• Title/Summary/Keyword: spreader

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Performance of Mini-Sprinkler - (2) Size of Droplets (미니 스프링클러의 살수 기능 - (2) 살수 입자의 크기)

  • 서상룡;성제훈
    • Journal of Bio-Environment Control
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    • v.6 no.3
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    • pp.183-189
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    • 1997
  • This study was performed to Investigate size of droplet sprinkled from mini-sprinkler. Twelve different kinds of the sprinkler having various structures and sizes of nozzle orifices were selected and tested. Diameters of the droplet reached at several distances from a sprinkler were measured by a machine vision system and the volume median diameters (VMM) were determined statistically. The size of droplet was not affected much by the size of nozzle orifice of a sprinkler but was rather more affected by structure of the sprinkler, especially by the shape of spreader of the sprinkler. Experiment of varying pressure of sprinkling water validated that the size of droplet was inversely proportional to water pressure powered by 1/3. Hence the size of droplet at any water pressure could be easily estimated from experimental data. The size of droplet increased as travel distance of the droplet increases in a relationship of and order function. The size of droplet of the tested sprinkler were in the ranges of 100-300fm within 1m of droplet travel distance, 230~470${\mu}{\textrm}{m}$ within 1~2m of droplet travel distance and 300~770${\mu}{\textrm}{m}$ within 2~3m of droplet travel distance.

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Fungicidal Activity Enhancement of KNF-1002 Against Barley Powdery Mildew by Facilitating Foliar Uptake and Deposition (KNF-1002의 경엽 침투성과 부착량 증진에 의한 보리 흰가루병 방제 효과)

  • Yu, Ju-Hyun;Choi, Gyung-Ja
    • The Korean Journal of Pesticide Science
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    • v.14 no.3
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    • pp.272-279
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    • 2010
  • KNF-1002, a new fungicide candidate, is very effective for protecting crops against plant diseases, but its curative activity against barley powdery mildew is negligible due to its weak penetrability into plant leaf. To select the most efficient activator and, at the same time, spreade-sticker, foliar uptake and deposit of aqueous spray formulations containing non-ionic or anionic surfactants and fatty acid alkyl esters as an adjuvant were assessed by using Congo Red method. In the absence of activator, only 0.1% of the applied active ingredient was absorbed by barley leaves 24 h after spraying with an aqueous acetone containing KNF-1002 100 mg/L. But, non-ionic surfactants (500 mg/L), such as heptaethylene glycol monooctadecenyl ether (OE-7), dodecaethylene glycol monohexadecyl ether (CE-12), so facilitated KNF-1002 uptake that the uptake was increased up to 48.5%. To wheat plant, the addition of surfactants in spray solution of KNF-1002 also increased the foliar uptake and deposition of active ingredient, but its efficiency varied according to the kind of fatty alcohol moiety of polyoxyethylene surfactant. KNF-1002 formulations containing nonaethylene glycol monododecyl ether (LE-9) as an activator and spreader-sticker showed remarkable increases of fungicidal activity against barley powdery mildew.

Development Feasibility of Water-Floating Fungicide Formulation for the Control of Sheath Blight(Caused by Rhizotonia solani) in Rice (수도(水稻) 문고병방제용(紋枯病防除用) 수면부유제(水面浮遊劑)의 개발(開發) 가능성(可能性)에 관(關)한 연구(硏究))

  • Oh, Byung-Youl;Kim, Jin-Hwa
    • Applied Biological Chemistry
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    • v.31 no.3
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    • pp.226-233
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    • 1988
  • Some physico-chemical properties and biological activities of new fungicide formulations were tested to investigate a feasibility of water-floating formulation development for sheath blight control in rice. Pencycuron[1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] and flutolanil$({\alpha},{\alpha},{\alpha}$-trifluoro-3'-isopropoxy-O-toluanilide) were chosen as toxicants for the formulations. Vegetable oil and surface active agents were used as a floating agent and spreader, respectively. All the formulations tested showed an excellent spreadability on the water having over $35cm^2/mg$ and were chemically stable, which the degradation rates of active ingredients were less than 10% after 12 weeks of storage at $50^{\circ}C$. Most of the applied test formulation of pencycuron was retained within 0.5cm of the surface paddy water, while that of flutolanil was vertically dispersed in the water. Inhibition activity of the tested pencycuron formulation on the sclerotia germination of the pathogen in paddy water was maintained over 30 days after the formulation treatment. Control effect of 4% pencycuron water-floating formulated with surface active agent of hydro-lipophyllic balance 4.3 on the disease in rice was equal to the reference fungicide(pencycuron 25% WP) when the former was treated one day before the transplantation of rice seedlings. Overflowing the submerged paddy water after the formulation treatment resulted in a deterious effect on the disease control.

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A COMPARATIVE STUDY ON THE CANAL CONFIGURATION AFTER SHAPING BY PROFILE, PROTAPERTM AND K-FLEXOFILE IN SIMULATED CANALS WITH DIFFERENT ANGLES OF CURVATURE (ProFile, ProTaperTM K-Flexofile 근관 성형시 근관의 만곡도에 따른 근관 형태 변화 비교연구)

  • Lee, Bo-Kum;Kim, Dong-Jun;Hwang, Yun-Chan;Hwang, In-Nam;Oh, Won-Mann
    • Restorative Dentistry and Endodontics
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    • v.30 no.4
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    • pp.294-302
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    • 2005
  • The purpose of this study was to evaluate the canal configuration after shaping by ProFile. ProTaper and K-Flexofile in simulated resin canals with different angles of curvature. Three types of instruments were used: ProFile. ProTaper. K-Flexofile. Simulated root canals. which were made of epoxy resin. were prepared by ProFile. ProTaper with rotary instrument using a crown-down pressureless technique. and hand instrumentation was performed by K-Flexofile using a step-back technique. All simulated. canals were prepared up to size 25 file at end-point of preparation. Pre and post instrumentation images were recorded with Scanner. Assessment of canal shape was completed with Image Analysis program. Measurements were made at 1. 2. 3. 4. 5. 6. 7. 8. 9 and 10mm from the apex. At each level. outer canal width. inner canal width. total canal width. and amount of transportation from original axis were recorded. Instrument deformation and fracture were recorded. Data were analyzed by means of one-way ANOVA analysis of variance and the Sheffe's test. The result was that ProFile and ProTaper maintain original canal shape regardless of the increase of angle of curvature than K-Flexofile. ProFile show significantly less canal transportation and maintained original canal shape better than ProTaper.

Triangular Resection of the Upper Lateral Cartilage for Middle Vault Deviation

  • Ryu, Gwanghui;Seo, Min Young;Lee, Kyung Eun;Hong, Sang Duk;Chung, Seung-Kyu;Dhong, Hun-Jong;Kim, Hyo Yeol
    • Clinical and Experimental Otorhinolaryngology
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    • v.11 no.4
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    • pp.275-280
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    • 2018
  • Objectives. Middle vault deviation has a significant effect on the aesthetic and functional aspects of the nose, and its management continues to be a challenge. Spreader graft and its modification techniques have been focused, but there has been scarce consideration for removing surplus portion and balancing the upper lateral cartilage (ULC). This study aimed to report the newly invented triangular-shaped resection technique ("triangular resection") of the ULC and to evaluate its efficacy for correcting middle vault deviation. Methods. A retrospective study included 17 consecutive patients who presented with middle vault deviation and underwent septorhinoplasty by using triangular resection at a tertiary academic hospital from February 2014 and March 2016. Their outcomes were evaluated pre- and postoperatively including medical photographs, acoustic rhinometry and subjective nasal obstruction using a 7-point Likert scale. Results. The immediate outcomes were evaluated around 1 month after surgery, and long-term outcomes were available in 12 patients; the mean follow-up period was 9.1 months. Nasal tip deviation angle was reduced from $5.66^{\circ}$ to $2.37^{\circ}$ immediately (P<0.001). Middle vault deviation also improved from $169.50^{\circ}$ to $177.24^{\circ}$ (P<0.001). Long-term results were $2.49^{\circ}$ (P=0.015) for nasal tip deviation and $178.68^{\circ}$ (P=0.002) for middle vault deviation. The aesthetic outcome involved a complete correction in eight patients (47.1%), a minimally visible deviation in seven patients (41.2%) and a remaining residual deviation in two patients (11.8%). Pre- and postoperative minimal cross-sectional areas (summation of the right and left sides) were 0.86 and 1.07, respectively (P=0.021). Fifteen patients answered about their nasal obstruction symptoms and the median symptom score had alleviated from 6.0 to 3.0 (P=0.004). Conclusion. Triangular resection of the ULC is a simple and effective method for correcting middle vault deviation and balancing the ULCs without complications as internal nasal valve narrowing.

Mini-implant with additional retentive structure by using digital method (부가적인 유지구조를 가진 미니 임플란트의 디지털 수복 증례)

  • Hwang, Su-Hyun;Bae, Eun-Bin;Cho, Won-Tak;Huh, Jung-Bo
    • The Journal of Korean Academy of Prosthodontics
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    • v.60 no.1
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    • pp.119-126
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    • 2022
  • Mini-implant has been reported as an alternative method to conventional diameter implants in the treatment of mandibular anterior region with narrow ridge. However, one-piece type mini-implant showed biological and technical complications, such as peri-implantitis by residual cement and prosthetic detachment. Recently, one-piece type mini-implant with additional retentive structure has been introduced to increase the retention and stability of the mini-implant. The mini-implant is based on spreading the upper retentive structure with a spreader and connected it with the inner surface of the zirconia prosthesis. In two cases, we tried to reduce these complications through the mini-implant on the narrow mandibular anterior region, and it was possible to reduce the overall treatment period through a digital system. In this case report, restoration using the digital mini-implant system showed improvement of patient satisfaction on the aspect of function and esthetic in the narrow mandibular anterior region.

Effect of Mechanical Working System on Labor-Saving in Wheat Cultivation (밀 기계화 작업체계에 의한 노력 절감 효과)

  • Kim, Hag-Sin;Kim, Young-Jin;Kim, Kyeong-Hoon;Lee, Kwang-Won;Shin, Sang-Hyun;Cheong, Young-Keun;Park, Ki-Hoon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.4
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    • pp.331-336
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    • 2012
  • This study was carried out to evaluate the wheat cultivation system to reduce costs and mechanize wheat production. A field study was conducted for 2 years (2009 to 2010) at the National institute of crop science, Iksan, Korea. We used working system I and working system II for the experiment. Working system I is used a multiple machine attached with a spreader tractor (seeding, fertilization, seed coverage, and weed control functionality) and working system II is used a multiple machine with a tractor which works for simultaneous job when seeding step (seeding, fertilization, and seed coverage). Sowing to harvesting operation time is 118 hours/ha for mechanize with conventional planting. Working system I is a multiple machine and a combine machine with a tractor, which worked 26 hours/ha lower than conventional planting. Working system II is 18 hours/ha lower than conventional planting. The reduced work efforts of working system I and II were 78% and 85% respectively. The growth and yield of wheat according to working system I and II is lower than conventional planting. Therefore, a multiple machine needs to study for appropriate seeding rate. Mechanization cost in consideration of the mechanical break-even point when the working system I is 3.7 ha and working system II is 4.2 ha. The farm income is enhanced by working system I (778,110 won/ha) and working system II (849,930 won/ha). The results showed that application of a multiple machine lowered costs of wheat production.