• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.1
• /
• pp.130-133
• /
• 2020

Smart pig farm which is based on IoT has been widely adopted by many pig farmers. In order to achieve optimal control of smart pig farm, the relation between environmental conditions and performance metric should be characterized. In this study, the relation between multiple environmental conditions including temperature, humidity and various performance metrics, which are daily gain, feed intake, and MSY, is analyzed based on data obtained from 55 real pig farm. Especially, based on preprocessing of data, various regression based machine learning algorithms are considered. Through performance evaluation, we show that the performance can be predicted with high precision, which can improve the efficiency of management.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.1
• /
• pp.57-71
• /
• 2009

Crop-livestock mixed farming systems depend on the efficiency with which nutrients are conserved and recycled. Home-grown forage is used as animal feed and animal excretions are applied to cultivated crop lands as manure. The objective of this study was to develop a mixed farming system model for dairy cattle in Japan. The model consisted of four sub-models: the nutrient requirement model, based on the Japanese Feeding Standards to determine requirements for energy, crude protein, dry matter intake, calcium, phosphorus and vitamin A; the optimum diet formulation model for determining the optimum diets that satisfy nutrient requirements at lowest cost, using linear programming; the herd dynamic model to calculate the numbers of cows in each reproductive cycle; and the whole farm optimization model to evaluate whole farm management from economic and environmental viewpoints and to optimize strategies for the target farm or system. To examine the model' validity, its predictions were compared against best practices for dairy farm management. Sensitivity analyses indicated that higher yielding cows lead to better economic results but higher emvironmental load in dairy cattle systems integrated with forage crop production.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.3
• /
• pp.231-241
• /
• 2017

The purpose of this study was to analyze traffic safety assessments for fishing vessels near the southwest offshore wind farm. This study applied a collision model for safety assessment. It also involved a spatiotemporal analysis of vessels engaged in fishing to identify fishing hotspots around the offshore wind farm. This study used data from fishing vessel location transmission devices gathered over 1 year in 2014. As a result, in September, when the average number of vessels engaged in fishing is high, 62 ships were operating in fishing section 184-6 and 55 ships in section 184-6. In addition, in fishing sections 184-8 and 192-2, where an offshore wind farm was located, there were 55 and 38 ships operating, respectively. As the recovery period for a seaway near wind farm turbines is 55 years, it was determined that safety measures are required in order to reduce collision frequency while allowing fishing vessels to navigate through offshore wind farms. Meanwhile, the return period of Seaway B between the groups of generators considered was 184 years. A safety zone for offshore wind farms should be installed covering a distance of at least 0.3 NM from the boundary of turbines. Then, the collision return period was derived to be close to 100 years. Through this traffic safety assessment, it has been concluded that such measures would help prevent marine accidents.

• Journal of Advanced Marine Engineering and Technology
• /
• v.35 no.8
• /
• pp.1063-1069
• /
• 2011

This paper presents aerodynamic power outputs of wind turbine of 6 MW wind farm composed of 3 sets of 2 MW wind turbine according to the separation distance by using CFD. Layout design including offshore wind farm and onshore wind farm is key factor for the initial investment cost, annual energy production and maintenance cost. For each wind turbine rotor, not actuator disc model with momentum source but full 3-dimensional model is used for CFD and it has a great technical meaning. The results of this study can be applied to the offshore wind farm layout design effectively.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.3
• /
• pp.266-273
• /
• 2013

With the worldwide trend of controlling the utilization of fossil fuels inducing global climate change, many efforts will have to be made on securing a sustainable energy supply. Tidal current is a concentrated form of gravitational energy, its resource is significant, but limited locations. To effectively capture tidal current energy from the sea, a group of tidal turbines should be formed and positioned with optimal size and spacing for absorbing from multiple points. Thus, the flow field including turbines becomes a huge domain, a so-called tidal farm. It can be very convenient technically and economically if a whole turbine farm is simulated by means of actuator disc thoery. So, the analysis method using actuator discs coupled with a solution of Reynolds Averaged Navier-Stokes (RANS) equations is adopted for actual tidal turbines. Actuator discs have regions where similar forces imposed by actual turbines are applied to a flow. As working in group formation, turbines naturally have interaction effects on one another. Therefore, the present paper investigate the evaluation on the operating performance of tidal farm in terms of the mutual influence among turbine units with various lateral and longitudinal spacing. Authors expect that results of the present study contribute to the development of tidal farm for the future potential energy.

• Journal of Korea Multimedia Society
• /
• v.19 no.12
• /
• pp.1970-1980
• /
• 2016

The problem of food deficiency is a major discouragement to many low-income developing countries. Most of these countries experience constant danger of hunger, malnutrition and diseases as they are unable to maintain their food supplies mainly due to lack of arable lands and modern crop, livestock and fishery production technologies. In addition, the pollutants resulting from the secondary industries are becoming another serious issue in their food problems. The pollutants mixed in the sands blowing from the mainland China and the toxic waters flowing in the farm land form the industrialized zones are some of the examples. The Vertical Farm, or Plant Factory, proposed in this study could be the best alternative food production system for them. Vertical farm is an efficient food production system that yields relatively a large volume of food materials without environmental risks. The system does not require a large open space and manpower and can minimize the possibility of infiltration of pollutants. This research describes a basic model of the system focusing on determining the optimal sites for it based on the meteorological data concentrating on the atmospheric pollutants. The types and volume of pollutants are analyzed and identified through the big data obtained, followed by visualization of analysis results and their comparisons for better understanding.

• Current Research on Agriculture and Life Sciences
• /
• v.10
• /
• pp.53-65
• /
• 1992

The purposes of this study are to examine the structural differences between the agriculture of Korea and Japan, to clarify the characteristics of Korean agriculture and to determine the extent of development of agriculture in Korea as compared to Japan, In order to do this, the existing literature research reports and secondary data of both countries were used. The main findings are as follows : 1) The percentages of upland fields have inclined to increase in Japan, while those of paddy fields have increased in Korea. However, the size of cultivated land per farm is about the same. 2) The percentage of part-time household was 85% in Japan, against 22% in Korea. 3) Farm household income was more than non-farm household income in Japan, wherease : 92% was non-farm household income in Korea. 4) The farm mechanization is more advanced in Japan than Korea. In conclusion, Korea legs behind Japan in the following areas: (1) Farm mechanization (2) the structure of food consumption ; (3) industrialization and urbanization in Korea progressed more rapidly as compared with Japan ; (4) industry became overconcentrated in the Seoul metropolitan area.

• The Korean Journal of Community Living Science
• /
• v.16 no.3
• /
• pp.97-107
• /
• 2005

This study aims to examine the determinants affecting rural women's participation in community organizations in rural Korea. The data was collected through interviews with 958 rural women among 1,870 respondents who have lived in Up and Myen as an administrative unit of a rural community, and analyzed by the SPSS/PC Win V.10 program. The statistical method utilized for this study was the hierarchy multiple regression model. The major findings of this study were as follows. First, rural women with a high income, a larger farm, or a fruit farm are more likely to participate in agricultural cooperatives. Second, rural women with a high income, a larger farm, who are engaged in full time forming, and grow fruit and special crops, are more likely to participate in cooperative firms. Third, rural women who are educated and have a larger farm, a fruit farm, and high community attachment are more likely to participate in learning organizations. Fourth, rural women who were educated and have small households are more likely to participate in religious groups. Fifth, rural women with a small farm are more likely to participate in civic organizations. Sixth, there was no significance between all of these variables and participation in political parties.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.460-462
• /
• 2009

This study has analyzed the scale, location, resource potential and feasibility of offshore wind farm scientifically and systematically based on the national wind map and GIS (Geographic Information System). For long-term wind power development, this study pursues siting strategy building, selection of target area and deciding development priority as well as the presenting a basis for assessment that are necessary for policy decision making by making theme layers under GIS environment. According to the analysis after organizing technological development by stages, even if only the most suitable sites are developed among the area of offshore wind farm candidates that can be developed under the current technological standard, it has been evaluated as being able to develop about 3 times of the wind power dissemination target until 2012. It is expected that about 5% of territorial water area can be developed in a short-term future while the southern offshore area possessing relatively favorable wind resource than the western offshore has been identified as the most feasible site. While about 23% of territorial water area has been classified as potential area for offshore wind farm development in a long-term future, even Jeju Island and offshore of Ulsan possessing excellent wind resource have been analyzed as feasible sites. The feasibility assessment of offshore wind farm development established by this study is expected to assist national strategy building for accomplishing the wind power dissemination target.

• Korean Journal of Organic Agriculture
• /
• v.24 no.3
• /
• pp.369-383
• /
• 2016

Crop yield insurance program in Korea has rapidly grown not only in quantity but in quality for 15 years since it was introduced in 2001. Despite growth of Crop insurance, performance evaluation for crop yield insurance has not fully been evaluated at the farm, consumer and national level. The purpose of this study is to conduct the performance evaluation for crop yield insurance through estimating the effects of farm revenue stabilization and social welfare increase with three popular insurance items: apple, pear and sweet persimmon. Based on the analysis of social welfare effect, cost-benefit analysis of operating crop yield insurance was conducted at the national level. We found that crop yield insurance stabilizes farm revenue based on the estimated four risk indicators: Coefficient of Variation, Value at Risk, Certainty Equivalence, and Risk Premium. The result of cost-benefit analysis shows that crop yield insurance increases social net benefit by 44.1 billion won for the three items. As a result, crop yield insurance program has contributed remarkably on social welfare as well as farm management and its role will be more important in the future.