• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2303-2308
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• 2010

We studied the cost-volume supply characteristic of public transportation systems focused on Bi-modal Tram in the main cities to analyze the applicability and status for the new transit system Bi-modal Tram as public transportation system. The operation cost considering the characteristic of vehicle, facilities, operation and average cost for respective public transportation system and the time cost considering the travel and transfer time are defined to the social cost, and the cost-volume supply curve is based on this social cost. The cost-volume supply characteristic between public transportation modes in the city is determined on the basis of cost-volume supply curve. Through the comparison between cost-volume supply characteristic of main transportation systems, it is analyzed about the relation between public transportation systems in the city and the characteristic for proper service provision. The application of Bi-modal Tram in the city is concluded that it is effective to reduce the social cost on the existing public transportation system.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.6
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• pp.707-714
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• 2022

Hydrogen production using solid oxide electrolysis cells (SOEC) is a promising technology because of its efficiency, cleanness, and scalability. Especially, high-power SOEC system has received a lot of attention from researchers. This study compared and analyzed the low-power and high-power SOEC system in term of economic. By using revenue requirement method, levelized cost of hydrogen (LCOH) was calculated for comparison. In addition, the sensitivity analysis was performed to determine the dependence of hydrogen cost on input variables. The results indicated that high-power SOEC system is superior to a low-power SOEC system. In the capital cost, the stack cost is dominant in both systems, but the electricity cost is the most contributed factor to the hydrogen cost. If the high-power SOEC system combines with a nuclear power plant, the hydrogen cost can reach 3.65 $/kg when the electricity cost is 3.28 ¢/kWh and the stack cost is assumed to be 574 $/kW.

• IE interfaces
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• v.18 no.4
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• pp.477-484
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• 2005

This paper is concerned with the life-cycle cost(LCC) of the urban transit system which was developed by KRRI and is now under test in Gyeongsan, Korea. Its reliability, availability and maintainability(RAM) were analyzed. LCC is the core part of analyzing the total cost of acquisition and ownership of a system. LCC analysis of a system is the most effective when it is applied in the it's early design phase. In this paper, we present IEC 60300-3-3(Life Cycle Costing) in detail and propose how to apply LCC in assessing the urban transit system according to RAM process. This case study demonstrates that reliability management system is very effective in reducing the operating cost of subway corporations in Korea.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.377-377
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• 2000

Current software cost estimation models, such as the 1951 COCOMO, its 1987 Ada COCOMO update, is composed of nonlinear models, such as product attributes, computer attributes, personnel attributes, project attributes, effort-multiplier cost drivers, and have been experiencing increasing difficulties in estimating the costs of software developed to new lift cycle processes and capabilities. The COCOMO II is developed fur new forms against the current software cost estimation models. This paper provides a case-based analysis result of the cost driver in the software cost models, such as COCOMO and COCOMO 2.0 by fuzzy and neural network.

• Korea Journal of Hospital Management
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• v.28 no.1
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• pp.1-13
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• 2023

Purpose: This study purposed to analyze the economic feasibility of introducing a third party logistics system as a strategic alternative to hospital management. Methods: Economic analysis was performed by measuring changes in costs and benefits before and after implement the third party logistics system and estimating the size of net benefits for the next five years for the target hospital. A questionnaire survey and in-depth interview with stake-holders were conducted to find out the satisfaction and effectiveness of the system. Findings: According to results, the cost-benefit ratio for the implementation of the system was 1.18. For the next five years, the cost-benefit ratio was 1.48, the net present value was about 1.7 billion won, and the internal rate of return was 64%. The satisfaction of internal stake-holders was relatively high, in terms of improving the concentration of unique tasks and increasing the efficiency of inventory management. Practical Implications: It was found that the increase in benefits had a greater effect on the change in the cost-benefit ratio than the increase in costs resulting from the expansion of logistics, and the increase in the present value of net benefits gradually decreased as the cost increased. In addition, overall job satisfaction and satisfaction with outsourcing companies were relatively low, which means that stabilization of the new system is important. Further study is needed for more accurate economic analysis.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.246-252
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• 2017

In the defense acquisition, a company's goal is to maximize profits, and the government's goal is to allocate budgets efficiently. Each year, the government estimates the ratio of indirect cost sector to defense companies, and estimates the ratio to be applied when calculating cost of the defense articles next year. The defense industry environment is changing rapidly, due to the increasing trend of defense acquisition budgets, the advancement of weapon systems, the effects of the 4th industrial revolution, and so on. As a result, the cost structure of defense companies is being diversifying. The purpose of this study is to find an alternative that can enhance the rationality of the current methodology for estimating the ratio of indirect cost sector of defense companies. To do this, we conducted data analysis using the R language on the cost data of defense companies over the past six years in the Defense Integrated Cost System. First, cluster analysis was conducted on the cost characteristics of defense companies. Then, we conducted a regression analysis of the relationship between direct and indirect costs for each cluster to see how much it reflects the cost structure of defense companies in direct labor cost-based indirect cost rate estimates. Lastly a new ratio prediction model based on regularized regression analysis was developed, applied to each cluster, and analyzed to compare performance with existing prediction models. According to the results of the study, it is necessary to estimate the indirect cost ratio based on the cost character group of defense companies, and the direct labor cost based indirect cost ratio estimation partially reflects the cost structure of defense companies. In addition, the current indirect cost ratio prediction method has a larger error than the new model.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.389-390
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• 2023

To improve the cost performance of construction sites, various systems and standards are constantly being developed and implemented. Although legal requirements for these system and standard improvements have been increasing, the cost efficiency performance of construction sites remains stagnant. We have digitized documents generated through construction supervision work at 39 building construction sites and proposed a model that can support decision-making in cost efficiency evaluation. This model selects key keywords that are considered to be highly related to cost efficiency by identifying the patterns and relationships of keywords through associated rule analysis and social network analysis using keywords derived from documents. In addition, it is expected to be used as a decision-making aid to determine the cost efficiency of a specific building construction site by establishing a logistic regression model using core keywords. As a systematic database of construction supervision documents and an integrated system of massive data generated by digital technology are established in the future, the accuracy and reliability of the cost efficiency evaluation model are expected to be reinforced.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.2
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• pp.156-164
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• 2005

A comparative analysis of an ice storage system has been performed on the operation cost for the four control strategies, i.e., chiller priority and chiller downstream, chiller priority and chiller upstream, storage priority and chiller upstream, storage priority and chiller downstream. Main components of the ice storage system are an ice-on-coil storage tank and a screw compressor chiller. With the simulation program, the operation cost has been evaluated from the economics of an ice storage system. It is found that the operation cost of the ice storage system is strongly dependent on the control strategy, i.e., chiller priority or storage priority, but less affected by the arrangement method, i.e., chiller upstream or chiller downstream. In case of the maximum load day, the control strategy with chiller priority and chiller upstream is supposed to obtain the reduction of operation cost. However, it is found that the control strategy with storage priority and chiller downstream is the best economical operation for most summer seasons except the maximum load day.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.12
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• pp.1830-1835
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• 2017

8200 Series Electric Locomotives are mostly imported from overseas due to aging and uncertainty of source technology, and it's the maintenance cost is increasing. We are analyzed life cycle costs based on international standards such as IEC 60300-3-3 and IEC62278. The main conversion system of the 8200 series electric locomotive is closely related to vehicle operation and is one of the subsystems requiring frequent maintenance. In this paper, the life cycle cost of the main conversion unit in 8200 series electric locomotive is analyzed based on the maintenance manual. As a result of analysis, maintenance cost of GTO module and control device is relatively high, and it is confirmed that the cost increases according to the useful life.

• Korean Journal of Computational Design and Engineering
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• v.15 no.4
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• pp.261-270
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• 2010

These days, architectural projects are becoming larger and more complex. And lots of information occurs through each phases and areas. For these reason, it is emphasized that collaboration with other parts. Therefore we need more effective architectural design process. However, it is difficult to collaborate in early stage with existing design process and it causes unnecessary spending of time and cost because of 2D-based working system. For solving these problem, we should introduce BIM-based Integrated Design Process which makes it possible to collaborate with other parts from early stage. Now the AEC industry in Korea has been trying to introduce BIM, and promoting variety of related business. However, for actual application of this system, it is unfortunately necessary to change various system throughout the construction industry. And this will cause lots of effort and expense. It is essential that scientific analysis and evaluation of efficiency and validity about this investment, because estimation of the investment and accompanying effects will provide reasonable standard of judgment for investment decision. Thus, this research conducted Cost-Benefit Analysis about BIM-based Integrated Design Process compared to existing design process. It is expected that this paper can be used for preliminary data in the future BIM market.