• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.515-518
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• 2007

Because of their low operating and maintaining costs, ground-source heat pump(GSHP) systems are an increasingly popular choice for providing heating, cooling and water heating to public and commercial buildings. Despite these ad- vantages and the growing awareness, GSHP systems to residential sectors have not been adopted in Korea until recently. A feasibility study of a residential GSHP system was therefore conducted using the traditional life cycle cost(LCC) analysis within the current electricity price framework and potential scenarios of that framework. As a result, when the current residential electricity costs for running the GSHP system are applied, the GSHP system has weak competitiveness to conven- tional HVAC systems considered. However, when the operating costs are calculated in the modified price frameworks of electricity, the residential GSHP system has the lower LCC than the existing cooling and heating equipments. The calculation results also show that the residential GSHP system has lower annual prime energy consumption and total pollutant emissions than the alternative HVAC systems considered in this work.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.153-162
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• 1992

A mathematical model for a long range water supply planning is developed as a dynamic capacitated facility location problem, in which operating costs and two types of fixed costs are considered. The fixed costs are for water supply systems such as dams and reservoirs and for water conveyance systems of waterways or conduits from each water supply points. A spreadsheet model is developed to support the efficiency of user interface and to implement a heuristic solution procedure. The proposed solution procedure utilizes SOLVER tool and it has been applied to a system with fictitious data but with reality and applicability in mind. As a result of the mathematical analysis, not only the most economic construction timings of surface water facilities and distribution systems but also the most economical water supply operating patterns are identified.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.19 no.2
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• pp.67-81
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• 1990

The objective of this is to develop a practical software package to calculate annual energy consumption of HVAC (Heating Ventilating, and Air Conditioning) System in a building. It can quickly estimate loads and energy consumption, and have a function of economic analysis through the estimation of operating cost. Techniques of save energy consumption used in a building are necessary from the stage of design process to operation. The single most significant task is on HVAC Systems. Their installation costs, and related operating costs have enormous influence upon initial and maintenance costs. HVAC designers and engineers now have a wide variety of software choices available, but only a few of them have been developed in this country and no source program has been disclosed. Neither load culculation nor estimation of energy consumption is systematically made by the domestic HVAC design firms. Even though computer improved over the years with a trend of large scale load calculation and system selection through simulaion, the utilization of software nowadays does not make good progress due to lack of working environment. Therefore, it is necessary to develop a practical software package with which load calculation can be made with ease and kind manner. This study concerns the development of a software package which makes it possible to design HVAC system and save energy consumption in operation. The algorithm used in this program is a Modified Bin Method widely known as a simplified energy analysis means.

• Information Systems Review
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• v.11 no.3
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• pp.125-146
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• 2009

The emergence of open source software(OSS) with its most prominent advantages creates a vast interest among practitioners. A study on Linux, the most well-known OSS, estimated that it would cost as 5.4 billion Euros taking over 73,000 person-years if it had been developed by conventional means. However, Linux has achieved only 0.65 percent of the operating system market for individual users while Microsoft windows family counts for nearly 90 percent of the market. Much of the effort being spent in the development of OSS is going to waste and potential value that OSS can bring to users is not being realized. Adoption of OSS is often accompanied by the discontinuance of existing software that is already in place. If users resist changing, they may not adopt OSS. Using the case of Linux, this study examines user resistance to change from the commercial operating software to the free operating system. This study identifies six sub-types of switching costs (uncertainty, emotional, setup, learning, lost benefit, and sunk costs) and tests their effects on user resistance to change based on a survey of 201 users. The results show that user resistance to change has a negative impact on the adoption of OSS. Further, this study shows that uncertainty and emotional costs have significant effects on user resistance to change. Beyond previous research on technology adoption, this research contributes towards an understanding of the switching costs leading to user resistance to change and offers suggestions to OSS practitioners for developing strategies to improve the adoption of OSS.

• Journal of the Korea Safety Management & Science
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• v.21 no.4
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• pp.75-80
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• 2019

Sales of the Korean clothing industry grew to 16.9 percent on-year in 2010, but the growth rate dropped to 3 percent from 2011 to 2016 and the overall market began to slump to 1.1.6 percent in 2017. The competitiveness of clothing companies is also a major sector in logistics capability, and the average logistics cost of domestic clothing companies is 8.3 percent of sales in 2011, higher than the average 8 percent of domestic industries, and 36.4 percent of the total storage cost in 2011, higher than the 28.8 percent share of the total storage cost of domestic companies. As domestic production conditions such as wage hikes and labor disputes worsened in the 1990s, production facilities were rapidly moved overseas, which led many clothing companies to have no production facilities or a minimal production base in Korea and focus on marketing and design capabilities. The total storage capacity and storage efficiency of the logistics center became very important as the products were changed to the form of mass warehousing and small-volume forwarding. Research shows that building column spacing, a model of this research, can affect the amount of hanger rack storage empirically, so for sustainable growth of clothing companies, it is necessary to improve competitiveness in the logistics market by reducing costs and improving efficiency to overcome difficulties in corporate management. Because logistics costs are 8.3 percent and operating profit to sales ratio is 2 percent, it is expected that operating profit will increase by 41.5 percent if logistics costs are reduced by 10 percent. If 10% of storage cost is saved based on storage cost, operating profit is expected to increase by 15% To strengthen the competitiveness of the clothing industry, a reduction in logistics costs is essential. Therefore, the purpose of this study is to provide hints that logistics experts can have empirically small amounts in reducing storage costs through column spacing adjustment of logistics centers that have not been dealt with statistically until now, and to contribute to the continued growth of clothing companies and the development of the domestic logistics industry.

• Journal of Industrial Convergence
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• v.20 no.9
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• pp.25-38
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• 2022

The purpose of this paper is to verify the cost behavior of non-listed companies in Mongolia from 2013 to 2018. And we investigate the relationship between cost behavior and earnings management. Earnings management was measured using the Big-Bath and avoiding loss incentives. Big-Bath suspected firms report a very large loss and avoiding loss suspected firms have a bite profit. The results of this study are as follows. First, non-listed firms in Mongolia, operating costs(oc) and selling, general and administrative(sga) costs show the cost stickiness. Second, cost stickiness was different depending on the earnings management. The suspected avoiding loss firms have upward earnings management incentives, operating costs and sga costs all present anti-cost stickiness. The suspected big bath firms strengthen the cost stickiness of operating costs and sga costs. This study is meaningful in that it first analyzed the relationship between earnings management and cost stickiness of non-listed firms in Mongolia using empirical data. It will be meaningful in that it provides relevant information to those interested in research and investment.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.44
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• pp.179-184
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• 1997

A solution procedure to minimize total carousel related costs has been developed under the carousel throughput rate and total storage capacity requirements. The carousel related costs include carousel facility costs which are proportional to the number of carousels and carousel operating costs which are directly related to the moving distances of carousels. The number of carousels is dependent upon the size of a carousel and the moving distances are determined by the size of a carousel, storage item assignment to each carousel, and the item positions in a carousel. When the storage/retrieval requirements for each storage item is equal, an optimal algorithm has been developed. When the storage/retrieval requirements is unequal, a heuristic solution procedure has been developed because of the complexity of the problem.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.4
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• pp.328-337
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• 2004

Tool costs can comprise a significant part of the total operating costs of Flexible Manufacturing Systems. We address the problem of determining the optimal processing times of individual operations and routing mix in FMSs with multiple routes for each part type in order to minimize tool cost, subject to meeting a throughput constraint for each part type. The problem is formulated as a nonlinear program superimposed on a closed queueing network of the FMSs under consideration. Numerical examples reveal the potential of our approach for significant saving in tool costs.

• Journal of Information Technology Applications and Management
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• v.11 no.1
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• pp.69-82
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• 2004

The role of switching costs in customer retention has been posited, but has not been subjected to rigorous empirical testing. Therefore, our main focus is on the factors that influence whether consumers will have intention to switch or stay with an incumbent technology (e.g., MS-Windows). Based on consumer survey with MS-Windows users, we find empirical support for the link between the existence of compactible software, consumer's expertise in MS-Windows and intention to stay with MS-Windows. Specifically, switching costs are found to be positively associated with the existence of compatible software. Further, the lack of expertise in MS-Windows on the part of consumers tends to increase the likelihood that they will rely on current MS-Windows, rather than switch to other alternative operating systems.

• Journal of Korean Institute of Industrial Engineers
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• v.5 no.1
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• pp.67-82
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• 1979

For many capacity expansion problems, distinct capacity types must be specified to identify capacity at different locations or capacities with different costs and operating characteristics. In this study, a project-sequencing model is developed that allows operating costs to influence the timing decisions for project establishment. Under certain conditions, the power expansion formulation is derived that may be solved through the dynamic programming approach, and its first application to planning in electric power systems is selected to investigate an optimal policy and to show the impact of requiring system to service more than one type of demand. Several sample testing results indicate that in some systems the efficiency of the large nuclear plants is higher than that of smell ones that it may overcome the effects of the drop in reliability.