PRIMARY TEACHERS’ CODE-SWITCHING IN EFL CLASSROOMS

Teaching English has never been easy especially for countries where English is a foreign language. It becomes more challenging if the learners are primary students because their English proficiency is low. Therefore, primary teachers are required to have appropriate teaching methods for them. Code-switching is considered one of teaching methods which is adopted by primary teachers frequently in the classroom. It not only assists teachers in teaching but also in classroom management effectively. Thus, research is conducted to find out functions of CS as well as to the reasons why primary English teachers use it in their classroom. This research is qualitative research. The participants of this study are English teachers who are teaching at primary schools in the Mekong Delta. The instruments of this study were observation, audio-recording, and interview. The results showed that CS was actually used a lot by primary English teachers in their classroom. However, code-switching serve their teaching most. Teachers also admitted that it provided great support for them in teaching such as helping students understand the lesson better and saving time. This study is expected to benefit EFL teachers, especially those who are teaching English for primary schools in general and for young learners in particular. Furthermore, it enables primary EFL teachers to have insights into the functions of CS as well as when it is used in teaching practices. In addition, primary EFL teachers are expected to have critical thinking of the CS and make suitable choices in applying CS effectively. Article visualizations

Reactivity of ethylene oxide in contact with contaminants

Ethylene oxide (EO) is a very versatile compound with considerable energy in its ring structure. Its reactions proceed mainly via ring opening and are highly exothermic. Under some conditions, it is known to undergo a variety of reactions, such as isomerization, polymerization, hydrolysis, combustion and decomposition Due to its very reactive characteristic and widely industrial applications, EO has been involved in a number of serious incidents such as Doe Run 1962, Freeport 1974, Deer Park 1988 and Union Carbide Corporation’s Seadrift 1991. The impacts can be severe in terms of death and injury to people, damage to physical property and effects on the environment. For instance, the Union Carbide incident in 1991 caused one fatality and extensive damage to the plant with the property damage of up to 80 million dollars. Contamination has a considerable impact on EO reactivity by accelerating substantially its decomposition and playing a key role on EO incidents. In this work, the reactivity of EO with contaminants such as KOH, NaOH, NH4OH, and EDTA is evaluated. Useful information that is critical to the design and operation of safer chemical plant processes was generated such as safe storage temperatures (onset temperature), maximum temperature, maximum pressure, temperature vs. time, heat and pressure generation rates as a function of temperature and time to maximum rate using adiabatic calorimetry. A special arrangement for the filling-up of the cell was constructed due to the gaseous nature and toxicity of EO. A comparison of their thermal behavior is also presented since several contaminants are studied

Life Cycle Carbon Dioxide Emissions Assessment in the Design Phase: A Case of a Green Building in Vietnam

Buildings are responsible for about 30% of the total CO2 emissions globally. To reduce this amount of CO2, developing green buildings is one of the best approaches. However, this approach is undeveloped in Vietnam due to lacking methods to evaluate design alternatives to meet the criteria of green buildings. This paper presents a life-cycle CO2 analysis (LCCO2A) as a tool to support the decision-making process in the design phase of a 75-year-lifespan green building in Vietnam. The study conducts LCCO2A for two design alternatives (with different bricks usage and glass types) and points out the reasons for the differences. Comparing the first alternative with the second one, the results show slight variations in the amount of CO2 emissions in the erection and demolition phases (with an increase of 21.81 tons and a reduction of 106.1 tons of CO2eq, respectively), and a significant difference in the operation phase (10,631.52 tons of CO2eq or 58.34% reduction). For the whole life-cycle, the second design scenario, which uses “greener” materials shows a great decrease of 10,715.81 tons of CO2eq or 37.54%. By comparing its results with the findings in the literature, this research proves the environmental dominance of green buildings over other building categories

An Analysis of Value Chain in the Vietnam Construction Industry

A value chain in construction industry is implemented to ensure that a construction project is successful from the planning stages, all the way to the completed and approved building. Therefore, it is important to utilize a construction value chain because it ensures that the project delivers the maximum value for the least amount of capital. However, value chain analysis in the construction industry is little understood. The present study aims to analyze the status quo for the construction value chain in Vietnam. The findings indicated that there are three primary parts of the Vietnam construction value chain. The analysis results indicated that there are three primary parts of the Vietnam construction value chain which includes: (1) input factors (i.e., labors, materials, and machines); (2) construction processes (i.e., design, bidding, foundation construction, structural construction, and finishing works); (3) construction markets (i.e., civil construction market, industrial construction, infrastructure construction). The outcomes illustrated a comprehensive picture in the Vietnam construction value chain and build a strong platform to implement better appropriate tasks towards improving sustainable competitive advantages in the construction industry

How to Support Poor Vietnamese Consumers to Deal with Food Price Volatility and Food Safety Issues

With 66 per cent of the population living in rural areas, over half depending on farm activities, food security and food safety are now two sides of the government effort to ensure food accessibility for the poor in Vietnam. While people living on low incomes may have to choose cheaper food over safer food, they are now more aware of food safety issues, and need more support to access safe food. After a long time of focusing on increasing food security in terms of quantities, new efforts are now needed to change the practice and awareness of stakeholders to move to quality?oriented production and consumption, including creating reasonable incentives for food producers, socialising of food safety monitoring and improving food safety inspection in Vietnam

Safety-oriented Resilience Evaluation in Chemical Processes

In the area of process safety, many efforts have focused on studying methods to prevent the transition of the state of the system from a normal state to an upset and/or catastrophic state, but many unexpected changes are unavoidable, and even under good risk management incidents still occur. The aim of this work is to propose the principles and factors that contribute to the resilience of the chemical process, and to develop a systematic approach to evaluate the resilience of chemical processes in design aspects. Based on the analysis of transition of the system states, the top-level factors that contribute to Resilience were developed, including Design, Detection Potential, Emergency Response Planning, Human, and Safety Management. The evaluation framework to identify the Resilience Design Index is developed by means of the multifactor model approach. The research was then focused on developing complete subfactors of the top-level Design factor. The sub-factors include Inherent Safety, Flexibility, and Controllability. The proposed framework to calculate the Inherent Safety index takes into account all the aspects of process safety design via many sub-indices. Indices of Flexibility and Controllability sub-factors were developed from implementations of well-known methodologies in process design and process control, respectively. Then, the top-level Design index was evaluated by combining the indices of the sub-factors with weight factors, which were derived from Analytical Hierarchical Process approach. A case study to compare the resilience levels of two ethylene production designs demonstrated the proposed approaches and gave insights on process resilience of the designs

Material Design for Concrete Using Low-Quality Recycled Aggregate

Since the 19th century, concrete has been a fundamental construction material. It is the most popular manmade material in the world because of its more reliable workability, greater durability, and lower cost compared with other construction materials. However, because of its durability, demolishing or renovating old structures generates a huge amount of concrete waste, which, if not properly treated or reused, can adversely affect the environment. Therefore, the development of concrete-recycling technology is a necessary and pressing requirement for all the countries. This study concerns material design with concrete using low-quality recycled aggregates prepared via an aggregate replacement method. To evaluate the quality of the aggregates in recycled aggregate concrete, experiments were conducted using specimen groups characterized by various mix proportions. Accordingly, when low-quality recycled aggregate is used, by employing the relative quality index method for material design, the manufacturing of recycled aggregate concrete with required performance could be achieved

The effect of intervention on health behaviour and ethical consumption: A cross-national study

ABSTRACT Background To my knowledge, there is very little information on health behaviour and ethical consumption to be studied in Vietnam. Also, the study on the effectiveness of health intervention to the Vietnamese population is limited. Moreover, there is a need to investigate the health behaviour and ethical judgements of consumers across a broad multi-cultural cross-section of the adult population. The present study is designed to address this research need. The health behaviour and ethical consumption are compared for people from a developing country (Vietnam) and a developed country (the UK). Objective The aim of this paper is to implement a study on a sample of Vietnamese participants to examine whether health behaviour changes. Moreover, the purpose of the study will extend to make a comparison of the health lifestyle behaviours of participants from two diverse cultures and economies: citizens residing in Vietnam and citizens residing in the UK. Methods A cross-national survey is conducted among Vietnamese and British population. Data on demographics, ethical consumption, dietary habit and physical activity are collected. The study applies a 2 x 2 experimental design (intervention vs. control) x (baseline vs. follow-up). The between - participants variable is the assignment into either the intervention group or the control group. The within - participants variable is the time in which questionnaires are managed: baseline or 7 days follow-up (i.e. intervention period). The participants are randomly assigned to the intervention or control group. The intervention method to be used is information leaflet which mentions 5 health and lifestyles guidelines. The Mann Whitney u-test is performed with all outcome measures across the control and intervention condition. Correlations of ethical consumption, dietary habit and physical activity are identified using multivariable regression analysis. Results A total of 91 Vietnamese and 30 British completes the baseline questionnaire. The Vietnamese participants are randomly divided into control group (51 participants) and intervention group (40 participants). All the British participants belong to the intervention group. After the intervention period of 7 days, 14 British and 58 Vietnamese complete final questionnaire. Vietnamese spend more money on meat and poultry (p=0.0172), fruit and vegetable (p=0.0034) whereas British spend more money on alcohol (p=0.0008). Vietnamese are more likely than British to have better ethical consumption behaviour (p=0.0404). However, no significant difference is observed in terms of dietary habit and physical activity for the two countries. The designed intervention leaflet does not have influence on health behaviour and ethical consumption for the participants in the study. Nevertheless, more than 80% of participants acknowledge the usefulness of the intervention leaflet and near 50% of participants follow the guidelines occasionally and very frequently. Gender and education are found to have significant impacts on health and ethical consumption behaviour variables. However, there is no correlation of these variables and age and marital status. Conclusions The study provide a valuable basis for the comparison regarding to dietary habit, physical activity and ethical consumption of Vietnam and British. The intervention effect is not found in this study. The association of health and ethical consumption behaviour is observed with gender and education but not with age and marital status

Low-Dose CT Image Denoising using Image Decomposition and Sparse Representation

X-ray computed tomography (CT) is now a widely used imaging modality for numerous medical purposes. The risk of high X-ray radiation may induce genetic, cancerous and other diseases, demanding the development of new image processing methods that are able to enhance the quality of low-dose CT images. However, lowering the radiation dose increases the noise in acquired images and hence affects important diagnostic information. This paper contributes an efficient denoising method for low-dose CT images. A noisy image is decomposed into three component images of low, medium and high frequency bands; noise is mainly presented in the medium and high component images. Then, by exploiting the fact that a small image patch of the noisy image can be approximated by a linear combination of several elements in a given dictionary of noise-free image patches generated from noise-free images taken at nearly the same position with the noisy image, noise in these medium and high component images are effectively eliminated.Specifically, we give new solutions for image decomposition to easily control the filter parameters, for dictionary construction to improve the effectiveness and reduce the running-time. Instead of using a large dataset of patches, only a structured small part of patches extracted from the raw data is used to form a dictionary, to be used in sparse coding. In addition, we illustrate the effectiveness of the proposed method in preserving image details which are subtle but clinically important. Experimental results conducted on both synthetic and real noise data demonstrate that the proposed method is competitive with the state-of-the-art methods

An adaptive hierarchical sliding mode controller for autonomous underwater vehicles

The paper addresses a problem of efficiently controlling an autonomous underwater vehicle (AUV), where its typical underactuated model is considered. Due to critical uncertainties and nonlinearities in the system caused by unavoidable external disturbances such as ocean currents when it operates, it is paramount to robustly maintain motions of the vehicle over time as expected. Therefore, it is proposed to employ the hierarchical sliding mode control technique to design the closed-loop control scheme for the device. However, exactly determining parameters of the AUV control system is impractical since its nonlinearities and external disturbances can vary those parameters over time. Thus, it is proposed to exploit neural networks to develop an adaptive learning mechanism that allows the system to learn its parameters adaptively. More importantly, stability of the AUV system controlled by the proposed approach is theoretically proved to be guaranteed by the use of the Lyapunov theory. Effectiveness of the proposed control scheme was verified by the experiments implemented in a synthetic environment, where the obtained results are highly promising. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Linh Nguyen" is provided in this record*