• Title/Summary/Keyword: Goodness-of-Fitness

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Practical Study on Adjustment of Load Correlation Equations of Pole Transformer (주상변압기 부하 상관식 조정에 관한 실증적 연구)

  • 박창호;김두봉;김기현;배주천;윤상윤;김재철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.1
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    • pp.102-108
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    • 2000
  • This paper presents a result of practical study about the adjustment of load correlation equation for the load management of pole transformer. For adjusting the load correlation equation, we analyze the correlative relation between working electric energy[kWh] and peak load[A]. To enhance the accuracy of correlation equation, we classify the 12 representative area patterns. And then, we select the 24 sample pole transformer for each area pattern. For the reliability of the data using the load correlation equation, load management equipment is utilized for each sample pole transformer. Through the on-line data acquisition, we construct the database. For adjusting the load correlation equation, we consider the two points. One is the goodness of fitness for load correlation equation and the other is prevention of pole transformer damage due to the overload. Finally, we propose the correlation equation using the linear and quadratic equation all at once. Through the case studies, we verify that the proposed load correlation equation is reduced the error ratio than conventional correlation equation.

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The estimation of CO concentration in Daegu-Gyeongbuk area using GEV distribution (GEV 분포를 이용한 대구·경북 지역 일산화탄소 농도 추정)

  • Ryu, Soorack;Eom, Eunjin;Kwon, Taeyong;Yoon, Sanghoo
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.4
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    • pp.1001-1012
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    • 2016
  • It is well known that air pollutants exert a bad influence on human health. According to the United Nations Environment Program, 4.3 million people die from carbon monoxide and particulate matter annually from all over the world. Carbon monoxide is a toxic gas that is the most dangerous of the gas consisting of carbon and oxygen. In this paper, we used 1 hour, 6 hours, 12 hours, and 24 hours average carbon monoxide concentration data collected between 2004 and 2013 in Daegu Gyeongbuk area. Parameters of the generalized extreme value distribution were estimated by maximum likelihood estimation and L-moments estimation. An evalution of goodness of fitness also was performed. Since the number of samples were small, L-moment estimation turned out to be suitable for parameter estimation. We also calculated 5 year, 10 year, 20 year, and 40 year return level.

A Study on the Factors affecting Cyber-Career-Counseling-Activation based on Structural Equation Model(SEM) (구조방정식 모형을 이용한 사이버진로상담 활성화 영향요인에 관한 연구)

  • Lee, Young-Ja;Baek, Hyeon-Gi
    • Journal of Digital Contents Society
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    • v.9 no.3
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    • pp.379-388
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    • 2008
  • This paper is to redefine the concept of Cyber Career Counseling Activation(=C-C-C-A) and verify the effects of the factors affecting the C-C-C-A at Korean academic high school level in Kyunggi Province. In this research, we hypothesize that the three independent variables increase the effects of Cyber Career Counseling Activation.. To discuss the hypothesis, we analyzed survey data of 322 students who had taken Cyber Career Counseling in December 2007 based on Structural Equation Model. The results are as follows: First, the three crucial factors(Expanding C-C-C Opportunities, Improving C-C-C Service, Establishing C-C-C Service System) increase the C-C-C-A effectiveness. Second, as a result of Confirmatory Factor Analysis(CFA), the goodness of fit indices(GFI, AGFI, CFI, RMSEA) demonstrate statistical significance and fitness of the C-C-C-A Model. Therefore, the outcomes show that the three factors are the significant ones of Cyber Career Counseling Activation Model.

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Integrated Procedure of Self-Organizing Map Neural Network and Case-Based Reasoning for Multivariate Process Control (자기조직화 지도 신경망과 사례기반추론을 이용한 다변량 공정관리)

  • 강부식
    • Journal of Intelligence and Information Systems
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    • v.9 no.1
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    • pp.53-69
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    • 2003
  • Many process variables in modem manufacturing processes have influence on quality of products with complicated relationships. Therefore, it is necessary to control multiple quality variables in order to monitor abnormal signals in the processes. This study proposes an integrated procedure of self-organizing map (SOM) neural network and case-based reasoning (CBR) for multivariate process control. SOM generates patterns of quality variables. The patterns are compared with the reference patterns in order to decide whether their states are normal or abnormal using the goodness-of-fitness test. For validation, it generates artificial datasets consisting of six patterns, normal and abnormal patterns. Experimental results show that the abnormal patterns can be detected effectively. This study also shows that the CBR procedure enables to keep Type 2 error at very low level and reduce Type 1 error gradually, and then the proposed method can be a solution fur multivariate process control.

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A Study on an ETCS Demand Forecasting Model of Toll Roads in Changwon City (유료도로 ETCS 이용수요 예측모형에 관한 연구 (창원시를 중심으로))

  • Kim, Kyung-Whan;Ha, Man-Bok;Jeon, Yeon-Hoo;Lee, Ik-Su
    • International Journal of Highway Engineering
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    • v.9 no.1 s.31
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    • pp.17-27
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    • 2007
  • Since early 1990s, several developed countries have applied the Electronic Toll Collection System (ETCS) to toll roads in order to solve traffic congestion and delay problems at toll plazas. For the successful operation of the ETCS, it is important to correctly forecast the ETCS using rate. In this study, it was conceived to develop a sophisticated demand forecasting model of the ETCS for toll roads in Changwon City The Binary Logit and neural network models were tested for the model considering 11 explaining variables. The best results in prediction accuracy and goodness-of-fit were obtained on the neural network model. However, because of the difficulty in predicting the 11 variables and its fitness in wide range, the Binary Logit model which considers three policy variables only is recommended as the model to forecast the ETCS using rate.

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Rietveld Structure Refinement of Biotite Using Neutron Powder Diffraction (중성자분말회절법을 이용한 흑운모의 Rietveld Structure Refinement)

  • 전철민;김신애;문희수
    • Economic and Environmental Geology
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    • v.34 no.1
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    • pp.1-12
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    • 2001
  • The crystal structure of biotite-1M from Bancroft, Ontario, was determined by Rietveld refinement method using high-resolution neutron powder diffraction data at -26.3$^{\circ}C$, 2$0^{\circ}C$, 30$0^{\circ}C$, $600^{\circ}C$, 90$0^{\circ}C$. The crystal structure has been refined to a R sub(B) of 5.06%-11.9% and S (Goodness of fitness) of 2.97-3.94. The expansion rate of a, b, c unit cell dimensions with elevated temperature linearly increase to $600^{\circ}C$. The expansivity of the c dimension is $1.61{\times}10^{40}C^{-1}$, while $2.73{\times}10^{50}C^{-1}$ and $5.71{\times}10^{-50}C^{-1}$ for the a and b dimensions, respectively. Thus, the volume increase of the unit cell is dominated by expansion of the c axis as increasing temperature. In contrast to the trend, the expansivity of the dimensions is decreased at 90$0^{\circ}C$. It may be attributed to a change in cation size caused by dehydroxylation-oxidation of $Fe^{2+}$ to $Fe^{3+}$ in vacuum condition at such high temperature. The position of H-proton was determined by the refinement of diffraction pattern at low temperature (-2.63$^{\circ}C$). The position is 0.9103${\AA}$ from the O sub(4) location and located at atomic coordinates (x/a=0.138, y/b=0.5, z/c=0.305) with the OH vector almost normal to plane (001). According to the increase of the temperature, $\alpha$* (tetrahedral rotation angle), $t_{oct}$ (octahedral sheet thickness), mean distance increase except 90$0^{\circ}C$ data. But the trend is less clearly relative to unit cell dimension expansion because the expansion is dominant to the interlayer. Also, ${\Psi}$ (octahedral flattening angle) shows no trends as increasing temperature and it may be because the octahedron (M1, M2) is substituted by Mg and Fe.

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Derivation of Plotting Position Formulas Considering the Coefficients of Skewness for the GEV Distribution (왜곡도 계수를 고려한 GEV 분포의 도시위치공식 유도)

  • Kim, Soo-Young;Heo, Jun-Haeng;Choi, Min-Young
    • Journal of Korea Water Resources Association
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    • v.44 no.2
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    • pp.85-96
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    • 2011
  • Probability plotting position is generally used for the graphical analysis of the annual maximum quantile and the estimation of exceedance probability to display the fitness between sample and an appropriate probability distribution. In addition, it is used to apply a specific goodness of fit test. Plotting position formula to define the probability plotting position has been studied in many researches. Especially, the GEV distribution which is an important probability distribution to analyze the frequency of hydrologic data was popular. In this study, the theoretical reduced variates are derived using the mean value of order statistics to derived an appropriate plotting position formula for the GEV distribution. In addition, various forms of plotting position formula considering various sample sizes and coefficients of skewness related with shape parameters are applied. The parameters of plotting position formulas are estimated using the genetic algorithm. The accuracy of derived plotting position formula is estimated by the errors between the theoretical reduced variates and those by various plotting position formulas including the derived ones in this study. As a result, the errors by derived plotting position formula is the smallest at the range of shape parameter with -0.25~0.10.

Rietveld Refinement and Crystal Structure of K-Ba Substituted Synthetic Hollandite, ($K_{2x}Ba_{1-x}Cr_2Ti_6O_{16}$) (리트벨트법을 이용한 K-Ba 치환 합성 홀란다이트($K_{2x}Ba_{1-x}Cr_2Ti_6O_{16}$)의 결정구조 연구)

  • 최진범;김태현
    • Journal of the Mineralogical Society of Korea
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    • v.14 no.2
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    • pp.128-136
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    • 2001
  • The K-Ba complete solid solution of 7 synthetic hollandite-type minerals ($K_{2x}$ $Ba_{1-x}$ $Cr_2$/$Ti_{6}$ $O_{16}$ , x=0, 0.1, 0.3, 0.5, 0.7, 0.9, 1.0, respectively) are studied by the X-ray powder diffraction and Rietveld refinement to find structural transformation during substitution of $Ba^{2+}$ by $K^{+}$ in A site of the tunnel structure of hollandite. Rietveld indices indicate that $R_{wp}$ with respect to $R^{exp}$ ($R_{wp}$ $R_{exp}$ ) are in the range of 15.66%/20.90% and 14.74%/l9.37%, $R_{B}$ and S(Goodness of Fitness) are 6.45~8.97%, 1.45~1.63, respectively. Unit cell parameters of synthetic hollandites, space group 14/m, are a=10.1194(2)~10.0599(2)$\AA$, c=2.9572(6)~2.9512(7)$\AA$, and V=302.75~298.66$\AA^{3}$. Rutile formed as an impurity in those with more than 50% K contents in hollandite series. Substitution of Ba by K ion in a tunnel structure results in constant decrease of cell parameters, but is not sufficient enough to change the hollandite structure. Our data indicate that transformation of tetragonal 14/m to lower symmetry of monoclinic 12/m in hollandite structure may at least be affected by other cation substitution in same A site and/or by cation substitution in B site.

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Effect of Oral Health Education Practice and Self-efficacy of Teacher on Oral Health Attitude (교사의 구강보건교육 실천과 자기효능감이 구강보건교육 태도에 미치는 영향)

  • Cho, Young-Sik;Hwang, Yoo-Jin;Bae, Hyun-Sook;Kim, Seo yune
    • Journal of dental hygiene science
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    • v.9 no.1
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    • pp.99-108
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    • 2009
  • The purpose of this study was to investigate the effect of oral health education practice and schoolteacher's self-efficacy on oral health attitude. The data of 217 dental hygienists was subjected to path analysis using AMOS 16.0. Oral health knowledge, attitude, self-efficacy and oral health education practice of schoolteacher were measurement variables of three path models. The goodness of fitness of Knowledge-Attitude-Practice model and Knowledge-Attitude-Self efficacy -Practice model were acceptable. The regression weights of two models were statistically significant. Oral health education practice of schoolteacher gave impact on oral health attitude by mediation of self-efficacy of schoolteacher. Self-efficacy of schoolteacher was a important determinant of oral health education practice. Oral health attitude and practice were supposed to be mutual determinants of health behavior models.

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A Structural Relationship among Job Requirements, Job Resources and Job Burnout, and Organizational Effectiveness of Private Security Guards (민간경비원의 직무요구 직무자원과 소진, 조직유효성의 구조적 관계)

  • Kim, Sung-Cheol;Kim, Young-Hyun
    • Korean Security Journal
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    • no.48
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    • pp.9-33
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    • 2016
  • The purpose of the present study was to find out cause-and-effect relationship between job requirements and job resources, with job burnout as a mediator variable, and the effects of these variables on organizational effectiveness. The population in the present study was private security guards employed by 13 private security companies in Seoul and Gyeonggi-do areas, and a survey was conducted on 500 security guards selected using purposive sampling technique. Out of 460 questionnaires distributed, 429 responses, excluding 31 outliers or insincere responses, were used for data analysis. For analysis, data were coded and entered into SPSS 18.0 and AMOS 18.0, which were used to analyze the data. Descriptive analyses were performed to find out sociodemographic characteristics of the respondents. The exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to test the validity of the measurement tool, and the Cronbach's Alpha coefficients were calculated to test the reliability. To find out the significance of relationships among variables, Pearson's correlation analysis was performed. Covariance Structure Analysis (CSA) was performed to test the relationship among latent factors of a model for job requirements, job resources, job burnout, and organizational effectiveness of the private security guards, and the fitness of the model analyzed with CSA was determined by the goodness-of-fit index ($x^2$, df, p, RMR, GFI, CFI, TLI, RMSEA). The level of significance was set at .05, and the following results were obtained. First, even though the effect of job requirements on job burnout was not statistically significant, it had a positive influence overall, and this result can be considered such that the higher the perception of job requirements by the member of the organization, the higher the perception of job burnout. Second, the influence of job resources on job burnout was negative, which can be considered that the higher the perception of job resources, the lower the perception of job burnout. Third, even though the influence of job requirements on organizational effectiveness was statistically nonsignificant, it had a negative influence overall, and this result can be considered that the higher the perception of job requirements, the lower the perception of organizational effectiveness. Fourth, job resources had a positive influence on organizational effectiveness, and it can be considered that the higher the perception of job resources, the higher the perception of organizational effectiveness. Fifth, the results of the analysis between job burnout and organizational effectiveness revealed that, even though the influence of job burnout on organizational effectiveness was statistically nonsignificant, it had partial negative influences on sublevels of organizational effectiveness, and this may suggest that the higher the perception of job burnout by the organization members, the lower the organizational effectiveness. Sixth, the analysis of mediating role in the relationship between job requirements and organizational effectiveness, job burnout was taking partial mediating role between job requirements and organizational effectiveness. These results suggest that reducing job burnout by managing job requirements, organizational effectiveness that leads to job satisfaction, organizational commitment, and turnover intention can be maximized. Seventh, the analysis of mediating role in the relationship among job requirements, job resources, and organizational effectiveness, job burnout was assuming a partial mediating role in the relationships among job requirements, job resources, and organizational effectiveness. These results suggest that organizational effectiveness can be maximized by either lowering job requirements or burnout management through reorganizing job resources.

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