• Journal of Institute of Control, Robotics and Systems
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• v.16 no.3
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• pp.305-312
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• 2010

The aim of this study is to find an analytic solution to the problem of determining the optimal capacity of a batch-storage network to meet demand for finished products in a system undergoing joint random variations of operating time and batch material loss. The superstructure of the plant considered here consists of a network of serially and/or parallel interlinked batch processes and storage units. The production processes transform a set of feedstock materials into another set of products with constant conversion factors. The final product demand flow is susceptible to joint random variations in the cycle time and batch size. The production processes have also joint random variations in cycle time and product quantity. The spoiled materials are treated through regeneration or waste disposal processes. The objective function of the optimization is minimizing the total cost, which is composed of setup and inventory holding costs as well as the capital costs of constructing processes and storage units. A novel production and inventory analysis the PSW (Periodic Square Wave) model, provides a judicious graphical method to find the upper and lower bounds of random flows. The advantage of this model is that it provides a set of simple analytic solutions while also maintaining a realistic description of the random material flows between processes and storage units; as a consequence of these analytic solutions, the computation burden is significantly reduced. The proposed method has the potential to rapidly provide very useful data on which to base investment decisions during the early plant design stage. It should be of particular use when these decisions must be made in a highly uncertain business environment.

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.41-49
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• 2015

The amount of energy consumed in air ventilation systems of public facilities accounts for 40% of their total energy consumption. To reduce their energy consumption, applying variable speed operation controlled by an inverter with a high-efficiency motor is suggested. Since these methods require higher initial investment costs compared to the existing systems, economic evaluation should be conducted from a long-term perspective. While LCCA(Life Cycle Cost Analysis) model is useful to estimate net savings of alternatives that differs with respect to initial costs and operating costs, the environmental burdens are not considered. On the contrary LCA(Life Cycle Assesment) model is suitable to assess environmental impacts associated with the stages of a product's life but it does not consider costs. In this study, the high-efficient motors are introduced into the air ventilation system of a subway station and a comprehensive analysis on the economic and environmental impacts of the proposed method is conducted by using LCCA and LCA model.

• Management & Information Systems Review
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• v.36 no.4
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• pp.53-80
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• 2017

The purpose of this study is to examine the determinants of the number of bank relationships in Korea. Firm-specific determinants considered here include leverage, size, age, return on asset, investment grade, tangibility, liquidity, R&D expenditure. We estimate the effects of these variables, and compare the results with those from previous studies performed for other economies. Concerning the effects of business cycle, we find that the business cycle is an important factor in determining the number of bank relationships. The number of bank relationships varies over the business cycle, and we notice a counter-cyclical behavior, which means the number decreases during economic expansions and increases during contractions. This result can be interpreted as a result of firms' diversification of borrowings into multiple banks in order to reduce the liquidity risk during the recession. In the subsets, however, the number of bank relationships for large firms is stable regardless of the business cycle. Unlisted firms, non-chaebol, and low credit quality firms which have relatively limited access to alternative sources of financing show counter-cyclical behavior. Finally, such phenomena is not observed in the non-competitive credit market, while they show a counter-cyclical behavior in the competitive credit market.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.1 no.2
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• pp.157-192
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• 2006

Since the late 1990s, the Korean Venture Capital Industry has been remarkably grown in the aspect of quality and quantity. Korean government expects that the Venture company and Venture Capital Industry would contribute to the recovery of depressed Korean economy and restructuring of the high cost and low efficiency economic structure. Korean government reinforces supporting policies for the Venture Capital and Venture Business. Venture Capital is defined as the form of high risk and high profit investment capital growing the small & medium enterprises to competitive ones through capital and management support and collecting the capital. According to the Gompers and Lerners the venture capital cycle consists of raising investment capital, screening the investment opportunity and invest the money. And later, sold the retained stock to the other investor or to the company. This stage called EXIT Consequently, the function of the venture capital, which supply the fund and the business consultation to venture business, have been emphasized and how to effectively run this capital have been recognized as the way to develop the venture business. In this regard, the problem in Korean Venture Capital Market is as follows. First, most of the sources of fund depends on the government support and this conflict with the nature of risk capital because the government capital emphasis the stability than profitability. And secondly, the efficiency of the venture capital system in Korea do not reach that of the advanced countries due to many kinds of restriction and the rack of support. Consequently, the Activation Schemes for Korean Venture Capital Firms are as follows. First, the sources of venture capital need to diversify from angels to institutional investors such as banks, pensions, fund of fund. And Lastly, the internal management and operational system of venture capital companies should be strengthened by quality to that of global Venture Capital Firms.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.97-110
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• 2020

This paper is on the policy proposal for venture ecosystem. First, one of the three secrets of the US venture ecosystem is the law of 50:50. Angel capital investment is as important as venture capital investment. Although professional angel investors and accelerators account for as much as VC in the venture ecosystem, they are ignored from policy considerations. We argue that the revision of related law is urgent. Second, large US firms invest more in M&As than in internal R&D. Therefore, accelerators and professional angel investors could make effective investment recovery after investing in a startup company. In other words, angel capital does not come in without secondary market development. Angel capital and secondary markets are the two pillars of the venture ecosystem. The government alone is difficult to develop a secondary market. This is why the private sector should come in and introduce corporate venture capital (CVC). Third, we believe the policy direction for national economic growth should be extended from the startup to scale-up. This is because the startup's sales and job creation will start in five years. While the previous study focused on funding (venture financing), this paper aims to balance all three stages of a venture: startup, growth, and recovery, which are the life cycle of a venture company or venture investment. In particular, we propose specific policies in each chapter to improve practical application.

• Journal of the Korean Institute of Educational Facilities
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• v.14 no.4
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• pp.34-42
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• 2007

The investment of BTL(Build-Transfer-Lease) projects for the educational facilities has been increased since 2005. However, many trial errors and problems have been occurring due to the lack of inspection criteria in maintenance cost for the lift cycle of the facilities. Thus, purpose of this study is to derive regression equation for the daily inspection and the regular inspection through analysis of CAD data in order to set the inspection criteria. It is possible to calculate economical maintenance cost of BTL project in educational facilities using criteria of inspection time through the regression equation developed in this study.

• Journal of Information Technology Services
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• v.14 no.1
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• pp.41-51
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• 2015

The purpose of this research is to investigate the relationship between job creation and ICT usage in service industries. This research is particularly important because job creation is one of the most critical issues for the country. With technology innovation and system integration, manufacturing industries do not create enough employment, therefore, the society relies on service industries for creating job opportunities. Until now, due to limitations, analysis of job creation in service industries through ICT usage has not been investigated in depth. Thus, development of an effective ICT support policy was impossible. In this research, we used seven methods to investigate overall relationship between ICT usage level and job creation. A rule of large numbers has been applied to reach conclusion. Through this research, the government can focus its investment on service industries where job creation rate is the highest. We can expect both reinforcement in competitiveness of our service industry and continuous creation in employment, eventually leading to a virtuous cycle.

• Korean Journal of Computational Design and Engineering
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• v.18 no.4
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• pp.299-307
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• 2013

Introduction of PLM in domestic shipyards is being retarded as ship PLM has yet to firm up return of investment and process integration. To implement a ship PLM system, it is required to share ship CAD model data in various design and manufacturing environments. Lightweight CAD models provide a promising solution for sharing CAD models in the product life cycle, which can expedite implementation of ship PLM in domestic shipyards in the near future. Compared to proprietary CAD models, it is easy for lightweight CAD models to be interfaced with various application systems and be connected to manufacturing information. In this paper, the reason why lightweight CAD models are necessary to implement a ship PLM system is addressed and current implementation results are introduced.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.3
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• pp.299-308
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• 2009

In this paper, we have developed an evaluation model of technology green index(TGI) which includes 3 evaluation factors and 13 indicators. Furthermore, as presenting the degree of relative importance among evaluation factors and indicators for all R&D evaluation stages and all green technology areas, and applying the proposed model to 5 defense projects, we have found applicability of the model to evaluation of defense R&D projects. The results of evaluation using this model can be used to monitor the performance of project life cycle and develop R&D investment strategy of green technology using portfolio analysis.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.722-729
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• 2007

The methodology for maintenance system development should overall be considered with all of task characteristic, schedule, and the technical condition of investment sources. This research applies Waterfall model to methodology for the development and construction of maintenance system through customizing the CD (Custom Development) procedure of "HSDM (Hyundai System Development Methodology)" based on information engineering. The waterfall model called as classic life cycle paradigm is defined for the sequent development procedure, which make progress a next step after that a previous step is admitted with thorough review. This model which is popular and the oldest paradigm is used for system development by four steps; demands analysis, design, construction, and maintenance. This methodology advances higher abstract step from higher lower step using top-down approach from concept definition to construction, which notices the end of a step whenever a step is over. Therefore, each step is exactly divided, and consequently the output is clearly yielded.