• Journal of Environmental Science International
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• v.18 no.8
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• pp.867-876
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• 2009

Although renewable power is regarded a way to active response to climate change, the stability of whole power system could be a serious problem in the future due to its uncertainties such as indispatchableness and intermittency. From this perspective, the peak time impact of stochastic wind power generation is estimated using simulation method up to year 2030 based on the 3rd master plan for the promotion of new and renewable energy on peak time. Result shows that the highest probability of wind power impact on peak time power supply could be up to 4.41% in 2030. The impact of wind power generation on overall power mix is also analyzed up to 2030 using SCM model. The impact seems smaller than expectation, however, the estimated investment cost to make up such lack of power generation in terms of LNG power generation facilities is shown to be a significant burden to existing power companies.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.1
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• pp.25-29
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• 2000

The present study evaluated the body burden of aromatic VOCs in roadside and underground storekeepers. The Method Detection Limit(MDL) of the analytical system ranged from 0.2 to 0.4$\mu\textrm{g}$/m3 for the target VOCs. The recovery of the sampling system for the compounds was above 80%. For all the target compounds, the breath concentrations of the smokes were similar to or slightly higher than those of the nonsmokers for both the roadside and underground storekeepers. For Ethylbenzene, p-Xylene, and o-Xylene, the breath concentrations of the underground storekeepers were somewhat higher than those of the roadside storekeepers. In contrast, the breath m-xylene concentration of underground storekeepers was similar to that of roadside storekeepers. For both the roadside and underground storekeepers, the breath concentrations prior to and after work were not significantly different.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.5-10
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• 2022

Photovoltaic systems provide a reliable green energy solution. The sustainability and low-maintenance of Photovoltaic systems motivate the integration of Photovoltaic systems into the electrical grid and further contribute to a greener environment, as the system does not cause any pollution or emissions. Developing methodologies based on machine learning techniques to assist in reducing the burden of studies related to integrating Photovoltaic systems into the electric grid are of interest. This research aims to develop a methodology based on a unsupervised machine learning algorithm that can reduce the burden of extensive studies and simulations related to the integration of Photovoltaic systems into the electrical grid.

• Journal of Korean Public Health Nursing
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• v.26 no.3
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• pp.440-452
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• 2012

Purpose: The purpose of this study was to provide basic data for use in development of strategy for healthy aging preparation and successful transfer to old age by identifying factors influencing quality of life of the baby boom generation. Methods: The data were collected from a total of 205 members of the baby boom generation(aged 48 to 56), and analysis was performed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression using the SPSS(Version19.0) program. Results: Burden for taking care of children, aging anxiety, preparations for old age, and quality of life according to the general characteristics and health-related characteristics commonly showed a significant difference in education level and presence of stress. The greater the more burden for taking care of children and the deeper the aging anxiety, the lower the quality of life, and the better prepared for aging, the higher the quality of life. Factors affecting quality of life in the baby boom generation included preparations for old age, burden for taking care of children, monthly household income, and quality of sleep. Explanatory power was 32%. Conclusion: For successful transition to old age and for improvement of quality of life in the baby boom generation, a comprehensive approach in micro and macro dimensions will be sought.

• Progress in Superconductivity and Cryogenics
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• v.23 no.3
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• pp.51-54
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• 2021

The DC system has less power loss compared to the AC system because there is no influence of frequency and dielectric loss. However, the zero-crossing point of the current is not detected in the event of a short circuit fault, and it is difficult to interruption due to the large fault current that occurs during the opening, so the reliability of the DC breaker is required. As a solution to this, an LC resonance DC circuit breaker combined a superconducting element has been proposed. This is a method of limiting the fault current, which rises rapidly in case of a short circuit fault, with the quench resistance of the superconducting element, and interruption the fault current passing through the zero-crossing point through LC resonance. The superconducting current limiting element combined to the DC circuit breaker plays an important role in reducing the electrical burden of the circuit breaker. However, at the beginning of a short circuit fault, superconducting devices also have a large electrical burden due to large fault currents, which can destroy the element. In this paper, the reactor is connected to the source side of the circuit using PSCAD/EMTDC. After that, the change of the fault current according to the reactor capacity and the electrical burden of the superconducting element were confirmed through simulation. As a result, it was confirmed that the interruption time was delayed as the capacity of the reactor connected to the source side increased, but peak of the fault current decreased, the zero-crossing point generation time was shortened, and the electrical burden of the superconducting element decreased.

• Women's Health Nursing
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• v.28 no.3
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• pp.197-209
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• 2022

Purpose: This study aimed to investigate family functioning among spouses of gynecologic cancer patients in Korea. McCubbin and McCubbin's Family Resilience Model (1993) guided the study focus on burden of care, family resilience, coping, and family functioning. Methods: An online survey collected data from 123 spouses of gynecologic cancer patients through convenience sampling from online communities for gynecologic cancer patients in Korea. Burden of care, family resilience (social support, family hardiness, and family problem-solving communication), coping, and family functioning were measured by self-report. Results: The patients (44.7%) and their spouses (47.2%) were mostly in the 41 to 50-year age group. Stage 1 cancer was 44.7%, and cervical cancer was the most common (37.4%) followed by ovarian cancer (30.9%) and uterine cancer (27.6%) regarding the cancer characteristics of the wife. Family function, burden of care, family resilience, and coping were all at greater than midpoint levels. Family functioning was positively related with social support (r=.44, p<.001), family hardiness (r=.49, p<.001), problem-solving communication (r=.73, p<.001), and coping (r=.56, p<.001). Multiple regression identified significant factors for family functioning (F=25.58, p<.001), with an overall explanatory power of 61.7%. Problem-solving communication (β=.56, p<.001) had the greatest influence on family function of gynecologic cancer families, followed by coping (β=.24, p<. 001) and total treatment period of the wife (β=.17, p=.006). Conclusion: Nurses need to assess levels of family communication and spousal coping to help improve gynecologic cancer patients' family function, especially for patients in longer treatment.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1351-1354
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• 2002

Wind farm which are composed with wind turbine generators can be a good alternatives to solve environmental problem and solutions to cope with energy crisis for using wind energy. Until now, these wind turbine generators have been being studied on the viewpoint of only active power control for reducing the burden of main grid. In this control scheme, we might demand a reactive power compensator in order to make reparation for the reactive power produced from wind turbine generator itself. Therefore, if the reactive power as well as active power of wind turbine generator were controlled according to the demand of reactive power, the installation of a additional reactive power compensator could be reduced. This paper presents the control method of a active and reactive power for wind turbine generators by means of SVPWM(Space Vector Pulse Width Modulation) inverting method and describes a operational coordination of wind turbine generators. The proposed power control algorithm can simply produce the output power of wind turbine generator needed in wind farm, which can reduce the power of main grid more and exclude a supplementary reactive power compensator. We assumed that wind farm are composed with two kinds of wind turbine generators, AC/DC/AC and induction generator types.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.6-8
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• 2002

In this paper present Autonomous Adaptive Digital Over Current Relay which acts autonomous setting using voltage and current measured by relay in the change of power systems. Automation of relay setting is required for distribution automation although manual relay setting is used at present. This paper presents Autonomous Relay Setting which knows change of the power system and acquires setting element using the Recursive Least Squares. Relay setting is very difficult work. But proposed relay is expected to decrease burden of relay setting using acquired information of power system change and autonomous setting. Also fast protective ability is expected according to change of power system.

• Journal of Electrical Engineering and Technology
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• v.4 no.3
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• pp.301-309
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• 2009

A simple and efficient Lambda logic (${\lambda}-logic$) based algorithm is proposed for the solution of the generator constrained economic dispatch problem when the generating units having prohibited zones. The proposed method solves the economic dispatch (ED) problem that takes into account ramprate limits, transmission losses and prohibited operating zones in the power system operation. The proposed method uses a simple heuristic rule based on average power of prohibited operating zones which produces the feasibility of solution for the restricted operating units. The effectiveness of the algorithm is tested on five different test systems and the performance compared with other relevant methods reported in the literature. In all the cases, the proposed algorithm performs better than the previous existing algorithms with a less computational burden.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.174-174
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• 2004

It is necessary to perform the radionuclide inventory assessment for the disposal of low and intermediate radioactive waste containers. The $\gamma$ nuclide analyzer can be used for the assessment of containers. However, if the radioactivity in the containers is extremely low or high, radionuclide inventory of the containers can not be evaluated properly. Also, gamma scanning method is time consuming and has economical burden to the utilities.(omitted)