• Title/Summary/Keyword: 재성장

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A Fire Test Measuring the Heat Release Rate of Railway Car Interior Materials Satisfying the Korean Safety Guideline (안전기준을 만족하는 철도차량 내장재의 화재 열방출율 측정시험)

  • Park, Won-Hee;Lee, Duck-Hee;Jung, Woo-Sung
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.40-49
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    • 2009
  • A large-scale fire test was conducted for interior materials from a vehicle installed within a fire test room (ISO 9705). The interior materials are satisfying the Korean guideline for the safety of rail vehicles, where the guideline has taken effect since December 2004 in Korea. The output of ignition source (gas burner) was increased in several controlled steps. The objectives of this test are to assess the fire performance in terms of ignition and flame spread on interior lining materials and to provide data on an enclosure fires involving train interior materials that grow to flashover. These data will be used to develop and calibrate models for fire growth on the interiors of the railway vehicle.

금속의 피로 및 피로균열전파

  • Kim, Sang-Sik
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.22.1-22.1
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    • 2011
  • 산업의 발달과 더불어 수송기기를 포함한 각종 구조물의 경량화에 따라 피로파괴에 대한 관심이 높아지고 있다. 과거에는 피로균열생성과 피로균열전파를 구분하지 않는 S-N (stress-cycles to failure) 피로 개념을 이용하여 구조재의 피로 거동을 이해하고자 하였다. 그러나 최근에는 모든 구조물에는 균열이 존재한다는 가정에서 시작된 파괴역학(fracture mechanics)에 기초한 피로균열성장 개념을 이용하여 피로에 대한 저항성이 큰 구조재를 개발하고 있으며, 구조물의 피로수명을 예측하고 있다. 본 발표에서는 미세조직, 인장특성, 용접이나 부식 환경 등이 금속의 피로 및 피로균열성장(fatigue crack propagation)에 미치는 영향에 대한 논하고자 한다.

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인터뷰 - 최민수 (주)팩플러스 대표이사

  • Jo, Na-Ri
    • The monthly packaging world
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    • s.339
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    • pp.106-108
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    • 2021
  • 최근 기업은 환경을 보호하고 사회적 가치를 중요하게 여기며 투명하고 윤리적인 지배구조 개선을 실천해야만 지속성장할 수 있다는 'ESG경영'이 화제가 되고 있다. ESG는 기업이 얼마나 돈을 잘 버는지가 아니라 어떻게 돈을 벌고, 어떻게 쓰는지를 중요시 하는 것이다. ESG라는 말이 나오기 전부터 환경과 사회적 가치를 실현하며 성장하고 있는 포장기업이 있다. 경기도 광주시에 위치한 연포장 전문기업 (주)팩플러스이다. 지난 6월 23일 연포장재기업 최초로 LOHAS 인증을 취득하고, 알코올타입 그라비어인쇄기를 도입해 친환경 포장재를 생산하고 있는 팩플러스를 찾아 최민수 대표이사와 함께 포장기업의 ESG경영에 대한 이야기를 나눠보았다.

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Quality Characteristic of Breads added Herb Extracts and Liquid Calcium (한약재 및 액상칼슘을 첨가한 제빵의 품질 특성)

  • Kim, Ok-Mi;Woo, Hong;Kim, Kyung-Eun;Woo, Seung-Mi;Jung, Yong-Jin
    • Food Industry And Nutrition
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    • v.7 no.3
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    • pp.39-43
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    • 2002
  • 본 연구에서는 전통적으로 한방에서 성장 촉진을 위하여 사용된 녹각, 우슬, 구기자, 두충, 오미자 및 용안 등의 한약재 추출물과 액상칼슘을 각각 첨가하여 4구간의 빵을 제조하여 품질 특성을 비교 분석하였다. 빵의 물성을 측정한 결과, strength, hardness는 한약재 추출물과 액상칼슘의 첨가량이 많을수록 높아지는 경향을 나타냈었으며 cohesiveness, springiness, gumminess 및 brittleness는 감소하는 경향으로 나타났다. 빵의 내부와 표면의 색도(L,a,b)는 첨가량에 따라 차이가 있었으며 저장 4일째에 각각 변화 정도의 차이가 있었다. $37^{\circ}$ 에서 4일간 저장 후 일반세균은 무첨가구 $15\times10^3CFU/g$에 비하여 한약재 추출물 및 액상칼슘 첨가량이 많은 구간에서는 급격히 감소하여 보존성이 높게 나타났다. 관능적 특성은 실험구간에 따른 유의적 차이는 크게 나타나지 않았으며, 각각의 실험구간에 따른 칼슘함량을 비교 분석한 결과. 한약재 추출물과 액상칼슘이 많은 구간에서 높게 나타나는 경향이었다. 이상의 결과를 바탕으로 성장촉진 한약재 및 액상칼슘을 기능성 소재로서 제빵에 활용 가능할 것으로 생각된다.

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Impact of Turbidity on Protected Plants along River Levees (탁수가 하천 제방보호 식물에 미치는 영향 분석)

  • Kim, Jong-Tae;Kim, Eun-Jin;Kang, Joon-Gu;Yeo, Hong-Koo
    • The Journal of Engineering Geology
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    • v.23 no.2
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    • pp.161-170
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    • 2013
  • We analyzed the effect of changing water level and turbidity on plants that serve to maintain slope stability on levees. In this experiment, soil collected from upstream of Imha Dam was placed in a water tank and planted with river plants of the Salix species: Salix gracilistyla, S. koreensis, and S. glanduosa. Plant regrowth was analyzed stage-by-stage during a recovery period. In addition, we assessed the tolerance of the plants to concentrated torrential rainfall and examined their recovery rates. The results indicate that in the case of these three Salix species, which are the most prevalent river plants in Korea, stem growth is arrested following serious damage and high turbidity. The possibility of regrowth was very low during the 20-day non-submerged recovery period. Although the number of leaves initially decreased during this period, subsequent regrowth was reasonably high: recovery in S. gracilistyla, S. koreensis, and S. glanduosa was up to 59.3%, 251.3%, and 148.4% respectively, compared with the initial condition.

Antimicrobial Activities of Medicinal Herb Extracts (한약재추출물의 항균활성)

  • Chang, Hyung-Soo;Choi, Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.2
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    • pp.261-269
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    • 2012
  • In this study, 18 kinds of Korean medicinal herb extracts were examined for anti-microbial activities against pathogenic microorganisms. The methanol (MeOH) extracts from Schizandra chinensis, Rhus javanica and Caesalpinia sappan exhibited antimicrobial activities against most pathogenic microorganisms at concentrations of 5 mg/mL, whereas the other 15 extracts exhibited anti-microbial activities at concentrations of 30 mg/mL. The minimum concentration at which Schizandra chinensis extracts inhibited for S. epidermidis and Bor. bronchiseptica was 0.6 mg/mL. The MeOH extracts from Schizandra chinensis, Caesalpinia sappan, Rhus javanica and Seutellaria baicalensis which had higher anti-microbial activities were subsequently fractionated using 5 different solvents, and further screened for anti-microbial activities. The inhibitory effects of ethyl acetate (EtOAc) extracts on microbial growth were greater compared to any other solvent extracts. In order to investigate the inhibitory effect of Korean medicinal herbs with high anti-microbial activities on microbial proliferation, the MeOH extracts at concentrations of 0, 100, 300 and 500 ppm were added to the media. No addition of extracts caused rapid growth of microbes after 12 hours incubation. As the concentration of extracts from Rhus javanica and Caesalpinia sappan increased, the growth-inhibiting effect on gram-positive bacteria including S. aureus, S. epidermidis, and L. monocytogenes was prominent. Rhus javanica extracts exhibited growth-inhibiting activity for gram-negative bacteria including Sal. Pullorum and Sal. Choleraesuis. The low concentration of extracts from Rhus javanica and Caesalpinia sappan exhibited the growth of Bor. bronchiseptica and E. coli serotype $O_8$. However, the higher concentration of extracts from Rhus javanica and Caesalpinia sappan exhibited a strong inhibitory effect on microbial proliferation.

Investigation of the Growth Rate Change in Recombinant BCG which was cloned Mycobacterium tuberculosis Adenylate Kinase Mutation Gene or Human Muscle-type Adenylate Kinase Synthetic Gene (결핵균 Adenylate Kinase 돌연변이 유전자와 Human Muscle-type Adenylate Kinase 합성 유전자를 형질전환한 BCG의 성장속도 변화 유무 조사)

  • Lee, Seung-Heon;Kim, Hyo-Joon;Park, Young-Kil;Bai, Gill-Han
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.2
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    • pp.187-193
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    • 2006
  • Background : Normal cell proliferation and viability is strongly depends on the availability of metabolic energy and the maintenance of the appropriate adenylate-nucleotide pools. Hypothetically, changes in adenylate kinase (AK) expression could therefore be associated with adaptation to altered growth characteristics or inversely altered growth characteristics of proliferating cells could drive the changes in the metabolic profile. This study investigated whether the expression of either AK1 or a Mycobacterium tuberculosis adenylate kinase mutant which has the same catalytic activity of AK1 could affect the growth rate of slow-growing BCG. Method : Recombinant BCGs, which were cloned the human muscle-type adenylate kinase synthetic gene (AK1) and adenylate kinase mutation gene (AKmtDM) of Mycobacterium tuberculosis into the Mycobacterium/E.coli expression vectors, were constructed. Recombinant BCGs and wild-type BCG were cultured in 7H9 media and the optical density at 600nm was measured at intervals of 2-3 days. Result : There wasn't the growth rate change induced by AK1 or AKmtDM expression in recombinant BCGs. Conclusion : The expression of AK1 or Mycobacterium tuberculosis adenylate kinase mutant in BCG does not affect the growth rate of BCG.