• 수산경영론집
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• 제48권3호
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• pp.47-59
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• 2017

Fish mortality is the most important success factor in aquaculture management. To order fingerlings considering the effect of mortality is a important problem in aquaculture farm. This study is aimed to decision the number and size of fry in aquaculture farm. This study build the mathematical model that finds the value of decision variable to minimize total cost that sums up the fingerling purchasing cost, aquaculture farm operating cost and feeding cost under mortality constraint. The proposed mathematical model involve biological and economical variables: (1) number of fingerlings (2) fish growth rate (3) mortality (4) price of a fry (5) feeding cost, and (6) possible order period. Numerical simulation model presented here in. The objective of numerical simulation is to provide for decision makers to analyse and comprehend the proposed model. When extensive biological and cost data become available, the proposed model can be widely applied to yield more accurate results.

• 한국대기환경학회지
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• 제19권6호
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• pp.745-756
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• 2003

An analysis of wind environments using computational fluid dynamics and an evaluation of wind resources using measurement data obtained from meteorological observation sites at Homi-Cape, Pohang have been carrid out for siting a wind farm. It was shown that a numerical simulation using computational fluid dynamics would provide reliable wind resource map in complex terrain with land-sea breeze condition. As a result of this investigation, Homi-Cape wind farm with 11.25 ㎿ capacity has been designed for maximum power generation and 25.7 GWh electricity production is predicted.

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.145-152
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• 2021

Environmental change due to construction of large offshore wind farm has been a debate for a long time in Korea. There are various data acquired on hydrodynamics around this area before and during construction of offshore wind farm but no data during operation could be made due to delayed schedule. In this study, environmental change such as bathymetry change and scouring was forecasted using MIKE, numerical hydrodynamics model, and its results were validated using the observation data before and during construction.

• 현장농수산연구지
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• 제26권2호
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• pp.14-24
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• 2024

To enhance the usability of smart agriculture, methods for utilizing smart farm data are required. Therefore, this study proposes a scheme for utilizing regional smart farm data by linking it to services. The current status of domestic and foreign smart farm data collection and linkage services is analyzed. To collect and link regional smart farm data, necessary data collection, data cleaning, data storage structure and schema, and data storage and linkage systems are proposed. Based on the standards currently being implemented for regional smart farm internal data storage, a farm schema, environmental information schema, facility control information schema, and growth information schema are designed by extending the crop schema and crop main environmental factor information database schema. A data collection and management system structure based on the Hadoop Ecosystem is designed for data collection and management at regional smart farm data centers. Strategies are proposed for utilizing regional smart farm data to provide smart farm productivity improvement and revenue optimization services, image-based crop analysis services, and virtual reality-based smart farm simulation services.

• 한국전자통신학회논문지
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• 제15권5호
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• pp.939-948
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• 2020

가상현실 기술을 농업 기술 교육에 접목하려는 많은 노력이 이루어지고 있으며, 농기계 교육과 같은 직접적인 교육뿐만 아니라 게임을 이용한 간접 교육에도 관심이 증가하고 있다. 가상현실에서 핵심적인 기술은 사용자가 실제와 같이 느낄 수 있게 대상을 모델링하는 것이다. 농장에서 재배하는 농작물은 농장의 환경에 따라 동일한 영향을 받는다. 또한, 농작물은 각각 독립적인 특성도 가지게 된다. 본 논문에서는 농작물 모델링의 이러한 특성을 반영하여 NPC 형태로 모델링하는 방법을 제안한다. 제안하는 방법에서는 개별 농작물이 날씨와 농장의 특성을 반영하는 방법과 독립적인 특성을 반영하는 방법을 구현한다. 구현 결과는 제안하는 방법이 간단한 알고리즘을 사용하지만 농작물을 매우 사실적으로 표현하는 것을 보여준다.

• 수산경영론집
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• 제51권2호
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• pp.1-13
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• 2020

The purpose of this study is to analyze consumer preference for fish farm HACCP certification using conjoint analysis. This study used raw flatfish product to evaluate the fish farm HACCP. In this study, 500 consumers were surveyed using panel survey and stratified sampling. In the recognition analysis, the farm HACCP certification system was found to be highly recognized by consumers. It can be seen that the brand assets accumulated by existing food and agricultural HACCP certification were transfered to the fish farm HACCP and absorbed. Consumers perceived fish farm HACCP certification as similar one with existing food and agricultural HACCP. Conjoint analysis evaluated three levels factors. The attributes and levels evaluated were : price(25,800 won, 28,400 won, 31,000 won), certification(fish farm HACCP, seafood traceability, and non certified), and origin(domestic, JEJU, and WANDO). The important levels were in order of price(40.8%), certification(30.2%) and origin(29.0%). We found that consumers give higher utility to fish farm HACCP certification compared with non certified and seafood traceability certification. Market simulation results showed that the fish farm HACCP product has 12%p higher market share than non certified products. Seafood traceability certification showed 4.6%p higher market share than non certified products.

• 제어로봇시스템학회논문지
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• 제19권1호
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• pp.34-39
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• 2013

This paper proposes the implementation of robust fuzzy controller for designing intelligent wind farm and mitiagating the fluctuation of wind power generator. The existing researches are limited to individual wind turbine with variable speed so that it is necessary to study the multi-agent wind turbine power system. The scopes of these studies include from the arrangements of each power turbine to the control algorithms for the wind farm. For solving these problems, we introduce the composition of intelligent wind farm and use the T-S (Takagi-Sugeno) fuzzy model which is suitable for designing fuzzy controller. The control object in wind farm enables the minimizing the fluctuation of wind power generator. Simulation results for wind fram which is modelled as mathematically are demonstrated to visualize the feasibility of the proposed method.

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.151-157
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• 2003

Wind farm interconnected with grid 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 distribution power line with wind fm, the fault current level measured in a relaying point might be lower than that of distribution network without wind turbine generator due to the contribution of wind farm. Consequently, it may be difficult to detect the fault happened in the distribution network connected with wind generator This paper describes the effect of the interconnected wind turbine generators on protective relaying of distribution power lines and detection of the fault occurred in a power line network. Simulation results shows that the current level of fault happened in the power line with wind farm depends on the fault impedance, the fault location. the output of wind farm. and the load condition of distribution network.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.334-336
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• 2003

This paper describes the influences of the large scaled wind farm interconnected with 154 kV power networks on the operational characteristics of distance relay applied in the transmission line. The wind farm composed of wind turbine generators are one of the great energy sources: they can supply the power into an interconnected network not only the normal conditions, but also the fault conditions of power network. Therefore, the distance relay applied in the transmission tine may mal-operate due to the contribution of wind farm. This paper presents the operational characteristics of distance relay for the fault occurred in the transmission line interconnected with wind farm. Simulation results show that it is difficult to recognize the fault location due to the power output of wind farm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.247-248
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• 2015

Wind turbines causes instabilities on the grid as their penetration increase. To mitigate harmful effects from wind turbines, transmission system operator(TSO) set up some requirements to obligate for wind generation operator for grid connection. So wind farm management system(WFMS) has important role to follow requirement from TSO, WFMS calculates available real power by considering wake effects, and dispatches real power order to each wind turbine in wind farm to optimize for decreasing load fatigue. To verify operation of WFMS, real-time simulator(RTS) is necessary. This paper deals with RTS configuration to verify WFMS operation. RTS includes wind farm model and power flow code. Normally, wind farm equivalent simple model makes wind turbines in wind farm to one wind turbine mode which cannot verify power flow in wind farm and WFMS operation. Thus, this paper makes wind farm model using simple wind turbine model with transfer function. Matlab is used for make power flow code and wind farm model to impose RTS and those model is certified by PSCAD/EMTDC.