• Solar Energy
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• v.18 no.2
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• pp.51-67
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• 1998

In this paper, various solar systems are introduced according to usage pattern considering national weather condition and hot water comsumption pattern. First, basic principle and components of solar hot heater are presented, and then operational machanism of various solar hot water systems are presented according to the case of domestic and industrial use with network of piping.

• Journal of Distribution Science
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• v.13 no.6
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• pp.17-23
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• 2015

Purpose - Transnational corporations (TNCs) have influenced drastic changes (financial services, manufacturing, labor, technology transfer) in Central Eastern Europe (CEE). This paper examines the indirect changes in the CEE pattern of industrial development and market distribution. Research design, data, and methodology - Over 25 years, neighboring (or rival) countries competed to attract TNCs as a double-edged strategy for privatization and debt reduction. Through their experience attracting foreign direct investment (FDI), many countries started to reflect aspects of national capitalism. Countries also began to realize in 2010 that TNCs sought to enter markets with more favorable conditions for export-oriented manufacturing. Results - The analysis reveals that TNC investment strategies were aimed at eliminating local competition to acquire industrial "brown fields" to convert into "green fields." CEE countries have since strengthened their national systems and the support of large-scale state-owned enterprises and small and medium-sized start-up enterprises. Conclusions - CEE has changed based on industrial development and a regional structure of TNC market distribution and associated government policies. The pattern toward flexible markets gives countries the ability to further their economies.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.4
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• pp.80-86
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• 1996

In order to decrease fuel comsumption rate and emissions, lean burn engine which has equipped swirl control valve, is investigated experimentally on the test bench. Single cylinder engine was used to test the combustion and emission performance with 4 kinds of swirl valve. Decrease in the carbon monoxide, hyerocarbon and specific fuel consumption was shown at the lean condition, which means that a good choice of swirl valve on the given intake port geometry can be used to increase the combustion efficiency and lean limit.

• Analytical Science and Technology
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• v.8 no.4
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• pp.835-841
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• 1995

The quantitation of inorganic anions in various drinking waters were investigated using capillary electrophoresis(CE) and the results were compared with ion chromatography(IC). With CE, in contrast to IC, was demonstrated rapid analysis, good efficiency, a low detection limit and the low comsumption of a solvent and samples. CE analysis was used 5 mM sodium chromate(pH 8.0) containing 20 mM tetraalkylammoniumbromide at -25kV applied voltage with indirect UV detection at 254 nm. This results in exceedingly short analysis time within 3 min. with efficiencies approaching 200,000 theoretical plates. The coefficients of variants of migration time are less than 0.8% and those of peak area are less than 2.3%. Detection limits for quantitative determination were 300 ppb-50 ppm level. These optimum conditions are applicable to various samples without pretreatment.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1286-1288
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• 1994

Methods are described for the design and fabrication of the sensor circuits on the polarographic oxygen sensing electrodes. The discussion includes: a method for the +5V single-supply driving for the sensor circuits, a method of low power comsumption for the front-end electronics. Typical polarograms for the commercial DO probes using this sensor circuits are presented. High accuracy of the I to V conversion using the circuits is verified.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.3-4
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• 2007

Wireless Sensor Network is a form of network which consumes relatively less data trasmisson rate and energy. In this type of network, minimizing the consumption of energy so that it maximizes life time is very important. To be able to improve the energy comsumption, we propose the mechnism to trasmit broadcasted packet according to level value with priority assiagned to each relay node.

• Korean Journal of Microbiology
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• v.20 no.2
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• pp.67-72
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• 1982

The effect of fermentation temperature on the production of high content alcohol has been investigated with high substrate concentration. The maximum specific growth rate, ${\mu}max\;was\;0.461hr^{-1}\;at\;35^{\circ}C$ which was the highest, whereas the maximum biomass concentration waas 8.7g/l at $25^{\circ}C$, at the growth rate lower than at $35^{\circ}C$. Approximately 140g/l of ethanol was produced in the temperature range of 20 to $25^{\circ}C$ with nearly complete comsumption of the substrate. Extended fermentation time has been required at lower temperatures, however, for the maximum values of biomass concentration and alcohol content, hence higher ethanol productivity, as the temperature was elevated to $40^{\circ}C$. The viability of yeasts was greatly improved by lowering the fermentation temperature down to $25^{\circ}C$ and also extended survival of the cells has been observed at lower fermentation temperatures, although the ethanol concentration of both waas higher.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1088-1090
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• 1993

This paper shows efficient peak demand control method in office buildings. With a rapid growth of national economics and living standard, electrical energy consumption markedly increased. Expecially, it is increased electrical energy comsumption in the office buildings and thus an energy conservation through efficient use of electricity became more important. From the data of electric equipment capacity and electric power consumption for 96 buildings, current levels of demand factor and a growth trend of peak loads by office buildings were surveyed and analyzed. In addition the efficient peak demand control method in office buildings were studied.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.804-811
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• 1997

In the CDMA mobile communication system, reverse power control can be used to minimize the interference level for a good quality of the voice channel, and used to maxmize the system capacity. In this paper, we have analyed the environment of the K-parameter and the access procedure for the mobile station, and proposed a new algorithm for the access probe procedure of the station. K-parameter is determined according to the environment of the base station and access probe can adaptively control the power according to the position changes of the mobile station or the rapid and various state changes of the channel. Simulation results in the limited test environment show that it can increase the system capacity and decrease the power comsumption of the mobile station while maintaining the good and stable quality of the voice channel.

• Journal of Forest and Environmental Science
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• v.9 no.1
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• pp.19-32
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• 1993

Domestic timber comsumption has increased dramatically in the past few decades in this country. In addition, there is increasing demand for recreational opportunities in the forest areas and concern for watershed management and soil conservation. However, it is difficult to satisfy these demands for forest resources because many of woodland owerners who make such demands possible move from mountain villages to modern cities. Therefore, whether or not it is in the public interest to invest in rurbanization is a central policy question. This is a case study which deals with mountain village problems for making forest resources.