244 research outputs found

    Co-simulation of self-adjusting fuzzy PI controller for the robot with two-axes system

    Get PDF
    This paper presents the co-simulation of the self-adjusting fuzzy PI controller to control a two-axes system. Each axis was driven by a permanent magnet linear synchronous motor (PMLSM). The position and speed controller used the fuzzy PI algorithm with parameters adjusted by a radial basis function neural network (RBFNN). The vector control was applied to the decoupled effect of the PMLSM. The field programmable gate array (FPGA) was used to control both axes of the system. The very high-speed integrated circuit-hardware description language (VHDL) was developed in the Quartus II software environment, provided by Altera, to analyze and synthesize designs. Firstly, the mathematical model of PMLSM and fuzzy PI was introduced. Secondly, the RBFNN adjusted the knowledge base of the fuzzy PI. Thirdly, the motion trajectory was introduced for testing the control algorithm. Fourthly, the implementation of the controller based on FPGA with the FSM method and the structure of co-simulation between Matlab/Simulink and ModelSim were set up. Finally, discussion about the results proved the effectiveness of the control system, determining the exact position and trajectory of the XY axis system. This research was successful in implementing a two-motor controller within one chip

    Analysis of the Factors Affecting the Household Income of Ethnic Groups in Vonhai District, Thai Nguyen Province

    Get PDF
    Ethnic groups by households in Vo Nhai District often inhabit in rural areas with low income and their life is much more difficult. Therefore, it’s necessary to study on the factors affecting their income in order to find a solution to improve their income. This research has used Cobb – Douglass Production Function, applying Stata software to evaluate the factors affecting household income of minorities. By collecting information from 310 households living in Vo Nhai district, Thai Nguyen province, Vietnam, the result of analysis showed that age of householder, cost, number of inhabitants in the family, level of education of the householders, employees, assets, land areas, bank loans which have an impact on the household income of ethnic groups. The study proposed solutions to help poor households expand on their production, improve their income, and enhance their living

    Antibacterial and Antioxidant Activity of Rhodomyrtus Tomentosa and Cinnamomum Zeylanicum Crude Extracts

    Get PDF
    The aim of this study was to investigate the extraction method for R. tomentosa and C. zeylanicum leaves and the evaluation of antibacterial and antioxidant activities of crude extracts. The results of the study showed that the active ingredients of crude extracts were clearly separated by Thin-layer chromatography and the presence of rhodomyrtone in R. tomentosa crude extract and cinnamaldehyde in C. zeylanicum crude extract. R. tomentosa crude extract was antibacterial activity against Staphylococcus aureus with 13.1 mm of inhibition zone, but is not effective against Salmonella Typhimurium. C. zeylanicum leaf extract did not show antibacterial activity on both S. aureus and S. Typhimurium. At a dilution of 1/2 of the R. tomentosa crude extract can completely inhibit S. aureus growth. This study also indicated the presence of antioxidant compounds such as flavonoids, tannins, phenols and terpenoids in C. zeylanicum and R. tomentosa crude extracts. The results showed that R. tomentosa and C. zeylanicum crude extracts should be used as a biotherapy alternative to antibiotic therapy. However, further study would be needed to investigate the antibacterial activity of crude extracts in vivo

    Challenges And Opportunities For The Development Of Infrastructure After ‘Oda Graduation’ - Moving Towards Sustainable Development: Case Study Of Vietnam

    Get PDF
    The research on ODA will be focused on its relation to Goal 17, the Partnership, considered a major issue by the researchers, especially in the case of Vietnam as a developing economy. ODA was mainly used for investing in economic infrastructure when Vietnam witnessed a downfall in receiving financial aid due to its significant economic growth. ODA helped Vietnam transform from one of the world’s poorest nations into a lower middle-income country and soon, this is going to lead to the ‘ODA Graduation’. However, the process has just begun. The country is still in a process of industrialization and modernization and its socio-economic situation has not been stable or solid. By all means, ODA is not only a financial resource, it also helps the country to accomplish Sustainable Development Goals (SDGs) of the UN. ‘ODA Graduation’ means that the economy of Vietnam has faced certain challenges such as increasing pressure of outbound debts; raising impact on social development or imbalance between high capital recovery investments and public-services investments. However, ‘ODA Graduation’ has brought certain opportunities such as increasing Vietnam’s independence in capital mobilization, preventing the removal of tariffs barrier, reducing losses and waste of funds. This research gives recommendations for improving Vietnam’s economic situation and can help overcome the difficulties in the period of ‘ODA Graduation’

    Ureaplasma urealyticum and Mycoplasma genitalium detection and sperm quality: A cross-sectional study in Vietnam

    Get PDF
    Background: Ureaplasma urealyticum (U. urealyticum) and Mycoplasma genitalium (M. genitalium) may colonize the male genital tract. However, the negative effects of these bacteria on overall sperm quality, including semen pH, sperm concentration, motility, morphology, and total sperm count remain unclear. Objective: This study aimed to determine the presence of genital U. urealyticum and M. genitalium in semen and evaluate the effect of these organisms on sperm quality. Materials and Methods: A cross-sectional study was conducted on 380 men from infertile couples at a tertiary university hospital from July 2017 to June 2018. Semen quality was analyzed according to the World Health Organization 2010 standard, and U. urealyticum and M. genitalium were detected in the semen samples using polymerase chain reaction. Results: 338 men (88.9%) presented with at least one abnormal semen parameter. The detection rates of U. urealyticum and M. genitalium were 16.05% and 0.79%, respectively. There was no significant difference between the Ureaplasma-positive group and the Ureaplasma-negative group in terms of sperm characteristics. Sperm motility and sperm vitality in the Mycoplasma-positive group were much lower than those in the Mycoplasma-negative group (p = 0.02 and p < 0.001, respectively). Conclusion: The presence of U. urealyticum in the semen of infertile men did not affect the sperm characteristics. Although the positive rate of M. genitalium was low, colonization by these bacteria was more likely to negatively affect sperm quality. Key words: Ureaplasma urealyticum, Mycoplasma genitalium, Infertility, Spermatozoa

    GENERATION OF BACILLUS SUBTILIS CLONE DISPLAYING METAL-BINDING POLYHISTIDYL PEPTIDE

    Full text link
    Joint Research on Environmental Science and Technology for the Eart

    Simulink/Modelsim Co-Simulation and FPGA Realization of Speed Control IC for PMSM Drive

    Get PDF
    AbstractPMSM (Permanent Magnetic Synchronous Motor) has been increasingly used in many high performance application due to its advantages of high power density, high power factor and efficiency. The design and implementation of a fuzzy-control based speed control IC for PMSM from Simulink/Modelsim co-simulation to FPGA (Field Programmable Gate Array) realization is presented in this paper. Firstly, a SVPWM scheme, vector control method and fuzzy controller are derived and applied in the speed control IC of PMSM drive. Secondly, the Very-High-Speed IC Hardware Description Language (VHDL) is adopted to describe the behavior of the aforementioned control algorithms. To evaluate the effectiveness and correctness of the proposed speed control IC, a co-simulation work performed by Matlab/Simulink and Modelsim is firstly conducted. Then, an experimental system by FPGA chip, Nios processor and motor driving board is set up to further validate the performance of the proposed speed control IC. Finally, the results in simulation and in experiment will be compared and discussed

    Factors influencing the willingness-to-pay of internet users in Vietnam for the fee-based online contents

    Get PDF
    The aim of this study is to identify key factors that influence the willingness-to-pay (WTP) of Internet users in Vietnam for fee-based online contents. The study collects 309 suitable questionnaires filled by internet users over 18 years old and living in Vietnam, who frequently use online contents and have ideally made payment for online contents. The analysis results indicate that the willingness-to-pay for the fee-based online contents of Vietnamese users are influenced by their attitudes toward paying and ethical self-efficacy for online piracy. The study also identifies the antecedents of attitude, which include the perceived benefits of usefulness and enjoyment, the perceived sacrifice of the fee, social influences from other people, and especially the free mentality. The study then suggests managerial implications to online content providers in enhancing WTP for the fee-based online contents in Vietnam

    Communication activities of students with the social cultural environment during floods: A case study in Thua Thien Hue province, Vietnam

    Get PDF
    This study   aims to explore the variances in communication behaviours among undergraduate students within the social-cultural context.  A total of 104 participants (40 lecturers and six managers) were selected from two universities, namely Hue University of Science and Hue University of Education. The collected data was subsequently evaluated. The findings suggest that there are   slight differences between male and female students. This   study highlights significant differences in involvement among Kinh ethnic students   and students from other ethnic groups. Furthermore, the geographical location and sociocultural environment of a region significantly influence the communication behaviors and preferences of students. Students demonstrate higher mean scores in diverse communication activities as compared to lecturers. The results highlight the significance of gender, ethnicity, geographic location   and student status in influencing students' participation in communication. Recognizing and addressing these differences can help in the development of effective communication strategies, the development of inclusive environments   and the encouragement of positive social interactions among various groups of students.  The implications for students' well-being, academic success and intercultural competency might be explored in more detail in further studies by examining the fundamental variables that lead to these differences

    The Role of Social Network Sites in English Language Teaching_Harnessing the Potential of Facebook and YouTube as Learning Tools

    Get PDF
    This paper provides a comprehensive review of the role of Social Network Sites (SNSs) in the context of English as a Second Language (ESL) and English as a Foreign Language (EFL) teaching and learning. It examines the definitions and potential applications of SNSs, with a specific focus on Facebook and YouTube. The paper discusses the educational and instructional implementations of these SNSs, as well as the challenges and drawbacks faced by both teachers and students when utilizing them. Furthermore, it explores the pedagogical implications of incorporating the cutting-edge features offered by SNSs, aiming to bridge the gap between traditional and technologically driven learning environment
    • …
    corecore