• Title/Summary/Keyword: agricultural system

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DEVELOPMENT OF AGRICULTURAL HYDRAULIC ROBOT(Part I) - Dynamic Characteristics and System Identification -

  • Iida, Michihisa;Umeda, Mikio;Namikawa, Kiyoshi
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.820-829
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    • 1993
  • We have developed an agricultural hydraulic robot to operate in the agricultural field. Using the robot, automatic harvesting experiments of watermelon were done. The results are as follows. First, the gripper should be modified its finger. Second, the manipulator and the gripper should be known precisely about dynamic characteristics of them in order to control adequately. Therefore, a new gripper was manufactured on trial by modifying its finger, and in order to known dynamic characteristics of the manipulator and the new gripper, the system identification was carried out with experiments.

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Trends and Directions of Agricultural Extension Services under the Local Autonomy Period in Korea (지방자치시대의 농촌지도업무의 변화와 방향)

  • Lee, Yong-Hwan
    • Journal of Agricultural Extension & Community Development
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    • v.7 no.1
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    • pp.45-64
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    • 2000
  • The purposes of the study were to identify the present status of the agricultural extension services in Korea and its surrounding environment, and to search the desirable ways of improvement under the serious restructuring period occurred by the nation-wide localization, globalization and development of information technology. Agricultural extension services have made great accomplishment in the education for rural people and agricultural technology diffusion, but agricultural extension service system no longer well fits in the changed environment. Agricultural extension services in Korea should restructure the system, function and methods in order to cope with the changing technology and rural society. The objectives of the extension services should be clear and simplified so that the extension workers can understand their role and duty more clearly. The local governments should encourage the extension workers to carry out their services diligently and with the pride. Also, the extension workers should change their mind to fit in the changing world and should improve their capability for their services.

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Agricultural cooperation among the North-East Asian countries

  • Lee, Byung-Oh
    • Korean Journal of Agricultural Science
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    • v.40 no.1
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    • pp.61-78
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    • 2013
  • The following four aspects should be examined in detail to revitalize North-East Asian agricultural cooperation specialized with Korea, Japan, and China. First, quality and safety standards of agricultural food should be unified. Secondly, it is necessary to build a food security cooperative system in North-East Asia. If three countries build the system, they can overcome a problem such as unstable supply and demand due to natural disaster, and also they can cope with food crisis. Thirdly, to establish North-East Asian Agro-valley is needed. After forming food production belt that connects Korea, Hokkaido in Japan, and the three north-eastern provinces in China, it is possible to realize high value-added agriculture with producing and processing of complementary food for partner country. Lastly, trilateral FTA negotiations should be managed carefully with operating the agricultural special zone and exclusion or prolong period of removal of tariff on sensitive items.

An Inquiry into Agricultural Development Theory (1) - Fei-Ranis's Historical Approach and its Relevance to Less Developed World - (농업발전(農業發展) 이론연구(理論硏究) (I) - Fei-Ranis의 경제사적(經濟史的) 접근방법(接近方法)을 중심(中心)으로 -)

  • Lee, Ho Chol
    • Current Research on Agriculture and Life Sciences
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    • v.1
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    • pp.239-253
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    • 1983
  • This study attempted to introduce Fei-Ranis's agricultural development theory and discuss its problem for the rural development of less developed world. Fei-Ranis systematized the development process of Western European economy on the ground of dualism. They divided the process into 4 stages by the concept of 'mode of operation'. Paticularly, they consider agrarian mercantilism as take-off stage and its development were achieved by the increase of trade margin and labor productivity. Especially, they thought that only agricultural revolution through the diffusion of internal exchange economy and construction of tree-star system can accomplish favorable transition to industrial capitalism. In order to promote this agricultural development, less developed world must abolish short-run agricultural policy and propel 'learning by the contact' strategy through 'tree-star system' and 'parellel development.' In reality, it was problematic that the contemporary less developed world is trying, in the course of a few decades, to imitate Western European experience with development over the last four centuries. But Fei-Ranis ignored qualitative aspects of agricultural development by tree-star system and also it is criticized that they considered agricultural development process of less developed world follows only that of Western European classical process.

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Steering Characteristics of an Autonomous Tractor with Variable Distances to the Waypoint

  • Kim, Sang Cheol;Hong, Yeong Gi;Kim, Kook Hwan
    • Journal of Positioning, Navigation, and Timing
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    • v.2 no.2
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    • pp.123-130
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    • 2013
  • Autonomous agricultural machines that are operated in small-scale farmland frequently experience turning and changes in direction. Thus, unlike when they are operated in large-scale farmland, the steering control systems need to be controlled precisely so that travel errors can be minimized. This study aims to develop a control algorithm for improving the path tracking performance of a steering system by analyzing the effect of the setting of the waypoint, which serves as the reference point for steering when an autonomous agricultural machine moves along a path or a coordinate, on control errors. A simulation was performed by modeling a 26-hp tractor steering system and by applying the equations of motion of a tractor, with the use of a computer. Path tracking errors could be reduced using an algorithm which sets the waypoint for steering on a travel path depending on the radius of curvature of the path and which then controls the speed and steering angle of the vehicle, rather than by changing the steering speed or steering ratio which are dependent on mechanical performance.

Development of a Temperature Controller for Microwave-assisted Digestion System for Agricultural Samples (농식품 시료 전처리를 위한 마이크로웨이브 분해기용 온도 제어장치 개발)

  • Mo, Chang-Yeon;Kim, Gi-Young;Kim, Hak-Jin;Kim, Yong-Hun;Yang, Kil-Mo;Lee, Kang-Jin
    • Journal of Biosystems Engineering
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    • v.34 no.5
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    • pp.371-376
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    • 2009
  • Microwave digestion is a preferred pretreatment method for agricultural samples because of its quick chemical reaction and minimum loss of analytes. In this research, a feedback temperature controller was developed to control the temperature inside a vessel for the microwave-assisted digestion system. An existing industrial microwave oven was fitted with the temperature controller for controlling inside temperature of the vessel. Four control methods, On/Off, proportional (P), proportional integral (PI), and proportional integral derivative (PID) were used and compared. Experimental results showed that PID control produced best temperature control performance. The PID controller could maintain the temperature of water sample and rice sample in the digestion system with error range of $-2.5{\sim}3.3^{\circ}C$ and $-1.9{\sim}0.5^{\circ}C$ at set temperature of $170^{\circ}C$, respectively.

Revision of Agricultural Drainage Design Standards (농업생산기반정비사업 계획설계기준 배수편 개정)

  • Kim, Kyoung Chan;Kim, Younghwa;Song, Jaedo;Chung, Sangok
    • KCID journal
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    • v.21 no.1
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    • pp.32-44
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    • 2014
  • In Korea, global warming caused by the climate changes impacted on weather system with increase in frequency and intensity of precipitation, and the rainfall pattern changes significantly by regional groups. Furthermore, it is expected that the regional and annual fluctuation ranges of the rainfall in the future would be more severe. Nowadays, agricultural drainage system designed by the existing standard of 20-year return period and 2 days of fixation time cannot deal with the increment rainfall such as localized heavy rain and local torrential rainfalls. Therefore, it is required to reinforce the standard of the drainage system in order to reduce the agricultural flood damage brought by unusual weather. In addition, it is needed to improve the standard of agricultural drainage design in order to cultivate farm products in paddy fields as facility vegetable cultivation and up-land field crop have been damaged by the moisture injury and flooding. In order to prepare for the changes of rainfall pattern due to climate changes and improve the agricultural drainage design standards by the increase of cultivating farm products, the purpose of this study is to examine the impact of climate changes, the changes of relative design standard, and the analytic situation of agricultural flood damages, to consider the drainage design standard revision, and finally to prepare for enhanced agricultural drainage design standards.

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A Study on Consumers' Purchasing Behavior and Perception of the Low-carbon Certificated Agricultural Products (소비자의 저탄소 인증 농산물 구매행태 및 인식에 관한 연구)

  • Lee, Choon-Soo;Yang, Hun-Min
    • Korean Journal of Organic Agriculture
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    • v.29 no.3
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    • pp.333-358
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    • 2021
  • This study investigates consumers' purchasing behavior and perception of the low-carbon certificated agricultural product. To this end, we surveyed 1,000 consumers and the main findings are as follows. First, Even after six years of national certification, it is important to promote the low-carbon certification system due to insufficient awareness and purchase experience. Second, the certificated area is small at around 5% of the area of environment-friendly agricultural products and GAP certification, and certification is concentrated on fruit trees. Third, an appropriate level of high-priced strategy can be useful considering the cost of low-carbon certification, image management of low-carbon certificated agricultural products, and quality is the most important factor for consumers to consider when purchasing fresh agricultural products. Fourth, consumers recognized that the contribution of low carbon certification in reducing greenhouse gas emissions and preserving the environment was higher than that of environment-friendly agricultural products or GAP certification. Considering that, promotional activities linked to environment-friendly agricultural products and GAP certification may be effective when promoting low-carbon certification. Finally, the Ministry of Agriculture, Food and Rural Affairs is implementing a carbon point system linked to Green Card to revitalize low carbon certification, but 25.7% of consumers are aware of it, and 8.4% have little experience in issuing it.

Analysis of the power requirements of a 55 kW class agricultural tractor during a garlic harvesting operation

  • Seung-Min, Baek;Wan-Soo, Kim;Seung-Yun, Baek;Hyeon-Ho, Jeon;Jun-Ho, Lee;Ye-In, Song;Yong, Choi;Young-Keun, Kim;Sang-Hee, Lee;Yong-Joo, Kim
    • Korean Journal of Agricultural Science
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    • v.48 no.4
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    • pp.1039-1050
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    • 2021
  • The purpose of this study is to measure load data for a 55 kW class agricultural tractor during a harvesting operation and to analyze the required power according to the working conditions. A field test was conducted at three different tractor speeds (1.2, 1.3, and 1.4 km·h-1). A load measurement system was developed for the front axles, rear axles, and for power take-off (PTO). The torque and rotational speeds of the axles and PTO were measured during the field test and were calculated as the required power. The results showed that the total required power was in the range of 4.86 - 5.48 kW during the harvesting operation according to the tractor speed, and it was confirmed that this represents a ratio of 8.8 - 10.0% of the engine rated power. Also, it was confirmed that the required power of the axle and PTO increased as the tractor speed increased. In future studies, we plan to supplement the measurement system for a tractor to include a hydraulic system and perform a field test for harvesting various underground crops.