• Journal of the Korean Operations Research and Management Science Society
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• v.10 no.2
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• pp.1-14
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• 1985

This problem of product selection and princing are considered in congested and uncongested markets. In a congested market, such as a computer service market, product quality (the level of congestion) is partly a function of the amount of usage, which in turn depands on user choice. In an uncongested market, product qualities are set solely by providers. A model of quality and capacity variation is developed using a state equation description to represent user optimizing behavior. The model is used to study the problem of scarce resources among competing user demands through quality-dependent pricing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.1-9
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• 2020

Acritical function of a nation is to protect its people's lives and properties from natural disasters such as a drought. A drought affects many aspects of human life, including social, economic, and industrial activities. Approximately 75.7% of reservoirs in Korea are over 50 years old.Sedimentation over the years may have caused a situation where storage capacity of the reservoirs is no longer sufficient and compliant with the original reservoir specifications. This study analyzes storage capacities for ten aged reservoirs using the autonomous navigation USV. It compares these capacities with sediment estimated by conventional empirical equations. Comparisons were made to the original specifications for the reservoirs.Storage capacity of six reservoirs decreased in a range between 16.2%-55.3% and storage capacity of 4 reservoirs increased in a range between 1.5%-380.2%. This data was compared to data derived from estimating sediment by empirical equations. Yoon's equation(1982) appeared more accurate than Sur's equation(1988) in Uhlinzi and Yongpo reservoirs, and Sur's equation(1988), however, appeared more accurate than Yoon's equation in Daegok, Ugok2 and Ochi reservoirs. The significant ranges of sedimentation shown in this study suggest that it is worth continuously surveying reservoirs to ensure their efficient management and operation.

• Journal of Korean Academy of Nursing Administration
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• v.21 no.3
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• pp.308-316
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• 2015

Purpose: The purpose of this study was to identify the level of project perception for those nurses from research-driven hospitals and to analyze the effect of research-relevant performance in the health care field focusing on the mediated effect of research capacity and job satisfaction. Methods: Data were collected from June, 2014 to July, 2014, and participants were 106 research nurses in Research-driven hospitals. Descriptive statistics, Independent t-test, One-way ANOVA, structural equation modeling (SEM). Results: As a result, Research-relevant performance according to project perception of research nurses from Research-driven Hospitals was not statistically significant, but research capacity and job satisfaction had a mediating role. Evaluation System Perception was significantly different from Research Capacity (p<.001), Research Capacity was significantly different from Job Satisfaction (p<.001), Job Satisfaction was significantly different from Research Performance (p<.001) Conclusion: The results indicate that research capacity building and job security research nurses are able to contribute to improving research performance of research-driven hospitals.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.629-635
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• 2021

This study seeks to examine and analyze the influence of institutional strengthening factors, and capacity building - communication, resources, and training - on the performance of defense policy implementation. This study conducted a quantitative analysis related to the implementation of the institutional strengthening policy. The data used are primary data with a research instrument in the form of a questionnaire. The population in this study were all people in the city of Bandung, Indonesia. The sample of this study consisted of 200 respondents consisting of civilians and soldiers who served in the city of Bandung. Data analysis uses the Structural Equation Model (SEM) measurement model. The results of this study reveals that institutional strengthening (X1) influences positively and significantly capacity building's communication (Y1), resources (Y2), and training (Y3). On the other hand, the performance of defense policy implementation (Y4) is positively and significantly affected by capacity building's communication (Y1), resources (Y2), and training (Y3). The interaction between institutions, consumption support, role of the healthcare sector, and effectiveness are the most important indicators reflecting capacity building (communication, resources, training) and the performance of defense policy implementation. Essentially, this study analyzes the performance of defense policy implementation based on capacity building.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.14.1-14.14
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• 2022

Background: Although spirometry results can be interpreted differently depending on the reference equation used, there are no established criteria for selecting reference equations as part of the special health examinations for Korean workers. Thus, it is essential to examine the current use of reference equations in Korea, quantify their impact on result interpretation, and propose reference equations suitable for Korean workers, while also considering the environmental conditions of special health examination facilities. Methods: The 213,640 results from the special health examination database were analyzed to identify changes in the ratio of measured values to reference values of lung capacity in Korean workers with changes in age or height, and changes in the agreement of interpretations with the reference equation used. Data from 238 organizations that participated in the 2018-2019 quality control assessment by the Korea Occupational Safety and Health Agency were used to identify the spirometer model and reference equations used in each special health examination facility. Results: Korean special health examination facilities used six reference equations, and the rate of normal or abnormal ventilatory diagnoses varied with the reference equation used. The prediction curve of the Global Lung Function Initiative 2012-Northeast Asian (GLI2012) equation most resembled that of the normal group, but the spirometry model most commonly used by examination facilities was not compliant with the GLI2012 equation. With a scaling factor of 0.95 applied to the Dr. Choi equation, the agreement with the GLI2012 equation was > 0.81 for men and women. Conclusions: We propose the GLI2012 equation as reference equation for spirometry in Korean workers. The GLI2012 equation exhibited the most suitable prediction curve against the normal lung function group. For devices that cannot use the GLI2012 equation, we recommend applying a scaling factor of 0.95 to the Dr. Choi equation.

• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.97-102
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• 1999

This study was carried out view that reuse of sludge of adsorbent for benzene in carbonized cast compare with activated carbon. Not only the carbonized cast is good than carbonized carbon in cation exchange capacity and 12 adsorption capacity, but also benzene adsorption capacity is no differences compare to activated carbon. As results, benzene adsorption capacity of carbonized cast and activated carbon are decreased as temperature increase($25~70^{\circ}C$).It is compatible in Lamgmuir model. Therefore, carbonized cast is applied general adsorbent. From experimental results and data regression, in model concerning effect of temperature, relative errors between the experimental data and those calculated by the model are within the range of 1.2~7.8%. In relative humidity effect (RH 0.25~0.50) of benzene adsorption, modified Freundlich model : $QB_{enzene}{;\}QB_{enzene},{\}_{RH=0}=1-kRH^{IN}$, relative errors between the experimental data and those calculated by the model are within are range of 0.5-5.1%. The constants k and l/n in equation were found to be 1.25, 1.89 in carbonized cast.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.9-19
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• 1997

In this paper, the modeling and analysis of dynamic characteristics has been carried out for friction clutches and brakes in an automatic transmission. From the operating oil pressure generated by the valve-body, time delay by check valve and the movement of piston has been examined. Also torque capacity and torque transferred at the clutch is studied. Heat capacity and temperature distribution at the reaction plate of clutch are codeled by time-dependent, nonhomogeneous partial differential equation, and brake torque, brake time, and the amount of heat generated are investigated. It is found that the time delay at the check valve is very short but dominant at the spool.

• Geomechanics and Engineering
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• v.3 no.4
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• pp.285-290
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• 2011

This article employs Multivariate Adaptive Regression Spline (MARS) for determination of friction capacity of driven piles in clay. MARS is non-parametric adaptive regression procedure. Pile length, pile diameter, effective vertical stress, and undrained shear strength are considered as input of MARS and the output of MARS is friction capacity. The developed MARS gives an equation for determination of $f_s$ of driven piles in clay. The results of the developed MARS have been compared with the Artificial Neural Network. This study shows that the developed MARS is a robust model for prediction of $f_s$ of driven piles in clay.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.565-573
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• 2004

This study is to present explicit analytical expressions for calculating bearing capacity factor $N_{\gamma}$, to provide results of the numerical computation instead of the graphical method. In this study, $N_{\gamma}$ is proposed in the critical failure surface on assumption that the center of log spiral in the radial shear zone can be located at the any points of around footing. The critical failure surface is one which yields minimum passive pressure $P_{\gamma}$ on the radial shear zone from the family of log spirals accoding to change of the center of log spiral. This study adoptes Terzaghi's bearing capacity principle(e.g., Prandtl's mechanism, limit equilibrium equation, superposition principle) but the soil wedge in an elastic zone makes angle $45^{\circ}+{\phi}/2$ with the horizontal and the location of the log spiral's center.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.231-231
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• 2009

In this work, we prepared the Ni-loaded porous SBA-15 (SBA-15) by a depositionprecipitation (D-P) method, in order to enhance the hydrogen storage capacity. The structure and morphology of the Ni/SBA-15 were characterized by X-ray diffraction (XRD) and field emission transmission electron microscopy (FE-TEM). The results showed that, at the Ni loading used at the DP times in the range of 0-120 min, SBA-15 preserved the well-ordered hexagonal porous arrangement. The textural properties of the Ni/SBA-15 were analyzed using N2 adsorption isotherms at 77 K. Specific surface area and mesopore volume of the samples were determined from the Brunauer-Emmett-Teller (BET) equation and Barrett-Joiner-Halenda (BJH) method, respectively. The hydrogen storage capacity of the Ni/SBA-15 was evaluated at 298 K/10 MPa. The hydrogen storage capacity of the Ni/SBA-15 was increased in accordance with Ni content. Consequently, it was found that the presence of Ni on mesoporous SBA-15 created hydrogen-favorable sites which enhanced the hydrogen storage capacity by spillover effect.