• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.44-55
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• 2010

The proposed offshore wind farm projects, i.e., Mooudo offshore, Yeonggwang-Gochang offshore, Saemangeum offshore, Imjado offshore and Gadeokdo-Dadeapo offshore, were compared and analyzed using the Korea National Wind Mapand Wind Farm Suitability Assessment System developed by the Korea Institute of Energy Research. The suitability of the proposed areas was comprehensively assessed using geographic, economic constraints, wave condition and wind resource factors, but the focus of this paper was on the geographic constraints and wave conditions. Imjado had several geographical constraints, despite having a good wind power density, while Saemangeum had a relatively low wave height, shallow water depth, close substation and slow tidal current. It is anticipating that the present comparison and analysis could be used as reference guidelines when selecting and preparing the design of large-scale offshore wind farm in the near future.

• Journal of Electrical Engineering and Technology
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• v.7 no.6
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• pp.869-875
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• 2012

Because of the nature of wind, the output power of wind turbines fluctuates according to wind speed variation. Therefore, many countries have set up wind-turbine interconnection standards usually named as Grid-Code to regulate the output power of wind farms to improve power system reliability and power quality. This paper proposes three operation modes of wind farms such as maximum power point tracking (MPPT) mode, single wind turbine control mode and wind farm control mode to control the output power of wind turbines as well as overall wind farms. This paper also proposes an operation scheme of wind farm to alleviate power fluctuation of wind farm by choosing the appropriate control mode and coordinating multiple wind turbines in consideration of grid conditions. The performance of the proposed scheme is verified via simulation studies in PSCAD/EMTDC with doubly-fed induction generator (DFIG) based wind turbine models.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.2
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• pp.247-252
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• 2016

The latest offshore wind turbines are easily exposed to lightning strikes because they are designed with longer blades and taller height to satisfy the growing capacity demands. The generation facilities and elements of the offshore wind farm are more vulnerable to lightning damage because of more severe, unpredictable weather conditions. Therefore, this paper presents the analysis of measure for lightning overvoltage mitigation in offshore wind farm planned in South Korea southwest seashore. The sensitivity analysis includes the steady state and transient state characteristics of offshore wind farm and proposes the countermeasure for mitigation of transient overvoltage by considering earth resistivity of the offshore environment.

• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.16-21
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• 2013

In this paper, the mooring system for a floating wave energy farm is designed based on a two-dimensional analysis. The mooring system uses an anchorless mooring line linking two floaters in a floating wave energy farm. The basic equation to determine the length of the mooring line between the two floaters is proposed. The other properties such as the diameter and pretension are taken from the mooring line for a single floater. The dynamic behavior and safety of the designed mooring system under extreme ocean conditions are analyzed with the commercial software Orcaflex. A numerical study shows the stability and high safety in tension of the designed mooring lines for a floating wave energy farm. The proposed anchorless mooring system for a floating wave energy farm results in a considerable reduction in the length of the mooring line, contributing to the economics of a floating wave energy farm.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.487-490
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• 2002

Wind farm paralleled with electric power network can supply the power into a power network not only the normal conditions, but also the fault conditions of distribution network. If the fault happened in the power line with wind farm, the fault current level measured in a relaying point might be lower than that of distribution network without wind turbine generator. Consequently, it is difficult to detect the fault happened in the distribution network connected with wind generator. This paper describes the influence of wind turbine generator on the protective relaying system for detecting the fault occurred in a power line network. Simulation results shows that the fault current depends on the fault impedance, location, and the capacity of wind farm and distribution network load.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.65-75
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• 1990

This study is purposed to examine how fanner's living conditions and managements have been improved during the last five years(1985 through 1989) on the basis of the information got from the sample survey of 30 farm households chosen in Galma-ri, Buseok-Myeon, Seosan county, Chungnam province. The followings are major results of the study. (1) There have been much improvement of kitchen facilities and increasing number of cultural goods, but not much in the condition of sanitation facilities. (2) The size of farm warehouse and stall have been greatly enlarged and there has been large variation in the heads of big animals such as cattle during the surveyed period. This may reflect the facts that farm managements become more diversified and commercialized. (3) It is shown that fanners more voluntarily accept new fanning techniques about their concerning crops. Also there have been rapid changes in the pattern of upland cropping system, adjusting to the commercialization of agriculture. (4) Currently, fanners tend to react to the price signal of market system more sensitively than before. Accordingly, agricultural income structure is varied subject to price fluctuation in the short run period.

• Journal of Fisheries and Marine Sciences Education
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• v.24 no.2
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• pp.224-233
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• 2012

Hazard Analysis and Critical Control Points (HACCP) is a systematic preventative approach for food safety and is generally used in food industry to identify potential food safety hazards. Recently, the Korean Ministry for Food, Agriculture, Forestry and Fisheries planed to applicate HACCP programs as an effective approach to food safety and protecting public health at the aquaculture farm of rainbow trout, Oncorhynchus mykiss. For the purpose, it need to identify what kinds of hazards are in the aquaculture farm. In the present study, we established Sanitation Standard Operating Procedures (SSOP), which addresses sanitation conditions and practices in the aquaculture farm. SSOP is essential prerequisite programs of HACCP to reduce or eliminate the risk of the hazards being realized. We anticipate that the HACCP programs of aquaculture farm will contribute to supply foods in safety to consumers.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.3
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• pp.53-60
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• 2014

The purpose of this paper is to seek the dwelling conditions for comfortable life like urban apartment with agriculture in farming area. In order to do above things, we divide types of people who is planning to 'return farm' and need to heavily research and analyze current status of use for farm house's each spaces include outside spaces. so this paper aimed that at first, divide types of farmhouse following agriculture condition for people who is living in rural and survey the present condition and problems by analyzing of present status of space use and draw the improvement plans for those. after then, finally make a architectural basic data for Rural houses plan. For the future, the main purpose of this paper is that make architectural provision possible by researching types and size of storage following sort and size of farm.

• Journal of the Korean housing association
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• v.13 no.2
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• pp.31-38
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• 2002

The purpose of this study is to investigate the architectural change of the modern Korean farm-houses. Regional boundary of this study is confined to Pocheon-Gun, and the object is mainly forty-two farm-houses as long as sixty years since it was built. An analysis is made on the change of spaces, facilities and finished materials of farm-houses. The results of this study, An-Chae have changed for the more comfortable living conditions through the spatial changes as like the fittest facilities with spatial extension and integration. And in Arae-Chae, unlike An-Chae, the old and unused space often have transformed to the other function and the its facilities remained still unimproved.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.449-454
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• 2017

Recently, increasing attention has been paid to the welfare of farm animals, which have been evaluated using behavioral and physiological measures. However, so far, the measures have almost always been used to estimate poor welfare. In this review, firstly we focus on how oxytocin (OT) relates to positive social behavior, pleasure, and stress tolerance, and second on which management factors stimulate OT release. OT induces maternal and affiliative behaviors and has an anti-stress effect. Further, OT is produced during enjoyable events, and has positive feedback on its own release as well. Therefore, to some extent, the relationship of OT to positive normal behavior was mutually beneficial-heightened OT concentration owing to comfortable rearing conditions induces positive social behavior, which in turn may increase OT concentration. Hence, studies on animal welfare should pay more attention to increasing comfort and the stress tolerance, rather than only focusing on when stress occurs in farm animals.