• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.63-66
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• 2007

Reformers which produce hydrogen from natural gas are essential for the operation of residential PEM fuel cells. For this purpose, steam-methane reforming reactions with Ni catalysts is primarily utilized. Commercial Ni catalysts are generally made to have porous pellet shapes in which Ni catalyst particles are uniformly dispersed over Alumina support structures. This study numerically investigates the reduction of catalyst effectiveness due to the mass transport resistances posed by porous structures of spherical catalyst pellets. The multi-component diffusion through porous media and the accurate kinetics of reforming reaction is fully considered in the numerical model. The preliminary results on the variation of the effectiveness factor according to different operation conditions are presented, which is planned to be used to develop correlations in future studies.

• Journal of the Korean Society for Library and Information Science
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• v.35 no.1
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• pp.5-25
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• 2001

The second research of "a study of the evaluation indicators in Korean public libraries" had as its major objective the identification of indicators and broad dimensions of public library effectiveness in Korea. The managers and librarians of the 175 public libraries in the sample were asked to rate the performance of their libraries. Factor analysis was used to derive 11 dimensions of effectiveness. The dimensions fit four different models of organizational effectiveness.ctiveness.

• Journal of the Korea Society of Computer and Information
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• v.24 no.6
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• pp.29-35
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• 2019

In this paper, the effects of educational contents on job behavior, the effects of job behavior on job effectiveness and the effects of educational contents on job effectiveness were studied when working in the Software field. For this purpose, a questionnaire survey was conducted on the learning workers who conducted the training in the IT field, and 302 valid questionnaires were used for the analysis. The research model was set up to test exploratory factor and confirmatory factor analysis and hypothesis, and the research hypothesis was tested by applying structural equation. The effects of job behavior on job effectiveness were positively related to job satisfaction, customer orientation, and organizational commitment.

• Women's Health Nursing
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• v.22 no.4
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• pp.264-274
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• 2016

Purpose: The purpose of this study was to develop and evaluate breastfeeding effectiveness scale to measure effectiveness of breastfeeding for mothers in the early postpartum period. Methods: A conceptual framework was constructed from properties of effective breastfeeding (Yang and Seo, 2011), and item construction was derived from literature review and analysis of the data along with interviews with breastfeeding mothers. Content validity was tested by experts. Each item was scored on a five-point Likert scale. The preliminary questionnaire was administered to 248 breastfeeding mothers. Data were analyzed using item analysis, factor analysis, Pearson correlation coefficients, and Cronbach's ${\alpha}$. Results: From the factor analysis, 20 items in seven factors were derived. The factors were identified as mother's satisfaction, suckling, assurance of milk quantity, infant's satisfaction, latching on, infant's feeding desire, and breastfeeding positioning. The seven factors explained 65.1% of total variance, Cronbach's ${\alpha}$ of the total items was .83 and the factors ranged from .44 to .75. Conclusion: Results of this study suggest that breastfeeding effectiveness scale is a reliable and valid instrument to measure breastfeeding effectiveness of mothers in the early postpartum period.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.343-350
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• 2019

Objectives: This study aims to identify whether ventilation conditions and their effectiveness can be significantly improved in an experimental chamber by increasing the mixing factor (K-Factor). Methods: In a chamber with a volume of $1m^3$, air velocity was measured at six different points with four roof fans in the upper part of the chamber being operated in order. The impact of the ventilation conditions was analyzed when the flow rates were increasing and the first inlet of the chamber was either open or closed. Smoke patterns were also observed at four corner points where ventilation was limited. Kruskal Wallis and Mann-Whitney tests were performed to compare air velocities measured in the chamber. Results: The air velocities measured at only the third point increased significantly from $0.03{\pm}0.03m/s$ (door open) and $0.05{\pm}0.06m/s$ (door closed) with two fans, $0.08{\pm}0.08m/s$ with three fans, and $0.09{\pm}0.09m/s$ with four fans operating (p<0.05). However, air velocities at the four corner points did not significantly increase. Smoke patters also showed that the open inlet of the chamber had no effect on improvement of ventilation conditions and effectiveness. Conclusions: In this study, the air velocities at six points in the chamber did not significantly increase despite the increase in the mixing factor and flow rates of ventilation in the controlled environment. Therefore, the inflow of outdoor air throughout an open inlet and installation of a forced ventilation system can potentially increase the indoor air velocity and improve ventilation condition without an increase in the mixing factor.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.1
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• pp.45-54
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• 2012

Optimization of the asymmetric trapezoidal fin with various upper lateral surface slope is made using a two-dimensional analytic method. For the fixed fin base height, the optimum heat loss, fin length and effectiveness are represented as inner fluid convection characteristic number, fin base thickness, fin base height, fin shape factor and ambient convection characteristic number. For this optimum procedure, the optimum heat loss is defined as 95% of the maximum heat loss from the fin. One of the results shows that optimum heat loss and effectiveness seems independent of the fin shape factor while optimum fin length decreases almost linearly as the fin shape factor increases.

• Journal of The Korea Institute of Healthcare Architecture
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• v.27 no.2
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• pp.49-56
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• 2021

Purpose: This study aims to provide a way to improve hospital satisfaction through improvement of hospital bulletins based on the analysis of the actual condition of hospital bulletins and satisfaction analysis for patients. Methods: First, a case study is conducted. After setting the analysis items based on previous studies and case study, a satisfaction survey is conducted on patients and statistical analysis is performed. Results: As a result of factor analysis, factors were classified into four categories: legibility, visibility, effectiveness, and frequency. As a result of the importance analysis through multiple regression analysis of four factors affecting hospital satisfaction, the importance of the "legibility" factor was the highest, followed by the "frequency", "effectiveness", and "visibility". As a result of the satisfaction analysis of the bulletins in the study site, the "visibility" factor was the highest, followed by "legibility", "effectiveness", and "frequency". Implications: In order to improve hospital satisfaction, the improvement of factors of high importance should be considered first. In other words, in hospital bulletins, legibility and frequency should be considered first. In addition, hospital satisfaction can be maximized by improving the level of factors and variables that are low in the satisfaction survey by factor.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.510-516
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• 1988

The effects of input substrate concentration and dilution rate on mass transfer resistance in the operation of immobilized cell reactors were investigated using Rhodospirillum rubrum KS-301 immobilized by Ca alginate as reactor element and glucose as growth-limiting substrate. The kinetic parameters were obtained to estimate effectiveness factors. In the packed-bed reactor, internal mass transfer resistance was predominating although external resistance could not be neglected. The overall effectiveness factor was decreased with increase of dilution rate. In the continuous stirred-tank reactor, external resistance was nearly neglected and the overall effectiveness factor was not affected by dilution rate. In this experiment the overall effectiveness factors in PBR and CSTR were estimated to be 0.70 and 0.71 at D$_{i}$ = 0.2/h, R = 0.15 cm, and S$_{i}$ : 1.0g/L, respectively.

• Earthquakes and Structures
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• v.20 no.2
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• pp.133-148
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• 2021

The paper presents a simplified force-based seismic design procedure for the preliminary design of steel haunch retrofitting for the seismic upgrade of deficient RC frames. The procedure involved constructing a site-specific seismic design spectrum for the site, which is transformed into seismic base shear coefficient demand, using an applicable response modification factor, that defines base shear force for seismic analysis of the structure. Recent experimental campaign; involving shake table testing of ten (10), and quasi-static cyclic testing of two (02), 1:3 reduced scale RC frame models, carried out for the seismic performance assessment of both deficient and retrofitted structures has provided the basis to calculate retrofit-specific response modification factor Rretrofitted. The haunch retrofitting technique enhanced the structural stiffness, strength, and ductility, hence, increased the structural response modification factor, which is mainly dependent on the applied retrofit scheme. An additional retrofit effectiveness factor (ΩR) is proposed for the deficient structure's response modification factor Rdeficient, representing the retrofit effectiveness (ΩR=Rretrofitted /Rdeficient), to calculate components' moment and shear demands for the retrofitted structure. The experimental campaign revealed that regardless of the deficient structures' characteristics, the ΩR factor remains fairly the unchanged, which is encouraging to generalize the design procedure. Haunch configuration is finalized that avoid brittle hinging of beam-column joints and ensure ductile beam yielding. Example case study for the seismic retrofit designs of RC frames are presented, which were validated through equivalent lateral load analysis using elastic model and response history analysis of finite-element based inelastic model, showing reasonable performance of the proposed design procedure. The proposed design has the advantage to provide a seismic zone-specific design solution, and also, to suggest if any additional measure is required to enhance the strength/deformability of beams and columns.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.12
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• pp.2150-2156
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• 2007

According as level of industry develops day after day, electricity load system of industry requires high level control, effectiveness and high efficiency. Among supply and control unit of suitable power supply in these load characteristic, inverter systems of constant current regulate is used widely control of lighting and electric heating system. But, problems that power factor deterioration and fast response of control, efficiency, harmonics and etc are still remain. Therefore, in this paper proposed an inverter systems with constant current regulation and power factor correction (PFC) circuit for lighting and beaconing of aerodromes. The effectiveness of the proposed system confirmed through experimental results of 10[kW] power supply system.