• Title/Summary/Keyword: Clear zone

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Physiological Characteristics of Actinomycetes Isolated from Turfgrass Rhizosphere (잔디 근권에서 분리된 Actinomycetes균주의 생리학적 특성)

  • Lee, Jung Han;Min, Gyu Young;Shim, Gyu Yul;Jeon, Chang Wook;Kwak, Youn-Sig
    • Weed & Turfgrass Science
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    • v.4 no.4
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    • pp.348-359
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    • 2015
  • Total 443 isolates of actinomycetes were isolated from turfgrass rhizosphere as potential biological control agents. The two isolates (S11 and S4) showed highest cellulase activity with compared to the other isolates that exhibited a clear zone of 1.2 mm around the colony on cellulose agar medium. S12 strain appeared the most active chitin degrading, which exhibited a 1.2 mm of clear zone. The highest proteolytic activity on skim milk agar was which exhibited a 7.5 mm of clear zone by S2 strain. S1 strain from the soli showed siderophore production ability, which exhibited a 0.6 mm of large clear zone on chrome azurol S agar. The antifungal activity of the volatile compound producing by 4 selected actinomycetes was investigated that inhibition rate against Rhizoctonia solani AG2-2 and Sclerotinia homoeocarpa. Growth inhibition effect of S8 isolate against S. homoeocarpa was appeared to 94.8%, S2 to 76.9%, S5 to 46.1% and S12 to 43.5%. The significant inhibition effects on mycelial growth of S. homoeocarpa were shown on media with four strains. The inhibition effect was the highest with S8 strain treatment at 94.8%.

Isolation and Identification of Antimicrobial Compound from Jakyak(Paeonia japonica var. pilosa N$_{AKAI}$ (백작약으로부터 식품부패 미생물에 대한 항균성 물질의 분리 및 동정)

  • 황재선;전희정;한영실
    • Korean journal of food and cookery science
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    • v.16 no.5
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    • pp.445-452
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    • 2000
  • Antimicrobial activity of Jakyak(Paeonia japonica var. pilosa $N_{AKAI}$) was investigated. Methanol extract of dried Jakyak was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as B. subtilis, L. monocytogenes, and V. parahaemolyticus at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 11 fractions by silica gel column and thin layer chromatography(TLC). The results showed that ethylacetate fractions No. 3, 4 and 5 had the highest antimicrobial activity. They were mixed again, re-separated, and 5 fractions were obtained. Among them, the highest inhibitory effect was obtained in No. 3 fraction, which was identified as cetyl alcohol by HPLC and GC-MS.S.

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A Study on the Threshold of Avoidance Sector in the New Evaluation of Collision Risk

  • Jeong Tae-Gweon
    • Journal of Navigation and Port Research
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    • v.28 no.9
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    • pp.799-802
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    • 2004
  • Evaluation of the quantitative risk of collision plays a key role in developing the expert system of navigation and collision avoidance. This study analysed thoroughly how to determine the threshold of avoidance sector as described in the new evaluation of collision risk, and suggested the collision risk obtained by the alteration of course and/or speed in order to pass clear qf each danger zone as the threshold of avoidance sector.

아트리움 공간에 있어서 화재에 의한 연기 유동에 관한 수치해석적 연구

  • 노재성;유홍선;정연태
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 1997.11a
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    • pp.43-48
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    • 1997
  • The smoke filling process for the atrium space containing a fire source is simulated using two types of deterministic fire modus: Zone model and Field model. The zone mode used is the CFAST(version 1.6) mode developed at the Building and Fire Research laboratories, NIST in the USA. The lied model is a self-developed fire field model based on Computational Fluid Dynamics(CFD) theories. This article is focused on finding out the smoke movement and temperature distribution in atrium space which is cubic in shape. A computational procedure for predicting velocity and temperature distribution in fro-induced flow is based on the solution, in finite volume method and non-staggered grid system, of 3-dimensional equations for the conservation of mass, momentum, energy, species and so forth. The fire model i. e. Zone model and Field model predicted similar results for Ire clear height and the smoke layer temperature.

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Waterfront Development Project Pattern Analysis of the Coastal Zone Management of the Osaka Bay

  • Yang, Jae-Joon;Yhang, Wii-Joo
    • Journal of Navigation and Port Research
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    • v.27 no.3
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    • pp.329-333
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    • 2003
  • Study of the background and state of Osaka's waterfront space development and analysis of the functions of 22 chosen major facilities of development project reveals the following four types: amenity-oriented development, large-scale synthesis type development, renewal compound area type development, exchange communication promotion type development. Osaka bay area has served primely as the base of harbors, industry and energy, while analysis of the ongoing project has found that the city has been making a functional transition to a type of development to live up to the needs of the times, suggesting that is wise that Korea's future direction of waterfront development be oriented toward environmental-friendly development by taking advantage of low-density area's natural resources. Given the plurality and complexity of the law of coastal zone, what is needed is a legal maintenance for coastal zone's clear-cut coordinating function and for environmental-friendly development with the limitations of seaside and coastal functions in mind.

A Study on the Condensation and Thermal Environment according to Window Systems Types Installed for a Extended-Balcony Apartment (확장형 발코니 공동주택의 창호종류에 따른 결로 및 온열환경에 관한 연구)

  • Yoon, Jong-Ho;An, Young-Sub;Kim, Byoung-Soo
    • KIEAE Journal
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    • v.7 no.5
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    • pp.87-92
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    • 2007
  • As expansion of balconies at apartments has been legalized, the major function of the balconies as a thermal buffer zone is disappearing. This weakens the ability of window to insulate heat and multiplies surface condensation. Thus more and more residents require solutions to increasing surface condensation and aggravation in thermal comfort. This study intends to provide basic data by evaluating performance of triple layered Low-E windows, triple layered clear windows, double layered Low-E windows and double layered clear window used for expanded balconies and marketed within the country in terms of surface condensation and thermal environment through simulation. Results revealed that no surface condensation occurred at double layered Low-E windows and triple layered Low-E windows. Surface condensation took place at double layered clear windows and triple layered clear windows at a relative humidity of 60%. Thermal environment analysis suggested that double layered clear windows showed the most time falling into the range of comfort at $23^{\circ}C$. The figure were $22^{\circ}C$ for triple layered clear windows, $22^{\circ}C$ for double layered Low-E windows and $21^{\circ}C$ for triple layered Low-E windows.

AN ELECTRON MICROSCOPIC STUDY ON THE ALVEOLAR BONE REMODELLING IN PRESSURE ZONES OF RAT MOLAR PERIODONTIUM ASSOCIATED WITH ORTHODONTIC TOOTH MOVEMENT (백서구치의 교정적 치아이동중 압박측 치조골의 골개조에 관한 연구)

  • Soun, Yo Sun;Lee, Ki Soo
    • The korean journal of orthodontics
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    • v.19 no.2
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    • pp.37-55
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    • 1989
  • The tissue reactions concerned in alveolar bone remodelling at the pressure zones of rat molar periodontium associated with the application of force (15 gm) to the maxillary first molar teeth of the albino rats were studied by the transmission electron microscopy. Osteoclasts referrable to bone resorption were observed thereafter 3 hour survival period and undermining resorption was generated thenceforth 2 day survival period. Bone resorption, reversal zone and new bone formation were simultaneously observed adjacent to the zone of undermining resorption in the 7 day survival period. Osteoclasts with well developed primary lysosome, ruffled border, clear zone, granules and Golgi apparatus were detected at the zone of the bone resorption, and dark and bright cells adjacent to the osteoclasts as well. Mononuclear cells and perpendicularly arranged collagenous fibers were observed in the reversal zone and, on the other hand, osteoblasts with well developed Golgi apparatus and rough endoplasmic reticulum were detected at the zone of bone formation.

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Antimicrobial, Antihypertensive and Anticancer Activities of Garlic Extracts (마늘 추출물의 항균, 항고혈압 및 항암활성)

  • Kim, Ki-Ju;Do, Jeong-Ryong;Kim, Hyun-Ku
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.228-232
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    • 2005
  • Antibacterial, antifungal, anticancer, and ACE inhibitory activities of methanol, ethyl acetate, chloroform, and hexane extracts of garlic were investigated. Methanol extract showed highest yield of 7.9-8.8 brix. Ethyl acetate and chloroform extracts showed strong antibacterial activities as determined by inhibition zone (8-16mm) against B. subtilis and P. aeruginosa, and good antifungal activities as determined by inhibition zone (8-30mm) against A. niger, M. miehei, and T. reesei. Wando, Banyans, Chinese, and Seosan garlic methanol extracts showed 65.6, 60.4, 70.1, and 55.3% ACE inhibitory activities, 42.3, 53.8, 50.4, and 54.5% anticancer activities against SNU-1, and 11.3, 20.2, 36.6, and 30.5% anticancer activities against HeLa, respectively.

An Analysis of Riparian Vegetation Distribution Based on Physical Soil Characteristics and Soil Moisture Content -Focused on the Relationship between Soil Characteristics and Vegetation- (토양의 물리적 특성 및 수분조건에 다른 하반식물의 분포 -토양환경과 식생과의 관계를 중심으로-)

  • 안홍규
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.5
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    • pp.39-47
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    • 2000
  • This study is to investigate the conditions closely related to the establishment of vegetation in the riparian zone: the soil condition, an important factor along with climate and light. Especially, the soil structure of the microtopographical formations in the specific area known as the riparian microtopographical zone investigated. In addition, the effect of the riparian microtopographical features on the ground water level, soil moisture content, and vegetation was studied. The results of this study are as follows; 1) At all sample sites, below the sand layer, a gravel layer is always present. This is the result of past floods. 2) Although Salix koreensis experiences frequent disturbances such as increase in river level and floods, this vegetation establishes itself in the most secure are in the microtopographical zone. 3) The growth of Phragmites japonica is closely related to the underground water level. 4) It is clear that Miscanthus sacchariflorus grows concentrated in dry areas. 5) The soil accumulation conditions differ according to the soil moisture content of each microtopgraphical feature. Accordingly, the moisture content of the soil is clearly different within the microtopographical zone. The continuous and long-term investigation and research on the relation of riparian reproduction and the relevance with location surrounding factors are necessary in the future.

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Effect of Temperature on Fatigue Resistance of Crack Repaired zone by Injecting Epoxy Resin (에폭시 수지를 이용한 균열보수부의 내피로성능에 미치는 온도의 영향)

  • Shin, Hong-Chol
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.527-528
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    • 2009
  • Effects of temperature on fatigue resistance of crack zone in concrete members repaired by injecting epoxy resin was experimentally studied. First, a fatigue machine that produces small movement similar to those observed in actual cracks was developed. It was made clear that the rise of temperature changes a mode of fracture at the repaired zone and sharply dropped fatigue resistance.

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