Molecular Kondo effect in flat-band lattices

The Kondo effect of a single magnetic impurity embedded in the Lieb lattice is studied by the numerical renormalization group. When the band flatness is present in the local density of states, it quenches the participation of all dispersive electrons in the Kondo singlet formation, and reduces the many-body Kondo problem to a two-electron molecular Kondo problem. The two-electron analog of the many-body Kondo singlet, a quantum entanglement of two spins, is stable at low temperature, and the impurity contributions to thermodynamical and dynamical quantities are qualitatively different from that obtained in the conventional Kondo effect in systems without flat bands. The existence conditions of the molecular Kondo effect in narrow band systems are also discussed

THE RELATIONSHIP BETWEEN LEARNING STRATEGY USE IN ENGLISH AND MOTIVATION OF STUDENTS AT A COLLEAGUE IN CAN THO CITY, VIETNAM

Among the many factors that increase students’ achievement in the mastery of foreign languages, including English, are motivation and use of language learning strategies. Previous studies by a range of researchers have identified these two elements as the most important in obtaining success in language learning. This study carried out on 152 university students, roughly equal in gender, studying at a university in Can Tho, Vietnam, sought to discover the relationships between these two factors within the Vietnamese language learning context. In particular, the study sought to 1) discover which of two types of motivation, intrinsic and extrinsic, is most prevalent among the students studied; 2) their use of language learning strategies; 3) reveals the relationship between students' motivation and use of language learning strategies; and 4) describe the differences in their use of language learning strategies based on whether their motivation was high, medium or low. Research instruments included Schmidt et al.'s Questionnaire on Motivation in Learning English, and Oxford's Strategy Inventory for Language Learning (both modified for the Vietnamese language learning context and translated into Vietnamese), plus an interview with 18 of the students to gain greater insight into the answers they gave on the questionnaires. Results were obtained using standard deviations and t-tests. They showed that Vietnamese university students are mainly extrinsically motivated; that all strategies were used at least at a medium level, amidst other fluctuations; and that those metacognitive strategies are most prevalent among medium and high motivated students but affective strategies are most common among low motivation students. Recommendations flowing from these results are that teachers should prioritize the formal teaching of learning strategies and should attempt to increase intrinsic motivation by putting greater emphasis on making language learning fun and relevant to the students' interests and passions. Article visualizations

SOME COMMON ERRORS IN ENGLISH SPEAKING CLASS OF ENGLISH MAJORED FRESHMEN AT TAY DO UNIVERSITY, VIETNAM

In the 21st century, speaking is considered to be one of the most important skills for language learners. However, it is so difficult for students to master this skill. It is so difficult for students to master this skill because they encounter in some common mistakes when speaking in class. Therefore, the purpose of this research aimed at finding out common errors in English speaking class of English majored freshmen at Tay Do University. Specifically, this study is done to figure out whether English majored freshmen at Tay Do University encounter regularly with some mistakes while speaking English in class. In this study, a questionnaire embraced 28 questions, including questions and statements which were used as the main instruments to collect the data. The participants in this study were 91 English majored freshmen in the 3 classes of English 14A, 14B, 14C at Tay Do University. The results of the study pointed out that the English-majored freshmen had some common errors and difficulties with vocabulary, pronunciation, psychology in English speaking class. It is hoped that this research can be helpful for both the English-majored freshmen and other non-majored English students at Tay Do University to realize their common errors in the process of improving and developing their speaking skill. Article visualizations

Effects of Mannan Oligosaccharide (MOS) on the Survival, Physiological, and Immunological Response of the Black Tiger Prawn (Penaeus monodon Fabricius, 1798) when Challenged with two Different Stressors

Two trials were conducted to determine the effects of mannan oligosaccharide (MOS) on the resistance of the black tiger prawn (Penaeus monodon) to two different stressors, bacterial infection by Vibrio alginolyticus, and the environmental pollutant ammonia (NH3). Prawns were fed two different diets, 0% (control diet) and 0.15% MOS, for 8 weeks prior to exposure to the stressors. They were then tested for survival, physiological, and immunological parameters, as indicators of health status. When the two groups were exposed to NH3 and bacterial infection, survival of prawns fed the MOS diet was significantly higher (P<0.05) than prawns fed the control diet. Similarly, the wet hepatosomatic index (Hiw), dry hepatosomatic index (Hid), hepatopancreatic moisture content (HM), total hemocyte count (THC), and granular cell percentage (GC%), of the MOS fed prawns was significantly higher (P<0.05) than in prawns fed the control diet. Bacteremia of the MOS fed prawns was lower (P<0.05) than the control diet-fed prawns after bacterial infection. Findings demonstrated the potential of MOS to improve the survival, health status, and immunity of black tiger prawns when challenged with bacterial infection and NH3 exposure

Online Load Balancing for Network Functions Virtualization

Network Functions Virtualization (NFV) aims to support service providers to deploy various services in a more agile and cost-effective way. However, the softwarization and cloudification of network functions can result in severe congestion and low network performance. In this paper, we propose a solution to address this issue. We analyze and solve the online load balancing problem using multipath routing in NFV to optimize network performance in response to the dynamic changes of user demands. In particular, we first formulate the optimization problem of load balancing as a mixed integer linear program for achieving the optimal solution. We then develop the ORBIT algorithm that solves the online load balancing problem. The performance guarantee of ORBIT is analytically proved in comparison with the optimal offline solution. The experiment results on real-world datasets show that ORBIT performs very well for distributing traffic of each service demand across multipaths without knowledge of future demands, especially under high-load conditions

EFL STUDENT’S PROBLEMS WITH PARAGRAPH WRITING AT TAY DO UNIVERSITY, VIETNAM

This paper studied problems in EFL students’ paragraph writing. The research participants were first-year students of English in Tay Do University (TDU). To achieve the desired aims of the current study, the researcher combined both qualitative and quantitative methods, using questionnaires, interviews, and observations as the main instruments. The researcher used the package of social sciences (SPSS) for analysis. Research results showed that the freshmen at TDU often encountered problems in writing paragraphs. These accounted for grammatical structures, vocabulary, and coherence. Basing on the research results, students could recognize their difficulties when writing and find some new ways to overcome them. It is suggested that teachers should find and update some new teaching methods so as to develop students’ paragraph writing skills. Article visualizations

Acquisition of request modifiers in Vietnamese as a second language

This study examines the acquisition of request modifiers by learners of L2 Vietnamese, with a view to expanding the range of target languages under inquiry and contributing to the field of L2 pragmatics acquisition. Data were collected from nine Vietnamese native speakers and 18 learners from various language backgrounds, using open role-plays in six scenarios with differing social power and imposition levels. An analysis was made of the learners' use of request modifiers in relation to their proficiency levels in Vietnamese and their lengths of residency in the target language environment. Findings supported claims in the literature that learning pragmatics is particularly challenging for low-proficiency learners, and provided some evidence of pragmatic development in the case of highproficiency learners who had stayed in the target language culture for an extended period

Impact of Foreign Direct Investment on Economic Restructuring in Bac Ninh

In recent years, foreign direct investment (FDI) has played an important role in Bac Ninh’s economic restructuring. Of all provinces, Bac Ninh has always been leading the way for attracting foreign investment in Vietnam. The goal of this article is to study the relationship between FDI and the structure of economy of Bac Ninh. We use Ordinary Least Squares regression (OLS) to analyze the influence of the province’s FDI on its economic restructuring over the period from 2009 to 2019. The result partly shows that the FDI has had a strong impact on Bac Ninh’s economic restructuring in both speed and quality. Through these findings, we propose several recommendations for the local authorities to continue to attract the FDI and reinforce the positive impacts of the FDI on the province’s economic restructuring in the future. Keywords: Bac Ninh, foreign direct investment (FDI), economic restructuring, OLS DOI: 10.7176/EJBM/12-15-03 Publication date:May 31st 202

Self-injurious Behavior of Children with Autism in Vietnam: Across Sectional Study

This study explored self-injurious behaviour (SIB) of autistic children in Vietnam through a crosssectional design. 60 informants, including 57 parents and 3 caregivers completed the questionnaire on problem behaviour consisting of aggression, self-injury, stereotyping, property destruction, other problem behaviours and their functions. Results revealed that children experienced all mentioned problem behaviours, especially self-injurious behaviour. The topographies of self-injurious behaviour of the children included head-hitting, head-scratching, head-banging, hair-pulling, face-hitting, facepuncturing with a pen, ear-scratching, lip-picking, hand-biting, hand-scratching, hand-pinching, and belly-scratching. The most common area of self-injurious behaviour is the head. The functions of these problem behaviours were expressed in four types (social positive reinforcement, social negative reinforcement, automatic positive reinforcement and automatic negative reinforcement). Social positive reinforcement appeared as a prominent function. Out of these 57 children, 21 of them who were autistic with self-injurious behaviour went through a functional behaviour assessment (FBA) in which the four conditions known as attention, tangible items, escape from task/activities, automatic stimulation were tested. The results of functional behaviour assessment (FBA) further indicated the correspondence between the FAST-R and FBA outcome on function of problem behaviour, especially self-injurious behaviour. The research concluded that the prominent function of these self-injurious behaviours was social function. It means self-injurious behaviours usually occur within a condition of social interaction, especially, in this present study, in the tangible condition. The antecedent of selfinjurious behaviour is the removal of tangibles (e.g. food, preferred items). This paper contributes to our knowledge of self-injurious behaviour of children with autism in Vietnam where empirical research of this field was still very rare