• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.1
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• pp.141-156
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• 2011

In this paper we develop a link cost function for data delivery in sensor network. Usually most conventional methods determine the optimal coefficients in the cost function without considering the surrounding environment of the node such as the wireless propagation environment or the topological environment. Due to this reason, there are limitations to improve the quality of data delivery such as data delivery ratio and delay of data delivery. To solve this problem, we derive a new cost function using the concept of Partially Connected Neural Network (PCNN) which is modeled according to the input types whether inputs are correlated or uncorrelated. The correlated inputs are connected to the hidden layer of the PCNN in a coupled fashion but the uncoupled inputs are in an uncoupled fashion. We also propose the training technique for finding an optimal weight vector in the link cost function. The link cost function is trained to the direction that the packet transmission success ratio of each node maximizes. In the experimental section, we show that our method outperforms other conventional methods in terms of the quality of data delivery and the energy efficiency.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.8
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• pp.439-447
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• 2009

Cogeneration system produces power as well as heat recovered from waste heat during power generation process. This system has higher energy efficiency than that of the power plant. In this study the optimal design for the cogeneration system with the increase of the capacity considering life cycle cost(LCC) analysis has been performed in the general facilities such as hotels and hospitals under the assumption of electricity cost of 95 won/kWh, the initial cost of cogeneration system of 1,500,000 won!kW and the value of 0.5${\sim}$1.0 in the ratio of heat to power. The optimal ratio of cogeneration capacity divided by average electricity load of facility was found out more than 0.5 in case of electricity cost with the increase of>30%, and the percentage of $CO_2$ reduction was about 9%. The most important factors in the economic analysis of cogeneration system was found out the electrity cost and the initial cost of cogeneration system. Also the ratio of heat to power at the value of>0.5 was not affected in the economy of cogeneration system, but was very important in the $CO_2$ reduction.

• Journal of the Korean Home Economics Association
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• v.37 no.2
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• pp.127-144
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• 1999

The purposes of this study were to identify the housing maintenance cost, imputed rent fee and total housing cost of households living in rental house, to analyze the factors related to their housing maintenance cost, imputed rent fee and total housing cost and to investigate the factors contributing to total housing cost to total household income ratio. The data used for these purposes, was 97 KHPS of Daewoo Economic Research Institute. Sample size of households living in rental house, was 663. Statistics performed for the analysis were frequencies, percentiles, t-test, Lorenz cutie and Gini coefficient, Tobit analysis, OLS and Logistic analysis. The results of this study were as fellows: First, monthly cost of monthly rent & maintenance and repairs of households living in rental house with a deposit was lower than rental house, while the imputed rent fee of households living rental house with a deposit was higher than monthly rent households'And, total housing cost of households living in rental house with a deposit was higher than monthly rent households'. Second, Gini coefficient of the housing maintenance cost was 0.440, Gini coefficient of imputed rent fee was 0.362, and Gini coefficient of total housing cost was 0.291. Third, the variables related to their housing maintenance cost were family type, total household expenditure of socio-demographic characteristics and residence, type of rent, housing type of housing environmental factor. Also, the variables contributing to imputed rent fee were job type and educational attainment of household hearts, the number of family members, total household expenditure, residence, type of rent, housing type and tole number of rooms. In addition, the variables associated with total housing cost were job type and educational attainment of household head, total household income and residence, type of rent, housing type and the number of room. Finally, age, job type, educational attainment of household head, wife's employment status, the number of family members, family type, total household expenditure, residence, rent type of rent, housing type, the size of living space, and the number of room were significant variables contributing to total household cost to total household income ratio.

• Journal of the Korean Solar Energy Society
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• v.32 no.6
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• pp.60-67
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• 2012

Government Geothermal Cooling-Heating Projects has made efforts to reduce GHG(Greenhouse Gas) emissions and to manage cost of greenhouse farm households. This study evaluated the economic benefits of heating load rate of change by comparing Geothermal Cooling-Heating System with the existing system(greenhouse diesel heating) in the Government Geothermal Cooling-Heating Projects. Economic analysis results shows that, 1) When installing the Cooling-Heating system according to the ratio of 70% heating load in policy standards, the geothermal cooling-heating system has economic efficiency with greenhouse type or scale independent because the investment cost is recovered within 7 years. And It was more economic efficiency the ratio of 50% heating load than70% heating load. 2) When installing the Cooling-Heating system according to the glass greenhouse of the ratio of 90% heating load, pay period of investment cost is recovered within 5 years. Therefore it is necessary to apply flexible heating sharing according to greenhouse type or scale.

• Journal of Pharmacopuncture
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• v.24 no.3
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• pp.142-151
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• 2021

Objectives: Although Korean Medicine (KM) subsidized by the National Health Insurance (NHI) has been used for a long time, there has been no active analysis using claims data. Therefore, the purpose of this study was to examine the NHI KM utilization trend using NHI statistics and to measure the level of market concentration by year. Methods: By restructuring the contents of NHI Statistics for Pharmaceuticals for 2010-2019, the claim cases, costs, and annual growth rates of KM were demonstrated by year, sex, age group, region, therapeutic group, and KM treatment. The proportion of highly used k treatments in cost was calculated as the concentration ratio (CR) k and its trend by year was investigated. Results: In 2019, the NHI cost on KM amounted to ₩38.2 billion KRW, increasing by 11.6% per year on average in 2010-2019. Notably, KM was used more frequently among women and patients aged ≥ 65 years, and the mixed formulation accounted for 95% of the total cost of KM. The CR of the simple formulation increased rapidly, whereas that of the mixed formulation remained constant. In 2019, three simple formulation treatments- peony, licorice, and ginseng- accounted for 93.8% of the total cost for KM (CR3 = 93.8%). Conclusion: NHI KM is rapidly increasing. Investigating the CR of KM confirmed that KM prescriptions have been concentrated in small numbers over the past 10 years.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.36 no.3
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• pp.147-157
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• 2020

With the increasing obligation to reduce greenhouse gas emissions to the building sector, the government has been gradually expanding its obligation to zero-energy buildings since 2020. Since the ZEB certification took effect in 2017, 48 preliminary and main certifications have been completed as of March 2019, and most of them are public buildings or even certified, but have earned Grade 5 of ZEB. This means that compared with the number of annual building permits registered in Korea, the figure is insignificant, and that it receives little if not mandatory. Therefore, this study investigated empirical cases of ZEB additional construction cost and conducted cost benefit analysis according to changes in ZEB additional construction cost based on a preliminary feasibility analysis project recently conducted by the KDI. In addition, considering the public buildings, the social costs were considered, and the cost-benefit analysis method was the same as the KDI's preliminary feasibility analysis method. The analysis shows that if the ratio of ZEB additional construction cost is more than 5 percent, it is analyzed that there is no economic feasibility, and considering that the ratio of additional construction cost in the cases of ZEB in Korea is 17 percent to 38 percent, it will not be easy to obtain ZEB certification in terms of cost. Finally, to narrow these differences in cost and economic aspects, the overseas low energy and ZEB incentive examples proposed measures such as the concept of subsidy payment in Illinois and the compensation of social costs to private ZEB.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.2
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• pp.13-25
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• 2022

Purpose : This study compared the cost-effectiveness ratio of physical therapy in health centers and home physical therapy, two physical therapy methods for home-bound stroke patients, and clarified the economic validity regarding the effect of home physical therapy. Methods : To measure and compare the cost and effectiveness of the two physical therapy methods for stroke patients, subjects were recruited based on in-hospital and home physical therapy. Among the entire data collected, 82 and 90 participants were selected for in-hospital and home physical therapy, respectively. To measure costs, regarding both in-hospital and home physical therapy, direct cost and indirect cost for patients, family, medical institutes, and the government were measured. In addition, activities of daily living were measured in both methods to measure their effectiveness. Through collected data, the cost-effectiveness and incremental cost-effectiveness ratios were analyzed. Results : Based on the analysis of cost-effectiveness, home physical therapy showed lower cost-effectiveness than in-hospital physical therapy. Furthermore, the incremental cost-effectiveness ratio also showed a difference, which implied home physical therapy could have high effectiveness compared to cost. Conclusion : Based on these results, home physical therapy could be considered as an alternativeto other methods of physical therapy, for home-bound stroke patients. In addition, the result of thisstudy contribute by providing evidence that home physical therapy offers economic benefits and canbe more effective in treating home-bound patients when policy decisions are made to establish a home physical therapy system.

• Journal of Environmental Impact Assessment
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• v.23 no.1
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• pp.11-17
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• 2014

Since the Renewable Portfolio Standard (RPS) would be started in 2012, the use of renewable energy should be 11% of total energy use including bio-fuel in 2030. The economic efficiency for renewable energy in B power plant was considered with the bio-diesel, wind power and solar power. The Net Present Value (NPV) and Benefit/Cost Ratio(BC) were used for the economic efficiency with the cost and benefit analysis. In case of bio-diesel, the cost resulted from the fuel conversion and the benefit would be created with trade and environmental improvement. With regard to wind power and solar power, the construction cost would be required and benefit factors would be same as the bio-diesel. The wind power was the best of economic efficiency of renewable energy as the results of NPV and BC ratio. Whereas, the market of wind power was very popular and the techniques of wind power has been developing rapidly.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.39-43
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• 1995

The purpose of this article was to understand the individual proportion of quality costs which have been expended by manufacturing industries in Seoul and Kyunggido district. The collected data on 72 firms could be use for an empirical analysis and the ratio test was implementented with the questionnaires. The finding were as following : by conparison with the proportion of quality cost in typical manufacturing industrial of U.S., We concluded that total quality cost was occupied with a small portion of sale. Also as compared with the individual item of quality cost, it was noted that the proportion of prevention cost had increased in a relatively large company.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.46-52
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• 2012

The purpose of this study is to give ROI informations about management status and investment returns to someone who will newly cultivate lycium chinese miller or expand area of its cultivation. In this study, IRR, B/C Ratio and NPV is used for ROI analysis. We basically surveyed fifty two among Lycium Chinese Miller cultivation farmhouses in chief producing districts Chungnam Chungyang, Jeonnam Jindo in Korea from May until September in 2009. Hence, this study surveyed these farmers about production cost, management cost, input labors and materials, land price and etc. by working process to calculate production and operation cost. As the result of farm survey, average selling price of Lycium Chinese Miller is 15,000 won per kg at locals for five years. However, when 3% discount rate is applied, the result of the analysis is B/C Ratios 0.89, which shows unprofitable. Therefore, it is a possible baseline that price of Lycium Chinese Miller is at least 16,800 won per kg with 3.00% IRR and B/C Ratio is 1.00. It could be profitable with about 21.75% income ratio when price of Lycium Chinese Miller is 16,800 won per kg.