• Title/Summary/Keyword: surface rolling

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Comparison of Bentgrass Recovery Speed on Golf Green Followed by Methods of Ball Mark Repair Practise (골프장 그린의 볼마크 수리방법에 따른 벤트그래스의 회복속도 비교)

  • Park, Jong-Hwa;Lee, Jae-Phil;Kim, Doo-Hwan;Joo, Young-Kyoo
    • Asian Journal of Turfgrass Science
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    • v.24 no.2
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    • pp.211-217
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    • 2010
  • This study was conducted to investigate a proper method of ball mark repair by comparing the creeping bentgrass recovery speed on golf course green treated by various methods of ball mark repair. Nine general repairing methods were tested and compared; control (no repair, A type), two common methods of USGA (B type) and GCSAA (C type), three methods with fork shaped hand set performing at Korean golf courses (Ansung Benest, D; Sky72, E; Lakeside, F type), and three methods using the repair machine with 6, 8, or 14 teeth (G, H, I type, respectively). Three creeping bentgrass cultivar of 'Penncross', 'T-1', and 'CY-2' were tested in this field experiment. This test was carried out from September to November in 2009 at the nursery on the Seoul Lakeside Golf course. The average speed of turfgrass recovery after various ball mark repairing methods have been ranked as in the order of E, D, C, B, F, I, H, G, and A. The methods of hand practise showed more effective results than repair method using machines. The ball mark recovery speeds of 'Penncross' were in the order of E, D, B, C, F, I, H, and A. In the case of 'T1' and 'CY-2', similar orders were showed as D, E, B, F, C, H, I, A, G and the order of D, E, C, F, B, H, G, I, A, respectively. The ball mark recovery speed among creeping bentgrass cultivar resulted in the order of 'CY-2', 'Penncross', and 'T-1'. The most proper method of ball mark repair was repair method using a hand set tool especially the method of the Sky72 Golf course (E type). At the first, remove a damaged grass area with fork and tap. And then gather the side grasses into the center area with pulling the grasses with fork. After that, make harden and flat on the turf surface by pounding and rolling with the round wooden stick. The final Nstep, water the repaired grass surface. This ball mark repairing practise showed a most rapid and proper recovery method on creeping bentgrass green.

A Study on characteristics of planosols in korea -Part I Yeongog series (우리나라에 분포(分布)된 반층토(盤層土)의 특성(特性)에 관(關)한 연구(硏究) -제(第)1보(報) 연용통(延谷統)에 관(關)하여)

  • Um, Ki Tae;Cho, Seong Jin
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.2
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    • pp.45-51
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    • 1975
  • The morphological, physical, chemical, and mineralogical characteristics of planosols in Korea were studied in an effort to establish the suitabilition of the planosols for agricultural development. The Yeongog series which are planosols were established in Korea. Results from the Yeongog series are briefly as follows : 1. Morphologically, the surface soils are brown to dark brown friable loam and subsoils are of varied colors but mainly are dark brown, black and pale brown mottles. The texture of these horizons are silty clay loam with moderate to strong platy structure and clay cutans are on the ped faces. The consistences of these horizons are extremely compact and hard when moist and sticky, plastic when wet. The substrata show varied soil colors and loam to clay loam. 2. Physically, the clay content of the Yeongog soils is highest in the subsoils and gradually decreases below the subsoils. Water holding capacity and bulk desity is higher than in other mineral soils. 3. Chemically, the organic matter content is low and soil reaction ranges from very strongly to strongly acid. The cation exchange capacity is medium and base saturation a high. Active iron, easily reducible manganese and available silicate are high compared with normal soils. 4. In chemical composition of clay fraction of the Yeongog series, sesquioxide ratio, $Fe_2O_3$, $K_2O$ and MgO are high. The cation exchange capacity of the clay fraction is also very high. 5. The clay minerals in Yeongog series are mainly kaoline, vermiculite with Al interlayers and illite. The quarts, primary minerals are in the Yeongog soils. 6. These soils are formed in a warm, humid climate under native grasses on the terraces and rolling or hilly footslopes. In soil classification, the Yeongog soils are classified planosols with claypan. According to 7th approximation system in U.S.A., the Yeongog series are classified as Fragiudalfs because they have an argillic horizon, a hard pan and a high base saturation which is more than 35 percent and classified as Eutric Planosols by FAO/UNESCO classification system.

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Characteristics of Temperature, Humidity and PPF Distribution by Covering Method and Environmental Control in Double Covering Greenhouse (이중피복 온실의 피복방법과 환경조절에 따른 온습도 및 광합성유효광량자속 분포 특성)

  • Lee, Hyun-Woo;Sim, Sang-Youn;Kim, Young-Shik
    • Journal of Bio-Environment Control
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    • v.21 no.1
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    • pp.1-11
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    • 2012
  • The objective of the present study is to provide data needed to find double covering method to be able to improve environment of temperature, humidity and PPF in tomato greenhouse. The distribution charts of temperature, humidity and PPF which were measured in environment control conditions such as thermal insulation, air heating, roof ventilation and air fog cooling in conventional and air inflated double layers greenhouses were drawn and analysed. The thermal insulation effect of the air inflated greenhouse was the same as that of conventional greenhouse because the temperature between insulation curtain and roof covering material was equal in heating season. The ventilation effect of the air inflated greenhouse was superior to the conventional greenhouse. The temperature distribution in the fog cooled greenhouse was uniform and the cooling effect was about $3.5^{\circ}C$. The condensation on the roof covering surface could be controlled by removing the moisture between insulation curtain and roof covering by using humidifier. The PPF of conventional greenhouse was more decreased than the air inflated greenhouse as time went by because the transmittance of conventional greenhouse declined by dust collected on the inside plastic film owing to rolling up and down operation for ventilation.

Depositional Environment and Formation Ages of Eurimji Lake Sediments in Jaechon City, Korea (제천 의림지 호저퇴적물 퇴적환경과 형성시기 고찰)

  • 김주용;양동윤;이진영;김정호;이상헌
    • The Korean Journal of Quaternary Research
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    • v.14 no.1
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    • pp.7-31
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    • 2000
  • Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

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The study for the roles of intratracheally administered histamine in the neutrophil-mediated acute lung injury in rats: (호중구를 매개하는 백서의 급성 폐손상의 병리가전에 있어 기도내로 투여한 히스타민의 역활에 관하여)

  • Koh, Youn-Suck;Hybertson, Brooks M.;Jepson, Eric K.;Kim, Mi-Jung;Lee, In-Chul;Lim, Chae-Man;Lee, Sang-Do;Kim, Dong-Soon;Kim, Won-Dong;Repine, John E.
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.3
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    • pp.308-322
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    • 1996
  • Background : Neutrophils are considered to play critical roles in the development of acute respiratory distress syndrome. Histamine, which is distributed abundantly in lung tissue, increases the rolling of neutrophills via increase of P-selectin expression on the surface of endothelial cells and is known to have some interrelationships with IL-1, IL-8 and TNF-$\alpha$. We studied to investigate the effect of the histamine on the acute lung injury of the rats induced by intratracheal insufflation of TNF-$\alpha$ which has less potency to cause lung injury compared to IL-1 in rats. Methods : We intratracheally instilled saline or TNF(R&D, 500ng), IL-1(R&D, 50ng)or histamine of varius dose(1.1, 11 and $55\;{\mu}g/kg$) with and without TNF separately in Sprague-Dawley rats weighing 270-370 grams. We also intratracheally treated IL-1(50ng) along with histamine($55\;{\mu}g/kg$). In cases, there were synergistic effects induced by histamine on the parameters of TNF-induced acute lung injury, antihistamines(Sigma, mepyramine as a $H_1$ receptor blockade and ranitidine as a $H_2$ receptor blockade, 10 mg/kg in each)were co-administered intravenously to the rats treated TNF along with histamine($1.1\;{\mu}g/kg$) intratraeheally. Then after 5 h we measured lung lavage neutrophil numbers, lavage cytokine-induced neutrophil chemoattractants(CINC), lung myeloperoxidase activity(MPO) and lung leak. We also intratracheally insufflated TNF with/without histamine($11\;{\mu}g/kg$), then after 24 h measured lung leak in rats. Statistical analyses were done by Kruskal-Wallis nonparametric ANOVA test with Dunn's multiple comparison test or by Mann-Whitney U test. Results : We found that rats given TNF, histamine alone(11 and $55\;{\mu}g/kg$), and TNF with histamine(l.1, 11, and $55\;{\mu}g/kg$) intratracheally had increased (p<0.05) lung MPO activity compared with saline-treated control rats. TNF with histamine $11\;{\mu}g/kg$ had increased MPO activity (P=0.0251) compared with TNF-treated rats. TNF and TNF with histamine(1.1, 11, and $55\;{\mu}g/kg$) intratracheally had all increased (p<0.05) lung leak, lavage neutophil numbers and lavage CINC activities compared with saline. TNF with histamine $1.1\;{\mu}g/kg$ had increased (p=0.0367) lavage neutrophil numbers compared with TNF treated rats. But there were no additive effect of histamine with TNF compared with TNF alone in acute lung leak on 5 h and 24 h in rats. Treatment of rats with the $H_1$ and $H_2$ antagonists resulted in inhibitions of lavage neutrophil accumulations and lavage CINC activity elevations elicited by co-treated histamine in TNF-induced acute lung injury intratracheally in rats. We also found that rats given IL-1 along with histamine intratracheally did not have increase in lung leak compared with IL-1 treated rats. Conclusion : Histamine administered intratracheally did not have synergistic effects on TNF-induced acute lung leak inspite of additive effects on increase in MPO activity and lavage neutrophil numbers in rats. These observations suggest that instilling histamine intratracheally would not play synergistic roles in neutrophil-mediated acute lung injury in rats.

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