• Title/Summary/Keyword: data modelling

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Effect of thermal conductivity degradation on the behavior of high burnup $UO_2$ fuel

  • Lee, Byung-Ho;Koo, Yang-Hyun;Sohn, Dong-Seong
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05c
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    • pp.265-270
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    • 1996
  • The temperature distribution in the pellet was obtained from beginning the general heat conduction equation. The thermal conductivity of pellet used the SIMFUEL data that made clear the effect of burnup on the thermal conductivity degradation. Since the pellet rim acts as the thermal barrier to heat flow. the pellet was subdivided into several rings in which the outer ring was adjusted to play almost the same role as the rim. The local burup in each ring except the outer ring was calculated from the power depression factor based on FASER results. whereas the rim burnup at the outer ring was achieved by the pellet averaged burnup based on the empirical relation. The rim changed to the equivalent Xe film so the predicted temperature shooed the thermal jump across the rim. The observed temperature profiles depended on linear heat generation rate. fuel burnup. and power depression factor. The thermal conductivity degradation modelling can be applied to the fuel performance code to high burnup fuel,

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Analysis of Hydraulic Characteristics using SMS RMA2 and SED2D Model in the Downstream of Gyeongan-Cheon (SMS를 이용한 경안천 하류구간의 하천흐름 분석)

  • Hong, Seong-Min;Jung, In-Kyun;Kim, Seong-Joon
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.519-522
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    • 2003
  • The purpose of this study is to analyze various hydraulic characteristics using SMS (Surface Water Modelling System) RMA2 model. It is based on 2-D finite element method. River reaches (13.8km) from Gyeongan gauge station to the inlet of Paldang lake was selected. Finite element was made by RIMGIS Data, and the analysis of river-changes was operated by unsteady flow. The sediment concentration and bed change was simulated using SED2D model.

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A Study of Radio Wave Propagation Characteristics at 900MHz Range for Urban Modelling (도시형 모델링을 위한 900MHz대 전파전파 특성에 대한 연구(I))

  • 남채우;박성교박종백
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.165-168
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    • 1998
  • This paper describes the characteristics of CT-2 radio wave propagation at 900MHz range. Typical cell coverage of CT-2 based on picocellular design provides a 200m radius. The five sites of urban regions of Kwang Ju city were chosen to characterize propagation in various environments. On the basis of cell coverage data measured with field strength meter, average 75% of telepoint service was retained and it was lack 25% of overall gain. In some sites telepoint service was limited to two of four directions around a station. If specially designed collinear antenna with specific directivities are used in these shadow area, improved results will be acquired.

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The uncertainty problem analysis of the engineering solution for prediction and estimation of the operating regime to design of gas- hydro-dynamic systems

  • Kartovitskiy, Lev;Tsipenko, Anton;Lee, Ji-Hyung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.11a
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    • pp.459-468
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    • 2009
  • Analysis of the uncertainty to have engineering solution of gas-dynamic and hydrodynamic problems is based on the comparison the prospective engineering solution with experimental result. In this paper, the mathematical model to estimate heat flux along gas-dynamic channel wall and the solution sequence are shown. Statistical information and generalizing experimental characteristics about gas- and hydro-dynamic channels were applied to the mathematical model. As the results, it is possible to draw a conclusion that models of the integrated approach, using the averaged statistical data of generalizing characteristics for a turbulent flow, without consideration of the turbulent mechanism (characteristic pulsations), can predict a nominal operating regime for gas-dynamic and hydrodynamic systems. The probable deviation of operating regime for newly designed the gas-dynamic channel can achieve 20% from a regime predicted on a basis 1-D or 3-D modelling irrespective of a kind of used models.

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Buckling behaviour of plates partially restrained against rotation under stress gradient

  • Bedair, Osama K.
    • Structural Engineering and Mechanics
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    • v.4 no.4
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    • pp.383-396
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    • 1996
  • In this paper, the behavior of plates partially restrained against rotation under stress gradient is investigated. As a first stage, an energy formulation is presented to model this boundary condition and a general expression is derived for the prediction of the elastic buckling of the plate under this general loading condition. The accuracy of the derived expression is compared numerically using the Galerkin method with other available data for the two limiting conditions of rotationally free and clamped boundaries. Results show that the prediction is within a 5% difference. The influence of rotational restraint and stress gradient upon the buckling load and the associated buckling mode is investigated. Numerical results show sensitivity of the buckling mode to the degree of rotational restraint and the variation of the buckling load with the stress gradient.

Understanding Abusive Supervision: The Impacts of Abusive Supervision on Employees' Engagement and Organizational Commitment in the Deluxe Hotel

  • Jung, Hyo Sun;Kim, Ki-bbeum;Yoon, Hye Hyun
    • Culinary science and hospitality research
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    • v.24 no.2
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    • pp.8-15
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    • 2018
  • This study examines the effect of abusive supervision on employees' engagement and commitment in the deluxe hotel. Based on total 272 hotel employees obtained from the empirical research, this study verified total 3 hypotheses. The hypothesized relationships in the model were tested simultaneously by using structural equation modelling. Abusive supervision perceived by employees had negative effect on engagement and employees' engagement had positive effect on organizational commitment. Also, abusive supervision perceived by employees did not have a significant effect on organizational commitment, full mediation effect through engagement existed. The study results are expected to be used as data for searching for effective responding ways at an organizational level and find practical ways to further increase employees' positive organizational behavior.

Self-Tuning Position Control of a Remotely Operated Vehicle (원격무인 잠수정의 자기동조 위치제어)

  • Lee, Pan-Muk
    • Journal of Ocean Engineering and Technology
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    • v.3 no.2
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    • pp.551-551
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    • 1989
  • In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

Self-Tuning Position Control of a Remotely Operated Vehicle (원격무인 잠수정의 자기동조 위치제어)

  • Lee, Pan-Muk
    • Journal of Ocean Engineering and Technology
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    • v.3 no.2
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    • pp.51-58
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    • 1989
  • In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

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A Design on Model Following Nonlinear Control System Using GMDH (GMDH 기법에 의한 모델추종형 비선형 제어시스템 구성에 관한 연구)

  • Hwang, C.S.;Kim, M.S.;Kim, D.W.;Lee, K.H.;Shim, J.S.
    • Proceedings of the KIEE Conference
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    • 1993.11a
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    • pp.326-328
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    • 1993
  • Modelling theory, based on differential equations, is not an adequate tool for solving the problems of complex system. Identification of complex system using GMDH(group method of data handling) is more appropriate for this problems. In this paper, GMDH algorithm is used to identify the nonlinear plant and to design model following nonlinear control system. Simulation for the DC motor show the good performance of model following nonlinear control system.

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Brand Credibility and Brand Involvement as an antecedent of Brand Equity: An Empirical Study

  • Rao, Roopesh
    • Asia-Pacific Journal of Business
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    • v.3 no.1
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    • pp.17-28
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    • 2012
  • Very few studies have been done on Studying Brand credibility and Involvement as a determinant of Brand Equity. Literature on Brand Equity signifies lots of constructs like, Country of Origin, Brand Signaling, and Brand Power act as determinant to Brand Equity. This study tries to formulate relationship between the construct Brand Credibility and Brand Involvement as Antecedents to Brand Equity of Product. Using a Two Step Structural Equation Modelling approach analysis on the data collected on Mobile Phone brands were done. Result signified that Brand Credibility and Brand Involvement had significant influence on Brand Equity of the Product. On the Other hand there was no significant relationship between Brand Credibility and Brand Involvement of the Product.

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