DYNAMIC MODEL WITH A NEW FORMULATION OF CORIOLIS/CENTRIFUGAL MATRIX FOR ROBOT MANIPULATORS

The paper presents a complete generalized procedure based on the Euler-Lagrange equations to build the matrix form of dynamic equations, called dynamic model, for robot manipulators. In addition, a new formulation of the Coriolis/centrifugal matrix is proposed. The link linear and angular velocities are formulated explicitly. Therefore, the translational and rotational Jacobian matrices can be derived straightforward from definition, which makes the calculation of the generalized inertia matrix more convenient. By using Kronecker product, a new Coriolis/centrifugal matrix formulation is set up directly in matrix-based manner and guarantees the skew symmetry property of robot dynamic equations. This important property is usually exploited for developing many control methodologies. The validation of the proposal formulation is confirmed through the symbolic solution and simulation of a typical robot manipulator

Groundwork-Based Research to Design Application SCC - Building a Sustainable Community for Children in Mountainous Area

Children’s clothing is a prime example of fast fashion, as their continuous growth requires frequent purchases. This not only impacts the environment but also puts financial strain on parents. Concurrently, many highland children lack essential material and educational resources, contributing to poverty in the region. To address these challenges, local authorities urgently require a sustainable solution that supports children, communities, and localities, fostering comprehensive development. The project development criteria are evaluated based on the United Nations’ 17 sustainable development goals (SDGs). Data was collected through an online survey of 50 married individuals, 162 non-married individuals, and interviews with those who have organized events for children in the highlands. Additionally, insights were obtained from three children from disadvantaged areas. The results indicate that all target groups show a keen interest in social activities for children. Parents facing difficulties accessing charities, and the lack of effective collaboration between charities and local authorities, hinders sustainable development efforts. Keywords: children, SDG, social sustainabilty, communit

Effect of Rare Earth on M7C3 Eutectic Carbide in 13% Chromium Alloy Cast Iron

The crystallization process of hypoeutectic white cast iron consists of the first secreted austenite branch after the reaction of the austenite -carbide crystal is formed, and the phase crystal fills in the middle of the austenite branches. If the austenite branches are small and smooth, the crystals carbide are fine. The cast iron with 13% chromium which has 3 – 3.2% carbon, have the carbide crystalline as M7C3. The elements in rare earth have a strong affinity for oxygen and sulfur to produce rare earth oxides. These rare earth oxides can create heterogeneous germ center for austenite phases and smooth down these phases. The effect of rare earth on the M7C3 and crystals of 13% chrome white iron has been elucidated. Along with the increase of rare earth content, the microstructure of M7C3 with fine finely graded, more uniformly distributed, dispersed throughout the sample surface. When the carbide is fine and dispersion, will contribute to improving the properties of cast iron especially the impact strength as well as the abrasion resistance of the alloy. The research results show that in the presence of rare earth, rare earth elements created with oxygen and form La2O3 and Ce2O3 as the nucleation for the solidification process and create the small fineness of phases. The orientation of the crystal structure of these oxides is similar to the crystal structure orientation of Fe-γ phase. Finding and proving the oxides of rare earth has crystal structure with phase γ which will be small smooth exogenous minds that the microstructure has a smooth, small size

Modified sunflower optimization for network reconfiguration and distributed generation placement

This paper proposed modified sunflower optimization (MSFO) for the combination of network reconfiguration and distributed generation placement problem (NR-DGP) to minimize power loss of the electric distribution system (EDS). Sunflower optimization (SFO) is inspired form the ideal of sunflower plant motion to get the sunlight and its reproduction. To enhance the performance of SFO, it is modified to MSFO wherein, the pollination and mortality techniques have been modified by using Levy distribution and mutation of the best solutions. The results are evaluated on two test systems. The efficiency of MSFO is compared with that of the original SFO and other algorithms in literature. The comparisons show that MSFO outperforms to SFO and other methods in obtained optimal solution. Furthermore, MSFO demonstrates the better statistical results than SFO. So, MSFO can be a powerful approach for the NR-DGP problem

MOTIVATION TO STUDY ENGLISH OF NON-ENGLISH MAJORED FRESHMEN

Motivation is regarded as an influential factor in the success of any activity. It plays a significant role in reaching the desired goals, including learning English. This research aims to analyze the students' motivation and factors affecting their motivation to learn English. The population of this study was 326 freshmen in nine faculties of natural sciences at Tay Do University. The quantitative data was collected through the questionnaire and analyzed by SPSS software. The results show that the students had motivation to learn English, but their motivation levels were not high. Additionally, the students had both intrinsic and extrinsic motivation. However, the latter was higher than the former. Moreover, the results also indicate factors affecting learners’ motivation. The research findings contribute to improving English teaching and learning quality in Vietnam in general and in Tay Do University in particular. Article visualizations

An Assessment of Cough Medicine Dispensing Practice to Children Under Two Years Old in Pharmacies in Ho Chi Minh City Using Simulated-Patient Method

Over-the-counter (OTC) cough and cold medications (CCMs) have been used to treat the symptoms of upper respiratory infection in children for decades. The safety of CCMs in children has been questioned. The data on knowledge of pharmacists in supplying cough medicines for children under two years have been limited. This study aimed to evaluate the pharmacists’ dispensing decisions to manage the cough in children under two years old. A descriptive cross-sectional was carried out in 300 pharmacies in 15 districts in Ho Chi Minh City, Vietnam. The pharmacists were interviewed by a simulated patient. The results showed that, information that pharmacists actively asked the client about the patient and disease symptoms was limited. Most pharmacists did not provide adequate instructions and counsel about using drugs for clients. Only 22/300 (7.33%) of pharmacists appropriately provided cough medicines for children under 2 years old. The main reason of inappropriateness was the deficiency of knowledge about updated contraindication of N-acetylcysteine (93.17%). Pharmacists in pharmacies located in districts 3, 11 and Binh Thanh had higher rate of rational provision than those in other districts. A good and full understanding of the patient symptom helped the pharmacists supply cough medicines more reasonably. The limited caution of pharmacists and the low proportion of pharmacists updating contraindication of N-acetylcysteine should be considered as a warning sign in pharmacy practice in Ho Chi Minh City, Vietnam

Molecular identification of three Habenaria species from Binh Chau-Phuoc Buu Nature Reserve, Vietnam

The present provides molecular data for species of Habenaria diphylla (Nimmo) Dalzell, H. khasiana Hook.f. and H. rostellifera Rchb.f. collected from Binh Chau-Phuoc Buu Nature Reserve, Vietnam for the first time. Along with other DNA sequences from GenBank database, the phylogenetic trees for Habenaria species from Vietnam have been established

Investigating determinants of quality of life: The case of older people in Ho Chi Minh City

This study was conducted to investigate the factors affecting the quality of life in terms of the health of the elderly in Ho Chi Minh City (HCMC), Vietnam. Health production theory was used to form the analytical framework for the study. The data set of 300 surveyed elderly people, which was randomly drawn from the list of 841,000 older people in HCMC by Excel random function, was used for quantitative analysis, including Exploratory Factor Analysis (EFA) and linear regression. Research results show that gender and marital status are not statistically significant while education, employment, bonding, bridging, and linking social capital statistically significant impact on the quality of life of the elderly. Specifically, the level of education improves the quality of life while employment reduces the quality of life. This finding is an important implication for policies related to the retirement age of employees. The research results have also provided empirical evidence on the potential of social capital, a resource existing in the network of relationships, in improving the quality of life besides other traditional resources. This finding is an important basis for policymakers in mobilizing social capital resources in the context of resource scarcity

MULTI-PIXEL PHOTON COUNTER FOR OPERATING A TABLETOP COSMIC RAY DETECTOR UNDER LOOSELY CONTROLLED CONDITIONS

The multi-pixel photon counter (MPPC) has recently emerged as a great type of silicon photomultiplier to replace or compensate for conventional vacuum-based photomultiplier tubes. An MPPC provides many advantageous features, such as high electrical gain, outstanding photon detection efficiency, fast timing response, immunity to magnetic fields, low-voltage operation, compactness, portability, and cost-effectiveness. This article examines the electrical and optical characteristics of an MPPC under loosely controlled environmental conditions. We also report a measurement of the light yield captured by the MPPC when a cosmic ray passes through the plastic scintillator, demonstrating that such a setup is suitable as a simple, cost-effective tabletop cosmic ray detector for educational and research purposes

Robust Adaptive Cerebellar Model Articulation Controller for 1-DOF Nonlaminated Active Magnetic Bearings

This paper presents a robust adaptive cerebellar model articulation controller (RACMAC) for 1-DOF nonlaminated active magnetic bearings (AMBs) to achieve desired positions for the rotor using a robust sliding mode control based. The dynamic model of 1-DOF nonlaminated AMB is introduced in fractional order equations. However, it is challenging to design a controller based on the model\u27s parameters due to undefined components and external disturbances such as eddy current losses in the actuator, external disturbance, variant parameters of the model while operating. In order to tackle the problem, RACMAC, which has a cerebellar model to estimate nonlinear disturbances, is investigated to resolve this problem. Based on this estimation, a robust adaptive controller that approximates the ideal and compensation controllers is calculated. The online parameters of the neural network are adjusted using Lyapunov\u27s stability theory to ensure the stability of system. Simulation results are presented to demonstrate the effectiveness of the proposed controller.The simulation results indicate that the CMAC multiple nonlinear multiple estimators are close to the actual nonlinear disturbance value, and the effectiveness of the proposed RACMAC method compared with the FOPID and SMC controllers has been studied previously