• 제목/요약/키워드: T74

검색결과 2,013건 처리시간 0.033초

On uniform asymptotic stability of the nonlinear differential system

  • 오영선;안정향
    • 한국산업정보학회논문지
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    • 제9권4호
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    • pp.68-74
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    • 2004
  • We investigate various $\phi(t)-stability$ of comparison differential equations and We obtain necessary and/or sufficient conditions for the asymptotic and uniform asymptotic stability of the differential equations x'=f( t, x)

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육성비육돈의 분뇨배설량 및 이화학적특성 (Characteristics and Quantity of Waste Produced by Crowing and Finishing Pig)

  • 곽정훈;강희설;최희철;최동윤;전병수;한정대;김태일;김형호
    • 한국축산시설환경학회지
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    • 제7권3호
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    • pp.165-168
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    • 2001
  • 육성비육돈의 분뇨배설량 및 분뇨특성을 조사한 결과 시험기간중 사료섭취량은 3.07 kg/일.두, 음수량은 3.84kg/일.두였으며, 평균 분뇨 배설량은 각각 1.80kg/일.두, 2.76kg/일 .두로 총 4.57kg의 분뇨를 배설하는 것으로 조사되었다. 이화학적 특성에서 돈분의 수분 함량은 74.1%, pH 6.5, 질소 0.89%, $P_2O_5$ 0.46%였으며, BOD 및 SS는 각각 74,224m/l, 261,089mg/l였다. 돈뇨의 경우에는 수분 98.2%, pH 7.5, 질소 0.83%, P$_2$O$_{5}$ 0.05% 였으며, BOD 및 SS는 각각 6,054mg/l, 453mg/l였다.

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국산 프로폴리스의 플라보노이드 조성에 관한 연구 (Studies on the Flavonoid Compositions of Korean Propolis)

  • 이수원;김희재;양희진;황보식
    • 한국축산식품학회지
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    • 제21권4호
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    • pp.389-394
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    • 2001
  • 본 연구는 벌집에서 얻어지는 프로폴리스의 플라보노이드 함유량을 조사하였다. UV spectrophotometer를 이용한 총플라보노이드는 예천, 영월, 브라질, 호주, 중국이 각각 6.33, 6.42, 2.44, 8.11, 6.52mg/g이었다. HPLC를 이용한 플라보노이드 분석 결과, p-courmaric acid는 예천, 5.58, 그리고 영월이 6.84mg/100g 이었다. 그러나 예천 및 영월의 프로폴리스에서는 luteolin이 검출되지 않았다. Quercetin은 영월, 예천에서 0.41∼0.53%이었으며, t-cinnamic acid는 브라질이 7.92%, quercitrin은 중국이 8.74%로 가장 높았다. 또한 중국산 프로폴리스에서는 t-cinnamic acid가 검출되지 않았다.

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7175Al 링롤단조재의 미세조직과 기계적 성질에 미치는 공정조건의 영향 (Effect of Process Conditions on the Microstructure and Mechanical Properties of 7175Al Ring Roll Forgings)

  • 이인기;강락경;이오연
    • 열처리공학회지
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    • 제17권1호
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    • pp.10-16
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    • 2004
  • The aim of this study is to investigate the process conditions on the microstructual changes and mechanical properties of large 7175 aluminum ring roll forgings. The billets range from 370 mm to 720 mm in diameter were homogenized and ring roll forged after direct chill casting. The tensile properties of ring roll forged specimen manufactured with ${\Phi}370mm$ billets were superior to those of ${\Phi}720mm$ billets under $T_6$ condition. Also, these properties showed better than those of military specification under $T_{74}$ treatment. The impact value of ring roll forged specimen under $T_{74}$ treatment increased up to 20% than that of $T_6$ condition. The fracture toughness of ring roll forged specimen manufactured with ${\Phi}370mm$ cast billet showed nearly same level of ${\Phi}720mm$ billet which was processed using MF or Cog free forging followed by ring roll forging.

The Anti-Wrinkle Mechanism of Ganoderma lucidum mycelial with Acorus gramineus callus in UVB Treated HaCaT Keratinocytes

  • Eun-Sil Ko;Sang-Min Cho;Sol Lee;Ji-Hye Jung;Jea-Ran Kang;Jong-Hoon Jeong;Dong-gue Shin;Jeong Hun Seo;Jeong-Dan Cha
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2020년도 춘계학술대회
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    • pp.74-74
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    • 2020
  • Skin is continuously exposed to a variety of environmental stresses, including ultraviolet (UV) radiation. UVB is an inherent component of sunlight that crosses the epidermis and reaches the upper dermis, leading to increased oxidative stress, activation of inflammatory response and accumulation of DNA damage among other effects. In the present study, the anti-wrinkle mechanism of Acorus gramineus callus culture supernatant (GB-AGS-PSC) was elucidated in UVB treated HaCaT keratinocytes. GB-AGS-PSC prevented the matrix metalloprotease 1 (MMP-1), elastin, and pro-collagen product and cytotoxicity and SOD inhibition. Quantitative polymerase chain reaction showed that GB-AGS-PSC-treated cells displayed dose-dependent increase in messenger RNA expression levels of Aquaporin 3 (AQP3), Keratin 1(KRT1), fillagrin, and hyaluronan synthase-2 (HAS 2) and decreased expression levels of matrix metalloproteinase-3, -9, and -13 in UVB treated HaCaT keratinocytes. Additionally, GB-AGS-PSC suppressed TNF-α, IL-1β, and IL-8 product for inflammatory responses in UVB treated HaCaT keratinocytes. Therefore, GB-AGS-PSC may be useful as an anti-photoaging resource for the skin.

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