STUDENTS’ ERRORS IN SOLVING MATHEMATICAL WORD PROBLEMS AND THEIR ABILITY IN IDENTIFYING ERRORS IN WRONG SOLUTIONS

Solving mathematical word problems is a difficult, complex and intellectual activity. The formation of problem solving skills is much more difficult than calculation skills because the problems are related to many concepts and a lot of mathematical relationships. Therefore, students are inevitable to commit errors to deal with them. This study shows the errors of 160 3rd grade students regarding some kinds of word problems in Mathematics 3 in Vietnam. The results indicate that children commit many errors due to many different reasons such as: subjectivity, carelessness, wrong application of the calculation rules, incorrect identification of problem kinds and wrong calculation.  Article visualizations

RELATIONSHIPS BETWEEN THE BELIEF PRACTICES AND THE ECOLOGICAL ENVIRONMENT WITHIN SOUTHWEST COASTAL FISHING COMMUNITY IN VIETNAM APPROACHING FROM THE THEORY OF CULTURAL ECOLOGY

This article aims to examine the relationship between the belief practices and the ecological environment within Southwest coastal fishing communities in Vietnam. The fishermen’s religious practices are diverse and adaptable to the coastal environment which significantly impacts their livelihood. Case-study research with observation and in-depth interviews indicate the obvious differences in the coastal environment between An Thuy fishing community (Ba Tri District, Ben Tre Province) and Song Doc fishing community (Tran Van Thoi District, Ca Mau Province) in the Southeast and Southwest of the East Sea respectively. The surveyed differences directly affect religious activities, including the time of festivals, offerings, cuisine, and decorations in the two researched areas. In particular, the research result support the scientific theory defined by Julian Stewart, an anthropologist of cultural ecology

Gate modulation of the long-range magnetic order in a vanadium-doped WSe2 semiconductor

We demonstrate the gate-tunability of the long-range magnetic order in a p-type V-doped WSe2 monolayer using ab initio calculations. We found that at a low V-doping concentration limit, the long-range ferromagnetic order is enhanced by increasing the hole density. In contrast, the short-range antiferromagnetic order is manifested at a high electron density by full compensation of the p-type V doping concentration. The hole-mediated long-range magnetic exchange is ~70 meV, thus strongly suggesting the ferromagnetism in V-doped WSe2 at room temperature. Our findings on strong coupling between charge and spin order in V-doped WSe2 provide plenty of room for multifunctional gate-tunable spintronics.Comment: 13 pages, 4 figures, 1 tabl

The Effectiveness of Applying Realistic Mathematics Education Approach in Teaching Statistics in Grade 7 to Students' Mathematical Skills

The research was carried out to verify the effectiveness of applying Realistic Mathematics Education (RME) on the development of skills required by students in statistical content in grade 7. For achieving research objectives, the pedagogical experiment was conducted in the form of intrinsic legalization for forty-eight 7th-grade students at Tang Phu Nhan B Junior School, District 9, Ho Chi Minh City, Vietnam. Accordingly, data on pre-test results, study sheets, post-test, and student learning performance were collected and analyzed qualitatively. The results were assessed based on the criteria corresponding to the required skills for the statistical content, including the criteria for data collection, classification, and representation according to the given criteria for the skill, data collection, and organization capabilities; simple problem formation and problem-solving criteria arise from the existing statistical figures and charts for data analysis and processing skills. The primary mathematical statistics method was used to evaluate the achievement level of students for each criterion. Thereby, the experimental results showed that applying the RME approach in teaching statistical content positively impacted the development of some skills that students needed to achieve. Also, a number of guidelines were provided to guide the enhancement of RME activities

Turbine Engine with Differential Gear Driven Fan and Compressor

A gas turbine engine provides a differential gear system coupling the turbine to the bypass fan and the compressor. In this manner, the power/speed split between the bypass fan and the compressor can be optimized under all conditions. In the example shown, the turbine drives a sun gear, which drives a planet carrier and a ring gear in a differential manner. One of the planet carrier and the ring gear is coupled to the bypass fan, while the other is coupled to the compressor

Guided Tuning of Turbine Blades: A Practical Method to Avoid Operating at Resonance

In gas turbine applications, forced vibrations of turbine blades under resonant-or nearly resonant-conditions are undesirable. Usually in airfoil design procedures, at least the first three blade modes are required to be free of excitation in the operating speed range. However, not uncommonly, a blade may experience resonance at other higher natural frequencies. In an attempt to avoid resonant oscillations, the structural frequencies are tuned away from the excitation frequencies by changing the geometry of the blade. The typical iterative design process-of adding and removing material through restacking the airfoil sections-is laborious and in no way assures an optimal design. In response to the need for an effective and fast methodology, the guided tuning of turbine blades method (GTTB) is developed and presented in this paper. A practical tuning technique, the GTTB method is based on structural perturbations to the mass and stiffness at critical locations, as determined by the methodology described herein. This shifts the excited natural frequency out of the operating speed range, while leaving the other structural frequencies largely undisturbed. The methodology is demonstrated here in the redesign of an actual turbine blade. The numerical results are experimentally validated using a laser vibrometer. The results indicate that the proposed method is not computationally intensive and renders effective results that jibe with experiments

A SURVEY OF STUDENTS’ ABILITY OF IDENTIFYING ERRORS IN WRONG SOLUTIONS FOR THE MATHEMATICAL PROBLEMS RELATED TO THE MONOTONICITY OF FUNCTIONS

The monotonicity of a function plays an important role in the general mathematics curriculum in Vietnam, because it is considered as an effective tool for solving mathematical problems involved with the monotonic intervals of functions, their extreme, absolute maximum value and absolute minimum value. Normally, students commit errors in solving these problems because of their complexity and difficulty. In addition, specific characteristics of knowledge also make children make mistakes. The sample consisted of 362 students, and they had the task of identifying errors in false assumptions. From the results of the survey, it was found that when dealing with the monotonicity of the functions, students were still misled.  Article visualizations

FACTORS AFFECTING THE ACADEMIC RESULTS OF MASTER STUDENTS IN MATHEMATICS EDUCATION AT CAN THO UNIVERSITY, VIETNAM: A SURVEY STUDY

The study results were based on the survey data of 24 students  studying the master program in math education at Can Tho University, Vietnam. We used the questionnaire to find out the factors affecting students' learning outcomes: Learning time, learning conditions, learning environment, personal level, learning methods, collaborative learning, learning attitudes. The results show factors such as learning conditions, learning environment, time for leaning, qualifications, teaching methods, learning methods, cooperation in learning, attitude in learning are factors that significantly affect the learning of master students in Mathematics education. Therefore, universities with high-level training programs should have adequate facilities for students' learning; lecturers know how to use teaching methods to promote self-study and self-study for students, improve their ability to work independently, the ability to cooperate in the learning and research process of students. In other words, universities must uphold  their responsibilities when implementing intensive training programs, helping learners with necessary competencies as expected of the community and society.  Article visualizations