, 3 table
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