157 research outputs found

    A Study of SVC’s Impact Simulation and Analysis for Distance Protection Relay on Transmission Lines

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    This paper focuses on analyzing and evaluating impact of a Static Var Compensator (SVC) on the measured impedance at distance protection relay location on power transmission lines. The measured impedance at the relay location when a fault occurs on the line is determined by using voltage and current signals from voltage and current transformers at the relay and the type of fault occurred on the line. The MHO characteristic is applied to analyze impact of SVC on the distance protection relay. Based on the theory, the authors in this paper develop a simulation program on Matlab/Simulink software to analyze impact of SVC on the distance protection relay. In the power system model, it is supposed that the SVC is located at mid-point of the transmission line to study impact of SVC on the distance relay. The simulation results show that SVC will impact on the measured impedance at the relay when the fault occurs after the location of the SVC on the power transmission line

    Some Limitations of ASEAN Organization in 55 Years of Operation

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    Association of Southeast Asian Nations (English : Association of South East Asian Nations, abbreviated as ASEAN) is a political , economic , cultural and social organization of countries in the Southeast region. Ah . ASEAN has a land area of 4.46 million km², accounting for 3% of the total land area of the Earth , and has a population of about 600 million people, accounting for 8.8% of the world's population . The waters of ASEAN are three times as large as land. Over 55 years of establishment and development, this is considered the most successful regional organization on earth. However, when it comes to ASEAN, people often talk about achievements, in the framework of this article, we would like to give some opinions on its limitations, as a basis for recommendations for leaders of the organization in this study. Keywords:ASEAN, limit, learn about, 55 years DOI: 10.7176/JESD/13-24-06 Publication date: December 31st 202

    On the solutions of universal differential equation by noncommutative Picard-Vessiot theory

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    Basing on Picard-Vessiot theory of noncommutative differential equations and algebraic combinatorics on noncommutative formal series with holomorphic coefficients, various recursive constructions of sequences of grouplike series converging to solutions of universal differential equation are proposed. Basing on monoidal factorizations, these constructions intensively use diagonal series and various pairs of bases in duality, in concatenation-shuffle bialgebra and in a Loday's generalized bialgebra. As applications, the unique solution, satisfying asymptotic conditions, of Knizhnik-Zamolodchikov equations is provided by d\'evissage

    On The Global Renormalization and Regularization of Several Complex Variable Zeta Functions by Computer

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    This review concerns the resolution of a special case of Knizhnik-Zamolodchikov equations (KZ3KZ_3) using our recent results on combinatorial aspects of zeta functions on several variables and software on noncommutative symbolic computations. In particular, we describe the actual solution of (KZ3)(KZ_3) leading to the unique noncommutative series, ΦKZ\Phi_{KZ}, so-called Drinfel'd associator (or Drinfel'd series). Non-trivial expressions for series with rational coefficients, satisfying the same properties with ΦKZ\Phi_{KZ}, are also explicitly provided due to the algebraic structure and the singularity analysis of the polylogarithms and harmonic sums

    Families of eulerian functions involved in regularization of divergent polyzetas

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    Extending the Eulerian functions, we study their relationship with zeta function of several variables. In particular, starting with Weierstrass factorization theorem (and Newton-Girard identity) for the complex Gamma function, we are interested in the ratios of ζ(2k)/π2k\zeta(2k)/\pi^{2k} and their multiindexed generalization, we will obtain an analogue situation and draw some consequences about a structure of the algebra of polyzetas values, by means of some combinatorics of noncommutative rational series. The same combinatorial frameworks also allow to study the independence of a family of eulerian functions.Comment: preprin

    Presence of e-EDCs in surface water and effluents of pollution sources in Sai Gon and Dong Nai river basin

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    © 2016 This study aimed to assess the presence of estrogenic endocrine disrupting compounds (e-EDCs) including estriol, bisphenol A (BPA), atrazine (ATZ), octylphenol, octylphenol diethoxylate, octylphenol triethoxylate, nonylphenol, Nonylphenol triethoxylate (NPE3), nonylphenol diethoxylate (NPE2) and 17β-estradiol in: (i) Sai Gon and Dong Nai river waters which have been major raw water sources for drinking water supply for Ho Chi Minh City (HCMC) and neighbouring provinces, and (ii) water pollution sources located in their catchment basin. NPE3 and NPE2 were detected in most of the surface water samples. Concentrations of NPE3 were in a range of less than 5.9–235 ng L−1, whereas BPA was detected at significantly high concentrations in the dry season in canals in HCMC. In the upstream of Sai Gon and Dong Nai Rivers, ATZ concentrations were observed at water intake of water treatment plants served for HCMC water supply system. Similarly, high potential risk of NPE2 and NPE3 contamination at Phu Cuong Bridge near Hoa Phu water intake was identified. The significant correlation between NPE2, dissolved organic carbon and total nitrogen was found. Estrogenic equivalent or estrogenic activity of Sai Gon and Dong Nai Rivers was lower than those of the previous studies. Compared with other studies, e-EDCs of pollution in Sai Gon river basin were relatively low

    The Anatomical Numerical Measurement of Posterior Cruciate Ligament: A Vietnamese Cadaveric Study

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    BACKGROUND: The posterior cruciate ligament (PCL) is crucial to restrain the posterior translation of the tibia. Its anatomical structure is complex. A proper understanding of PCL anatomy may assist surgeon in reconstructing anatomically native PCL. AIM: To describe the anatomical numerical measurement of the PCL in Vietnamese adults. METHODS: Twenty-one fresh cadaveric knees were examined. The macroscopic details of the intra-articular PCL, the attachment of the anterolateral bundle (ALB), posteromedial bundles (PMB) to the femur and tibia were analysed. We used a digital camera to photograph the cadaveric specimens and used the ImageJ software to analyse the collected images. RESULTS: The ALB and PMB length were 35.5 ± 2.78 and 32.6 ± 2.28 mm, respectively. The smallest and the biggest diameter of middle third of the PCL were 5.9 ± 0.71 and 10.0 ± 1.39 mm, respectively. The area of cross section of middle third of the PCL was 53.6 ± 12.37 mm2. The femoral insertion area of ALB and PMB were 88.4 ± 16.89 and 43.5 ± 8.83 mm2, respectively. The distance from the central point of femoral ALB, PMB, and total PCL insertion to the Blumensaat line were 5.5 ± 0.91, 11.5 ± 1.98, and 7.6 ± 1.42 mm, respectively. The shortest distance from medial femoral cartilage rim to the central point of femoral ALB, PMB, and total PCL insertion were 7.0 ± 0.79, 7.3 ± 0.95, and 7.8 ± 1.73 mm, respectively. The tibial insertion area of ALB and PMB were 84.5 ± 12.52 and 47.8 ± 6.20 mm2 respectively. The shortest distance from the posterior cartilage corner of the medial tibial plateau to the central point of ALB, PMB, and total PCL insertion to tibia were 8.5 ± 1.02, 9.4 ± 1.11, and 8.3 ± 1.1 mm, respectively. The central point of tibial PCL insertion was 9.7±1.08 mm below cartilage plane of the medial tibial plateau. CONCLUSION: This study describes the detailed anatomical measurement of the PCL and its bundles in adults
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