422 research outputs found

    Difference in quality of life and associated factors among the elderly in rural Vietnam

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    Background. In Vietnam today, many generations remain living together in a family. With escalating urbanization and population aging, mental health disorders and the quality of life (QoL) among the elderly are gradually presenting themselves as of great concern. The objective of this study was to examine gender differences in QoL and some associated factors among the elderly in rural Vietnam using the QoL scale of WHO (WHOQOL-BREF). Methods. A cross-sectional study using quantitative methods. Results and Conclusions. The proportion of the elderly men having higher level of QoL in physical health, psychological health and environment was higher than that of their women counterparts. Reversely, of those having medium and lower QoL, females made up a larger proportion than males. The overall QoL score in elderly men (75.32) was higher than that of women (72.32) and the same pattern was witnessed in all four domains of QoL. While higher QoL in elderly men was significantly correlated with 5 factors, aged ‚Č• 80 years, following Buddhism and Christianity, having better connection and without illness in the past 6 months, these among female counterparts are aged ‚Č• 80 years, completing secondary level or above, having medium and high socioeconomic status and without illness in the last 6 months. ¬© 2017, Pacini Editore S.p.A. All rights reserved

    Diversity of plant-parasitic nematodes on medicinal plants in Melinh station for biodiversity, Vinh Phuc Province, Vietnam

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    Plant-parasitic nematodes are known as one of the most important pests attacking various plants in the world, and investigating the nematode component is very essential for management of this pest and prevent damage to plants in general. Our survey of plant-parasitic nematodes on medicinal plants in Melinh Station for Biodiversity, a place for conservation of precious plants and animals in Vietnam, identified ten species that belong to nine genera, five families, and two orders of plant-parasitic nematodes parasitizing six medicinal plants. Excoecaria cochinchinensis was parasitized by the highest number of nematode genera (5 genera, including Xiphinema, Discocriconemella, Meloidogyne, Helicotylenchus, and Hemicriconemoides), while Hymenocallis littoralis was associated with the highest number of plant-parasitic nematodes (2060 nematodes/250g soil). The results also showed that Discocriconemella limitanea was found to be a dominant species with the highest number of individuals on 6 medicinal plants, and the genus Helicotylenchus had the highest frequency of appearance (5/6 plants or 83.3%). These nematodes caused symptoms such as yellowing leaves, root galls, and root lesions, which directly affect the quality and yield of medicinal plants. Based on the results, this study showed that plant-parasitic nematodes are a potential threat to the cultivation of medicinal plants in Melinh Station for Biodiversity, and thus, control measures should be applied to ensure sustainable cultivation of medicinal plants in this place

    Research on Using Dolomite Aggregate as Cement Treated Base for Highway Pavement Construction in Ninh Binh, Vietnam

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    Dolomite is commonly used in the construction of highway pavement in the world. However, there are still no concrete specifications or regulations on the use of dolomite for highway construction. Dolomite is available in huge quantities in NinhBinh Province. This is a high potential material for grain bases of highway pavement structure. The alternative material could be a considerable contribution to diversify the supply of aggregate resources for highway pavement construction in the province, and thus contribute to the conservation of natural landscape heritages and limestone resources for related building materials manufacturing industries. In order to evaluate the use of dolomite in highway pavement construction, a research program is conducted to test the working capacity of the cement treated dolomite aggregate, which is intended to use as upper base material in pavement structure. The experimental results showed that the mechanical indicators of the mixture satisfy the requirements for the base layers of highway pavement structure

    An efficient approach to measure the difficulty degree of practical programming exercises based on student performances

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    oai:ojs.www.rev-jec.org:article/282This study examines the generality of easy to hard practice questions in programming subjects. One of the most important contributions is to propose four new formulas for determining the difficulty degree of questions. These formulas aim to describe different aspects of difficulty degree from the learner's perspective instead of the instructor's subjective opinions. Then, we used clustering technique to group the questions into three easy, medium and difficult degrees. The results will be the baseline to consider the generality of the exercise sets according to each topic. The proposed solution is then tested on the data set that includes the results of the two subjects: Programming Fundamentals, Data Structures and Algorithms from Ho Chi Minh City University of Technology. The most important result is to suggest the instructors complete various degrees according to each topic for better evaluating student's performance

    Designingan Adaptive PID Controller for Dissolved Oxygen Control of the Activated Sludge Wastewater Treatment using Hedge Algebras

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    In this paper, we present the design methodology of the coefficients of adjustment of classical PI controller based on hedge algebras approach (HA - Hedge Algebras) to improve the quality of operation of the system. The adjustment works online with a wide range of adjustment enough around the value calculated by empirical methods Ziegler - Nichols. Subjects selected for trial is the controller method for dissolved oxygen in the wastewater treatment system by activated sludge method. Through system simulation in Matlab or Simulink environment at some different reference values, the results have been evaluated for quality control shows that the response time and overshoot reduce significantly, static deviation level is small. Through these results, it can be tested on the control system for more complex subjects to evaluate the effectiveness of methods and practical applications on the industrial control systems

    The Improvement Model of Navigational Safety for Inland Waterway Transport

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    This paper aims at evaluating navigational safety for inland waterway transport (IWT). In doing so, the literature and operational features of IWT were initially reviewed to figure out risk elements (REs) influencing the navigational safety for IWT. After that, a fuzzy Analytic Hierarchical Process (AHP) approach was adopted to estimate the weight for the likelihood and consequence measures of REs. Then, continuous risk matrix (RM) was introduced to identify REs\u27 risk level. Lastly, to test the proposed research model\u27s applicability, IWT operators across Vietnam were empirically surveyed. The empirical findings could be useful for IWT operators in launching managerial policies to boost their navigational safety. Furthermore, the proposed risk evaluation framework may serve as a methodological reference in relevant literature

    Modeling of parallel power MOSFETs in steady-state

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    In high-power applications, multiple power MOSFETs are connected in parallel and treated as a single switch in order to handle much larger total currents. In this paper, a parallel power MOSFETs model from the turnoff state until they reach their steady state is introduced. The model represents the relationship between each power MOSFET's gate voltage and the current distribution among them. The study's key purpose is to use the model for dealing with the asymmetry in sharing current and power loss between these semiconductor devices during the steady state region.Comment: 10 pages, 7 figures, The 2023 INTERNATIONAL SYMPOSIUM ON ADVANCED ENGINEERING (ISAE2023

    Dynamic response analysis of truss bridges under the effect of moving vehicles

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    With the characteristics of heavy and concentrated loads, the influence of moving loads on the dynamic response of the bridges is significant. Therefore, in this paper, the dynamic response of a large-scale truss bridge is studied to consider the effect of the various parameters of moving loads. The considered main parameters consist of moving mass, moving velocity, and type of moving loads. The nonlinear dynamics of the bridge based on time history analysis are obtained using the Wilson- ¬†method. four time history ‚Äď based dynamic analysis method including modal superposition in frequency domain, modal superposition in time domain; direct time integration, and direct solution in the frequency domain are employed to analysis the obtained results. To compare the effectiveness of the aforementioned method. A large-scale railway truss bridge is employed for dynamic response analysis. The obtained results give more insight into the nature of the problem and help to determine the significant parameters of moving load affecting the bridge response
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