• 전기학회논문지
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• 제60권6호
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• pp.1128-1133
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• 2011

In a wind farm, a large number of small wind turbine generators (WTGs) operate whilst a small number of a large generator do in a conventional power plant. To maintain high quality and reliability of electrical energy, a wind farm should have equal performance to a thermal power plant in the transient state as well as in the steady state. The wind farm shows similar performance to the conventional power plant in the steady state due to the advanced control technologies. However, it shows quite different characteristics during fault conditions in a grid, which gives significant effects on the operation of a wind farm and the power system stability. This paper presents an analysis of response of a wind farm during grid fault conditions. During fault conditions, each WTG might produce different frequency components in the voltage. The different frequency components result in the non-fundamental frequencies in the voltage and the current of a wind farm, which is called by "beats". This phenomenon requires considerable changes of control technologies of a WTG to improve the characteristics in the transient state such as a fault ride-through requirement of a wind farm. Moreover, it may cause difficulties in protection relays of a wind farm. This paper analyzes the response of a wind farm for various fault conditions using a PSCAD/EMTDC simulator.

• 한국IT서비스학회지
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• 제19권3호
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• pp.139-149
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• 2020

There are now many different commercial weather sensors suitable for smart farms, and various smart farm devices are being developed and distributed by companies participating in the government-led smart farm expansion project. However, most do not comply with standard specifications and are therefore limited to use in smart farms. This paper proposed the connecting structure of operating non-standard node devices in smart farms following standard specifications supporting smart greenhouse. This connecting structure was proposed as both a virtual node module method and a virtual node wrapper method. In addition, the SoftFarm2.0 system was experimentally operated to analyze the performance of the implementation of the two methods. SoftFarm2.0 system complies with the standard specifications and supports non-standard smart farm devices. According to the analysis results, both methods do not significantly affect performance in the operation of the smart farm. Therefore, it would be good to select and implement the method suitable for each non-standard smart farm device considering environmental constraints such as power, space, distance of communication between the gateway and the node of the smart farm, and software openness. This will greatly contribute to the spread of smart farms by maximizing deployment cost savings.

• 농촌계획
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• 제3권1호
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• pp.68-76
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• 1997

The purpose of this study is to suggest the spatial model which can be applied to the tourism farm plan. This study includes : (1) the analysis of existing facilities and activities of 22 tourism farms in Kyunggido and (2) the survey questionnaire about user's attitudes in 3 tourism farms. The results can be summarized as follows : 1) The .Major activities in the tourism farm are the resting/playing based on the natural environment and group meeting. 2) Average area is 17879.4uf (5418 坪). The most frequent facility is restaurant and lodge. 3) It is necessary to propose various types of tourism farm considering both natural conservation and development of rural region and users'various wants. The tourism farms are officially classified into four types Natural education type, Mind and body training type, Weekend farm type, Recreation type. 4) The space for tourism farm is divided into an area of production, and area of processing, and an area of convenience/recreation. 5) It is desired the convenience facilities are located in front of a farm, and the area of production is located at the back of a farm, and simple rest facilities are located all of the farm. 6) The weekend farm model and processing/convenient facility model are proposed in this study. Three types of the weekend farm models are proposed - simple type, composite type, and garden type. Three types of the processing/convenient models are proposed one building type, adjacent building type, and scattered building type.

• 대한가정학회지
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• 제28권3호
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• pp.105-125
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• 1990

The 78 housekeeping books were analyzed to find out the structure of income and expenditure of the farm household. The selected farm households were classified into 4 different farming types such as rice-cultivating, vinyl house, fruit-growing, and livestock farming. The results are summarized as follows : 1) The farm housekeeper ought to rationally manage farm household money income, because agricultural income was preponderated to several months regardless of farming types. 2) Farm household income was primarily dependent upon agricultural income and non-agricultural income in the livestock farming and rice-cultivating farm houshold respectively. 3) order of living expenses of the total farm households were recreation and entertainment expenses, food expenses, education expenses, and housing, fuel & light expenses in size. The major expenses were education expenses, food expenses and miscellaneous expenses in rice-cultivating, vinyl house and livestock farming, and fruit growing farm households respectively. 4) Balance of income and expenses of the farm household, s its time, size, and pattern of increase and decrease, was different by farming types. 5) Household expenses increased in February, May, August and December, though disposable income reversely decreased in February, April, August and December compared to each former month. So, special consideration should be taken into budget planning for household money management in February, August and December.

• 농촌지도와개발
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• 제22권3호
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• pp.261-268
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• 2015

The Strong Small Farm (SSF) is small farm, but strong farm so that the SSF competes with farm of the world. Also, SSF means that farmer brings about management innovation through improvements of continuous competence and individual efforts. Ultimate goals of SSF are to improve competence of farm household by 20 percent and to increase farm household income by 10 percent. The purpose of this paper is to examine the factors affecting the improvement of competence of the Strong Small Farm. The major findings of this study are summarized as follows. First, the results indicated that competence of farm household was improved by 8.5 percent. Second, the findings showed that management plan report, implement report, precision management consulting and whether or not he or she was urban to rural returner had a significant impact on improvement of competence.

• 한국환경과학회지
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• 제11권4호
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• pp.297-308
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• 2002

Field observations for research of oceanographic characteristics in waters adjacent to fish farm on land and water quality at area where water is supplied to fish farm and area where water is discharged from fish farm are carried out in coastal waters of Pyoson located in the southeastern region of Jeju Island in March, May, August and November of 2000. Semidiurnal tides to the northeast and southwest dominate. The mean velocities of current around neap tides and spring tides are 8.52cmㆍs$^{-1}$, 28.63cmㆍs$^{-1}$, respectively. The difference of temperature between area where water is supplied to fish farm and area where water is discharged from fish farm is about 0.6$^{\circ}C$. Seasonal variation range for temperature and salinity is 13.5$^{\circ}C$ and 3.5psu, individually. Concentrations of nitrate(NO$_3$$^{-}$), phosphate(PO$_4$$^{3-}$ ), silicate(SiO$_2$) and COD(chemical oxygen demand) are high in autumn. Particularly, concentrations of nitrate and COD in winter and spring at station where water is supplied to fish farm are higher than these at station where water is dischared from fish farm. However, concentration of phosphate and silicate at station where is supplied to fish farm in spring, summer and autumn is higher than that at station where water is dischared from fish farm. Water quality in the study area is grade 1 and this level is kept up in the whole year.

• 대한인간공학회지
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• 제28권4호
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• pp.77-82
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• 2009

This paper objected which prevented the accident occurrence of the related farm work, and developed the evaluation indicators for safety supervision on life environment of farmer and farm work to evaluate the health of farm worker and a musculoskeletal disorders. We selected the evaluation item to 82 items for executing the secondary Delphi investigation and the literature research which composed the farm work relationship specialist conference. We applied the index production of the evaluation indicators to decide the detailed element weight from the element which is farm work, the farm machine and the organization, farm workshop, dangerous substance, and life environment through the AHP techniques. Through the result, we can apply other ergonomic evaluation instrument of farm work field, but also the evaluation indicators for safety supervision on farm work.

• Journal of Biosystems Engineering
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• 제15권1호
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• pp.52-60
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• 1990

The main purpose of this report is to analyse the utilization results of farm machinery, farm mechanization rate and influences on the farm household economy. These results are summarized as follows : 1) The annual working days of major farm machinery are from 34.3 to 68.8 days for power tillers and tractors ; 7.9 to 8.5 days for rice transplanters ; 3.6 to 6.9 days for binders ; and, from 18.6 to 20.6 days for combines. Also income and expenditures of the farm management reveals al surplus in major farm machinery except for binders. 2) The popularization rate of major farm machinery is currently low, reaching the level of the early 1970's in Japan and the level of the early 1980's in Taiwan for rice transplanters and harvesters respectively. 3) The farm mechanization rate is 81.7% in plowing & levelling, 66.3% in rice transplanting, 87.5% in pest and disease control, 62.1% in harvesting and 12.5% in drying. However the farm mechanization rate of rice transplanting, harvesting and drying still remains at a low level. 4) The composition rates of farm machinery and implements are 10.2% in farm management expenditures (23.6% in Japan) and 13.2% in fixed capitals (29.4% in Japan) which still reflect a low level, and below that of the 1970's in Japan. From these analysis results, farm mechanization contributes to the improvement of farm management. Nevertheless, the popularization status and mechanization rate are still at a low level in korea. Therefore, it is deemed desirable to furthure promote effective utilization methods and guide farmers in higher safety utilization and management technology.

• 농촌계획
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• 제8권2호
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• pp.27-41
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• 2002

This research is written for offering an approach to activate the stagnated industry of the tourist farm through analysis of the current operational problems and situation on some existing tourist farm nominated as such by the authority. There will be some considerations from three different categories : local autonomous groups, tourist farm associations and farm owners. On the other hand, it is assumed that this research can also be utilized as a basic material for activating the tourist farms in the suburban area of Taegu City. The operational problems in the suburban area of Taegu City are as follows : lack of a specialized Product development, the farm operation fund, lack of operational or management ability, lack of public information, etc. There are other Problems regarding law, institution and supporting : complexity of the current system involving all kinds of permission, shortage of financial and taxation supporting, lack of training an expert manpower, lack of ability and cooperation of a deskclerk in charge, etc. Here are some suggestions taking into consideration a respective sector of local autonomous group, tourist farm associations and farm owners for activating the tourist farms in the suburban area of Taegu City. First, a mental turnabout toward a tourist farm is needed from local autonomous groups. The law and institutional base should be arranged while the financial and taxation support is materialized. Second, tourist farm associations should amend or reinforce the existing institution to refresh the current recognition toward the tourist farm through many publicity activities. On the other hand, they should develop the overall tourist farm industry into a better service industry of the rural community by keeping an active system of cooperation with other related groups. Finally, It is advised that they should conceive farms and facilities which can symbolize the tourist farm from the stage of the first construction. In addition to a four-season souvenir development, an effective publicity activity and rational investment management. Above all, they should train themselves in terms of a service spirit before they see the prosperity of the tourist farm community.

• 농촌계획
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• 제27권2호
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• pp.13-22
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• 2021

As the measures for solving problems of modern city and farming & fishing villages through mutual cooperation and complementation, this study aims to present an integrated rural area development model by changing the farming & fishing villages from a food production-focused space to a service space for the whole nation including urban residents, into the direction of creating new vitality and jobs in farming & fishing villages. In order to establish a service space that could increase the life quality and happiness of the people, this study presented the K-FARM framework types that would integrate and arrange total four themes such as rental farm, experience farm, stay farm, and management farm. In case when this K-FARM framework is applied to rural areas adjacent to cities, especially farming & fishing villages around innovative cities, there would be great effects such as expansion of exchanges between public institutions and local residents of innovative cities. Especially, the theme model classified into four types could be applied suitable for the characteristics of farming & fishing village development project district that is currently operated. Meanwhile, to realize the construction of K-FARM framework, on top of demand analysis of rental farm, it would be also necessary to additionally analyze the urban residents' demand for experience farm and management farm.