• Title/Summary/Keyword: Empirical factor

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Economic Impact of Information Technology : Empirical Relationship between Informatization level and Productivity (정보기술의 경제적 효과 : 정보화수준과 생산성의 실증적 관계)

  • 조세형;정용균
    • Journal of Information Technology Application
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    • v.3 no.2
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    • pp.25-48
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    • 2001
  • This Study intends to Investigate the economic impact of information technology investment. Six countries in OECD are selected and analyzed to understand the empirical relationship between informatization level and productivity Correlation test and regression analysis are executed, using macro data concerning informatization index, total factor productivity and real output per worker hour The impact of informatization level on productivity is characterized by the time lag effect which is used to explain the productivity paradox in precedent studies. Empirical analysis shows that the higher informatization level and information intensity, the lower time lag effect. The result indicates that IT investment has characteristic as sunk cost and the economic impact is appeared after a certain period of time.

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Performance Characteristic of Large Diameter Oval Finned-Tube Heat Exchanger for Dryer (건조기용 타원관 대구경 핀-관 열교환기의 성능특성)

  • Bae, Kyung-Jin;Cha, Dong-An;Kwon, Oh-Kyung
    • Journal of Power System Engineering
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    • v.18 no.5
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    • pp.22-27
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    • 2014
  • The objectives of this paper are to obtain an empirical equations regarding the correlations between heat transfer and pressure drop of oval fin-tube heat exchanger having large diameter using wilson plot method. It was difficult to find any recommendable heat transfer and friction factor correlation available for our large diameter experimental cases. Overall heat transfer coefficients are composed of the heat transfer coefficients both inside and outside tubes. The resulting empirical correlations for the Nui and f-factor are given as $Nu_i=0.0146Re^{0.809}Pr^{0.3}$ and $f=4.366Re^{-0.64}$, respectively. The empirical correlations of the Nui and f-factors were developed for the large diameter oval finned-tube heat exchanger as a function of the Reynolds number. As the EG(Ethylene glycol) and air flow rate increases, the heat transfer rate and pressure drop is increased largely.

Undrained Shear Strength of Marine Clays of Shihwa Region Obtained from CPTu (CPTu로부터 구한 시화지구 해성점토의 비배수 전단강도)

  • Jang, In-Sung;Kim, Bum-Sang
    • Ocean and Polar Research
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    • v.25 no.spc3
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    • pp.353-360
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    • 2003
  • Estimation of undrained shear strength $(S_u)$ of clayey soils from piezocone penetration test (CPTu), which has widely been known as one of very promising in situ test methods, requires piezocone factors. Empirical correlations are generally utilized to derive piezocone factors, but previous studies on the empirical piezocone factors are site-specific and in some cases need engineering characteristics, which should be obtained from additional laboratory tests. In this study, empirical cone factors were evaluated by comparing 6 CPTu results at Shihwa region in Korea with reference $S_u$ values obtained from field vane test (FVT). From previous CPTu results of other regions in Korea as well as the results herein, the correlations between piezocone factor, $N_{kT}$ and CPTu results were investigated and three simplified evaluation methods of $S_u$ using only CPTu results were presented. The $S_u$ values estimated by $(q_T-{\sigma}_v)/{\sigma}'_v$ method shows better matches with those obtained from laboratory tests for marine clays at Shihwa region.

A Study on the Empirical Evaluation of Quality Factor on Library Service for the Disabled (도서관장애인서비스 품질요인의 실증적 평가에 대한 연구)

  • Bae, Kyung-Jae
    • Journal of the Korean Society for Library and Information Science
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    • v.50 no.2
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    • pp.271-287
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    • 2016
  • This study intends to review the quality factors of library service for the disabled using user-centered approach. For the empirical review of quality factors, Nine quality factors were drawn after analyzing the current library service quality factors and the standards of library service for the disabled. Using these factors, The survey for identifying importance of factors and the qualitative evaluation of service cases were performed in this study. As a result of this survey, the most critical but relatively weak quality factors were facility, collection and staff factors. And the qualitative evaluation results of service cases indicated that the reading culture program and the information service factors were critical.

A Exploratory Study on the Factor Affecting the Depression of Immigrant Labor: The Case of Myanmar Male Immigrant Labor (이주노동자의 우울감에 영향을 미치는 요인에 관한 탐색적 연구: 제조업 미얀마남성이주노동자의 경우)

  • Yun, Yeong-Sam;Lee, Jeong-Sik;Khine, Wei-Wei
    • Asia-Pacific Journal of Business
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    • v.12 no.4
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    • pp.135-151
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    • 2021
  • Purpose - This paper analyzes the effect of factors affecting the depression of immigrant labor by the exploratory multivariate model empirically. Design/Methodology/Approach - We review results of precedent studies theoretically and implement empirical study by using the questionnaire data of Myanmar male immigrant labor. Findings - As the result of empirical study, the factor affecting the depression of immigrant labor significantly at p<0.5 level are 'interpersonal trouble in company', 'unjust wage' and 'bottleneck to life'. Also 'unjust treatment' and 'anxiety(of health)' are affecting factors significantly at p<0.1. Research Implications - Managerial implications are as follow. Firstly, employers have to reduce 'interpersonal trouble in company', 'unjust wage' and 'unjust treatment'. Secondly, gonernment have to support to reduce 'bottleneck to life' and 'anxiety(of health)'. Academic implications are as follow. Firstly, factors that are studied exploratively have to be tested by systematic empirical study. Secondly, which of short-term, lagged or cumulative is the nature of the affecting effect and the reciprocal relationship between depression and factors affecting the depression has to be studied empirically.

The Characteristic of Friction-Factor on Honeycomb Surfaces (Part II : Friction-Factor Jump Phenomenon) (허니콤 표면의 마찰계수 특성에 관한 연구 (Part 2 : 마찰계수 급상승현상에 관한 고찰))

  • 하태웅
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.6
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    • pp.1439-1447
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    • 1994
  • Test results of friction-factor for the flow of air in a narrow channel lined with various honeycomb geometries show that, generally, the friction-factor is nearly constant or slightly decreases as the Reynolds number(or Mach number) increases, a characteristic common to turbulent flow in pipes. However, in some test geometries this trend is remarkably different. The friction factor dramatically drops and then rises as the Mach number increases. This phenomenon can be characterized as a "friction-factor jump." Further investigations of the acoustic spectrum indicate that the "friction-factor jump" phenomenon is accompanied by an onset of a normal mode resonance excited coherent flow fluctuation structure, which occurs at Reynolds number of the order of $10^4$. New empirical friction-factor model for "friction-factor jump" cases is developed as a function of Mach number and local pressure.ach number and local pressure.

An Empirical Analysis on Public Transportation Demand and TOD Design Factors in Seoul subway adjacent area (서울시 역세권의 TOD환경과 대중교통이용수요 관계분석)

  • Moon, Young-Il;Rho, Jeong-Hyun
    • International Journal of Highway Engineering
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    • v.13 no.4
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    • pp.211-220
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    • 2011
  • TOD(Transit Oriented Development) has recently been active, which presents that TOD planning elements should be comprehensively taken into consideration in order to enhance domestic transit ridership by changing environments in rail station areas and an empirical analysis on the type of rail station areas and transportation demand should be a prerequisite for usage of future development planning. This study aims to grasp a variety of TOD of influence factors in Seoul rail station area and to perform analysis to identify relationship between public transportation demand and these TOD design factors. To make it come true, we gathered data with respect to Density, Diversity, and Accessibility as representative TOD planning elements and carried out factorial and regression analysis. Consequently, we drew 7 influence factors base on factorial analysis: Factor 1(Diversity/ -Use Mix(LUM)), Factor 2(Density/development density), Factor 3(Accessibility/public transportation facility supply), Factor 4(Design/street design), Factor 5(Green/access mode (pedestrian, bike), Factor 6(Design/subway size), Factor 7(Accessibility/Public transit operation) As the result of model development by using factorial and regression analysis, positive influence factors on passenger flow in rail station area are Factor 1(Diversity : Land-Use Mix), Factor 3(Accessibility : public transportation facility supply), Factor 2(Density : development density), Factor 5(Design/ access mode) and Factor 6(subway size) Next, negative influence factor on passenger flow in rail station area shows Factor 7(Accessibility/Public transit operation) as the most influential factor. This is because the growth of service interval of linked subway and bus leads to reduced demand.

An Empirical Study on the Determinants of Repurchase Intention in Mobile Internet Services (무선인터넷서비스 이용 결정 요인에 관한 연구 - 재구매 의도에 영향을 미치는 요인을 중심으로)

  • 최선미;박명철
    • Journal of Korea Technology Innovation Society
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    • v.6 no.1
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    • pp.92-109
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    • 2003
  • To launch effective mobile Internet marketing strategies, firms need to understand mobile Internet user behavior. Thus in this study we investigated factors that affect on the repurchase intention of mobile Internet users. A random sample of 501 users was surveyed. Overall satisfaction (mediating factor), flow and interactivity factors (initial factor) were found to have the most significant impact on the reuse intention and discrepancy factor is not significant to the reuse intention.

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The Effect of Surface-Friction-Factor-Jump Characteristics on Retordynamics of a Seal (마찰계수 급상승 특성이 실의 로터다이나믹 특성에 미치는 영향)

  • 하태웅
    • Journal of KSNVE
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    • v.6 no.2
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    • pp.197-203
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    • 1996
  • This study is to analyze the rotordynamic effect of surface-friction- factor characteristics on an annular seal. The honeycomb geometry which shows friction-factor-jump phenomena is used in this study. A rotordynamic analysis for a contered annular seal has been developed by incorporating empirical friction-factor model for honeycomb stator surfaces. The results of the analysis for the honeycomb seal showing the friction-factor jump is compared to the non- friction-factor-jump case. The results yield that the friction-factor-jump decreasesdirect stiffness and cross coupled stiffness coefficients, and increases damping coefficient to stabilize rotating machinery in a rotordynamic point of view. The analysis of the honeyeomb seal for the friction-factor-jump case shows reasonably good compared to experimental results, especially, for cross coupled and damping coeffcients.

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Developing the Vulnerability Factor Structure Affecting Injuries and Health Problems Among Migrant Seafood Processing Industry Workers

  • Jiaranai, Itchaya;Sansakorn, Preeda;Mahaboon, Junjira
    • Safety and Health at Work
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    • v.13 no.2
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    • pp.170-179
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    • 2022
  • Background: The vulnerability of international migrant workers is on the rise, affecting the frequency of occupational accidents at workplaces worldwide. If migrant workers are managed in the same way as native workers, the consequences on safety assurance and risk management will be significant. This study aimed to develop the vulnerability factor model for migrant workers in seafood processing industries because of significant risk-laden labor of Thailand, which could be a solution to control the risk effectively. Methods: A total of 569 migrant workers were surveyed (432 Burmese and 137 Cambodian), beginning with 40 initial vulnerability factors identified in the questionnaire established from experts. The data were analyzed through descriptive analysis; exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to ascertain the model. Results: The result of content validity >0.67 and the Cronbach's alpha of 0.957 specified the high reliability of 40 factors. The EFA indicated a total variance of 65.49%. The final CFA validated the model and had an empirical fitting; chi-square = 85.34, Adjust Goodness-of-Fit Index = 0.96, and root mean square error of approximation = 0.016. The structure concluded with three dimensions and 18 factors. Dimension 1 of the structure, "multicultural safety operation," contained 12 factors; Dimension 2, "wellbeing," contained four factors; and Dimension 3, "communication technology," contained two factors. Conclusion: The vulnerability factor structure developed in this study included three dimensions and 18 factors that were significantly empirical. The knowledge enhanced safety management in the context of vulnerability factor structure for migrant workers at the workplace.