• Title/Summary/Keyword: 한국 제4기학회

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The Effect of Focal Length on Fuel Mixing And Combustion in One-focusing Oxygen Burner (일 초점 산소 버너의 초점 거리가 연료 혼합 및 연소에 미치는 영향)

  • Park, Kweon-Ha;Kim, Ju-Youn
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.6
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    • pp.814-819
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    • 2011
  • An Oxy-fuel combustion has been studied in order to reduce exhaust emissions and fuel consumption. The flow and flame behaviors are analyzed with focal length variation in one-focussing oxygen burner introduced in this study. Oxygen is supplied into the center of the nozzle, methane fuel is into the outer nozzle of the center, and then oxygen is again supplied into the outer of the fuel nozzle. The test conditions are 5 focal lengths of 100mm to 500mm. The mixing behaviors and temperature distributions are analyzed. The result shows that the shorter the focal length is, the longer the mixing length becomes, and the flame width and length are the biggest in the case of 300mm.

Structural Development of Polypropylene Foam by Crosslinking and Processing Conditions (가교도와 공정 조건에 따른 폴리프로필렌 발포체 구조 변화)

  • 황대영;한갑동;홍다윗;이규일;이기윤
    • Polymer(Korea)
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    • v.24 no.4
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    • pp.529-537
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    • 2000
  • The effects of the gel content on the cell structures of PP sheets by using an electron-curing system were investigated. Three extruded PP sheets crosslinked by three different doses were used for the batch foaming process with the supercritical state $CO_2$. Experiments were also performed in order to study the effects of the gel content, saturation pressure and temperature on cell structures. Then foaming conditions, such as temperature and duration of time, were changed. The amount of gas absorbed into PP samples was not affected by gel contents and the operating condition of saturation pressure, which was higher than 2000 psi. The foam cells of PP with a low gel content grew irregularly at a higher foaming temperature and for a longer duration of foaming time. However, PP samples with high gel content showed even cell structures and narrow tell size distributions under the severe conditions of high foaming temperatures and long duration of foaming time.

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A Study on the Classification for Technology Convergence according to Characteristics (기술융합 특성에 따른 새로운 분류체계의 제안)

  • Hwang, Da-Young;Kim, Young-In;Lee, Byung-Min
    • Journal of Korea Technology Innovation Society
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    • v.11 no.4
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    • pp.592-612
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    • 2008
  • The convergence of technology as a major breakthrough in technology innovation has been generated and developed. With the advent of the 21st century characterized by the knowledge-based economy, it is happening even more frequently and vigorously than ever. However, study on classification system or definition of notions is necessary as the convergence of technology is still in the early stage. The existing classification system has limited application to the convergence of technology. With no standard available for the classification of the technology convergence, there has been much concern for duplicative R&D investment. On this ground, a new and reformed classification system for the convergence of technology and definition of notions are needed. Previous studies regard base technologies used in the technology convergence and new convergence technologies as important. However, this paper views convergence of technology as a dynamic phenomenon and puts an emphasis on the cause of technology convergence, not on the new technology itself and examines whether base technologies go back to their original state after the completion of technology convergence. This kind of approach will classify technology convergence by characteristics. Although more researches including quantitative analysis are necessary, this paper expects to offer help with further researches on classification system.

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Zinc and Copper Status of Middle- and Old-Aged Women in Type 2 Diabetes (중.노년기 제2형 당뇨병 여성의 아연 및 구리 영양상태)

  • Lee Jung Hee;Lee Hee Ja;Lee In Kyu;Yoon Jin Sook
    • Journal of Nutrition and Health
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    • v.38 no.1
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    • pp.56-66
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    • 2005
  • The purpose of this study was to assess the zinc and copper status of type 2 diabetic women and to analyse the relation-ship among zinc and copper status, and diabetic control indices of diabetes. The mean age of diabetes was 57.9 years old. The mean duration of diabetes was 8.0 $\pm$ 6.5 years. The mean daily energy intake of diabetes was 1562 kcal. There were no significant differences of age, BMI, %body fat, nutritional intakes, total energy intake, and energy composition from carbohydrate, protein, and fat between diabetes (n = 50) and control group (n = 68). However, both zinc intake density (4.15 mg/1000 kcal) and zinc %RDA (62.0%) of diabetes were significantly lower than control group (p <0.05, P < 0.01, respectively). The plasma zinc level was not significantly different between diabetes and control group (90$\mu$g/dl, 91$\mu$g/dl respectively). The proportion of diabetic women whose plasma zinc levels were lower than 76 $\mu$g/dl(borderline zinc deficiency) was 18.8%. This was about 38% higher than control group. It has been suggested that insulin secretion might decrease in borderline plasma zinc and copper deficiency and increase in normal plasma zinc and copper status. The urinary zinc excretion was twice higher in diabetes than in control group (p < 0.001). The urinary zinc loss was positively correlated with the duration of diabetes (p < 0.05), hyperglycemia (p < 0.001) and insulin resistance (p < 0.05). These results lead us to conclude that normal blood glucose level controlled by diet therapy could improve the hyperzincuria in diabetic women.

Mathematical analysis on the effect of mineral nutrients on the growth rate of Chlorella (Chlorella의 성장에 미치는 무기영양의 영향에 관한 반응속도론적 연구)

  • 장남기
    • Korean Journal of Microbiology
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    • v.7 no.3
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    • pp.107-114
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    • 1969
  • Relationship of soil properties and seasonal variation on microbilogical population to-continuous culture and first-time culture of ginseng was investigated by bimonthly from May 1976 to January 1977. pH and P contents of 2 years continuous culture of soil were higher than other culture plot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was conplot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was contained more potassium contents than other culture plot of soil. In microbiological fluctuation with seasonr in various soil conditions, the population, trends of Fusarium spp., Erwiniaspp., and flourescent Psedudomonas spp. were increased in May and July in general, but decreased in the other month. It was observed that in all type of soil, Fusarium spp. was distributed in abundance in and on rihizosphere, and decreased the propagules numbers as soil depth increase. The numbers of Erwinia spp. and fluorescent Pseudo-monas spp. were distributed greater in numbers on the surface zone of soil depth decreasing the numbers along the soil layer increase, and also in 2years continuous culture of soil especially, a great numbers of Erwinia spp. and fluorescent Pseudomonas were evenly distributed in surface zone and rhizosphere. Ginseng disease with a high incidence of bacterial disease in continuous culture of 2 and 4 years was seemed to be associated with soil bacteria that was high in numbers of Erwinia spp. and fluorescent Pseudomonas spp. in May and July.

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Law of the Sea Problems on Fishery Resources Conservation and Management in the Yellow Sea and East China Sea (황해(黃海)와 동중국해어장(東中國海漁場)의 수산자원(水産資源) 보존관리(保存管理)에 관한 해양법문제(海洋法問題))

  • Lee, Byoung-Gee;Choe, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.6 no.1
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    • pp.77-91
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    • 1994
  • The Yellow Sea and the East China Sea are the most important fishing grounds for the fishing industry of Korea, China and Japan which are major coastal states of these Seas. But the fishery resources in these fishing grounds are almost exhausted and also the sea region is seriously polluted. Accordingly an international joint countermeasure is necessary to recover the fishery resources and to keep the fishery a continuous industry. The authors inspected the existing fishery policies and international fishery relationship of the three coastal states, and suggested rational conservation and management regime of the fishery resources in these sea regions. 1. At present the legal status of the sea region beyond territorial sea is the high sea, for that reason the international cooperation is urgently needed to establish common regime for conservation and management of the fishery resources. 2. A series of scientific research on ecological system of fishery resources must be carried out in the sea region first of all for that purpose. 3. The existing Korea-Japanese Fishery Agreement and Sino-Japanese Fishery Agreement should be reformed to coincide with the new legal order of the UNLOS Convention, and the Sino-Korean Fishery Agreement should be concluded newly on the identical line. 4. As a conclusion, a joint conservation and management regime through a regional fishery organization or a individual conservation and management regime through the promulgation of exclusive economic zone by each state can be suggested to resolve the fishery resources conservation problem in the Yellow Sea and the East China Sea.

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Radiological Environment Investigation of Radioactive Waste Disposal Facility (방사성폐기물 처분시설 주변의 방사선환경조사)

  • Baek, Jeong-Seok;Jeong, Yeui-Young;Ahn, Sang-Bok;Kim, Wan
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.387-398
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    • 2008
  • To obtain base-line data in the low- and intermediate-level radioactive waste disposal facility, radiological environment investigation is required at least two years prior to the facility operation near the disposal facility. The investigation has been performed since January 2007 for the Wolsong LILW disposal center. In this paper, investigation procedure and detailed information obtained for six months in 2008 are described. Based on the current results, future investigation planning is also discussed for the radiological environment management of the disposal facility.

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Isolation and Some Cultural Characteristics of ${\delta}-Aminolevulinic$ Acid - Producing Photosynthetic Bacteria (${\delta}-Aminolevulinic$ Acid 생산 광합성세균의 분리 및 배양특성)

  • Cheong, Dae-Yeol;Choi, Yang-Mun;Yang, Han-Chul;Cho, Hong-Yon
    • Applied Biological Chemistry
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    • v.40 no.6
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    • pp.561-566
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    • 1997
  • Screening, Identification and some cultural characteristics of ALA$({\delta}-aminolevulinic\;acid)$-producing photosynthetic bacteria were carried out for the optimal production of ALA, one of the bioherbicides. Among photosynthetic bacteria isolated from soil, marsh, pond, etc., KK-10 was the best producer of ALA and identified to be Rhodobacter capsulatus belonging to a typical group of nonsulfur purple bacteria. By addition of 15 mM LA (levulinic acid), an inhibitor of ALA dehydrase in cyclic tetrapyrrole biosynthesis, into culture broth at middle log phase of cell growths, ALA production was considerably increased to about 20-fold (28 mg/l). The combined supplementation of glycine and succinate, each with a concentration of 30 mM also enhanced production of ALA and activity of ALA synthase to about 50-fold (73 mg/l) and 2-fold, respectively. The isolated strain was able to produce upto 80 mg/l under the cultural condition optimized by addition 15 mM LA into the synthetic medium at four different points starting middle log phase.

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The Systematic Form Generation of Product Design (제품디자인의 체계적 형태발상 연구)

  • 이문기
    • Archives of design research
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    • v.15 no.1
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    • pp.279-288
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    • 2002
  • The appearance of Internet, the 5th medium which has succeeded newspaper, magazine, TV, radio, creates WEB MAGAZINE to overcome the restriction of space and time. This paper has conducted the contents and visual points of view in webmagazine. Through case study, the following and identify for the analysis of the webmagazine contents and visual format. Firstly, communiation at webmagazine is carried out at the user-centered atmosphere. Secondly, Even through an aesthetic is emphasized in the webmagazine, when web designer compose of the web site, it is necessary to find the proper methodology under the basis of users behavior Thirdly, Although webmagazine required the visual form, we should know that the evaluation of webmagazine should be implemented by users. Therefore, webmagazine should be designed by the user-centered layout.

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Octimization of Score Production via Sonication of Antifungal Polyene-producing Actinomycetes (초음파 파쇄에 의한 항진균 폴리엔 생성 방선균의 포자형성 최적화)

  • Kim, Byung-Kyun;Han, Kyu-Beom;Kim, Eung-Soo
    • KSBB Journal
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    • v.22 no.4
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    • pp.218-221
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    • 2007
  • The polyene antifungal antibiotics, mostly produced by Gram-positive soil actinomycetes, are a family of type I polyketide macrolide ring compounds with 20$\sim$40 carbon backbone contain 3$\sim$8 conjugated double bonds. Using polyene-specific genomic screening strategy, we previously isolated three novel polyene-producing actinomycetes strains from soil, implying the potential application of these strains' spores as microbial pesticides. Here, we report that the sonication is a very efficient method for actinomycetes spore generation with a sonicator power-dependent manner. In addition, these sonication-driven actinomycetes spores retained significant portion of their cell viabilities as well as antifungal activities after freeze-drying procedure, implying the potential application of these strains' spores as microbial pesticides.