Dong-Il Chang

Study on Modification of Inside Environment in Windowless Weaning Piglet House

This study was carried out to determinate the location and the number of air inlet and outlet, optimum air inlet velocity for effective ventilation in windowless weaning piglet house( m) by CFD(Computation Fluid Dynamics) simulation. The weaning piglet house for this experiment was consisted of 11 air inlets and 9 outlets, modified and simulated using CFD code, FLUENT. The simulation result for the original weaning piglet house, which was not modified, showed ununiform ventilation for each room. Therefore, for uniform ventilation, 4 air inlets and 1 outlet were completely closed, and 2 air outlets were partially closed. The simulation result for the modified weaning piglet house showed uniform ventilation for each room and the optimum air inlet velocity of 0.5 .

Study on Optimum Installation of Fan in Standard Hanwoo Loose Barn

The fans installed in standard Hanwoo loose barns (room size : 10 m (width) 5 m (length)) are frequently used to reduce Hanwoo`s heat stress during hot weather and to dry the wet floor. However, the most effective method of installing fans has not been suggested yet. Therefore, this study was carried out to evaluate two methods of installing fans under the ceiling of Hanwoo loose barn by using CFD (Computational Fluid Dynamics) code, FLUENT and to recommend the optimum fan installing method. The fan installation options were fan tilting angles of and (horizontal). The fans of 1 m diameter were installed at 3 m above floor. A velocity scale on 10 cm and 110 cm above floor and air flow pattern were used as the parameters to evaluate the fan installing methods. The fans tilted at angle produced higher wind at 10 cm and 110 cm above floor and more uniform air flow pattern, compared with the fans installed horizontally. Based on these results, fans tilted at angle may help to reduce Hanwoo`s heat stress and will dry the floor better than fans installed horizontally. Therefore, it is suggested that the fans of 1 m diameter in a standard Hanwoo loose barn should be installed at a tilt angle and 3 m above floor with spacing of 5 m at the center of a room column.

Necessary Conditions for Optimal Ventilation of Small Windowless Piglet House with Negative Tunnel Ventilating System

This study was carried out to determine necessary conditions for optimal ventilation of small windowless piglet house (5.2 (W) 12.3 (L) 2.3 (H) m) with negative tunnel ventilating system using CFD (Computational Fluid Dynamics) simulation. The weaning piglet house for this experiment was consisted of 4 rooms (520 (W) 300 (L) cm), 3 fences (70 (H) cm), 1 air inlet (350 (W) 2 (H) cm) and 1 exhaust fan (50 (D) cm), and simulated using CFD code, FLUENT. The simulation results for the original weaning piglet house showed ununiform ventilation for each room. Therefore, to uniformly ventilate all rooms, the heights of the air inlet and first fence were modified to 3 cm and 100 cm, respectively. The simulation result f3r the modified weaning piglet house showed uniform ventilation for all rooms and the optimum air inlet velocity of 1.4 m/s.

Development of Automatic Sorting System for Green Pepper Using Machine Vision

Abstract Production of green pepper in Korea has increased due to customers preference and a projected ten-year boom. This study was carried out to develop an automatic grading system for green pepper using machine vision. The system consisted of three main components - a feeding and individuation mechanism, an image inspection and processing system, and a discharging system. The green peppers were separately fed into the machine vision system by a vibration motion and a velocity difference transport provided by a bowl feeder and a belt conveyor, respectively. Images were taken using a CCD camera and a color frame grabber. Using an on-line grading algorithm developed with Visual C/C++, the green peppers could be graded into four classes (large, medium, small sizes, and high curved shape), based on the measurement of two geometric parameters (length and flexure), by automatically activating air nozzles located at each container of different grades in the discharging system. The first derivative of thickness profile was used as a parameter to remove the stem area of segmented image of each pepper. At a sorting speed of 0.45 m/s, the grading accuracies for large, medium and small peppers were 86.0, 81.3 and 90.6 %, respectively. The system provided the performance capability of 121 kg/hr, which is about five times higher than that obtained with conventional manual sorting operations. The prototype system was economically feasible to sort green peppers by showing a cost reduction of about 40 %.

Development of an Automated Measurement System for Dilution Process and Spraying Amount of Disinfectant

Purpose: The objectives of this study were to develop an automated disinfectant dilution system, and an automated data management system for spraying amount for resolving uncertainty problem. Methods: Proper diluting rate was made by a controlled volume pump for liquid disinfectant and a screw conveyer pump for solid disinfectant. The water capacity of disinfecting system of 400 L was controlled by two water level sensors. The water quantity of water tank was controlled by the signals which were produced by the water level sensors. Signals were processed by Labview Programming, and ON/OFF of solenoid valve that was used for controlling water supplying to water tank, was controlled by SSR. The operating time of pumps for disinfectant was controlled quantitatively. A turbine flowmeter was used for development of automated measurement system for spraying amount of disinfectant. In order to save the flowmeter data and to control the spraying system, a multi-function data logger was used, and it was processed and saved in Excel file by a program developed in this study. Results: Labview 2010 was used for programming to control the automated measurement system for spraying amount of disinfectant. Results showed that the relationship between flowmeter value and time had a significant linear relationship such as 0.99 of R 2 . Generally, 6.74 L/s of diluted disinfectant is sprayed for a vehicle passing through the disinfection system (about 15 seconds). Test results showed that average error between the measured spraying amount and the flowmeter data was 50 mL, and the range of error was 1.3%. Since the amount and time of spraying could be saved in real-time by using the spreadsheet files which could not be mod ified arbitrarily, it made possible to judge objectively whether the disinfection spraying was performed or not. Test results of spraying liquid and solid disinfectant showed that the errors between the measured discharge rate and the theoretical one were ranged within 3-4% for various dilution rates. Conclusions: The disinfection system developed would be working accurately. The automated spraying data base management system satisfied the purpose of this study. The auto mated dilution process system developed in this study could discharge liquid and solid disinfectant with accurate dilution rate, relatively.

The Evaluation of a General Purpose Bale System Performance and Its Bale Quality

Purpose: The objectives of this study were to develop a general purpose baler system that is appropriate for the domestic forage cultivation environment and operated by the medium size tractor for production of bale silage made of green forage crops, and to test its performance. Methods: In a first experiment, the time of formation per one bale and densities of bales that are produced from bale system, were measured. In a second experiment, power requirement was measured by a power measurement system manufactured during bale system work. Results: The power measurement system was constructed with strain-gage sensors to measure torque of a PTO axle and proximity sensor to measure rotating speed of a PTO axle. Thus, the power requirement was calculated by PTO torque and PTO rotating speed. For evaluation of bale quality, the samples of bales were analyzed for contents of moisture, ADF, NDF and TDN. Conclusions: If the results of this study will be utilized, the coefficient of utilization of agricultural machinery will be increased by the operation of a medium size tractor that is a major disseminated tractor in farm, and it will contribute tremendously to make a forage production base for livestock farms.

Study on Priority Selection of Export Strategic Core Technologies for IT Fusion Next Generation Agricultural Machines

, 2011)The objective of this study was to develop the export strategic core technologies for IT fusion next generation agricultural machines by the analysis of comprehensive and cooperative systems of industries, universities, and institutes. In order to achieve the objective of this study, an expert panel was formed and operated. The first survey was conducted by the Delphi method. For this the export strategic core technologies were surveyed and analyzed using the questionnaire. Based on the results of the first survey, the second survey was conducted. The questionnaire used for the second survey was designed by results of the first survey. The results of the second survey was analyzed by AHP method. The third survey was conducted based on the second one, and the final results were analyzed and the export strategic core technologies were developed through the expert meeting. The study results showed six export strategic core technologies as the followings : 1) environment-friendly engine technology for high performance 2) high performance/high efficiency power transmission system technology 3) development of measurement system technology for safety of agricultural products 4) field application of sensor networks 5) large size combine development technology for high performance 6) quality evaluation technology for agricultural products.Keywords : IT fusion, Export strategic core technologies, Agricultural machine, AHP method*Corresponding author: Byoung-Kwan ChoTel: +82-42-821-6715; Fax: +82-42-823-6246E-mail: chobk@cnu.ac.kr

Necessary Conditions for Optimal Ventilation of Small Negative Pressure Ventilating Piglet House with Corridor and Attic for Preheating

This study was carried out to determine necessary conditions for optimal ventilation of small windowless piglet house (4.0 (W) 11.0 (L) 2.6(H) m) with corridor and attic for preheating using CFD (Computational Fluid Dynamics) simulation. The experimental weaning piglet house was consisted of a corridor, an attic, 4 rooms (3.0 (W) 2.75(L) m), 3 fences (0.7(H) m), 5 air inlets and 2 exhaust fans (0.4 (D) m) and simulated using CFD code, FLUENT. The simulation results for the experimental weaning piglet house showed that each room was uniformly ventilated under all the experimental conditions and air velocities at 0.1 m above floor are less than 0.15 m/s for 0.75 m/s and 1.0 m/s of air inlet velocity but 0.61 m/s for 1.25 m/s. The simulation results are similar to the measured results. Considering the air flow pattern, ventilating efficiency, air velocity at 0.1 m above floor and cold stress of weaning piglets and so on, the optimum velocity of air inlet might be 1.0 m/s.

Characteristics of Vibrations Produced by Egg Sorters Exported for Asian Laying Hen Farming

Abstract In this study, mechanical vibration generating cracked-eggs was measured and analyzed using commercial egg sorter. Vibration measurement of egg sorter was carried out by a FFT Analyzer ZonicBook/618E and acceleration sensors on the transfer system and packing system. The vibration measured on the transfer system ranged from 202.03 to 396.87 G (where, G=9.81 m/s 2 ), and the magnitude of the impulse that eggs received from the transfer system was about 20.60~39.24 N in these tests. In the packing system, the vibrations were 7.98∼9.05G, and the quantities of impulse imparted on the eggs were about 3.92∼4.91N.

Effect of Heat Stress on Laying Hen Performance

This study was conducted to determine the effect of heat stress on laying hen performance during summer. A total of 180 Hyline-brown layers, 98 days of age, were housed in a enclosed house. The daily maximum temperature in the house was ranged . The egg production was markedly fallen than other days when daily maximum temperature in the layer house became more than . As water intake and feed intake increased to and , the egg production soared. But it was hardly increased more than them. Based on these results, layer house roof should be amply insulated to improve the egg production of layers. If not insulated, the shade curtain should be installed above roof and cool water sprayed before and after 2 p.m. And layers should be provided cool drinking water of about in the day time.