• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.3
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• pp.2697-2702
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• 1972

Controlling insects and diseases is an important factor for increasing yields of agricultural products. Power sprayer is widely used in cooperative controlling of insects and diseases for the production of rice and fruits. However, farmers need a long hose to use the power sprayer and that presently most of the farmers have hose made abroad. This study was designed to test the change of outside diameter and unit Iength, and to measure the pressure Ioss for three different kinds of hoses made domestically and one made in Japan. The resulte are as follows; 1. The three kinds of Korean-made hoses showed an increase in the length and a decrease in the outside diameter as the spraying pressure increase. The rate of change of the length ranged from 3.5% to 1.6% and the rate of change of the outside diameter from 3.5% to 1.4% respectively. 2. As the length of hose increases, the pressure loss was $3kg/cm^2$ at the end of a 100m of the hose made in Japan, while it was $7-10kg/cm^2$ for Korean-made hoses. 3. The Korean-made hoses were not broken under $27-28kg/cm^2$ of spraying pressure. 4. As a conclusion, the Korean-made hoses can safely be used under continuous rated pressure of the power sprayer, but they can not properly be used for the case of cooperative controlling system where a long hose is reguired because of the heaviness of the hoses and the narrowness of the inside diametar. Hence, it is highly recommended to improve the Korean-made hoses to be used for such a situation.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.11-20
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• 1991

This study was performed to avoid the chemical spraying environment condition during spraying operation for operator's safety through the development of a remote controlled speed sprayer. The summerized results of this study are as followings. 1. The developed VHF electric wave remote controlling system which could operate sixteen type of operation conditions with the circuit channels of 234 was highly adaptable to speed sprayer for the remote control. 2. The commerical wireless telephones adapted the DTMF type electric wave remote control system need not the tranceiver. 3. The wireless electric wave remote control system combined with one-chip microcomputer, which are low cost with compact in size, could be adaptable to the remote control of the speed sprayer for the wheel steering and speed control system, and to the remote control chemical application system.

• Journal of Animal Environmental Science
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• v.17 no.1
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• pp.23-32
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• 2011

The purpose of this study is development of the sprayer that can effectively control pathogens. Image processing was used to analyze the sprayer. Experimental paper in the form of $5{\times}7$ 10 m intervals total of 35 sheets were installed. Experiment used binarized image data obtained by sprayed pigment, to analysis spray volume and distance. The experimental results show that 60 m distance was available to the spray. And spray rate was high up to 30 m. It can be used in livestock farms are expected.

• Journal of Biosystems Engineering
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• v.10 no.2
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• pp.27-35
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• 1985

This study was carried out to determine the optimum size and number of farm machines for various sizes of land coverage of the cooperative farm machinery utilization systems in Korea-namely Saemaul Mechanized Farming Group (SMFG). Fifty-one SMFG were selected from 8 counties in Chonnam province, and ownership, operation and management of farm machinery were surveyed. Annual covered area, cost and the break-even-point area of farm machinery were analyzed on the bases of the surveyed data and the present governmental subsidy policy, and then the optimum level of farm machinery ownership was determined. The results are summarized as follows: 1. The break-even-point areas of the tractors of 22-23ps, 28ps and 47-50ps were estimated as 12.1ha, 15.3ha and 21.6ha, respectively. The optimum size of a tractor for land sizes of 10-20ha, 20-30ha, and 30-40ha were estimated as 22-23ps, 28ps, and 47-50ps, respectively. 2. The break-even-point area of a rice transplanter was estimated as 3.3ha. The optimum numbers of rice transplanter for land sizes of 10-20ha, 20-30ha, and 30-40ha were estimated as 2,3, and 4, respectively. 3. The break-even-point areas of a speed sprayer (attached on power tiller) and a power sprayer were estimated as 114.6ha and 15.3ha, respectively. The optimum numbers of power sprayer for land sizes of 10-20ha, 20-30ha, and 30-40ha were estimated as 2,3 and 4, respectively. A speed sprayer is desirable for an area of more than 30ha coverage. 4. The break-even-point area of a combine was estimated as 10.7ha. The optimum numbers of combine for land sizes of 10-20ha, 20-30ha, and 30-40ha were estimated as 1,2, and 3, respectively.

• Agricultural and Biosystems Engineering
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• v.3 no.1
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• pp.29-34
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• 2002

Two charging methods of electrostatic nozzle, i.e. induction and ionized field corona charging, were designed and evaluated for orchard sprayer application. An artificial (metallic) target was constructed and used in this experiment. The charge-to-mass ratio for the induction electrode was measured by using the Faraday cage. Two conventional pressure-swirl nozzles have been employed with different orifice diameters under the same experimental operating conditions. A commercial pressure-swirl nozzle with orifice diameter of 1.0 was used for the conventional spray. The diameter of the electrostatic was 0.59 mm. The experiment was carried out for individual nozzle sprays at $0^{\circ}$, $20^{\circ}$ and $50^{\circ}$ oriented angles and three nozzles, sprayed simultaneously at a distance of 1.0 and 2.0 m from the nozzle tip to the target. The nozzles were mounted on a carriage with constant speed of 1.26 km/h with a blower attached. The weighing method was employed to evaluate for the spray deposition, ground loss and estimated drift. The results show more promising for the induction charging method, especially at $20^{\circ}$oriented angle at a distance of 1.0 m from the target for a single nozzle and when all three nozzles were operated simultaneously for spray deposition. The results of the induction charging method show promising with the developed electrostatic technique.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.27-36
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• 2018

Effective pesticide applications are needed to assure the quality and economic competitiveness of fruit production and lower the risk of spray drift. Experimental studies have shown that better spray coverage and less driftability require an understanding of the transport of spray droplets within turbulent airflows in the orchard and the interaction between droplet dynamics and tree canopies. This study developed a computational fluid dynamics (CFD) model to predict pesticide flows in the orchard and spray drift discharged from an air-assisted orchard sprayer. The model represented the transport of spray droplets as well as droplets captured by tree canopies, which were modeled as a conical porous model and branched tree model. Validation of the CFD model was accomplished by comparing the CFD results with field measurements. Spray depositions inside tree canopies and at off-target locations were in good agreement with the measurements. The resulting data presented that 38.6%~42.3% of the sprayed droplets were delivered to the tree canopies while 13.6%~20.1% were drifted out of the orchard, part of them reached farther than 200 m from the orchard. The study demonstrates that CFD model can be used to evaluate spray application performance and spray drift potential.

• Journal of Biosystems Engineering
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• v.20 no.3
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• pp.236-244
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• 1995

Droplet size is one of the important factors in the deposition and drift of agrichemical application. In this study, droplet size and its distribution of the three different sizes of ceramic hollow cone nozzles being used in the air carrier sprayer for apple production were investigated at the various nozzle pressures and the three air velocities. The Malvern particle size analyzer were used for the measurement of droplet size and its distribution. The important results emerged from th is study can be summarized as follows. 1. Discharged rate was increase with the increase of the nozzle diameter and pressure, amount of the difference was remarkable between the nozzle diameter of 1.0, 1.2 and 1.5 mm, but no difference were found between the diameter of 1.0 and 1.2 mm in the same nozzle pressure. 2. Mass median diameter were varied as 40~160 ${mu}m$ at the air velocity of 0 m/s, 70~140 ${mu}m$ of 15 m/s and 100~160 ${mu}m$ of 20 m/s 3. It appeared that the air velocity range of 15~20 m/s was desirable for both drift and deposition control in the given experimental conditions.

• Journal of Biosystems Engineering
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• v.33 no.1
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• pp.51-57
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• 2008

The purpose of this study was to develop an optimal path planning program for autonomous speed sprayer in orchard. A digital map which contained coordinate information and entity information including height, width, radius of main stem, and disease of a trees was developed to build an optimal path. The digital map, dynamic programming and order-picking algorithm were used for planning an optimal path for autonomous speed sprayers. When this algorithm applied to rectangular-shaped orchards to travel whole trees, the developed program planned the same working path and same traveling distance as those of created by conventional method. But for irregular-shaped orchards, developed program planned differently and 5.06% shorter path than conventional method. When applied to create path for multi-selected trees, irregular-shaped orchards showed 13.9% shorter path and also rectangular-shaped orchards showed 9.1% shorter path. The developed program always planned shorter path than the path created by conventional method despite of variation of shape of orchards.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.4
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• pp.3991-4000
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• 1975

It is the aim of this study to investigate the influence of the factors in the sprayer nozzle for the travelling distance and to get nozzle design data in relation to the nozz1e with and without swirl plate. The factors of sprayer nozzle are composed of the spraying pressure, the helical angle of swirl plate, the helical groove depth of swirl plate, the distance of vortex chamber the slope of nozz1e cap, the curvature of nozzle cap and the hole diameter of nozz1e cap. The travelling distance and the size of sprayed particle are experimeted indoors by the factorial arrange-ment according to the 5 each level of the above factors. The results of this stupy are summarized as follows; 1. In the nozzle with swirl p1ate there were remarkable significance among factors each other, while without swirl plate were no significance. 2. The helical angle and groove depth in the nozzle with swirl plate were the highest effective factors. The effect of helical angle was very remarked in the quadratic curve with minium value. 3. The correlation betweenthe travelling distance and the sprayed particle size was no high and under 250 micron in the case with swirl plate, and there was higher correlation in the case without swirl plate. 4. The new ideal development of the swirl plate using of the most effective helical angle and groove depth will probably show the possiblities to make effective travelling distance over 8 meters and more over and to make average particle diameter under 300 micron.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.541-545
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• 2008

Hypersensitivity pneumonitis (HP) is an immunologically-mediated disease resulting from repeated exposure to sensitizing agents, such as organic dusts or chemicals. Isocyanate is a volatile and highly reactive chemical that is extensively used in the manufacturing of automobiles, upholstery, and polyurethane foam. Occupational respiratory diseases associated with isocyanate, such as bronchial asthma, are well-known. It is thought that HP is one of the rare diseases induced by isocyanate with a very low frequency worldwide. We report a case of HP in an automobile painting sprayer which appeared to be associated with isocyanate.