• Title/Summary/Keyword: measurement and modeling

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Testing for Measurement Invariance of Fashion Brand Equity (패션브랜드 자산 측정모델의 등치테스트에 관한 연구)

  • Kim Haejung;Lim Sook Ja;Crutsinger Christy;Knight Dee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.12 s.138
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    • pp.1583-1595
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    • 2004
  • Simon and Sullivan(l993) estimated that clothing and textile related brand equity had the highest magnitude comparing any other industry category. It reflects that fashion brands reinforce the symbolic, social values and emotional characteristics being different from generic brands. Recently, Kim and Lim(2002) developed a fashion brand equity scale to measure a brand's psychometric properties. However, they suggested that additional psychometric tests were needed to compare the relative magnitude of each brand's equity. The purpose of this study was to recognize the psychometric constructs of fashion brand equity and validate Kim and Lim's fashion brand equity scale using the measurement invariance test of cross-group comparison. First, we identified the constructs of fashion brand equity using confirmatory factor analysis through structural equation modeling. Second, we compared the relative magnitude of two brands' equity using the measurement invariance test of multi-group simultaneous factor analysis. Data were collected at six major universities in Seoul, Korea. There were 696 usable surveys for data analysis. The results showed that fashion brand equity was comprised of 16 items representing six dimensions: customer-brand resonance, customer feeling, customer judgment, brand imagery, brand performance and brand awareness. Also, we could support the measurement invariance of two brands' equities by configural and metric invariance tests. There were significant differences in five constructs' mean values. The greatest difference was in customer feeling; the smallest, in customer judgment.

Flow Analysis of Parshall Flume Using FLOW-3D (FLOW-3D에 의한 파샬플륨 흐름 해석)

  • Oh, Byoung-Dong;Kim, Kyoung-Ho;Lee, Whan-Gi;An, Sang-Do
    • Journal of Korea Water Resources Association
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    • v.37 no.5
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    • pp.375-386
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    • 2004
  • A water shortage is one of the most important factors for development and management of water resources. For reliable water shortage measurement in a stream, Korea Water Resources Corporation(KOWACO) founded five foot Parshall flume at Yong-dam experimental watershed in 2000. The Parshall flume has a specially designed shape to facilitate flow measurements by eliminating sediment deposition problem that could lead to an incorrect measurement. In this study, computational fluid dynamics(CFD) model was used to analyze flow behavior of Parshall Flume under free discharge of five headwater level cases. The flow rates computed by CFD model are compared with those by ISO's formula, USBR's formula and stage-discharge rating curves. Flow rates computed by ISO's and USBR's formula are mostly same, but flow rate by CFD model is larger than empirical value by 9% and flow rate by stage-discharge rating curves is less than empirical value by 16%.

BIM-based visualization technology for blasting in Underground Space (지하공간 BIM 기반 발파진동 영향 시각화 기술)

  • Myoung Bae Seo;Soo Mi Choi;Seong Jong Oh;Seong Uk Kim;Jeong Hoon Shin
    • Smart Media Journal
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    • v.12 no.11
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    • pp.67-76
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    • 2023
  • We propose a visualization method to respond to civil complaints through an analysis of the impact of blasting. In order to analyze the impact of blasting on tunnel excavation, we propose a simulation visualization method considering the mutual influence of the construction infrastructure by linking measurement data and 3D BIM model. First, the level of BIM modeling required for simulation was defined. In addition, vibration measurement data were collected for the GTX-A construction site, terrain and structure BIM were created, and a method for visualizing measurement data using blast vibration estimation was developed. Next, a spherical blasting influence source library was developed for visualization of the blasting influence source, and a specification table that could be linked with Revit Dynamo automation logic was constructed. Using this result, a method for easily visualizing the impact analysis of blasting vibration in 3D was proposed.

Network Modeling and Circuit Characteristics of Aperture-Coupled Vertically Mounted Strip Antenna

  • Kim, Jeong-Phill
    • Journal of electromagnetic engineering and science
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    • v.11 no.2
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    • pp.122-127
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    • 2011
  • A general analysis of an aperture-coupled vertically mounted strip antenna is presented to examine its circuit characteristics. Based on the present analysis, an equivalent circuit model is developed, and an analytic or semi-analytic evaluation of the related circuit element values is described. The effects of structure parameters on the antenna characteristics were studied with the developed equivalent circuit, and the design curves were obtained. To check the validity of the proposed analysis and design theory, two C-band antennas (5.0 GHz and 4.5 GHz) were designed and fabricated. Their computed characteristics, derived from the proposed network analysis, were compared with the measurement and simulation results. The error of the current model in predicting the operating center frequency was less than 0.50 %. In addition, the observed bandwidth was found to be comparable to the conventional microstrip antennas. All the results fully validated the efficiency and accuracy of the proposed analysis and network model.

Analysis of PD pulse propagation characteristic in GIS (GIS 내부의 부분방전 전파특성 해석)

  • Park, Kyoung-Su;Kim, Jin;Lee, Hee-Bock;Lim, Young-Hwan;Ko, Young-Ho
    • Proceedings of the KIEE Conference
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    • 2000.11c
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    • pp.534-536
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    • 2000
  • In this paper, propagation and damping characteristics of PD Pulse in GIS are analyzed using SNM. These characteristics are very important to make a diagnosis and protection of accident in GIS. SNM is numerical method in time domain and very useful method to analyze 3-Dimensional structure such as GIS. GIS modeling is made simply as the form of coaxial cable and then spacers are inserted in it. The scattering and reflection in the GIS are appeared and damping characteristics of PD pulse are shown. When simulation using SNM compare to measurement, two results are similar.

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A Novel Modeling and Performance Analysis of Imperfect Quadrature Modulator in RF Transmitter

  • Park, Yong-Kuk;Kim, Hyeong-Seok;Lee, Ki-Sik
    • Journal of Electrical Engineering and Technology
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    • v.7 no.4
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    • pp.570-575
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    • 2012
  • In a wireless communication RF transmitter, the output of a quadrature modulator (QM) is distorted by not only the linear imperfection features such as in/quadrature-phase (I/Q) input gain imbalance, local phase imbalance, and local gain imbalance but also the nonlinear imperfection features such as direct current (DC) offset and mixer nonlinearity related to in-band spurious signal. In this paper, we propose the unified QM model to analyze the combined effects of the linear and nonlinear imperfection features on the performance of the QM. The unified QM model consists of two identical nonlinear systems and modified I/Q inputs based on the two-port nonlinear mixer model. The unified QM model shows that the output signals can be expressed by mixer circuit parameters such as intercept point and gain as well as the imperfection features. The proposed approach is validated by not only simulation but also measurement.

A simple practical method for determination of moisture transfer coefficient of mature concrete using a combined experimental-numerical approach

  • Chari, Mehdi Nemati;Shekarchi, Mohammad;Ghods, Pouria;Moradian, Masoud
    • Computers and Concrete
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    • v.18 no.3
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    • pp.367-388
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    • 2016
  • In this paper, a simple practical method is introduced in which a simple weight measurement of concrete and finite element numerical analysis are used to determine the moisture transfer coefficient of concrete with a satisfactory accuracy. Six concrete mixtures with different water-to-cementitious material (w/cm) ratios and two pozzolanic materials including silica fume and zeolite were examined to validate the proposed method. The comparison between the distribution of the moisture content obtained from the model and the one from the experimental data during both the wetting and drying process properly validated the performance of the method.With the proposed method, it was also shown that the concrete moisture transfer coefficient considerably depends on the pore water saturation degree. The use of pozzolanic materials and also lowering w/cm ratio increased the moisture transfer coefficient during the initial sorption, and then, it significantly decreased with an increase in the water saturation degree.

구조물의 진동해석에 의한 시스템 규명에 관한 연구

  • 현천성;이기형;정인성
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1992.04a
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    • pp.279-284
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    • 1992
  • This paper presents the theoretical development and qualitiative evaluation of a new concept in the mathematical modeling of dynamicstructures. We use both test data and analytical approximations to identify the parameters of an incomplete model. The model has the capability of prodicting the response of the points of interest on the structure over the frequency range of interest and can be used to predict the changes in natural frequencies and normal modes due to structural changes. The theory was tested by running simulated tests on a relatively simple structure, identifying the parameters of the incomplete model, and using this model to predict the effects on frequency and mode shapes of several mass and stiffness changes. The conditions of the test were varied by selecting different numbers of points of meansurement, varying the frequency range, and by including assumed measurement error. It is recommended that the theroetical development be continued and that applications to more complex structures be carried out in order todevelop a better understanding of the limitations and capabilites of the method. A successful, more definitive evaluation could lead to immediate practical applications.

Dynamic Model and P-PD Control based Flight Performance Evaluation for Hexa-Rotor Type UAV (헥사로터형 무인기의 모델링과 P-PD기반 비행성능평가)

  • Jin, Taeseok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.7
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    • pp.1074-1080
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    • 2015
  • In the last decades, the increasing interest in unmanned aerial vehicle(UAV) for military, surveillance, and rescue applications made necessary the development of flight control theory and body structure more and more efficient and fast. In this paper, we describe the design and performance of a prototype hexarotor UAV platform featuring an inertial measurement unit(IMU) based autonomous-flying for use in bluetooth communication environments. The proposed system comprises the construction of the test hexarotor platform, the implementation of an IMU, dynamic modeling and simulation in the hexarotor helicopter. Furthermore, the hexarotor helicopter with implemented IMU is connected with a micro controller unit(ARM-cortex) board. The P-PD control algorithm was used to control the hexarotor. We used the Matlab software to help us to tune the P-PD control parameters for quick response and minimizing the fluctuation. The control simulation and experiment on the real system are implemented in the test platform, evaluated and compared against each other.

Analyzing the Causal Relationship between Qualities, Satisfaction, and Trust in Public Services: an Intermediary Customer Perspective (공공서비스 중간고객의 품질, 만족, 신뢰의 인과모형 분석)

  • Rha, June-Young
    • Journal of Korean Society for Quality Management
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    • v.38 no.3
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    • pp.378-390
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    • 2010
  • From the perspective of employees working for public service agencies, we analyzed the causal relationship between service quality, relationship quality, design quality, customer satisfaction, and trust in public services. We conduct statistical analyses on the quality attributes we derived from a critical incident technique(CIT) analysis and build a measurement model, which has a second-order hierarchical structure. Survey data was collected from social work, childcare, and healthcare services. Using a structural equation modeling method, we identify a causal model and simultaneously estimate factor loadings and path coefficients. We find that all the quality dimensions are antecedents to satisfaction and then satisfaction precedes trust. The results show that service quality and design quality mediate in parallel the effect of relationship quality on satisfaction and both relationship and design qualities have stronger effects on satisfaction rather than service quality.