• Title/Summary/Keyword: Structure Equation Modelling

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Effects of environmental management on firm performance (환경경영이 경영성과에 미치는 영향에 관한 연구)

  • Kang, Min-Seok;Choi, Hyun-Seok;Park, Byung-Chun
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.3
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    • pp.523-536
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    • 2011
  • This study is to empirically investigate structural relations and the degree of effects among environmental strategy, environmental management system, environmental activities, and firm performance by using structural equation modelling. In particular, we focus on examining how the structure and the effect vary according to the type of environmental strategies. In this study, environmental strategies are classified as "passive type" and "active type" by the cluster analysis, which are used for developing two different research models. For firms employing active environmental strategy, the environmental strategy has a positive effect on all of environmental management system, environmental activities, and firm performance. For firms employing passive environmental strategy, the environmental strategy has a positive effect on both of environmental management system and environmental activities, while it does not have a statistically significant effect on firm performance. The study empirically supports that the active environmental management will result in a positive firm performance.

A Study on the Relationship between organizational commitment market orientation and organizational learning (조직몰입, 시장지향성, 조직학습의 관계에 관한 실증연구)

  • Chung, Ki-Han;Kim, Dae-Up
    • Journal of Global Scholars of Marketing Science
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    • v.10
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    • pp.139-164
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    • 2002
  • Market orientation emphasizes the capability of a firm to learn customers, competitors, and inter-functional coordination and to use this market intelligence of creating superior value in the marketplace. In recent years, academic and practitioner interest has focused on market orientation and factors that engender this orientation in organizations. Although the merits of maintaining organizational learning have been extensively discussed in the literature, little studies examine the empirical link between market orientation and organizational learning which has a strong relation with it. The objective of this study is to assess the relationship between organizational commitment, market orientation, and organizational learning and presents more close a relational structure. The relationships between organizational commitment(OC), market orientation (MO), and organizational learning(OL) were analysed by structural equation modelling. a structure of OC-MO-OL is supported by our research and past literatures.

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Analysis and Modelling of Vibration Performance for Multi-layered Corrugated Structure

  • Kim, Jin Nyul;Sim, Jae Min;Park, Min Jung;Kim, Ghi Seok;Kim, Jongsoon;Park, Jong Min
    • Journal of Biosystems Engineering
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    • v.38 no.4
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    • pp.327-334
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    • 2013
  • Purpose: The purpose of this study was to analyze for resonant frequency, vibration transmissibility and damping ratio of multi-layered corrugated structures using a random vibration test. Methods: The random vibration test was performed by the ASTM D4728 specifications using two paperboards (S120, K180) and two types of flutes (A/F, B/F). Damping ratio of the multi-layered corrugated structures was estimated using a theoretical equation derived from the measured resonant frequency and transmissibility. Results: The resonant frequency and vibration transmissibility of the multi-layered corrugated structures of K180 and B-flute were higher than those of S120 and A-flute, respectively; however, the damping ratio of each sample had the opposite tendency. The resonant frequency was inversely proportional to the sample thickness and static stress; vibration transmissibility and damping ratio were not correlated with sample thickness and static stress. In addition, we developed a mathematical model of the resonant frequency with variables of sample thickness and static stress. Conclusions: Results of this study can be useful for environment-friendly and optimal packaging design since vibration has been a key factor in cushioning packaging design.

Numerical Study of Hybrid Base-isolator with Magnetorheological Damper and Friction Pendulum System (MR 감쇠기와 FPS를 이용한 하이브리드 면진장치의 수치해석적 연구)

  • Kim, Hyun-Su;Roschke, P.N.
    • Journal of the Earthquake Engineering Society of Korea
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    • v.9 no.2 s.42
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    • pp.7-15
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    • 2005
  • Numerical analysis model is proposed to predict the dynamic behavior of a single-degree-of-freedom structure that is equipped with hybrid base isolation system. Hybrid base isolation system is composed of friction pendulum systems (FPS) and a magnetorheological (MR) damper. A neuro-fuzzy model is used to represent dynamic behavior of the MR damper. Fuzzy model of the MR damper is trained by ANFIS (Adaptive Neuro-Fuzzy Inference System) using various displacement, velocity, and voltage combinations that are obtained from a series of performance tests. Modelling of the FPS is carried out with a nonlinear analytical equation that is derived in this study and neuro-fuzzy training. Fuzzy logic controller is employed to control the command voltage that is sent to MR damper. The dynamic responses of experimental structure subjected to various earthquake excitations are compared with numerically simulated results using neuro-fuzzy modeling method. Numerical simulation using neuro-fuzzy models of the MR damper and FPS predict response of the hybrid base isolation system very well.

Physical Modelling for Consistent Reasonable Thought and Stock-Price Flow Patterns (합리적 생각의 물리적 모델링과 주가 흐름 패턴 분석)

  • Park, Sangup
    • New Physics: Sae Mulli
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    • v.68 no.12
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    • pp.1364-1373
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    • 2018
  • A recognizable form having meaning is called a sign in semiotics. The sign is transformed into a physical counter form in this work. Its internal structure is restricted on the linguistic concept structure. We borrow the concept of a mathematical function from the utility function of a rational personal in the economy. Universalizing the utility function by introducing the consistency of independency on the manner of construction, we construct the probability. We introduce a random variable for the probability and join it to a position variable. Thus, we propose a physical sign and its serial changes in the forms of stochastic equations. The equations estimate three patterns (jumping, drifting, diffusing) of possible solutions, and we find them in the one-day stock-price flow. The periods of jumping, drifting and diffusing were about 2, 3.5, and 6 minutes for the Kia stock on 11/05/2014. Also, the semiotic sign (icon, index, symbol) can be expected from the equations.

An efficient 2.5D inversion of loop-loop electromagnetic data (루프-루프 전자탐사자료의 효과적인 2.5차원 역산)

  • Song, Yoon-Ho;Kim, Jung-Ho
    • Geophysics and Geophysical Exploration
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    • v.11 no.1
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    • pp.68-77
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    • 2008
  • We have developed an inversion algorithm for loop-loop electromagnetic (EM) data, based on the localised non-linear or extended Born approximation to the solution of the 2.5D integral equation describing an EM scattering problem. Source and receiver configuration may be horizontal co-planar (HCP) or vertical co-planar (VCP). Both multi-frequency and multi-separation data can be incorporated. Our inversion code runs on a PC platform without heavy computational load. For the sake of stable and high-resolution performance of the inversion, we implemented an algorithm determining an optimum spatially varying Lagrangian multiplier as a function of sensitivity distribution, through parameter resolution matrix and Backus-Gilbert spread function analysis. Considering that the different source-receiver orientation characteristics cause inconsistent sensitivities to the resistivity structure in simultaneous inversion of HCP and VCP data, which affects the stability and resolution of the inversion result, we adapted a weighting scheme based on the variances of misfits between the measured and calculated datasets. The accuracy of the modelling code that we have developed has been proven over the frequency, conductivity, and geometric ranges typically used in a loop-loop EM system through comparison with 2.5D finite-element modelling results. We first applied the inversion to synthetic data, from a model with resistive as well as conductive inhomogeneities embedded in a homogeneous half-space, to validate its performance. Applying the inversion to field data and comparing the result with that of dc resistivity data, we conclude that the newly developed algorithm provides a reasonable image of the subsurface.

Stochastic Modelling of Monthly flows for Somjin river (섬진강 월유출량의 추계학적 모형)

  • 이종남;이홍근
    • Water for future
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    • v.17 no.4
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    • pp.281-291
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    • 1984
  • In our Koreans river basins there are many of monthly rainfall data, but unfortrnately streamflow data needed are rare. Analysing monthly rainfall data of Somjin river basin, the stochastic theory model for calculation of monthly streamflow series of that region is determined. The model is composed of Box & Jenkins stansfer function plus ARIMA residual models. This linear stochastic differenced time series equation models can adapt themselves to the structure and variety of rainfall, streamflow data on the assumption of the stationary covarience. The fiexibility of Box-Jenkins method consists mainly in the iterative technique of building an AIRMA model from observations and by the use of autocorrelation functions. The best models for Somjin river basin belong to the general calss: $Y_t=($\omega$o-$\omega$_1B) C_iX_t+$\varepsilon$t$ $Y_t$ monthly streamflow, $X_t$ : monthly rainfall, $C_i$ :monthly run-off, $$\omega$o-$\omega$_1$ : transfer parameter, $$\varepsilon$_t$ : residual The streamflow series resulted from the proposed model is satisfactory comparing with the exsting streamflow data of Somjin gauging station site.

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A Study on the Effects of Emotional Labor on Counterproductive Work Behavior: Mediated by Job Satisfaction and Organizational Commitment (감정노동이 반생산적 과업행동에 미치는 영향에 관한 연구: 직무만족과 조직몰입을 매개로)

  • Han, Na-Young;Bae, Sang-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.10
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    • pp.7157-7165
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    • 2015
  • This research conducted a survey of the workers in medical institutions and carried out empirical analysis through covariance structure equation modelling in order to examine the relationship among emotional labor, job satisfaction, organizational commitment, and counterproductive work behaviors of medical institution workers. The results of the empirical analysis are as follows; First, the frequency of emotional expression, one of the dimensions of emotional labor, did not have a positive influence on job satisfaction, but both the degree of emotional expression attentiveness and emotional dissonance had a negatively significant effect on job satisfaction. Second, job satisfaction had a positively significant effect on organizational commitment. Third, organizational commitment had a negatively significant effect on counterproductive work behaviors toward both individuals and organizations. This research result shows that it is necessary to pay attention to drawing a plan to reduce emotional labor that workers in medical institutions experience since emotional labor causes them to get negative results while they are performing their duties.

Numerical Study on the Observational Error of Sea-Surface Winds at leodo Ocean Research Station (수치해석을 이용한 이어도 종합해양과학기지의 해상풍 관측 오차 연구)

  • Yim Jin-Woo;Lee Kyung-Rok;Shim Jae-Seol;Kim Chong-Am
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.18 no.3
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    • pp.189-197
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    • 2006
  • The influence of leodo Ocean Research Station structure to surrounding atmospheric flow is carefully investigated using CFD techniques. Moreover, the validation works of computational results are performed by the comparison with the observed data of leodo Ocean Research station. In this paper, we performed 3-dimensional CAD modelling of the station, generated the grid system for numerical analysis and carried out flow analyses using Navier-Stokes equations coupled with two-equation turbulence model. For suitable free stream conditions of wind speed and direction, the interference of the research station structure on the flow field is predicted. Beside, the computational results are benchmarked by observed data to confirm the accuracy of measured date and reliable data range of each measuring position according to the wind direction. Through the results of this research, now the quantitative evaluation of the error range of interfered gauge data is possible, which is expected to be applied to provide base data of accurate sea surface wind around research stations.

Propagation characteristics of blast-induced vibration to fractured zone (파쇄영역에 따른 발파진동 전파특성)

  • Ahn, Jae-Kwang;Park, Duhee;Park, Ki-Chun;Yoon, Ji Nam
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.6
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    • pp.959-972
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    • 2017
  • In evaluation of blast-induced vibration, peak particle velocity (PPV) is generally calculated by using attenuation relation curve. Calculated velocity is compared with the value in legal requirements or the standards to determine the stability. Attenuation relation curve varies depending on frequency of test blasting, geological structure of the site and blasting condition, so it is difficult to predict accurately using such an equation. Since PPV is response value from the ground, direct evaluation of the structure is impractical. Because of such a limit, engineers tend to use the commercial numerical analysis program in evaluating the stability of the structure more accurately. However, when simulate the explosion process using existing numerical analysis program, it's never easy to accurately simulate the complex conditions (fracture, crushing, cracks and plastic deformation) around blasting hole. For simulating such a process, the range for modelling will be limited due to the maximum node count and it requires extended calculation time as well. Thus, this study is intended to simulate the elastic energy after fractured zone only, instead of simulating the complex conditions of the rock that results from the blast, and the analysis of response characteristics of the velocity depending on shape and size of the fractured zone was conducted. As a result, difference in velocity and attenuation character were calculated depending on fractured zone around the blast source appeared. Propagation of vibration tended to spread spherically as it is distanced farther from the blast source.