• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.55-60
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• 2014

In general, A synchronous generator is higher than the voltage stability of the induction generator. However, induction generator has many advantages rather than a synchronous generator in terms of price and maintenance. So, coverage rate of the induction generator is gradually increasing in small hydroelectric power station rather than 1000kW recently. In order to increase the penetration of induction generator, pre-analysis of the operation of the generator is needed. In this study, we analyzed for the problems that occur when synchronous generator and induction generator of 1500kW is connected to the distribution system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.300-301
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• 2015

Accurate and robust load forecasting model plays very important role in power system operation. In case of short-term electric load forecasting, its results offer standard to decide a price of electricity and also can be used shaving peak. For this reason, various models have been developed to improve accuracy of load forecasting. This paper proposes a newly forecasting model for weather sensitive season including temperature and Cooling Degree Hour(C.D.H) data as an input. This Forecasting model consists of previous electric load and preprocessed temperature, constant, parameter. It optimizes load forecasting model to fit actual load by PSO and results are compared to Holt-Winters and Artificial Neural Network. Proposing method shows better performance than comparison groups.

• Proceedings of the CALSEC Conference
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• 2001.08a
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• pp.493-501
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• 2001

B2C is not doing well in Asia and Pacific countries in comparison to U.S. and Europe. But there is misunderstanding of low growth of B2C electric commerce caused by cultural factor. Consumers in market are rational to decide their purchase according to total cost - market price and transaction cost. I examined this with data of Korea and U.S. Transaction cost in real market is less in Korea than in U.S. but that of electric commerce, it is much less in U.S. As a result, the choice of consumers in Korea is real market transaction while consumers in U.S. choose electric commerce.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.519-533
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• 2012

In this study, of currently being implemented organic cultivation in rice, the economic effects of snail agriculture, natural circulation agriculture, stevia agriculture and art nature agriculture were compared and analyzed. Analysis results showed that the economic effects of selling price per 10a, gross margin and agricultural income were increased, compared to those of previous agricultural techniques. In addition, the comparison results of economic effects by agricultural techniques showed that the agricultural income per 10a of organic cultivation were increased from the national average, compared to that of conventional cultivation. These economic effects analysis by agricultural techniques can help in the decisionmaking of farmers for the adoption of agricultural techniques in the future.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.3
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• pp.493-501
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• 1996

An understanding of consumers' evaluative processes and the consumer variables that influence cross-cultural evaluations of foreign products is essential to effectively penetrate international markets. This study compared consumers in two developing countries, Korea and Mexico, regarding their product evaluations and purchase intentions for US Levi's jeans. Both Korean and Mexican consumers are generally quality and price conscious. Korean consumers appeared to be more value-conscious than Mexican consumers. Mexican consumers exhibited high level of brand and prestige conscious behavior. Findings in this study support that culture bound consumer characteristics vary from country to country resulting in differences in perception of quality, value and purchase intentions for a particular product. The perception of product quality differs from perception of value and subsequent willingness to buy. For a comprehensive understanding of consumer purchase behavior, the impact of value-conscious attitude on percetion of quality and on purchase intentions should be examined.

• Journal of Communications and Networks
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• v.14 no.6
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• pp.672-681
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• 2012

A potential breakthrough of the electrification of the vehicle fleet will incur a steep rise in the load on the electrical power grid. To avoid huge grid investments, coordinated charging of those vehicles is a must. In this paper, we assess algorithms to schedule charging of plug-in (hybrid) electric vehicles as to minimize the additional peak load they might cause. We first introduce two approaches, one based on a classical optimization approach using quadratic programming, and a second one, market based coordination, which is a multi-agent system that uses bidding on a virtual market to reach an equilibrium price that matches demand and supply. We benchmark these two methods against each other, as well as to a baseline scenario of uncontrolled charging. Our simulation results covering a residential area with 63 households show that controlled charging reduces peak load, load variability, and deviations from the nominal grid voltage.

• KDI Journal of Economic Policy
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• v.40 no.3
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• pp.45-68
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• 2018

We uncover a nexus between actual inflation, inflation perceptions and expectations in Korea through analyzing micro as well as aggregate data from the Consumer Survey. We document two novel findings. First, households' subjective perceptions of inflation exert more impact on expectation formation than actual inflation. Second, inflation perceptions are broadly in line with the trajectory of the inflation trend. This is attributable to the fact that changes in actual inflation have been generated mainly by the consumption items whose price changes are perceived more sensitively as those items are frequently bought or have a larger share in household expenditures. Conducting a cross-country comparison, we find that information rigidity in expectation formation process and the nexus between perceptions and expectations of inflation prove to be stronger in Korea. Additionally, we reconfirm the existing finding that the scope of information utilized for forming inflation expectations is fairly circumscribed.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.330-332
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• 2001

This paper reviews technology for power quality differentiated supply in power system. Since price and power quality has been single goods in the light of customer-side view point but hereafter it is essential for power market to introduce multiple goods which is composed of differentiated combination between them. This paper should like to work out strategy for power quality differentiated supply in domestic power system by comparison characteristics of differentiated background and its relevant various theory.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.470-474
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• 2010

Various anti-scattering agents for suppression of dust scattering at waste depository were compared in this study. Based on the price, easy of usage, and no toxicity, 1% of $Al_2(SO_4)_3$ was selected as surface hardening agents. Only lower than 2% of total weight were flied when wind speed was monthly maximum velocity during 1 hr. These results were quite good with comparison of S anti-scattering agents which was made by C company in Korea. When $Al_2(SO_4)_3$ was spread, the surface waste became hard therefore the effect of suppression of scattering dust was long lasting. It was recommend that 2% of $Al_2(SO_4)_3$ was spread to keep suppression of scattering dust when sudden gust of wind such as natural disaster was occurred.

• Journal of Information Processing Systems
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• v.15 no.6
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• pp.1335-1349
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• 2019

Crowdsensing technologies can improve the efficiency of smart parking system in comparison with present sensor based smart parking system because of low install price and no restriction caused by sensor installation. A lot of sensing data is necessary to predict parking lot saturation in real-time. However in real world, it is hard to reach the required number of sensing data. In this paper, we model a saturation predication combining a time-based prediction model and a sensing data-based prediction model. The time-based model predicts saturation in aspects of parking lot location and time. The sensing data-based model predicts the degree of saturation of the parking lot with high accuracy based on the degree of saturation predicted from the first model, the saturation information in the sensing data, and the number of parking spaces in the sensing data. We perform prediction model learning with real sensing data gathered from a specific parking lot. We also evaluate the performance of the predictive model and show its efficiency and feasibility.