4,775 research outputs found

    Performance gap of two users in downlink full-duplex cooperative NOMA

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    A full-duplex non-orthogonal multiple access (FD-NOMA) systems are expected to play a significant role in fifth generation (5G) networks, addressing spectrum efficiency and massive connections. In this regard, the feasibility of FD communications to improve spectrum utilization is main consideration in term of outage performance. Specifically, we derive exact formulas of outage probability for FD-NOMA, over Nakagami-m fading channels. Extensive analysis revealed that higher quality of channel leads to better performance. We verify expressions throughout Monte-Carlo simulations

    Exact Outage Performance Analysis of Amplify-and-forward-aware Cooperative NOMA

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    In this paper, new radio access scheme that combines Amplify-and-Forward (AF) relaying protocol and non-orthogonal multiple access (NOMA) system is introduced. In particular, different scenarios for fixed power allocation scheme is investigated. In addition, the outage probability of both weak and strong user is derived and provided in closed-form expressions. Such outage is investigated in high SNR scenario and comparison performance between these NOMA scenarios is introduced. Numerical simulations are offered to clarify the outage performance of the considered scheme if varying several parameters in the existing schemes to verify the derived formulas

    Numerical Simulations of Flows over a Forced Oscillating Cylinder

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    A numerical study of incompressible laminar flow past a circular cylinder forced to oscillate longitudinally, transversely and at an angle to the uniform freestream is performed using the dynamic mesh method. The simulations are conducted at a fixed Reynolds number of 80 with amplitude ratios varying between 0.14 to 0.50 and excitation frequency ratios of 0.05 to 3.0. Good agreement to previous experimental and numerical investigations is achieved in the prediction of the lock-on range, force amplifications and vortex shedding modes for longitudinal and transverse oscillations. For excitations at an angle of 60 degrees relative to the oncoming flow, previously identified modes of AI and, AII were successfully predicted. In addition, at higher amplitude ratios the entire synchronised von Karman wake street displayed a deviating effect from the centreline. Analysis of the wake response via phase plane diagrams and the transverse force coefficients revealed two lock-on regions. The extents of these lock-on regions, and the variation of the forces and near wake vortex shedding modes are presented and discussed herein

    A Combination of Finite Difference and Finite Element Methods for Temperature and Stress Predictions of Early-Age Concrete Members

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    A combination of finite difference and finite element methods was employed to develop a model for predicting the temperature development and thermally induced stresses in early-age concrete members (such as bridge footings, piers, columns, girders, and slabs). A two-dimensional finite difference (FD) scheme was utilized for heat generation and transfer within a hydrating concrete member. A finite element (FE) plane strain model was then established to compute the thermal stresses in the concrete subjected to the temperature changes. The FD-FE model can be easily created using any programing language, and the methodology can be used to predict the temperatures and stresses as well as assess the possibility of early-age cracking in concrete members

    Cooperative underlay cognitive radio assisted NOMA: secondary network improvement and outage performance

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    In this paper, a downlink scenario of a non-orthogonal multiple access (NOMA) scheme with power constraint via spectrum sensing is considered. Such network provides improved outage performance and new scheme of NOMA-based cognitive radio (CR-NOMA) network are introduced. The different power allocation factors are examined subject to performance gap among these secondary NOMA users. To evaluate system performance, the exact outage probability expressions of secondary users are derived. Finally, the dissimilar performance problem in term of secondary users is illustrated via simulation, in which a power allocation scheme and the threshold rates are considered as main impacts of varying system performance. The simulation results show that the performance of CR-NOMA network can be improved significantly

    Uma pesquisa-ação de 3 anos em uma universidade vietnamita: Alunos como cogeradores de conteúdo das aulas

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    In the context of the 4th Industrial Revolution with unlimited technological advancement and innovation, how can educators innovate their teaching and facilitate their students in their learning process, so that students can accumulate required skills and achieve the set learning outcomes of each course they take? In order to find out the answer, the authors have revised some literature concerning BYOD trend, active learning strategies, flipped classroom and learner-generated content as the theoretical base for their study. Action research has been conducted at a Vietnamese university with the participation of English-majored students in Theory of English Translation and Interpreting classes from 3 different intakes. The findings include students’ positive perception towards the content-generation practices. Some achievements and challenges in the teaching and learning process have also been reported. This paper also recommends further studies so that the practice could be utilized to the best outcomes.En el contexto de la Cuarta Revolución Industrial con un avance tecnológico e innovación ilimitados, ¿cómo pueden los educadores innovar su enseñanza y facilitar a sus estudiantes su proceso de aprendizaje, para que los estudiantes puedan acumular las habilidades requeridas y lograr los resultados de aprendizaje establecidos en cada curso que toman? Para encontrar la respuesta, los autores han revisado cierta literatura sobre la tendencia BYOD, las estrategias de aprendizaje activo, el aula invertida y el contenido generado por el alumno como base teórica para su estudio. Se llevó a cabo una investigación de acción en una universidad vietnamita con la participación de estudiantes con especialización en inglés en clases de Teoría de la traducción e interpretación en inglés de 3 tomas diferentes. Los hallazgos incluyen la percepción positiva de los estudiantes hacia las prácticas de generación de contenidos. También se reportan algunos logros y desafíos en el proceso de enseñanza y aprendizaje. Este documento también recomienda más estudios para que la práctica pueda utilizarse con los mejores resultados.No contexto da 4ª Revolução Industrial, com avanço tecnológico e inovação ilimitados, como os educadores podem inovar seu ensino e facilitar seus alunos em seu processo de aprendizagem, para que os alunos possam acumular as habilidades necessárias e alcançar os resultados de aprendizagem definidos de cada curso que fazem? Para encontrar a resposta, os autores revisaram alguma literatura sobre a tendência BYOD, estratégias de aprendizagem ativa, sala de aula invertida e conteúdo gerado pelo aluno como base teórica para seu estudo. Uma pesquisa-ação foi realizada em uma universidade vietnamita com a participação de alunos formados em inglês nas aulas de Teoria da Tradução e Interpretação do Inglês de 3 diferentes entradas. Os resultados incluem a percepção positiva dos alunos em relação às práticas de geração de conteúdo. Algumas conquistas e desafios no processo de ensino e aprendizagem também foram relatados. Este artigo também recomenda mais estudos para que a prática possa ser utilizada para os melhores resultados

    SITUATION OF THE TEACHING PHYSICAL EDUCATION FOR SEVENTH GRADERS IN THAI NGUYEN CITY FROM THE PERSPECTIVE OF DIVISION IN EDUCATION

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    Differentiation-oriented physical education (PE) helps learners participate in learning activities with content and forms suitable to their personal characteristics. Through researching documents, interviews, and pedagogical observations, the project explores the current status of teaching physical education to 7th graders in Thai Nguyen City from the perspective of division in education. The results of this research are an important practical basis to propose measures to organize teaching physical education in a differentiated direction for 7th graders in Thai Nguyen City.  Article visualizations

    Professional development for ESL lecturers – a struggle to integrate ICT into teaching

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    Information and Communications Technology (ICT) plays a crucial role in our daily life. In fact, students are considered digital citizens and have become accustomed to being always connected to their devices and the Internet. Given the importance ICT plays in our lives, education institutions nowadays have a duty to incorporate ICT into teaching and learning in order to better prepare students for 21st Century skills and careers. Although certain technological equipment may be available in classrooms, there are several external and internal factors that affect the proper implementation of ICT in classrooms. In preparing students to be career-ready, ICT integration is imperative. This paper will discuss factors affecting ESL lecturers’ professional development in terms of ICT application in the classroom. A total of 61 lecturers from 12 non-English-majored universities in Vietnam voluntarily completed this quantitative study’s survey questionnaire. The findings show that although ESL lecturers are aware of the significance of some factors affecting ICT implementation in classrooms, they are struggling to learn, to adapt, and to integrate ICT into their classrooms
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