• Title/Summary/Keyword: Empirical Comparative

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An Empirical Comparative Analysis Between Kano and Improved Kano Methods (Kano 품질속성 평가방법론들의 실증적 비교분석)

  • Yoon, Jae-Wook;Lee, Hee-Young
    • Journal of Korean Society for Quality Management
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    • v.37 no.4
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    • pp.31-42
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    • 2009
  • Various studies have been undertaken in order to effectively understand customer requirements. Kano proposed a dualistic approach, physical fulfillment and customer satisfaction, to differentiate Attractive, Must-be, One-dimensional quality attributes. As there were a few limitations on the Kano's method, researchers have proposed improved methods. However, there have been few empirical evidences that the improved methods are superior to the original Kano's method for identifying relevant quality attributes. The objective of this study is to provide a comparative study on Kano and improved Kanomethods based on empirical analysis of quality attributes on University services. For the analysis of the questionnaire formats, the Kano's original 5 scale questionnaire is more effective than improved methods, direct and 3 scale questionnaire. For the analysis of evaluation methods, the original Kano and Timko's method using the evaluation table are more effective than quantifying methods, Domouchel and Lim's methods.

A Comparative Study for Several Bayesian Estimators Under Balanced Loss Function

  • Kim, Yeong-Hwa
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.2
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    • pp.291-300
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    • 2006
  • In this research, the performance of widely used Bayesian estimators such as Bayes estimator, empirical Bayes estimator, constrained Bayes estimator and constrained empirical Bayes estimator are compared by means of a measurement under balanced loss function for the typical normal-normal situation. The proposed measurement is a weighted sum of the precisions of first and second moments. As a result, one can gets the criterion according to the size of prior variance against the population variance.

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A Comparative Study for Several Bayesian Estimators Under Squared Error Loss Function

  • Kim, Yeong-Hwa
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.2
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    • pp.371-382
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    • 2005
  • The paper compares the performance of some widely used Bayesian estimators such as Bayes estimator, empirical Bayes estimator, constrained Bayes estimator and constrained Bayes estimator by means of a new measurement under squared error loss function for the typical normal-normal situation. The proposed measurement is a weighted sum of the precisions of first and second moments. As a result, one can gets the criterion according to the size of prior variance against the population variance.

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Empirical Study on the Dip Design and Installation of Distribution Line Conductors (배전선로의 이도설계 및 시공에 대한 실증연구)

  • Ahn, Ihn-Seok
    • Journal of the Korean Society of Industry Convergence
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    • v.24 no.3
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    • pp.307-313
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    • 2021
  • In this study, the comparative analysis, among the design standard value of distribution power, the calculated value from the measurement data of strand and the empirical data of the distribution line itself, have been performed for the elastic coefficients and linear expansion coefficients of distribution line conductors. The empirical values of elastic coefficients were lower about 10.6%(892kgf/mm2) than those of the design standard value of the distribution power and there were a little difference between the empirical values of linear expansion coefficients and the design standard value of the distribution power. From the above results, it could be concluded that the empirical values of conductor characteristics should be used in the dip design and installation of distribution line.

A Comparative Study on the Performance of Bayesian Partially Linear Models

  • Woo, Yoonsung;Choi, Taeryon;Kim, Wooseok
    • Communications for Statistical Applications and Methods
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    • v.19 no.6
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    • pp.885-898
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    • 2012
  • In this paper, we consider Bayesian approaches to partially linear models, in which a regression function is represented by a semiparametric additive form of a parametric linear regression function and a nonparametric regression function. We make a comparative study on the performance of widely used Bayesian partially linear models in terms of empirical analysis. Specifically, we deal with three Bayesian methods to estimate the nonparametric regression function, one method using Fourier series representation, the other method based on Gaussian process regression approach, and the third method based on the smoothness of the function and differencing. We compare the numerical performance of three methods by the root mean squared error(RMSE). For empirical analysis, we consider synthetic data with simulation studies and real data application by fitting each of them with three Bayesian methods and comparing the RMSEs.

A Comparative Study of Ice Resistance Estimation Equations with Measured Data for Icebreakers and Ice-Strengthened Cargo Vessels (쇄빙선 및 쇄빙상선에 대한 빙저항 추정식과 실측자료의 비교 분석)

  • Choi, Kyung-Sik;Lee, Woo-Ram;Lee, Jin-Kyoung
    • Journal of the Society of Naval Architects of Korea
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    • v.43 no.2 s.146
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    • pp.147-155
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    • 2006
  • Ice resistance estimation equations based on model tests and full-scale sea trial data from many previous research articles are studied. Measured ice resistance data and its empirical/semi-empirical estimation equations are summarized in common format and are compared with each other, considering three ship categories, i.e, icebreakers, tug/supply vessels, ice-strengthened cargo vessels. The most suitable estimation methods or prediction equations are recommended based on this ice resistance data analysis.

Research of International Comparison about Ranging the Marines Protected Areas (MPA) (국가 해양보호구역 지정규모에 관한 국제비교 연구)

  • Duckhee, Jang;Changyoul, Lee;Eun-Young, Cho
    • Ocean and Polar Research
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    • v.44 no.4
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    • pp.339-353
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    • 2022
  • The purpose of this research is to conduct an empirical analysis regarding Korea's 'Marine Protected Areas (MPA)' from an international comparative perspective. The authors would like to present the policy direction of marine protected areas based on the result of the research. The result of this study can be summarized in the following manner: First, the total designated size of marine protected areas in Korea is very small compared to the sizes of other OECD nations . Second, while some nations have expanded the extent of marine protected areas in accordance with international agreements and criteria, Korea has not done so. Accordingly, we propose the designated dimensions of marine protected areas should be constantly expanded to keep pace with international trends.

A comparative analysis on research trends of statistics education between Korea and overseas (국내외 통계교육 연구동향 비교 분석)

  • Lee, Eun Hee;Kim, Won Kyung
    • The Mathematical Education
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    • v.54 no.3
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    • pp.241-259
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    • 2015
  • The purpose of this study is to analyze research trends and specific features in the statistics education between Korea and overseas. For this purpose, a total of 180 articles presented in 4 domestic and 4 foreign journals of the mathematics education and statistics education was investigated. The result findings are as follows. First, more than half of researches have been carried out in teaching and learning, understanding of statistical concepts in both of domestic and foreign journals. Second, some researches on the affective effect were carried out in foreign journals, but not in domestic journals. Third, researches on the teacher education were carried out mainly for the pre-service teachers in domestic journals, but mainly for the in-service teachers in foreign journals. Fourth, empirical study was mainly used for the research method in domestic journals while both empirical and non-empirical study were used in foreign journals. Fifth, subjects of research were mainly secondary students in domestic journals, but over undergraduate students in foreign journals.

An empirical model for amplitude prediction on VIV-galloping instability of rectangular cylinders

  • Niu, Huawei;Zhou, Shuai;Chen, Zhengqing;Hua, Xugang
    • Wind and Structures
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    • v.21 no.1
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    • pp.85-103
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    • 2015
  • Aerodynamic forces of vortex-induced vibration and galloping are going to be coupled when their onset velocities are close to each other, which will induce the cross-wind amplitudes of the structures increased continuously with ever-increasing wind velocities. The main purpose of the present work is going to propose an empirical formula to predict the response amplitude of VIV-galloping interaction. Firstly, two typical mathematical models for the coupled oscillations, i.e., Tamura & Shimada model and Parkinson & Corless model are comparatively summarized. Then, the key parameter affecting response amplitude is determined through comparative numerical simulations with Tamura & Shimada model. For rectangular cylinders with the side ratio from 0.5 to 2.5, which are actually prone to develop the VIV and galloping induced interaction responses, an empirical amplitude prediction formula is proposed after regression analysis on comprehensively collected experimental data with the predetermined key parameter.

Efficacy of CFRP configurations for shear of RC beams: experimental and NLFE

  • Shuraim, Ahmed B.
    • Structural Engineering and Mechanics
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    • v.39 no.3
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    • pp.361-382
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    • 2011
  • This paper presents the results of an investigation on shear strengthening of RC beams externally reinforced with CFRP composite. A total of six full-scale beams of four CFRP strengthened and two unstrengthened were tested in the absence of internal stirrups in the shear span. The strengthening configurations contained two styles: discrete uniformly spaced strips and customized wide strips over B-regions. The composite systems provided an increase in ultimate strength as compared to the unstrengthened beams. Among the three layouts that had the same area of CFRP, the highest contribution was provided by the customized layout that targeted the B-regions. A comparative study of the experimental results with published empirical equations was conducted in order to evaluate the assumed effective strains. The empirical equations were found to be unconservative. Nonlinear finite element (NLFE) models were developed for the beams. The models agreed with test results that targeting the B-region was more effective than distributing the same CFRP area in a discrete strip style over shear spans. Moreover, the numerical models predicted the contribution of different configurations better than the empirical equations.