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Currently, the research on the application of Single point incremental forming technology (SPIF) in Vietnam is limited. Therefore, the study of technology and equipment for the fabrication of SPIF machine and research on the ability of deformation of the formed material sheet is necessary and should be urgently carried out. The paper proposes a new approach to modularizing the structure of the Single point incremental forming machine by using standard parts, thereby improving the quality and reducing the cost of the machine and improving accuracy of the machine.

This study aims to assess high school students' learning outcomes, their achievement of goals and fulfilling academic requirements and how the entire teaching and learning process takes place. The study, consisting of an experimental group and a control group was conducted for pre-test and post-test comparisons of the academic performance of 88 10th grade students. 44 students were selected as the experimental group that underwent a specific teaching strategy to monitor their development of qualities and competencies in one semester, and the remaining 44 students acted as the control group. The data collected after the tests were analyzed using SPSS software (V20). The results showed that the students in the experimental group had better academic results than those in the control group. The findings of this study have implications for policy, further research as well as approaches for the assessment of students’ development of qualities and competencies in Vietnam.

Radio Direction Finding system is a system that determines the direction or coordinates of radio signal sources. The main function of this system is to determine the direction of arrival (DOA) of an incident radio wave. DOA information plays an important role in array signal processing and has many applications in communications, radar, seismic survey... In this paper, with the simulated signal data set obtained at the linear antenna array (ULA), the Long Short-Term Memory (LSTM) network model is used to estimate the DOA. The performance of the method is evaluated based on the RMSE parameter and compared with MUSIC, DNN algorithms in different cases such as: deviation of incident angle of radiation sources, signal-to-noise ratio (SNR).

The large sea urchins (Diadematidae) are widely distributed worldwide, from temperate to tropical waters. Diadematidae is an important herbivore in the coral reef ecosystem through herbivore-algal-coral interaction, which maintains the reef’s health. Many studies of Diadematidae have been performed around world, but in Vietnam, there is little known about the ecology of this group. Here, we first investigated the assemblage structure of Diadematidae in Northern Vietnam. We observed 43 sites of representative coral reefs in Ba Mun - Co To, Cat Ba - Ha Long, and Hon Me. Based on the surveys, we found four species of considerable size sea urchins, of which the most common species is Diadema setosum (79.8% of the total), Enchinothrix calamaris (10.1%), E. diadema (8.3%), and D. savignyi (1.8%). Among three study regions, Hon Me is the most diverse. In addition, Hon Me also has the highest density of sea urchins. However, this value is generally low compared to that in Southern Vietnam and other neighboring countries. Further study is needed to investigate the ecology and reproductive biology of Diadematidae to provide fundamental information for sustainable exploitation and conservation.

The focus of the study is to investigate effects of corn blends on exhaust emissions using Artificial Neural Network (ANN) approach. A series of experiments were conducted on the water-cooled multi-cylinder engine to calibrate the emissions of CO, THC, and NOx. The biodiesel was prepared using the transesterification process. Furthermore, the MgO nanoparticles of 10, 15, 20 and 30 ppm was added to the corn blends through ultrasonication. The ANN is developed to anticipate the emission characteristics of the compression ignition engine. As engine load increases, the emission of carbon monoxide and total hydrocarbons decreases significantly. On the contrary, the emission of NOx gases spiked at higher load. The ANN back propagation algorithm is developed with four input network and one output network to predict the results. The blends C10, C15, C20, and C30 were studied with the developed ANN by varying the engine load. Besides, the highest and lowest value of mean square errors and correlation coefficient were found for CO, THC, and NOx. Meanwhile, the optimized regression coefficients for the emission parameters ranged between 0.8875 and 0.9858. The predicted correlation coefficients for CO, THC, and NOx were 0.9985, 0.9978 and 0.9986, respectively.

La Cultura de calidad tiene un papel decisivo en el mantenimiento y la mejora de la calidad de las universidades privadas vietnamitas con el fin de satisfacer mejor la demanda de los clientes. Sin embargo, no hay universidades privadas en Vietnam que hayan construido una cultura de calidad sobre la base de un estudio factible y práctico. Por ello, este estudio se implementó por primera vez en Vietnam para abordar esa situación de las universidades privadas. Basado en estudios teóricos y prácticos, este estudio tiene como objetivo proponer soluciones para la construcción de la cultura de calidad con el fin de mejorar la calidad de la formación y la educación, la investigación científica y el servicio público de las universidades privadas vietnamitas.

The application of bamboo by-products such as bamboo branches, chips to recycle and produce pressed bamboo pulp is an urgent task in Vietnam. It perfectly replaces natural wood with artificial wood embryos from bamboo powder, which has both economic benefits of reserving the source of raw materials, environmental protection... The paper presents a study of the influence of technological parameters on the water absorption and swelling thickness of pressed bamboo pulp plywood in order to ameliorate the quality of pressed bamboo pulp plywood in production of new materials for civil engineering with environmentally friendly bamboo wood pulp materials.

Blended Learning is a flexible learning model that combines the creative advances and technology of online learning with the interaction and engagement of face-to-face learning. One of the best ways to deal with the need for \"learning anywhere, learning anytime, learning everything, learning flexibly, learning openly and learning for the whole life\", which becomes an inevitable trend currently. This requires teachers to design a course and organize the teaching process to ensure the formation and development of learners’ self-learning ability as well as the cultivation of the skills in using and mastering technology. The paper outlines the steps to be taken to design a blended learning course to help teachers in the course design suitable for their teaching process at university meeting the fourth industrial revolution.

This study aimed to evaluate the effect of domestic wastewater treatment on the horizontal subsurface flow-constructed wetlands (HSSF-CWs) using Brachiaria mutica vegetation. We used two wetland models: one with plants and the other without plants. These models were built according to the following dimensions (L × W × H = 1.2 × 0.4 × 0.8 m) and operated at four organic loads (30, 60, 90, 120 kg COD/ha.day) for 3 months. Parameters including pH, COD, BOD5, TSS, total nitrogen (TN), total phosphorus (TP), total coliforms were analyzed. The levels of pollutants in domestic wastewater after treatment were significantly reduced. The values of percentage removal (%) were as follows: COD 81.58%, BOD5 93.3%, TSS 67.2%, TN 58.6%, TP 85.5%, and total coliforms 90.4%. Our results also indicate that the organic loading rate (OLR) ranging between 60 and 120 kg COD/ha.day is suitable to be implemented in the actual domestic wastewater treatment.

The study aims to identify the main factors affecting the motivation of officials and employees at the Vietnam National University of Forestry, Southern Campus. The research team collected primary data through the survey of 215 officials working at Vietnam National University of Forestry, Southern Campus. The research methods used are descriptive statistics, exploratory factor analysis (EFA), scale test (Cronbach’s Alpha), regression correlation analysis, and testing of the research hypotheses. As a result, 5 factors have been found to be affecting employees' working motivation, including: promotion opportunities and career development; wages, bonuses and benefits, stable jobs; leader; friendship colleague. On this basis, the study proposes a number of recommendations to improve the motivation of school officials.

In this study, strontium is used as an alloying element for improving the pitting resistance of Mg-5Al-4Sn based alloys in an alkaline solution. Potentiodynamic polarization measurements suggest that the addition of strontium increases the robustness of the pitting resistance as a result of the higher pitting potential and wider range of passive potential. Electrochemical impedance spectroscopy (EIS) confirms the formation of a solid passive film on the alloy surface due to a significant increase in the passive film and the charge transfer resistance, as well as lower film and double layer constant phase element magnitude values. Additionally, the potentiostatic polarisation results also show a lower passive current density and passive film stability, resulting in an increase in the breakdown time when the amount of strontium added to the alloy increases from 0.0 to 1.0 wt%. Furthermore, the scanning electron microscopy results indicate that insignificant corrosion is observed on alloy specimens containing strontium, whereas there is fierce corrosion on alloy based surfaces. This robust corrosion resistance could be attributed to the α-grain reduction and refined precipitates at the alloy grain boundaries, resulting in promoted formation of the passive film which is formed from a mixture of magnesium, aluminum and tin oxides/hydroxides, as confirmed by the X-ray photoelectron spectroscopy results.

The vascular endothelial growth factor 165 (VEGF165) is a quintessential biomarker in cancers. An easy and precise tool for the early detection of malignancies is required for rapid care and metastasis prevention. Cobalt-based metal–organic framework (Co-BTC-GO-MOF) nanoparticles have been used as a signal carrier for the anti-VEGF165 signaling antibody. Cobalt-based MOF was synthesized using cobalt (Co), benzene-1,3,5-tricarboxylate (BTC), and graphene oxide (GO) applying a hydrothermal method. Structure, compositions, size and morphology of the qualified sensor are determined by using distinctive analytical techniques. The Co-MOF nanoparticles are found to be thermostable, as revealed by thermal stability assay. The strategy utilises an impedimetric and differential pulse voltammetry (DPV) techniques in the presence of the [Fe(CN)6]3−/4− redox system. Compared to earlier results, this assay resulted in higher sensitivity with the limit of detection (LOD) found to be 5.23 pM in a 0.01 M buffer solution of pH 7.4 using linear scale voltammetry at room temperature. The resulting Co-BTC-GO-MOF immunosensor shows high responsiveness and selectivity in detecting VEGF165 in real-time serum samples of cancer patients. The electrochemical performance studies confirm that the intended proposed immunosensor could pave the way for the future advancement of high-performance, sensitive, reproducible and robust immunosensors for the cost-effective and initial phase detection of cancer in the future.

Electric vehicles have become a trend as a replacement to gasoline-powered vehicles and will be a sustainable substitution to conventional vehicles. As the number of electric vehicles in cities increases, the charging demand has surged. The optimal location of the charging station plays an important role in the electric vehicle transit system. This chapter discusses the planning of electric vehicle charging infrastructure for urban. The purpose of this work develops an electric vehicle fast-charging facility planning model by considering battery degradation and vehicle heterogeneity in driving range, and considering various influencing factors such as traffic conditions, user charging costs, daily travel, charging behavior, and distribution network constraints. This work identifies optimal fast-charging stations to minimize the total cost of the transit system for deploying fast-charging networks. Besides, this chapter also analyzes some optimization modeling approach for the fast charging location planning, and point out future research directions.

This research presents an improved control method for the robot manipulator system based on the proportional-derivative technique and neural networks. In the proposed strategy, the proportional-derivative controller based on the filtered tracking error technique has been modified such that the proportional-derivative gain parameters are adaptively updated. Similar to the conventional intelligent control methods, the neural networks approximator is applied to relax the unknown dynamics of the robot control system. In addition, the compensator-typed robust controller is also considered to eliminate inevitable approximating errors and unknown disturbances of the control system. By using the Lyapunov stability theorem for the proposed control design procedure, the tracking control and stability are guaranteed. The comparative simulation results will provide clearly the evident to prove effectiveness of the proposed approach.

Additional file 2: Figure S1. Ls means of the line effect on the LR statistics $${b}_{w,p}$$ b w , p (left panel) and of the type of SBV on $${b}_{w,p}$$ b w , p (middle panel), and $${\rho }_{w,p}$$ ρ w , p (right panel) evaluating the quality of the model to predict SBV based on phenotypic information on ascendants and collateral relatives of the focal individuals. Figure S2. Ls means of the type of SBV on the LR statistics $$\Delta {\mu }_{w,p}$$ Δ μ w , p , evaluating the quality of the model to predict SBV based on phenotypic and pedigree information.

Additional file 1: Table S1. Descriptive statistics of the data. Table S2. Numbers of records, animals with phenotype, sires, and dams per line and generation

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Organ and effective doses of adult for external exposure to photons uniformly distributed in soil were calculated using a MIRD-5 type phantom and MCNP code. The calculations were performed for mono-energic photon sources with source energies from 0.01 MeV to 5 MeV. The effective dose coefficients in this calculation using MCNP code were compared to the calculated results in report of Keith F. Eckerman và Jeffrey C. Ryman.