• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.16-18
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• 2001

Recently, a study on operation in parallel between Distributed Generation(DG) unit and power distribution system has been growing interest in power distribution system. But, introducing the DG unit causes the problem due to rising the voltage variation on power distribution system. So, This paper presents the effect of introducing DG unit on distribution system. For this simulation, KEPCO distribution system is used.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.500-508
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• 2011

In the distribution systems, the maximum power transportation capacity is restricted within 40MW based on two lines, because of the thermal current limit of a distribution line. Recently it has been continuously required to expand the abilities of the power transportation in distribution systems, as the number of large scale industrial complexes and distributed generations are growing. In this paper, we suggested the five alternatives combining two methods, laying the two bundle lines and adding another voltage between the 22.9kV and 154kV in distribution systems. This paper implemented the economic evaluations of proposed alternatives from national and customer perspectives. And then we compare the results with those of 154kV transmission system.

• Korean Journal of Plant Resources
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• v.2 no.1
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• pp.1-214
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• 1989

There shoul be high possibility of preventive and immune eficacy aqainst cancer when the anti-cancer plants are properly utilized in human dietary life as it is evident that considerable part of wild plantd or both medicinal use and ood are growing naturally in the mountainous area in korea, some of which have ben proved to be anti-cancer plants. this study, at this initial stage, has been done to acquire the fundamentals of 235 kinds of ante-cancer plants growing naturally in korea. from the results o thisresearch, the anti-cancer plants have been sorted out by amily and its number. and also the status of regional distribution of those plants and the kinds of anti-cancer plants used for both medicine and food were studied and experimented to see the medical efficacy against anti-tumor. this experiments were conduced in accodance with the total packed cell volume method and cyto toxicity method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.265-268
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• 2001

As growing the electronic commerce there are significant changes in the products/services catalog into the on-line environment. Advertent of e-catalog business opportunity for their own product/services enlarges the market volume and there are diverse methods for the presentation of its product/services. A method for the presentation of product/services features one uses identification and classification system. This study constructs a classification system and database layout for the product/services classification system as a part of e-catalog system. We consider the specific method for the GDAS-based dataset and UNSPSC classification system in the distribution industry.

• Journal of the Korean Society of Safety
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• v.8 no.2
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• pp.64-71
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• 1993

In this study, the purpose is to investigate the influence of initial residual stresses on the fatigue crack growth behaviors after the distribution of initial residual stresses Is measured when the crack is growing from the compressive residual stresses field to the tensile residual stress field. Also, the Influence of the variation of residual stress distribution on the fatigue crack growth behaviors at the crack tip is studied when the initial crack li applied on base metal, weld metal and HAZ respectively.

• Journal of the military operations research society of Korea
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• v.11 no.1
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• pp.87-110
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• 1985

This paper presents optimum policy of water supply distribution of the Osaka Prefecural Waterworks System located in the midwest of Japanese Islands. Owing to the ever increasing demand for water, the Osaka Prefectural Government endeavors to expand potable and industrial water distribution system to satisfy the growing water demand of the constituents under its jurisdiction. In this regard, the paper discusses a problem of establishing an efficient and effective water distribution system. The criteria to be considered are stability of water level at the reservoirs, stability of flow in the network, and the water treatment and distribution cost. These objective functions may be combined to form a multiple objective optimization problem or may be used independently and formulated into single objective optimization problems.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.256-257
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• 2011

The development for Eco-friendly cars has been expanded as the concern about environmental pollution and a rise in gas prices. The Electric Vehicle(EV) and Plug in Hybrid Electric Vehicle(PHEV) are generally connected on distribution power systems to charge the traction batteries. The growing number of EV/PHEVs could have a effect on distribution power systems and result in overload of power utilities and power quality problems. In order to reduce the adverse effect on distribution power systems, the influence of electric vehicle loads should be evaluated. In this paper, the influence of electric vehicle loads is evaluated by using OpenDSS(Open Source Distribution System Simulator) according to the penetration rate of electric vehicle.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2588-2590
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• 2001

Distribution ayatems at the final stage of the power supply process are directly and extensively connected to customers. There are growing demands for more efficient operation and higher reliability. This paper describes the embodiment of distribution automation using internet networks. We suggest the large region distribution server system for distribution automation functions in local area network, automated meter reading system and directed load control system with by-directional communication.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.1
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• pp.49-56
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• 1986

To obtain the information of low chlorine leaf production, the chlorine content of the soil and cured leaf in Burley tobacco growing area was investigated. The results obtained are as follows. 1. The chlorine concentration in soil at transplanting time in Kwang-ju growing area was higher than in Jeon-ju(1983), and paddy field sell showed higher concentration of chlorine than upland field in Jeon-ju(1984). The chlorine concentration in soil was different between years, locations, and cultivated land (paddy field and upland field), but the concentration, on the whole, was under the levels that might effect the leaf quality. 2. The chlorine concentration In soil was highest around todays after transplanting, and after harvesting, the concentration decreased to half of transplanting time. 3. The distribution of chlorine through the parts of tobacco plant showed remarkable difference between years, locations, cultivated land and growing stages. 4. There was significant positive correlation between chlorine concentration in top soil and chlorine content of cured leaf. 5. Chlorine content of cured leaf in Kwang-ju area(1.79%) was higher than that of Jeon-ju area(O.79%), relatively. 6. It was considered that the accumulation of salt from the sea by sea. wind did not main factor of high leaf chlorine content in seaside district.

• 한국벤처창업학회:학술대회논문집
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• 2021.04a
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• pp.33-42
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• 2021

Based on the findings of Lee et al.(2020) and Lee & Oh(2021), this paper aims to fill the gap in our knowledge regarding the relationship between strategic choices and corporate growth by utilizing a novel dataset of 'Unicorn' and 'Hyper-growing' companies. Two previous studies provide coherent findings that the relationship between firms' strategies and their performance should be explored under a more comprehensive framework with consideration of both internal and external factors. Therefore, in this study, we apply a single conceptual framework to two different datasets, which considers the strategy factors as independent variables, and the industry(market) and the firm age as moderating variables. For our dependent variables, valuations for unicorn companies and revenue CAGR for hyper-growing companies are used after categorizing them into three uniform groups. The strategy variables include 'Generic (Cost-leadership, Differentiation, focus) strategies', 'Growth(Organic, M&A) strategies', 'Leading(Pioneer, Fast-follower) strategies', 'Target market(B2B, B2C, B2G, C2C) strategies', 'Global(Global, Local) strategies', 'Digital(Online, Offline) strategies.' For industry(market) factors, it consists of historical growth rate for industries and economic, demographic, and regulatory aspects of states and countries. To overcome the differences in their units, they are also uniformly categorized into multiple groups. Before we conduct a regression analysis, we analyze the industry distribution of the 'Unicorn' and the 'Hyper-growing' companies with descriptive statistics at the integrated and individual levels. Next, we employ hierarchical regression models on Study A('Unicorn' companies in 2019) and Study B('Hyper-growing' companies in 2019) under the same comprehensive framework. We then analyze the relationship between the 'strategy' and the 'performance' factors with two different approaches: 1) an integrated regression model with both the sample of Study A and B and 2) respective regression models on Study A and B. This empirical study aims to provide a complete understanding and a reference to which strategy factors should be considered to promote firms' scale-up and growth.