• 어항어장
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• s.80
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• pp.38-42
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• 2007

아오모리현에서는 천연해초 조장 및 이식 해초 조장에 해삼 치자 착저를 기대할 수 있는 가리비 패각을 살포해 해삼 유생의 착저효과나 살포 후의 생물 모습의 변화 등에 대하여 조사를 실시하고 있다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.86-91
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• 2002

이상의 연구를 요약하면 다음과 같다. 1. 시비량의 계산식에 의해 계산된 실제 비료의 투입예정량은 균일시비구획은 86.74kg, 변량 시비구획은 80.84kg이였고, 실제 변량시비구획에 살포된 비료의 양은 68.76kg로서 투입 예상량의 -14.94%로 나타났다. 2. 실제 투입된 비료의 양이 적은 것은 74번에서 78번사이의 구획에서 호퍼의 출구에 덩어리진 비료에 의해 막혀 비료가 살포되지 않았던 것과 28번 구획에서 호퍼안의 비료가 바닥나서 비료가 살포되지 않았던 것이 주된 원인으로 확인되었다. 3. 벼의 질소보유량으로 계산된 예상 시비량과 실제 모터의 회전수에 의해 계산된 실제 시비량과의 관계는 Y=-0.063+0.912X라는 회기직선으로 나타났고, r값은 0.965로서 변량살포 작업은 74번∼78번, 28번 구획을 제외하고는 잘 된 것으로 평가되었다. 4. 수확량과 CV값은 전 구획에서 7.04t/ha, 7.71%로서 균일시비구획에서는 7.13t/ha, 4.84%, 변량시비구획에서는 6.96t/ha, 9.77%로 나타났다. 변량시비구획에서 수확량이 적고 CV값이 크게 나타난 이유는 x9구획의 생육상태가 좋지 않았기 때문이며 변량시비구획에서 x9구획의 데이터를 제외한 결과는 수확량이 7.16t/ha, CV값은 7.91%로 나타났다. 5. 변량시비를 적용하여 시비량을 15% 줄이더라도 수확량에는 커다란 변동이 없다는 것을 확인할 수 있었고 좀더 정확한 생육진단과 관리가 이루어진다면 각 구획에서 수확량의 변동을 줄이는 것이 가능하리라 생각한다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.141-151
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• 2010

Harmful algal blooms (HABs), commonly known as red tides, are aquatic phenomena caused by the rapid growth and accumulation of certain microalgae, which can lead to marked discoloration of surface waters, and severe impacts on public health, commerce, and the environment. In South Korea, the red tides have been a serious and recurrent problem, especially along the south coast. Plenty of yellow loess was used to control an outbreak of the red tides for 15 years from 1996 until now. Yellow loess was almost sprayed in the vicinity of a large fish farming industry. In this research, the distribution characteristics and density distribution of zooplankton were investigated in autumn (Oct. 2008) and spring (Apr. 2009) using volume backscattering strength (SV) calculated by the zooplankton collected with north pacific standard (NORPAC) net and the echo intensity measured with ADCP at stations on the study area in the spraying ocean of yellow loess (SOYL), and the non-spraying ocean of yellow ocean (NOYL) by the red tide generating every year. The species number and the individuals per unit volume of the zooplankton collected in NOYL was high and it which was collected in SOYL was low. As a result of comparing the volume backscattering strength ($SV_c$) calculated by species and length of the zooplankton collected with NORPAC net with the volume backscattering strength ($SV_m$) calculated by the echo intensity measured with ADCP at stations on the study area, although $SV_c$ and $SV_m$ of NOYL were generally in agreement, $SV_m$ of SOYL was higher than $SV_c$ 4.3dB, i.e. ADCP is greatly influenced by suspended solid in SOYL. The horizontal distribution map of $SV_m$ at the study area in autumn (Oct. 2008) and spring (Apr. 2009) was drawn. $SV_m$ of SOYL is higher than NOYL and autumn is higher than spring. $SV_m$ can suppress the overestimate or underestimate of $SV_c$.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.119-129
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• 1986

Disappearence of the trichlorfon (Dipterex) in the forest, following aerial to control Agelastica coerulea B., were studied by sampling deposits on slide glasses, soils, water, and leaves, and analysing with a gas chromatograph equipped with an electron capture detector. By analysing the amount remained on slide glasses, it was shown that the pesticide was adequately sprayed and nearly all deposit was lost in a day. The amount deposited under the tree was about 1/100 of the amount at an exposed site. Concentration of trichlorfon in creek water was 10 to 100 times as high as the acute toxic level to zooplankton for 6 to 24 hours, The rain could recontaminate the stream water up to the toxic level. Loss rate of trichlorfon from soils showed variations by sampling sites and was generally slower than from slide glasses. Amount deposited on leaves were less than the calculated or expected amount. The loss from leaves were similar to that from soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.285-290
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• 1984

The effects of retardants B995 and CCC on the growth and yield of soybean cultivar, kwanggyo, were investigated. The 3 application times(4th, 5th and 6th trifoliate leaf stage) combined with 4 concentrations (500, 1000, 2000 and 3000 ppm) were treated, and the retardant solutions were sprayed on the foliage. Only stem length in retardants, rate of podding in application times, and, in concentrations, stem length, number of branch, number of pod per plant and grain yield, were significant. In the inhibition of stem elongation, B995 was more effective than CCC, and rate of podding was the highest in the 4th leaf-spraying. The highest concentration, 3000 ppm, was the most effective in the inhibition of stem elongation and in the increase of number of branch and pod, rate of podding, and in yield. The number of node of mainstem, dry stem weight, chlorophyll and 100 grain weight were not significant with any treat. Yield had positively correlated with number of branch and pod, and rate of podding but negatively with stem length. The retardants was thought to be considerably conducive to the increase of yield.

• Smart Media Journal
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• v.8 no.4
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• pp.38-45
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• 2019

When there is a spray flow such as from a pesticide nozzle, winds affect the droplet flow of a rotary-wing drone accompanied by a strong wake, with a severe oscillation. Especially, during forwarding flights or when winds come from the side, compare to a simple hovering flight as the droplet is in the effect of aerodynamic drag force, the effect of spraying region becomes even larger. For this reason, the spraying of pesticides using drones may cause a greater risk of scattering or a difference in droplet dispersion between locations, resulting in a decrease in efficiency. Therefore, through proper numerical modeling and its applied simulation, an indication tool is required applicable for the various flight and atmospheric conditions. In this research, we completed both experiment and numerical analysis for the strong downwash from the rotor and flight velocity of the drone by comparing the probability density function of droplet distribution to build a spraying system that can improve the efficiency when spraying droplets in the pesticide spray drone.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.159-166
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• 2008

This research was carried out to test and analyze capacity of the long distance sprayer fan in large livestock farmhouses. Long distance sprayer was manufactured to be able to spray a lot of water, which was a solvent for agricultural chemicals and black dye with the maximum spraying distance of 140 m and the effective spraying distance of 100 m. The spraying quantity and the distance were measured the intensity values of images within A4 papers, which absorbed the agricultural chemicals by spraying by binary image processing. These A4 papers were fixed upon the height of 1 m from soil ground at regular 10 m interval. After the A4 papers were collected and analyzed the intensity values of gray level. Gray level was ranged from 0 to 255, where 0 was black and 255 was white. A4 paper was fallen down from the stick at 10 m distance, because there were too large amount of sprayed water with black dye. Also, the paper showed low gray level at distance 30 m because of dropping lots of black water. The intensity value of gray level was showed almost less than 200 on the A4 papers between the distance 20 m and 100 m, which meant equality of spraying quantity. Additionally, it was possible to spay agricultural chemicals of until 180 m. Throughout this research, long distance sprayer could apply for preventing hoof-and-mouth disease in large livestock farmhouses.

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.130-138
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• 1998

This experiment was conducted to study the effect of ethephon(100mg.L$^{-1}$ ) and calcium carbonate (10000mg.L$^{-1}$ ) on the acceleration of peel coloration of ‘Miyagawa Early’ Satsuma Mandarin in the plastic house. The foliar application treatments were conducted once. twice or 3 time at intervals of 15 days from degreening of the fruit apex. Peel coloration of a value by spraying ethephon ＋ clef-non was increased with treatment frequency. The a/b values ran similar to this trend. As a result of this, peel coloration was accelerated by foliar application of ethephon ＋ clef-non. Glucose and fructose did not differ significantly among foliar application frequencies. Sucrose and total sugar increased as foliar application frequency increased, but there was no significant di(ference among foliar application frequency group. The brix values were higher than 12˚BX in all treatments. However, a distinct difference between the control Brix value and the values for the treatment groups was found only in the level 3 frequency group.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.264-270
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• 2016

This study was conducted to compare of the pesticide residue amounts in fruit trees applied by different sprayers and spray volumes. Apple tree was used as a sample tree, and speed sprayer, power sprayer and knapsack motorized sprayer were tested. For similar sprayer and spray volume, the concentration of fluquinconazole and flusilazole in apple leaves were obtained respectively, for speed sprayer 8.33 and 2.15 mg/kg, for power sprayer 4.56 and 1.10 mg/kg, and for knapsack 4.55 and 1.12 mg/kg. The results showed that the treatment using speed sprayer had highest efficiency. The pesticide residues in apple leaves sprayed by 3 different spray volumes (560, 336 and 230 L/10a) using speed sprayer were 10.76 mg/kg, 8.32 mg/kg, 6.04 mg/kg on fluqinconazle and 3.04 mg/kg, 2.14 mg/kg and 1.47 mg/kg on flusilazole, respectively, indicating that the higher the volume, the higher the residues. The results from this study can be used as scientific basis for evaluating the field trial data for pesticide registration and the spray volume setting for fruit trees in Korea.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.403-413
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• 2008

This study was conducted to select excellent tank mix combinations of pesticides for aerial application by manned helicopter. Among 209 pesticide combinations of 3-way tank-mixing for aerial application, a total of 93 recommendable combinations including tricyclazole SC+validamycin-A SL+imidacloprid SL were finally selected for the simultaneous control of key pests on paddy rice such as blast, sheath blight, brown planthopper and moth. The selected combinations were not phytotoxic to rice plants and nearby non-target crops, and excellent in physicochemical properties of ultra low volume (ULV) spray solutions. The efficacies on sheath blight, brown planthoppers and white-backed planthoppers of pesticides sprayed by aerial application were similar to those of pesticides by conventional spraying. Total cost of aerial application in paddy rice was very economical as one fourth level of that of conventional spraying.