• 제목/요약/키워드: second-order system

검색결과 3,286건 처리시간 0.035초

A Study on the Improvement of Resolution of Optical Coherence Tomography System Using Femto-Second Laser (펨토초 레이저를 이용한 OCT 시스템의 분해능 향상에 관한 연구)

  • Yang, Sung-Kuk;Park, Yang-Ha;Chang, Won-Suk;Oh, Sang-Ki;Kim, Hyun-Duk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • 제18권6호
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    • pp.31-36
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    • 2004
  • Optical coherence tomography system has been extensively studied because it has some advantages such as imaging of high resolution, low cost, and compact size configuration. In order to obtain high resolution of OCT system we configured OCT system using a femto-second laser. We measure the pulse width using autocorrelator function because a femto-second laser is ultra short pulse. And we measured the practical resolution using theoretical equation and the measurement of reference sample. It is confirmed that the proposed OCT system has 1.5 times higher resolution and un distinctive cross-sectional image than OCT system with SLD as a light source.

A Study on the Settlement of Local Government Accounting System (정부의 복식회계제도 정착에 관한 연구)

  • Park Lee-Bong
    • Management & Information Systems Review
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    • 제12권
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    • pp.161-179
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    • 2003
  • The purpose of this study is to settle local government accounting system. In order to achieve this object. First, accural accounting should be closely connected with budgetary accounting. Second, a computerized program for double entry book-keeping system must be developed primarily. Finally, the improvement of local government accounting system should be oriented enhancing efficiency and public accountability.

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Reduction Characteristics of Triclosan using Zero-valent Iron and Modified Zero-valent Iron (영가철 및 개질 영가철을 이용한 triclosan의 환원분해 특성)

  • Choi, Jeong-Hak;Kim, Young-Hun
    • Journal of Environmental Science International
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    • 제26권7호
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    • pp.859-868
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    • 2017
  • In this study, the reductive dechlorination of triclosan using zero-valent iron (ZVI, $Fe^0$) and modified zero-valent iron (i.e., acid-washed iron (Aw/Fe) and palladium-coated iron (Pd/Fe)) was experimentally investigated, and the reduction characteristics were evaluated by analyzing the reaction kinetics. Triclosan could be reductively decomposed using zero-valent iron. The degradation rates of triclosan were about 50% and 67% when $Fe^0$ and Aw/Fe were used as reductants, respectively, after 8 h of reaction. For the Pd/Fe system, the degradation rate was about 57% after 1 h of reaction. Thus, Pd/Fe exhibited remarkable performance in the reductive degradation of triclosan. Several dechlorinated intermediates were predicted by GC-MS spectrum, and 2-phenoxyphenol was detected as the by-product of the decomposition reaction of triclosan, indicating that reductive dechlorination occurred continuously. As the reaction proceeded, the pH of the solution increased steadily; the pH increase for the Pd/Fe system was smaller than that for the $Fe^0$ and Aw/Fe system. Further, zero-order, first-order, and second-order kinetic models were used to analyze the reaction kinetics. The first-order kinetic model was found to be the best with good correlation for the $Fe^0$ and Aw/Fe system. However, for the Pd/Fe system, the experimental data were evaluated to be well fitted to the second-order kinetic model. The reaction rate constants (k) were in the order of Pd/Fe > Aw/Fe > $Fe^0$, with the rate constant of Pd/Fe being much higher than that of the other two reductants.

Stochastic thermo-mechanically induced post buckling response of elastically supported nanotube-reinforced composite beam

  • Chaudhari, Virendra Kumar;Shegokar, Niranjan L.;Lal, Achchhe
    • Advances in aircraft and spacecraft science
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    • 제4권5호
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    • pp.585-611
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    • 2017
  • This article covenants with the post buckling witticism of carbon nanotube reinforced composite (CNTRC) beam supported with an elastic foundation in thermal atmospheres with arbitrary assumed random system properties. The arbitrary assumed random system properties are be modeled as uncorrelated Gaussian random input variables. Unvaryingly distributed (UD) and functionally graded (FG) distributions of the carbon nanotube are deliberated. The material belongings of CNTRC beam are presumed to be graded in the beam depth way and appraised through a micromechanical exemplary. The basic equations of a CNTRC beam are imitative constructed on a higher order shear deformation beam (HSDT) theory with von-Karman type nonlinearity. The beam is supported by two parameters Pasternak elastic foundation with Winkler cubic nonlinearity. The thermal dominance is involved in the material properties of CNTRC beam is foreseen to be temperature dependent (TD). The first and second order perturbation method (SOPT) and Monte Carlo sampling (MCS) by way of CO nonlinear finite element method (FEM) through direct iterative way are offered to observe the mean, coefficient of variation (COV) and probability distribution function (PDF) of critical post buckling load. Archetypal outcomes are presented for the volume fraction of CNTRC, slenderness ratios, boundary conditions, underpinning parameters, amplitude ratios, temperature reliant and sovereign random material properties with arbitrary system properties. The present defined tactic is corroborated with the results available in the literature and by employing MCS.

Transporter Operation Planning for Refrigerated Warehouse Using Simulation Method (냉장물류센터 내 운반장비 운영계획에 관한 연구)

  • Hwang, Heung-Suk;Kim, Ho-Gyun;Cho, Gyu-Sung
    • IE interfaces
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    • 제15권4호
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    • pp.382-390
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    • 2002
  • This paper deals with planning of order-picking warehouse considering the batch order picking for transportation equipments to pick consumers' orders at a time among order-picking methods and a systematic approach method in order to analyze the order-picking warehouse which can perform optimal operation. To estimate an operating time of transportation equipments to carry out order-picking, this paper suggests three operations : first, to design the refrigerated warehouse using warehouse design parameters, second, to calculate the travel time of transporters considering four types of times with the probabilistic picking frequency, and third, to analyze an order-picking warehouse to construct a simulation model with the AutoMod as a simulation tool. We apply this model to a refrigerated warehouse company in Busan.

SEMI-ANALYTICAL SOLUTION TO A COUPLED LINEAR INCOMMENSURATE SYSTEM OF FRACTIONAL DIFFERENTIAL EQUATIONS

  • Iqbal M. Batiha;Nashat Alamarat;Shameseddin Alshorm;O. Y. Ababneh;Shaher Momani
    • Nonlinear Functional Analysis and Applications
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    • 제28권2호
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    • pp.449-471
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    • 2023
  • In this paper, we study a linear system of homogeneous commensurate /incommensurate fractional-order differential equations by developing a new semi-analytical scheme. In particular, by decoupling the system into two fractional-order differential equations, so that the first equation of order (δ + γ), while the second equation depends on the solution for the first equation, we have solved the under consideration system, where 0 < δ, γ ≤ 1. With the help of using the Adomian decomposition method (ADM), we obtain the general solution. The efficiency of this method is verified by solving several numerical examples.

A Study of Cross-border Trade in Second-hand Goods

  • Lee, Eun-Sook;Lee, Kwang-keun
    • Journal of Distribution Science
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    • 제11권11호
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    • pp.89-99
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    • 2013
  • Purpose - The purpose of this research was to examine the regulation and distribution channel of second-hand goods in cross-border trade in order to propose methods of protecting consumers through the international standardization of the intensifying second-hand trade and resource recycling. Research design, data, methodology - This study first defines several concepts relevant to research in international second-hand goods. Second, a questionnaire and interviews were conducted with manufacturers of second-hand toner cartridges and automobile parts to identify the current status of export and manufacturing. Results - The study proposes the international standardization of second-hand goods and waste to protect consumers and promote efficient resource recycling. Conclusions - The results of the study reveal that second-hand goods (except automobiles) do not have an HSK code to use for import/export data collection. Though used car exports are declining, used cars are increasing. Collecting data on used car parts is impossible because the buyers purchase and ship the second-hand parts.

Chaos in PID Controlled Nonlinear Systems

  • Ablay, Gunyaz
    • Journal of Electrical Engineering and Technology
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    • 제10권4호
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    • pp.1843-1850
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    • 2015
  • Controlling nonlinear systems with linear feedback control methods can lead to chaotic behaviors. Order increase in system dynamics due to integral control and control parameter variations in PID controlled nonlinear systems are studied for possible chaos regions in the closed-loop system dynamics. The Lur’e form of the feedback systems are analyzed with Routh’s stability criterion and describing function analysis for chaos prediction. Several novel chaotic systems are generated from second-order nonlinear systems including the simplest continuous-time chaotic system. Analytical and numerical results are provided to verify the existence of the chaotic dynamics.

Analysis and Measurement of Performance Factors of HIS (병원정보시스템의 성과측정을 위한 측정 요인 도출 및 중요도 분석)

  • Gi, Hong-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제11권11호
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    • pp.4207-4211
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    • 2010
  • The goal of this paper is to set up the order list of performance measurement factors according to the its weights. For this purpose the AHP method were implied. The research of this paper is carried out in two steps. At first step, the performance measurement factors are crystallized through review of the korean and foreign researches. In second step, the weights and order list of critical success factors of Hospital Information System were complete. The AHP method were performed in second step. The order list of all CSFs will be determined according to their weights and priorities. This order list shows which factors have the most useful influence on the performance of HIS. This result could play the role as milestone for the effective management of Hospital Information System in Korea.

An Analysis on the Stability for Pylon Types of Cable-Stayed Bridge (사장교 주탑 형상에 따른 안정해석)

  • 임정열;윤영만;안주옥
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 한국전산구조공학회 2000년도 봄 학술발표회논문집
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    • pp.246-252
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    • 2000
  • The nonlinearity of a cable-stayed bridge results in the large displacement of main girder due to a long span, the large axial forces reduce the catenary action of cables and the flexural stiffness. Therefore, the static and dynamic behavior of pylon for a cable-stayed bridge plays an important role in determining its safety. This study was performed to find the behavior of pylon of cable-stayed bridge for the first-order analysis considering of axial load only and for the second-order analysis considering of lateral deflection due to axial load. The axial force and moment values of pylon were different from the results of the first-order analysis and second-order analysis according to pylon shape and cross beam stiffness when the pylon was subjected to earthquake and wind loads. In the second-order analysis, comparing the numerical values of the member forces for the dynamic analysis, types 3 and 4 (A type) were relatively more advantageons types than types 1 and 2 (H type). Considering the stability for pylon of cable-stayed bridge (whole structural system), types 3 and 4 (A type) with pre-buckling of girder were proper types than types 1 and 2 (H type) with buckling of pylon.

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