• Journal of Applied Reliability
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• v.15 no.3
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• pp.145-148
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• 2015

The products to meet the requirement of are installed in nuclear power plant and the reliability target should be provided in the requirement. However, it is not easy to set a reliability target using quantitative analysis. The objective of this paper is to propose a method of reliability target setting considered warranty cost for process controller and then compare a reliability target with reliability analysis result.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.6
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• pp.470-475
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• 2007

The present study has been conducted economic analysis through actual operation of electric heat pump (EHP) and gas engine driven heat pump (GHP) which are installed at the same building in the university. Cost items, such as initial cost, annual energy cost and maintenance cost of each system are considered to analyze life cycle cost (LCC) and economical efficiencies are compared. The initial cost is considered on the basis of actual cost, and annual energy cost is converted into the cost after measuring electricity and gas consumption a day LCC applied present value method is used to assess economical profit of both of them. Variables used to LCC analysis are electricity cost escalation rate, natural gas cost escalation rate, interest rate, and service lives when each of them are 4%, 2%, 8%, and 20 years. The result shows that EHP (148,257,306 won) is more profitable than GHP (161,239,296 won) by 8.05% (12,981,990 won).

• 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 Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1245-1254
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• 2008

Proposing a method for the estimation of the social cost for global warming impact (external cost) is the aim of this paper. Both the endpoint approach and conjoint analysis were applied to estimating the social cost for global warming. The endpoint approach was used to assess the damage on the safeguard subjects by global warming due to the emission of greenhouse gases into the atmosphere. The conjoint analysis was used to estimate the economic values for safeguard subjects which measure the social preferences and willingness to pay (WTP) on safeguard subjects. The economic values of human health and social asset were estimated at 62,261,700 Won / DALY (yr) and 10,000 Won / 10,000 Won, respectively. Moreover, cost factors of GHGs were calculated by multiplying the damage factor which is quantified the unit damage on safeguard subject and the economic value. In the case of CO$_2$, the cost factor was calculated at 13.52 Won / kg (13,520 Won / ton). External cost of products or services can be calculated by multiplying the GHG inventory result of products or services by the cost factor of each GHG. inventory.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.103-112
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• 2017

PURPOSES : In this study, field performance evaluation of crack treatment of pavement and the feasibility of surface treatment of pavement are presented. The performance and cost of preventive maintenance methods have been previously verified, and the methods are being used in many developed countries and cities. However, the performance and cost of the system have not been verified in domestic, field applications. Therefore, in order to improve performance, the field performance is evaluated, and a reasonable cost is proposed. METHODS : Visual Inspection was conducted to evaluate the field application and performance of the preventive maintenance method. In addition, the PCI index was calculated from the results of visual inspection of the application area of the surface treatment method, and the performance life of each method was predicted. For the economic evaluation, life cycle cost analysis was performed using the life cycle cost analysis program. RESULTS :In order to evaluate and quantify the field performance of crack repair material, the residue condition of the pavement surface after crack treatment, rather than the performance of the material, is evaluated. In addition, the crack resistance and performance life of surface treatment methods are evaluated. The cost of currently available treatment methods are compared to the common pavement cut and overlay method, and it is determined that the preventive method is not economical based on life cycle cost analysis. CONCLUSIONS :Because of the characteristics of cracking, it is necessary to conduct the evaluation of currently applied methods and the analysis of the cause of damage, by visual inspection. Moreover, in order to evaluate the performance and economic suitability of the currently applied surface treatment methods, it is necessary to acquire information on application sections by monitoring their long-term conditions and performance.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.109-118
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• 2015

Open raceway ponds are cost-efficient for mass cultivation of microalgae compared with photobioreactors. Although low-cost options like wastewater as nutrient source is studied to overcome the commercialization threshold for biodiesel production from microalgae, a cost analysis on the use of wastewater and other incremental increases in productivity has not been elucidated. We determined the effect of using wastewater and wavelength filters on microalgal productivity. Experimental results were then fitted into a model, and cost analysis was performed in comparison with control raceways. Three different microalgal strains, Chlorella vulgaris AG10032, Chlorella sp. JK2, and Scenedesmus sp. JK10, were tested for nutrient removal under different light wavelengths (blue, green, red, and white) using filters in batch cultivation. Blue wavelength showed an average of 27% higher nutrient removal and at least 42% higher chemical oxygen demand removal compared with white light. Naturally, the specific growth rate of microalgae cultivated under blue wavelength was on average 10.8% higher than white wavelength. Similarly, lipid productivity was highest in blue wavelength, at least 46.8% higher than white wavelength, whereas FAME composition revealed a mild increase in oleic and palmitic acid levels. Cost analysis reveals that raceways treating wastewater and using monochromatic wavelength would decrease costs from 2.71 to 0.73 $/kg biomass. We prove that increasing both biomass and lipid productivity is possible through cost-effective approaches, thereby accelerating the commercialization of low-value products from microalgae, like biodiesel.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.921-926
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• 2007

A dynamic system under random disturbance is considered in the study. In order to control the system efficiently, proper reduction of system dimension is indispensible in design stage. The reduction method using component cost analysis in conjunction with stochastic analysis is proposed for the control of a system. System response is obtained in terms of dynamic moment equation via Fokker-Plank-Kolmogorov(F-P-K) equation. The dynamic moment response of the system under random disturbance are reduced by using of deterministic version of component cost analysis. The reduced system via proposed "stochastic component cost analysis" is successfully implemented for dynamic response and shows remarkable control performance effectively utilizing "stochastic controller" in physical time domain.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.63
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• pp.89-99
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• 2001

This paper proposes assessment of quality management activities based on cost of quality. Cost of quality is considered prevention cost, appraisal cost, internal failure cost, external failure cost in this paper. This paper shows quality cost magement system in thermal power site devision according to activity analysis. Cost of quality in power industries provides a valuable method of both proving the need for improvement and giving a starting point for projects.

• Journal of Navigation and Port Research
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• v.42 no.5
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• pp.331-340
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• 2018

Shipping containers promote rapid development of the transport industry, and generate economic and social value. However, problems often occur due to imbalance in dynamics between exports and imports, container relocation, traffic congestion, and general shipping network designs. So, efficient and cost-effective cargo management has become crucial for the Jeju Island - Mokpo container route (JMCR) in South Korea. Dozens of recent studies reveal that collapsible or foldable containers, may become an innovative solution to problematic issues within the shipping industry. The major purpose of this study is to discuss conditions required for successful commercial application of foldable containers, based on a cost-benefit analysis precisely for the JMCR. Findings reveal usage of foldable containers can be cost-effective, if containers make a "FULL<->EMPTY" route. To the contrary, a "FULL<->FULL" route can drastically increase expenditure. However, economic analysis of actual figures for 2010-2015 indicate that benefits for Mokpo - Jeju direction are significant to cover losses on the Jeju - Mokpo line. Seasonal patterns and mixing percentages of foldable and standard containers on the route, may also produce cost-effective solutions. Sensitivity analysis reveals that benefits from using foldable containers, depend mostly on empty container shares in addition to various extra costs.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.94-98
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• 2014

This study was intend to develop the optimal design method of suspension bridge by the reliability analysis based on minimization of life cycle cost(LCC). The reliability analysis was performed considering aleatory uncertainties included in the result of numerical analysis. The optimal design was estimated based on life-cycle cost analysis depending on the result of reliability analysis. As the effect of epistemic uncertainty, the safety index (beta), failure probability (pf) and minimum life cycle cost were random variables. The high-level distributions were generated, from which the critical percentile values were obtained for a conservative bridge design through sensitivity assessment.