Designing learning activities to develop self-directed learning competency in teaching informatics

Currently, there are not many studies on teaching informatics in the direction of developing students’ self-directed learning (SDL) competency. The results of the survey with 235 informatics teachers in 42 provinces/cities across Vietnam showed that although they are very interested in teaching SDL, teachers are still confused about teaching methods and assessments. To improve the effectiveness of informatics teaching as well as develop SDL for students, the study proposed a method of teaching informatics in the direction of designing activities to guide students to create digital products by themselves. The pedagogical experiment on assessing SDL and learning outcomes was conducted on two experimental and control groups, selected from 87 10th grade students, in the first semester of the school year 2022-2023 at Cam Giang High school in Hai Duong, Vietnam. The results of SDL and test scores of the experimental class were higher than that of the control class (with p-value <0.005– this difference is statistically significant). This proves that the method (creating of digital products) is effective, positively affecting students’ learning, helping students develop SDL competency

On The Performance Of 1-Bit ADC In Massive MIMO Communication Systems

Massive multiple-input multiple-output (MIMO) with low-resolution analog-to-digital converters is a rational solution to deal with hardware costs and accomplish optimal energy efficiency. In particular, utilizing 1-bit ADCs is one of the best choices for massive MIMO systems. This paper investigates the performance of the 1-bit ADC in the wireless coded communication systems where the robust channel coding, protograph low-density parity-check code (LDPC), is employed. The investigation reveals that the performance of the conventional 1-bit ADC with the truncation limit of 3-sigma is severely destroyed by the quantization distortion even when the number of antennas increases to 100. The optimized 1-bit ADC, though having substantial performance gain over the conventional one, is also affected by the quantization distortion at high coding rates and low MIMO configurations. Importantly, the investigation results suggest that the protograph LDPC codes should be re-designed to combat the negative effect of the quantization distortion of the 1-bit ADC

The impact of oil prices, real effective exchange rate and inflation on economic activity: Novel evidence for Vietnam

The goal of this paper is to examine the impact of oil prices on Vietnam's economic activity using vector autoregressive (VAR) modeling and cointegration techniques. We use monthly data for the period 1995-2009 and include inflation and the real effective exchange rate as additional determinants of economic activity. We find evidence of a long-run relationship between oil prices, inflation, exchange rate, and economic activity. The results suggest that both oil prices and the real effective exchange rates have strongly significant impact on economic activity. An increase in oil price or depreciation may enhance economic activity. Vietnamese economic activity is influenced more by changes of value of Vietnamese currency than the fluctuations of oil prices. Inflation has a positive impact on economic activity however its impact is not highly significant. This suggests that moderate inflation is helpful rather than harmful to economic activity.Oil price, Economic activity, Vietnam

Selection of suitable fragment from rbcL gene for DNA barcode analysis of family Halymeniaceae, Rhodophyta

Among the members of Halymeniaceae family, Grateloupia sensu lato occupies the largest composition in species. Classification based on morphological traits is difficult due to the highly variable terete to blade-like thalli among the members of this genus that usually leads to misidentification. Molecular systematics has been applied to classify Grateloupia sensu lato so that the taxonomists acquire a better understanding of the species diversity in general. The plastid gene encoding the large subunit of ribulose-1,5-bisphosphate-carboxylase-oxygenase (rbcL) was the focus of numerous marine algal studies concerning phylogeny and molecular evolution. However, using the full length of rbcL showed disadvantages such as cost and time consuming due to two times of sequencing and two times of PCR. In the present study, the shorter sequence, fragment 773 bp at 5’ end and fragment 579 bp at 3’ end of rbcL were applied and compared for the phylogenetic analysis of Halymeniaceae members. The results indicated there are no differences of topological phylogenetic trees, species resolution within genus and genus resolution within the family between fragment 773 bp at 5’ and the full length of rbcL. Therefore, we conclude that fragment 773 bp at 5’ should be used as DNA barcodes for the Halymeniaceae to reduce the cost and time during phylogenetic analysis. Two taxa Grateloupia newly collected in Vietnam were grouped to the known Phyllymenia, a new genus in Vietnam

Factors Affecting Consumers’ Intention in Vietnam-China Cross-border E-commerce: An Empirical Study in Hanoi, Vietnam

In the era of innovative technologies, the physical border is no longer a concern in exchanging goods thanks to the widespread use of internet connections. On this basis, the study explores the determinants that impact cross-border online consumers’ purchase intentions in Hanoi, Vietnam. As fundamental ideas, the Theory of Planned Behavior (TPB) and the Technology Acceptance Model (TAM) are integrated with the influence of the Regional Comprehensive Economic Partnership (RCEP). The examined factors consist of Consumer Attitude, Subjective Norms, Perceived Behavioral Control, Perceived Usefulness, Perceived Ease of Use, Perceived Risk, Trust, and RCEP. The research was conducted on a survey questionnaire of 253 online shoppers in Hanoi who have experienced cross-border purchasing. The data was processed using several statistical methods, namely descriptive statistics, exploratory factor analysis (EFA), correlation analysis, and regression analysis. The analysis reveals that Consumer Attitude, Subjective Norms, Perceived Behavioral Control, Perceived Usefulness, Perceived Ease of Use, and Trust have a positive influence on the consumer’s intention to cross-border e-commerce (CBEC), while perceived risk and RCEP do not exert any force on the intention. Among these variables, Risk perception and trust have been demonstrated to have the most significant impact on online purchase intention. The outcomes of the study indicate that online retailers or intermediaries adopt a third-party payment processor and publish policies to protect consumers’ private information. It is also suggested that the government should educate the public on the benefits of RCEP, implement the relevant policies, and provide guidance for the sellers to follow to utilize the advantages of RCEP

Rice monitoring using ENVISAT-ASAR data: preliminary results of a case study in the Mekong River Delta, Vietnam

Vietnam is one of the world’s largest rice exporting countries, and the fertile Mekong River Delta at the southern tip of Vietnam accounts for more than half of the country’s rice production. Unfortunately, a large part of rice crop growing time coincides with a rainy season, resulting in a limited number of cloud-free optical remote sensing images for rice monitoring. Synthetic aperture radar (SAR) data allows for observations independent of weather conditions and solar illumination, and is potentially well suited for rice crop monitoring. The aim of the study was to apply new generation Envisat ASAR data with dual polarization (HH and VV) to rice cropping system mapping and monitoring in An Giang province, Mekong River Delta. Several sample areas were established on the ground, where selected rice parameters (e.g. rice height and biomass) are periodically being measured over a period of 12 months. A correlation analysis of rice parameters and radar imagery values is then being conducted to determine the significance and magnitude of the relationships. This paper describes a review of the previous research studies on rice monitoring using SAR data, the context of this on-going study, and some preliminary results that provide insights on how ASAR imagery could be useful for rice crop monitoring. More work is being done to develop algorithms for mapping and monitoring rice cropping systems, and to validate a rice yield prediction model for one year cycle using time-series SAR imagery

Vietnamese Word Segmentation with CRFs and SVMs: An Investigation

PACLIC 20 / Wuhan, China / 1-3 November, 200

A SURVEY ON THE DIFFICULTIES IN WRITING ESSAYS OF ENGLISH MAJORED SOPHOMORES AT TAY DO UNIVERSITY, VIETNAM

This thesis “A study on the difficulties in writing essays of English-majored sophomores at Tay Do University” was conducted to examine the difficulties that second-year students majoring in English often met in writing essays. For this purpose, the participants in this study were 100 English majored sophomores in classes 14A, 14B and 14C at Tay Do University. The interview with 3 extended statements for English majored teachers and a questionnaire with 25 closed statements for students is used as instruments to collect the data. The data from the interview and questionnaire were collected to make clear and prove the problems that the students have had in writing essays. The study figured out some difficulties about background knowledge, vocabulary, grammar structure, idea arrangement and orthography in writing essays faced by English majors sophomores at Tay Do University. Besides, this study also helps students realize their challenges and improve their writing essays.  Article visualizations

Some Characteristics And Allopurinol Release Of Carrageenan/ Allopurinol Films Using Polyethylene Oxide As A Dispersion Aid Agent

This paper presents the effect of carrageenan (CG) on some characteristics and drug release of allopurinol in the presence of polyethylene oxide (PEO) as a dispersion aid agent. The samples were prepared in film shape by solution method, in which, the content of PEO was changed from 1 wt.% to 5 wt.% and the content of allopurinol was fixed at 10 wt.% in comparison with carrageenan weight. FTIR , FESEM, UV-Vis methods were used to evaluate characterizations and morphology of CG/PEO/allopurinol films