• 제목/요약/키워드: LAM

검색결과 816건 처리시간 0.022초

CO2 레이저 보조가공에 의한 세라믹재료의 가공성에 관한 기초 연구 (The Basic Study on Machinability of Ceramics in CO2 Laser Assisted Machining)

  • 김종도;이수진;박서정
    • Journal of Advanced Marine Engineering and Technology
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    • 제33권2호
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    • pp.322-329
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    • 2009
  • Machinability of LAM(Laser Assisted Machining) has been studied for ceramics such as $Al_2O_3$, $Si_3_N4$ and $ZrO_2$ by $CO_2$ laser. It was possible to remove ceramics by PCBN tool because material became softening and deterioration by local laser beam irradiation. The advantage of LAM is the ability to produce larger material removal rates and tool life. But, for cutting of $Al_2O_3$ and $ZrO_2$, stage of laser power control was needed owing to thermal shock with high temperature of workpiece by laser power. And when $Si_3N_4$ was machined by LAM, $N_2$ gas spouted from surface of one cause of high temperature. Characteristics of LAM were analyzed using pyrometer, dynamometer, SEM and EDS to measure temperature of workpiece surface, cutting force, variation of machining surface and structure of lattice respectively. As the result of this study, it was found that machinability of LAM for ceramics in $CO_2$ laser and mechanism of LAM was different according to the kind of ceramics because of properties of materials.

Inhibition Effect of Gleditsia Sinensis Lam on T tyrosinase Activity and Reactive Oxygen Species related to Melanin Biosynthesis

  • Kim, Yeon-Zu;Kim, Jin;Park, Hee-Jung;Lee, Chang-Moon;Lee, Ki-Young
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVI)
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    • pp.541-543
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    • 2005
  • 조협은 trosinase 저해 활성 실험 결과 1.9%(w/v) 이상의 농도에서 70%이상의 저해를 나타내고, UV 흡수능에서는 220-230nm 에서 최대 흡수 파장이 나타나고 250-550nm 에서 고르게 흡수되는 경향을 보인다. 조협은 자외선 차단효과와 활성산소종 형성 억제 및 멜라닌 생성을 저해함으로써 피부미백 효과에 기여한다. 따라서 조협을 이용한 liposome을 제조하여 미백화장품에의 응용 가능성을 높여 줄 수 있다.

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Crystallization and X-ray crystallographic analysis of the PH-like domain of lipid transfer protein anchored at membrane contact sites from Saccharomyces cerevisiae

  • Tong, Junsen;Im, Young Jun
    • Biodesign
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    • 제5권4호
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    • pp.136-140
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    • 2017
  • Lam6 is a member of sterol-specific ${\underline{l}ipid$ transfer proteins ${\underline{a}}nchored$ at ${\underline{m}ebrane$ contact sites (LAMs). Lam6 localizes to the ER-mitochondria contact sites by its PH-like domain and the C-terminal transmembrane helix. Here, we purified and crystallized the Lam6 PH-like domain from Saccharomyces cerevisiae. To aid crystallization of the Lam6 PH-like domain, T4 lysozyme was fused to the N-terminus of the Lam6 PH-like domain with a short dipeptide linker, GlySer. The fusion protein was crystallized under the condition of 0.1 M HEPES-HCl pH 7.0, 10% (w/v) PEG 8000, and 0.1 M $Na_3$ Citrate at 293K. X-ray diffraction data of the crystals were collected to $2.4{\AA}$ resolution using synchrotron radiation. The crystals belong to the orthorhombic space group $P2_12_12_1$ with unit cell parameters $a=59.5{\AA}$, $b=60.1{\AA}$, and $c=105.6{\AA}$. The asymmetric unit contains one T4L-Lam6 molecule with a solvent content of 58.7%. The initial attempt to solve the structure by molecular replacement using the T4 lysozyme structure was successful.

결핵성 흉막염 환자에 있어서 효소결합 면역분석법으로 측정한 Purified-Protein-Derivative와 Lipoarabinomannan-B에 대한 Immunoglobulin G 항체의 진단적 가치에 관한 연구 (Immunoglobin G Antibodies to Purified-Protein-Derivative and Lipoarabinomannan-B by Enzyme-Linked Immunosorbent Assay in the Diagnosis of Tuberculous Pleural Effusion)

  • 문태훈;조철호;곽승민;김진주;조상래
    • Tuberculosis and Respiratory Diseases
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    • 제42권4호
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    • pp.455-464
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    • 1995
  • 연구배경: 인체의 결핵균 감염에 대하여 체액성 면역과 세포 매개성 면역이 함께 관여하며 효소결합 면역 분석법으로 결핵균 항원에 대한 항체(IgG)를 측정하는 것은 결핵성 흉막염 진단법으로 이용할 수 있다. 방법: 1992년 5월부터 1994년 7월까지 인하대학교 인하병원에 흉막염으로 입원하였던 환자 중 원인이 확진된 결핵성 흉막염 환자 40예, 비결핵성 흉막염 환자 19예를 대상으로 하여 혈청 및 흉막액에서 PPD 항원과 LAM-B 항원에 대한 IgG 항체가의 흡광도를 측정 하였다. 결과: 1) 결핵성 흉막염군의 흉막액 및 혈청내 PPD와 LAM-B 항체가는 비결핵성 흉악염군보다 유의하게 높았다.(p<0.0005) 2) 혈청내 PPD와 LAM-B 항체가는 흉막액내 항체가 보다 높았다. 3) PPD와 LAM-B에 대한 흉막액 항체와 혈청 항체간에는 의미있는 상관관계를 보였다. 4) 흉막액 PPD 항체의 결핵성 흉막염 진단기준을 0.091로 할 경우 진단적 예민도는 55.0%, 94.7%를 나타내었다. 5) 흉막액 LAM-B 항체의 결핵성 흉막염 진단기준을 0.337로 할 경우 진단적 예민도는 50.0%, 특이도는 94.7%를 나타내었다. 5)결핵성 흉막염군의 진단 양성률은 PPD 피부반응 검사, 흉막액의 양, 활동성 폐결핵 동반여부 등에 의해 영향받지 않았다. 결론: PPD와 LAM-B에 대한 IgG 측정은 결핵성 흉막염의 진단에 도움을 줄 것으로 사료된다. 아울러 PPD와 LAM-B에 대한 IgG는 수동적으로 흉막조직을 통해 혈청에서 흉막액으로 이동함을 제시하고 있다.

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Frequency Characteristics of Spiral Planar Inductor without Underpass for LAM Process (LAM 공정을 위한 Underpass를 갖지 않는 나선형 박막 인덕터의 주파수 특성)

  • 김재욱
    • 전기전자학회논문지
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    • 제12권3호
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    • pp.138-143
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    • 2008
  • 본 논문에서 기존 반도체공정들이 갖는 리소그래피와 식각 등의 공정단계를 배제하는 direct-write 공정과 LAM(Laser Ablation of Microparticles) 공정을 이용하여 친환경적인 이점을 가질 수 있는 나선형 인덕터의 구조를 제안하고 주파수 특성을 확인하였다. 인덕터의 구조는 Si를 540${\mu}m$, $SiO_2$를 3${\mu}m$으로 하였으며, Cu 코일의 폭과 선간의 간격은 LAM 공정과 direct-write 공정을 이용할 수 있도록 각각 30${\mu}m$으로 설정하여 2회 권선하였다. 나선형 박막 인덕터의 성능을 나타내는 인덕턴스, quality-factor, SRF에 대한 주파수 특성을 HFSS로 시뮬레이션 하였다. Underpass와 via가 제거된 인덕터는 300-800MHz 범위에서 1.11nH의 인덕턴스, 5GHz에서 최대 38 정도의 품질계수를 가지며, SRF는 18GHz로 시뮬레이션 결과를 얻었다. 반면에 underpass와 via를 가지는 일반적인 인덕터는 300-800MHz 범위에서 1.12nH의 인덕턴스, 5GHz에서 최대 35 정도의 품질계수를 가지며, SRF는 16GHz로 시뮬레이션 결과를 얻을 수 있었다.

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미세먼지로 유도된 기관지염증에 다시마가 함유된 복합물의 효과 (Effects of Nature Herb Mixture Containing Laminaria japonica Areschoung on Fine Dust-induced Bronchitis in Mice)

  • 한수현;주인환;이수빈;김동희;현주명;박종민
    • 동의생리병리학회지
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    • 제34권5호
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    • pp.245-254
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    • 2020
  • The purpose of this study was to investigate the effects of natural herb mixture containing Laminaria japonica Areschoung (LAM) on fine dust-induced bronchitis in mice. Laminaria japonica Areschoung is main content of LAM, which is including fucoidan. Fucoidan extracted from phaophyta is known to prevent bronchitis and to defend against bacteria and virus infection. In this study, we experienced the effect of LAM on bronchitis and investigated gene expressions (e.g ; IL-8, COX-2, MCP-1) and bio-markers (e.g ; IL-8, PGE2, MUC5AC) associated with bronchitis by using A549 cells. Also, we investigated whether LAM can suppress the bronchitis in fine dust-induced animal models. We injected fine dust (50 ㎕) twice as INT (Intra-Nasal-Trachea) method. Then LAM (200 mg/kg and 400 mg/kg) were oral administered for 14 days. We analyzed the number of immune cells, immunoglobulin E, bio-markers level associated with bronchitis. LAM significantly decreased bio-marker (IL-1β, IL-6, IL-8, TNF-α, Histamine, PGE2), immune cells (white blood cell, neutrophil, lymphocyte, monocyte), and immunoglobulin E, that are increased by fine dust. Taken together, this study suggest that LAM can be used as effective herbal extract for bronchitis.

Evaluation of Antioxidant Activity and Cytotoxicity in Mixture Extract of Artemisia asiatica Nakai and Moringa oleifera Lam

  • Lee, Yoon-Ji;Kim, Jang-Oh;Jeon, Chan-Hee;Lee, Ji-Eun;Shin, Ji-Hye;Min, Byung-In
    • 대한의생명과학회지
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    • 제26권4호
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    • pp.296-301
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    • 2020
  • The purpose of this study was performed to evaluate antioxidant activity of the Artemisia asiatica Nakai and Moringa oleifera Lam mixture extract. Mixture extracts were manufactured by concentration and compared with a single extract (only the Artemisia asiatica Nakai mixture and only the Moringa oleifera Lam mixture). The experiments conducted Total polyphenol measurements, Total flavonoid measurements, DPPH radical scavenging activty, ABTS radical scavenging activty and LDH assay. The LDH assay assessment shows that all extracts are cells compared to controls. The toxicity was weak. Finally, The antioxidant capacity was rated higher than mixture extract of a single extract. Also, the optimized mixture was determined AM5 (Artemisia asiatica Nakai mixture: Moringa oleifera Lam mixture = 3:1). For extracts of AM5, Total phenol and flavonoid contents were 271.769±18.087 mg/g and 45.384±5.026 mg/g. and DPPH and ABTS scavenging activity were 70.8±6.496% and 77.1±9.634%. Therefore, it is expected that the value of the extract will increase as it increases its antioxidant activity if it is manufactured according to the appropriate ratio.

LAM 가공조건에 따른 열-구조 연성해석 (A Study on the Thermo-Mechanical Coupling Analysis to Working Condition of LAM)

  • 박정호;박성호;김귀남
    • 한국산업융합학회 논문집
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    • 제25권6_3호
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    • pp.1127-1133
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    • 2022
  • Recently, the use of aircraft structures using Ti alloy (Ti-6Al-4V), a lightweight high-strength alloy material, is rapidly increasing due to the weight reduction of aircraft. However, high-strength materials such as Ti alloys require high energy for cutting and are classified as difficult-to-cut materials. Also, research on Laser Assisted Machining (hereinafter referred to as LAM), a cutting processing technology that utilizes improved machinability, is being actively researched. Therefore, in this paper, in order to confirm the proper temperature distribution using a laser, the finite element method is used to determine the temperature distribution according to the calorific value condition to derive the appropriate condition, and the thermal load generated at this time is used as a structural analysis. It is intended to be used as basic data for LAM processing conditions by measuring the amount of residual stress and thermal deformation caused by heat.

SOFM과 LAM을 이용한 영상 보간에 관한 연구 (A Study on Image Interpolation Using SOFM and LAM)

  • 장동언;정태상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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    • pp.640-642
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    • 1998
  • When resampling an image to a new set of coordinates, there is often a noticeable loss in image quality. The interpolation kernel determines the quality of interpolation. In this paper, We think two interpolation methods: cubic-spline method, neural net method, at first study given interpolation method using spline and then present new interpolation methon using SOFM and LAM(neural net method), finally compare the performance of several interpolation methods including replication, bilinear, spline and new methods.

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