• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.7
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• pp.117-123
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• 2007

This paper is about the economic analysis of the replacement of electric facilities in the production facilities. As the interest of energy is increasing, the efficiency of facilities become more important. So, in this paper, we diagnosed facilities, especially electric motors, in the plant and calculated the operating efficiency, power loss with the load factor. And when we replace these facilities into high-efficiency motors, we also calculated new energy efficiency, energy loss and economic analysis through capital recovery factor. As a result, we economically proved that using high-efficiency motor is more beneficial than using non-high-efficiency motors in the model process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.400-413
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• 2017

It is necessary for inmates released from prison to recover their career capital in order to function normally in society. Failure to adapt to the society may not only make them unhappy but could also aggravate social safety nets. Therefore, it is critical to examine the recovery of career capital. For this study, we conducted in-depth interviews of 10 rehabilitation recipients who were supported by Korea Rehabilitation Agency. For qualitative analysis, several career topics were analyzed, such as obstacles in recovering career capital, efforts in overcoming these obstacles, what is helpful for them to overcome the obstacles and what is required for them to adapt to the career life and others. Analysis results found that the rehabilitation beneficiaries suffered loses to their career capital due to their incarceration, suffered from the loss of pride and became despondent in the process of recovery of career capital due to the negative social perception toward their social self, fear of social stigma and devaluation of themselves. In addition, the fear of possible negative evaluation was a critical factor in making their social activities more challenging. Conversely, it was found that social support in the recovery process of career capital has a positive effect. In particular, emotional support from spouses, employers, family members and friends are the most positive factors. Concerning efforts at adapting to careers, it was found that an active, leading and positive attitude toward the career were critical, showing that positive evaluation and recognition in family and social relations and the experience of success in the career were positive elements in enhancing a sense of pride. In summary, it was found that in the recovery process of career capital, dysfunctional beliefs had a negative effect, while social support had a positive effect, on the recovery of career capital.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.5
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• pp.199-204
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• 2000

This paper presents new approaches for the calculation for the calculation of each user's wheeling prices based on the economic analysis method with focus on the postage stamp rule. The suggested postage stamp rules can overcome the following problems embedded in the conventional accounting-costs-based methods such as the volatileness of wheeling prices depending deprieciation methods, emerging the wheeling free-riders due to the difference between accounting life-time and technical life-time, price discrimination between firm and non-firm network users, etc. To solve these problems we suggest new postage stamp rules employing capital recovery factor for investment costs treatment and applying technical life-time. Furthermore, we have suggested a new formulation for non-firm wheeling users based on the wheeling energies. In the case study, the results of suggested postage stamp methodologies are compared with those of conventional approaches.

• Plant Journal
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• v.17 no.2
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• pp.48-53
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• 2021

In the case of a 900 MW combined cycle power plant, most of the load on the site is a rotating device and is operated at a low power factor, and the power factor decrease increases the reactive power, which causes the efficiency of the device to be consumed and unnecessary unnecessary power consumption. This study intends to present the results by installing and operating a reactive power compensation device that absorbs and removes reactive power, which is a solution to this problem, on a 6.9 kV on-board bus. As a result of application of this system, first, it was confirmed that the power factor of the rotating machine was improved to 0.22 and the load power in the house was reduced by 1.4%, and the thermal efficiency of the generator was increased by 0.1% and the power generation power by 810 kW. Next, it was confirmed that the cost of construction and operation can be reduced in the future due to economic feasibility, with a decrease of 200 million won/year in electricity loss compared to 1.5 billion won in investment, an increase of 1 billion won/year in sales, and a one-year capital recovery period.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.67-76
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• 2022

COVID-19 struck labor markets around the world, exposing and exacerbating the gender inequalities within the human capital structure. The last, in its turn, jeopardizes the return of the national economies to the growth trajectory undermined by pandemic impact. The authors assume that COVID-19 disproportionately affected the employment rates of women and men, which led to increased gender inequality in the labor market, which, in turn, affected GDP growth rates in the EU. To prove this hypothesis two research questions are discovered: 1) whether there was a different correlation between the number of COVID-19 cases in the EU and indicators of the labor market for women and men; and 2) whether there was a link between the growth of gender inequality in the EU labor market and the GDP dynamics in these countries. The analysis of the correlation between the number of cases of COVID-19 and indicators of the labor market in the EU revealed faster growth of women's unemployment rates compared to men's ones as the COVID-19 incidence unfolded. Multiple linear regression and factor analysis have been used to investigate the influence of gender inequality in the labor market on GDP dynamics. Despite the methodological limitations, the proposed model is both a sound argument and an analytical basis in favor of gender-responsive economic recovery backed by the systematic and consistent gender equality policy of a government.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.6
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• pp.1046-1052
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• 2010

In residential house, photovoltaic (PV) system among various alternatives in renewable energy system is the most efficient and feasible solution for reducing energy consumption and electricity cost. However, relatively high initial cost make people reluctant to install PV system in their houses. Therefore, in the initial state for PV system installation in the house, it is very important to decide proper capacity of the PV system considering the expected energy usage and solar energy supplying condition with the house. This paper proposes a novel optimization model for deciding appropriate capacity of the PV system for residential house. The objective function of the model is to minimize the annual cost including electricity bill, operation and maintenance cost, and annual fixed cost calculated from the initial installation cost based on capital recovery factor (CRF). The model also shows the optimal inclining angle of PV panels of the system. In this paper, we estimate the PV output using PVWATTS (PV simulator of Office of Energy Efficiency and Renewable Energy) and find optimal solutions by Sequential Quadratic Programming (SQP) method using MATLAB software. The proposed approach is finally applied to a residential model house in Gangneung, Gangwon-Do and verified its feasibility for adopting to PV system design for residential houses.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.23-31
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• 2011

The wind energy is one of the most prospective resources in renewable energy. However, the WTGS shouldn't be installed indiscriminately because the power system can be negatively influenced by a variable and uncertain nature of the wind energy. It is the reason why it has to be limited to install the WTGS thoughtlessly mentioned above that support the importance of the maximum penetration limit of wind power. It may required that power system operators suggests a new way of power system operation as percentage of the WTGS increase in the existing power system. The wind power is fixed in a limited area, so using rate of the wind power will be increased by installing additional WTGS. In this paper, we have studied on economic evaluation of the wind capacity increased by restricting the output of the WTGS as the way to increase the wind capacity.

• Journal of the Korean Society of Food Culture
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• v.35 no.2
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• pp.156-166
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• 2020

In this study, 594 questionnaires administered to men and women residing in the capital metropolitan area who work night shifts were analyzed in order to study the effect of health information cognition on healing needs in accordance with the type of food selection criteria of the night worker. The results of confirmatory factor analysis in deriving food selection type identified four categories, a safety seeking type, a food exploratory type, a habitual seeking type, and a rational type, and the cognition types on health information were classified into physical cognition and psychological cognition. The need for healing, which was the investigated factor, was found to have a high correlation between questionnaire items with high reliable consistency. The results of this study were as follows. First, the food selection types of safety seeking type and habitual food seeking type had significant positive effects on the cognitive level of physical health information, and food exploratory type and habitual seeking type had significant positive effects on the cognitive level of psychological health information. In addition, it was shown that food exploratory type and rational type had significant positive effects on healing needs. As a result of this study, it was found that the cognition level of physical and psychological information was different according to food selection type, and the higher the cognitive level, the higher the healing needs. In particular, the result that the level of psychological health information significantly affected healing needs signifies that there is a demand to develop programs and menus that satisfy various needs related to healing and recovery from fatigue. In addition, further interest and study on the health and healing of night workers are required.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4D
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• pp.357-366
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• 2012

Construction equipment has applied to depreciation over the years, however, the price index for construction equipment is not properly reflected in existing quantity per unit and the local tax law. Thus, this study shows the analysis of the corporate tax law, the local tax law and business accounting standards, characteristics of the domestic depreciation system and depreciation methods, and the capital recovery factor of construction equipment applying the theory for economic efficiency. It also presents cases of depreciation on the basis of quantity per unit and tax law using straight-line depreciation method and declining balance method. It is proposed that the relations of the application system of permissible period for construction equipment and the existing system be explained and the application system of permissible period for construction equipment be imposed. Furthermore, it proposes the development of depreciation tables of construction equipment monthly expenses based on the domestic price index and applications. In addition of that, it proposes the analysis of pros and cons of the methods suggested and application limits of the study and subsequent improvement plans. This study should reflect more rational and objective reality in quantity per unit and tax law.

• Journal of Hydrogen and New Energy
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• v.30 no.1
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• pp.21-28
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• 2019

Reversible solid oxide fuel cell (ReSOC) system was integrated with waste steam for electrical energy storage in distributed energy storage application. Waste steam was utilized as external heat in SOEC mode for higher hydrogen production efficiency. Three system configurations were analyzed to evaluate techno-economic performance. The first system is a simple configuration to minimize the cost of balance of plant. The second system is the more complicated configuration with heat recovery steam generator (HRSG). The third system is featured with HRSG and fuel recirculation by blower. Lumped models were used for system performance analyses. The ReSOC stack was characterized by applying area specific resistance value at fixed operating pressure and temperature. In economical assessment, the levelized costs of energy storage (LCOS) were calculated for three system configurations based on capital investment. The system lifetime was assumed 20 years with ReSOC stack replaced every 5 years, inflation rate of 2%, and capacity factor of 80%. The results showed that the exergy round-trip efficiency of system 1, 2, 3 were 47.9%, 48.8%, and 52.8% respectively. The high round-trip efficiency of third system compared to others is attributed to the remarkable reduction in steam requirement and hydrogen compression power owning to fuel recirculation. The result from economic calculation showed that the LCOS values of system 1, 2, 3 were 3.46 ¢/kWh, 3.43 ¢/kWh, and 3.14 ¢/kWh, respectively. Even though the systems 2 and 3 have expensive HRSG, they showed higher round-trip efficiencies and significant reduction in boiler and hydrogen compressor cost.