• Title/Summary/Keyword: Validity Analyses

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Application of Proposed Rating Equations using LRFD Beam-Column Interaction Equations for Girders and Towers in Steel Cable-Stayed Bridges (강사장교 거더와 주탑에 하중저항계수설계법의 보-기둥 상관식을 사용한 내하율 산정식 적용)

  • Choi, Dong Ho;Yoo, Hoon;Lee, Beom Soo;Cho, Sun Kyu
    • Journal of Korean Society of Steel Construction
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    • v.19 no.1
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    • pp.1-13
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    • 2007
  • As girders and towers in cable-stayed bridges are subject to bending moments as well as axial forces, the conventional load rating equation, which considers only the single force effect, cannot be used to evaluate the rating factors of cable-stayed bridges. The load rating equation for components in cable-stayed bridges is not currently established yet. In this paper, we propose load rating equations for girders and towers in cable-stayed bridges using the interaction equations for beam-column members. Moving load analyses were performed for the cases of a maximum axial compressive force, maximum positive moment and maximum negative moment for each component in cable-stayed bridges and detailed procedures to apply proposed equations were presented. The Dolsan Grand Bridge was used to verify the validity of proposed equations. The conventional load rating equation overestimates rating factors of girders and towers in the Dolsan Grand Bridge, whereas proposed equations properly reflect the axial-flexural interaction behaviour of girders and towers in cable-stayed bridges.

Analysis of the Factors Affecting MIS Success : Focusing on the Small Business of Manufacturing Industry in Korea (경영정보시스템의 성공과 실패에 대한 요인 분석 : 우리나라 제조업 분야의 중소기업을 중심으로)

  • Kang, Byeong-Gu
    • Asia pacific journal of information systems
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    • v.5 no.1
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    • pp.236-257
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    • 1995
  • Not much attention has been paid to the characteristics of successful MIS in small business in Korea. This study compares the characteristics of successful MIS with those of less successful MIS of manufacturing industry in Korea in terms of micro level, macro level, and personal level. The micro level consists of those variables relating to the system development and maintenance while the macro level consists of the environmental variables relating to the information systems. The personal level measures a personal EDP experience. A mail survey was sent to small manufacturing companies to collect the data for the hypothesis tests. And 81 usable questionnaires were returned for data analysis. This study performs the validity of the categorization of variables in terms of three levels. The results shows that this categorization is appropriate but the personal level. As the personal experiences of EDP in Korea used to come up with those of the organization, the variables in the personal level have high correlations with those in the macro level in empirical testing. As the personal level, however, is different dimension from the macro level in theoretical aspect, the level is maintained separately throughout the study. The data were analyzed with MANOVA and two group discriminant analysis. The analyses reveal that the characteristics of successful MIS are different from those of less successful MIS in terms of three levels. And the micro level is more important than the macro level to develop successful MIS. That is because the organizations have relatively few experience in dealing with information systems, they have not developed unique information systems which are adjusted to their organizational characteristics. Those findings seems to be important determinants of success for the MIS in a firm.

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The Effect of Appearance Management Behavior on Job Search Efficacy among Female College Students (여대생의 외모관리행동이 구직효능감에 미치는 영향)

  • Kim, Mikyung;Kim, Sung Hee
    • Journal of Fashion Business
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    • v.21 no.5
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    • pp.78-90
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    • 2017
  • This study investigates the effects of appearance management behaviors on job search efficacy among female college students. Based on previous studies on appearance management behaviors and job search efficacy, the questionnaire items were developed. For the study, we conducted a questionnaire survey among 312 students from women's university in Seoul. The statistical analyses were performed using SPSS 23. The results were as follows. First, three types of appearance management factors have been identified: 'fashion & hair,' 'skin care & plastic surgery,' and 'body shape'; the reliability and validity of these factors were proved. Second, the appearance management behavior of female college students found to have a partially significant effect on job search efficacy: fashion & hair factor had a positive effect on job search strength; fashion & hair factor and body shape factor had a positive effect on job search skills. While skin care & plastic surgery factor had a negative effect on job search strength and job search skill. Third, between academic years, there were differences in job search efficacy but not in appearance management behavior. By majors, there were differences among skin care & plastic surgery factor, body shape factor, and job search strength factor. These results suggest that to improve the job search efficacy, proper appearance management through fashion and hair, and body shape management is necessary. In addition, it suggests that it is important to improve the effectiveness of employment by establishing the appearance management strategy that matches the characteristics of each major.

The Effects of Fashion Behaviors and Impression Management Behaviors on Career Success of Male Office Workers -Applying PLS Structural Equation Modeling- (직장남성의 패션행동 및 인상관리행동이 경력성공에 미치는 영향 -PLS 구조방정식 모형을 적용하여-)

  • Ryu, Eun Suk;Ryu, Eun Young
    • Journal of the Korean Society of Clothing and Textiles
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    • v.40 no.1
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    • pp.131-147
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    • 2016
  • This study investigated the relationship between fashion behavior, impression management behavior, and career success. A conceptual model and hypotheses were established based on theoretical linkages between the constructs. Thereafter, empirical data were collected using a set of questionnaires. For this reason, the sample was taken from 720 office workers' who worked at 14's Korea Enterprise, 697 of which was used for an empirical analysis (sample: men over 30 years of age and more than three years continuous service). This study conducted an exploratory factor analysis and confirmatory factor analysis for the validity test. Cronbach's alpha test is used for the reliability test. Moreover, PLS structural equation modeling (SEM) was employed to test hypothesized relationships in the conceptual model (SPSS 20.0 window/Smart PLS 3.0). This study shows that the proposed model is reasonably fit to the actual data. The following results were obtained from the analyses. First, fashion behavior and impression management behavior is positively related to career success. The result shows that economics of the fashion behaviors sub-types were statistically more significant to influence career success. The self-focused of the impression management behavior sub-types were more than statistically significant to influence career success. This finding has great implications to understand self-management behavior and the career success of male office workers.

Multidisciplinary UAV Design Optimization Implementing Multi-Fidelity Analysis Techniques (다정밀도 해석기법을 이용한 무인항공기 다분야통합 최적설계)

  • Lee, Jae-Woo;Choi, Seok-Min;Van, Nguyen Nhu;Kim, Ji-Min;Byun, Yung-Hwan
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.8
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    • pp.695-702
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    • 2012
  • In this study, Multi-fidelity analysis is performed to improve the accuracy of analysis result during conceptual design stage. Multidisciplinary Design Optimization(MDO) method is also considered to satisfy the total system requirements. Low-fidelity analysis codes which are based on empirical equations are developed and validated for analyzing the Unmanned Aerial Vehicle(UAV) which have unconventional configurations. Analysis codes consist of initial sizing, aerodynamics, propulsion, mission, weight, performance, and stability modules. Design synthesis program which is composed of those modules is developed. To improve the accuracy of the design method for UAV, Vortex Lattice Method is used for the strategy of MFA. Multi-Disciplinary Feasible(MDF) method is used for MDO technique. To demonstrate the validity of presented method, the optimization results of both methods are compared. According to those results, the presented method is demonstrated to be applicable to improve the accuracy of the analyses during conceptual design stage.

Analytical Study for Performance Improvement of Studs for Steel Plate Concrete(SC) Walls subjected to Bending Moment (휨모멘트를 받는 강판 콘크리트(SC) 벽체에서 스터드의 성능개선을 위한 해석적 연구)

  • Cho, Sung-Gook;Lim, Jin-Sun;Jeong, Young-Do;Yi, Seong-Tae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.2
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    • pp.74-81
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    • 2014
  • In this study, it was conducted to improve the performance of stud of Steel Plate Concrete(SC) walls subjected to bending moment. Non-linearity of contact interface, connection, and material properties were considered in finite element modeling of SC wall. In order to validate the analytical model, furthermore, a foregoing laboratory experiment was simulated by FEM, so that comparison between the measured result and the analysis result have be done. The size of the analytical model was determined by reflecting various references and the analyses were performed according to various shapes and arrangements of stud. Additionally, the validity of the model considering the related provisions in the KEPIC SNG standard was also considered. As a result, the optimal shape and spacing of studs was proposed through this numerical analysis and standard verification.

Validation of the emission inventory of volatile organic compounds in Seoul (서울의 휘발성유기화합물 배출량 자료 검증)

  • Kim, Yong Pyo
    • Particle and aerosol research
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    • v.5 no.3
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    • pp.139-148
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    • 2009
  • In Seoul, the largest emission source for volatile organic compounds (VOCs) based on the emission inventory is solvent usage followed by vehicular exhaust. However, according to a CMB modeling result by Na and Kim (2007), vehicular exhaust was the largest emission source followed by solvent usage. Detailed analyses on the validity of the CMB model result were carried out and it was suggested that the existing emission inventory for VOCs might be underestimating vehicular emission. Scientific considerations that should be considered for the effective control strategy against VOCs are discussed.

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Development of Social Work Values Scale (사회복지 가치 척도의 개발)

  • Kim, Yongseok;Ko, Eunjung
    • Korean Journal of Social Welfare
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    • v.66 no.1
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    • pp.277-306
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    • 2014
  • The purpose of this study was to develop the first social work values scale in Korea. Its development would be expected to increase empirical studies on social work values. Based upon the literature review of social work values, the examination of codes of ethics as well as existing scales, and the comments from professionals in this field, 62 preliminary items were developed. Preliminary items were evaluated with a total of 521 social workers who were working in various fields of social work in Seoul and surrounding areas. A series of exploratory factor analyses were conducted to find out the optimal structure of the scale. After deleting 29 items with low factor loadings or being cross-loaded, the scale is composed of three factors with each factor having 11 items. Confirmatory factor analysis confirmed the factor structure of the scale obtained by exploratory factor analysis. The first factor was named autonomy, the second factor was named equality, and third factor was named paternalistic intervention. Each component of the social work values scale is found to be reliable and valid.

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The Prediction and Analysis of the Power Energy Time Series by Using the Elman Recurrent Neural Network (엘만 순환 신경망을 사용한 전력 에너지 시계열의 예측 및 분석)

  • Lee, Chang-Yong;Kim, Jinho
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.1
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    • pp.84-93
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    • 2018
  • In this paper, we propose an Elman recurrent neural network to predict and analyze a time series of power energy consumption. To this end, we consider the volatility of the time series and apply the sample variance and the detrended fluctuation analyses to the volatilities. We demonstrate that there exists a correlation in the time series of the volatilities, which suggests that the power consumption time series contain a non-negligible amount of the non-linear correlation. Based on this finding, we adopt the Elman recurrent neural network as the model for the prediction of the power consumption. As the simplest form of the recurrent network, the Elman network is designed to learn sequential or time-varying pattern and could predict learned series of values. The Elman network has a layer of "context units" in addition to a standard feedforward network. By adjusting two parameters in the model and performing the cross validation, we demonstrated that the proposed model predicts the power consumption with the relative errors and the average errors in the range of 2%~5% and 3kWh~8kWh, respectively. To further confirm the experimental results, we performed two types of the cross validations designed for the time series data. We also support the validity of the model by analyzing the multi-step forecasting. We found that the prediction errors tend to be saturated although they increase as the prediction time step increases. The results of this study can be used to the energy management system in terms of the effective control of the cross usage of the electric and the gas energies.

The Development of Self-regulation Program Elementary School Students' to Improve Willpower (초등학생의 의지력 향상을 위한 자기조절 프로그램 개발)

  • An, Kwan-Su;Hwang, Jae-yeon
    • Journal of Digital Convergence
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    • v.15 no.1
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    • pp.413-425
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    • 2017
  • The objective of this study is to develop the self-regulation program for senior class students of elementary school to improve willpower. The data on basic need for the self- regulation program was collected using a five-point Likert scale and the participants were 93 students from the fifth-grade and sixth-grade of elementary school. And 32 elementary school teachers participated in this study. The need-survey was conducted for the contents analyses and process elements of this program. Eight experts accomplished program structure and contents design performed by 2 tests on validity. This program consisted of making the student complete one target-behavior that caused him into developing willpower. Self-monitoring and rewarding are the strategy to develop willpower and the students who executed this program developed good attitudes.