• Title/Summary/Keyword: action modes

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Analysis for Cold Die Compaction of Meteal Powder (금속분말의 냉간금형 압축 해석)

  • Gwon, Yeong-Sam;Lee, Hui-Tae;Kim, Gi-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.6
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    • pp.1893-1902
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    • 1996
  • Densification behavior of 316L stainless steel power under die pressing was studied. The efects of friction between the powder and die wall under different die pressing modes were also investigated. The elastoplastic constitutive equations based on the yield functions of Fleck-Gurson and of Shima and Oyane were implemented into finite element program(ABAQUS) to simulate die compaction processes. The finite element results were compared with experimental data for 316L stainless steel powder under die pressing.

Downregulation of fungal cytochrome c peroxidase expression by antifungal quinonemethide triterpenoids

  • Seo, Woo-Duck;Lee, Dong-Yeol;Park, Ki Hun;Kim, Jin-Hyo
    • Journal of Applied Biological Chemistry
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    • v.59 no.4
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    • pp.281-284
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    • 2016
  • To handle the development of antifungal drug resistance, the development of new structural modules and new modes of action for antifungals have been highlighted recently. Here, the antifungal activity of quinonemethidal triterpenoids such as celastrol, dihydrocelastrol, iguestein, pristimerin, and tingenone isolated from Tripterygium regelii were identified (MIC $0.269-19.0{\mu}M$). C. glabrata was the most susceptible to quinonemethide among the tested fungi. Furthermore, quinonemethide suppressed cyctochrome c peroxidase expression dramatically, decreasing fungal viability caused by the accumulation of hydrogen peroxide. Thus, cyctochrome c peroxidase downregulation of quinonemethide may be a key mode of action for antifungals.

Seismic Performance Analysis of RC Subway Station Structures (철근콘크리트 지하철 정거장 구조물의 내진 성능 해석)

  • 남상혁;송하원;변근주
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.123-128
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    • 2002
  • In this paper, an averaged constitutive model of concrete and reinforcing bars for RC structure and path-dependent Ohsaki's model for soil are applied, and an elasto-plastic interface model having thickness is preposed for seismic analysis of underground RC subway station structure. A finite element analysis technique is developed by applying aforementioned constitutive equations and verified through seismic analysis of underground RC subway station. Then, failure mechanisms of the RC subway station structure under seismic action are numerically derived. Then, failure modes and damage levels of the station are also analytically evaluated for the cases of several designs of the underground RC station.

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Adjuvants-a classification and review of their modes of action (Adjuvant-그 분류 및 작용방법에 대한 개관)

  • Cox John C.;Coulter Alan R.
    • Journal of the korean veterinary medical association
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    • v.33 no.11
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    • pp.683-691
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    • 1997
  • 금세기초부터 갖가지 물질이 vaccine에 가해졌으며, 일정한 처방이 vaccine을 더욱 유효하게 만들기 위해서 고안되고 있다. 많은 선택권에도 불구하고 다만 aluminium 염(鹽)만이 사람용 vaccine adjuvant(면역응답강화물질)로 받아들여지고 있으며, 수의(동물)용 vaccine도 크게 aluminium 염의 사용에 의존하고 있다. 현재 많은 새로운 vaccine들이 개발되고 있으나 vaccine당 구성분의 수를 증가시키고 또한 vaccine 과정에서 요구되는 dose 수를 줄이는 vaccine 접종 schedule을 단순화시키고져 하는 욕구가 대두되고 있다. 이제 더욱 유효한 adjuvant들이 이 욕구를 성취시키기 위해서 요구되는 것이다.

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Molecular Aspects of Some Photobiological Receptors

  • Song, Pill-Soon
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.10-25
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    • 1977
  • The photobiological receptors of phototactic, phototropic, and photomorphogenic responses of various organisms have been described in terms of spectroscopic, photophysical and photochemical properties which may be relevant in elucidating the energy transduct ion mechanism(s) in photobiology. The photoreceptors discussed include carotenoids, flavins, stentorin and phytochrome. Although the molecular modes of their photobiological action still remain largely unexplained, it is possible to suggest several primary molecul ar processes of the photoreceptors in eliciting responses of various organisms to light.

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Luis Bunuel and Naturalist Cinema (루이스 브뉴엘과 자연주의 영화)

  • Kim, Jung-Ho
    • The Journal of the Korea Contents Association
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    • v.22 no.10
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    • pp.181-194
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    • 2022
  • between the Action-image and the Affection-image, there is the Impulse-image. IF the aesthetics of the action-image and Affection-image are realism and idealism, the aesthetics of the impulse - image is naturalism. since the impulse-image has traits of action-image and affection-image, naturalism refers to four co-ordinates: originary world/derived milieu, impulses/modes of behavior. In Deleuze's view, the great directors we call naturalists are Stroheim, Bunuel, and Joseph Losey.

Different modes of antibiotic action of homodimeric and monomeric bactenecin, a cathelicidin-derived antibacterial peptide

  • Lee, Ju-Yeon;Yang, Sung-Tae;Kim, Hyo-Jeong;Lee, Seung-Kyu;Jung, Hyun-Ho;Shin, Song-Yub;Kim, Jae-Il
    • BMB Reports
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    • v.42 no.9
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    • pp.586-592
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    • 2009
  • The bactenecin is an antibacterial peptide with an intramolecular disulfide bond. We recently found that homodimeric bactenecin exhibits more potent antibacterial activity than the monomeric form and retains its activity at physiological conditions. Here we assess the difference in the modes of antibiotic action of homodimeric and monomeric bactenecins. Both monomeric and dimeric bactenecins almost completely killed both Staphylococcus aureus and E. coli within 10-30 min at concentrations of $8-16\;{\mu}M$. However, exposure to liposomes elicited an increase in the fluorescence quantum yield from a tryptophan-containing monomeric analog, while the homodimeric analog showed a significant reduction in fluorescence intensity. Moreover, unlike the monomer, the homodimer displayed apparent membrane-lytic activity enabling release of various sized dyes from liposomes, and rapidly and fully depolarized the S. aureus membrane. Together, our results suggest that homodimeric bactenecin forms pores in the bacterial membrane, while monomeric one penetrates through the membrane to target intracellular molecules/organelles.

Antimicrobial Characteristic of Prunus mune extract (매실추출물의 항균특성)

  • Ha Myung-Hee;Park Woo-Po;Lee Seung-Cheol;Choi Sung-Gil;Cho Sung-Hwan
    • Food Science and Preservation
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    • v.13 no.2
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    • pp.198-203
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    • 2006
  • Prunus mume extract showed antimicrobial efface remarkably against the wide spectrum of putrefactive and food spoilage microorganisms above 250 ppm of concentration. Their thermal and pH stabilities were effective under the range of temperature $(40^{\circ}C{\sim}120^{\circ}C)$ and $pH(3{\sim}11)$. Prunus mume extract seemed to be a natural antimicrobial ideally with the view of their effectiveness and thermal & pH stabilities. In addition, their action modes suggested that their hydrophillic components would perturb the fucntions of microbial cell membranes synergistically.

Progressive failure of symmetrically laminated plates under uni-axial compression

  • Singh, S.B.;Kumar, Ashwini;Iyengar, N.G.R.
    • Structural Engineering and Mechanics
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    • v.5 no.4
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    • pp.433-450
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    • 1997
  • The objective of this work is to predict the failure loads, associated maximum transverse displacements, locations and the modes of failure, including the onset of delamination, of thin, flat, square symmetric laminates under the action of uni-axial compression. Two progressive failure analyses, one using Hashin criterion and the other using Tensor polynomial criteria, are used in conjunction with the finite element method. First order shear deformation theory and geometric nonlinearity in the von Karman sense have been employed. Five different types of lay-up sequence are considered for laminates with all edges simply supported. In addition, two boundary conditions, one with all edges fixed and other with mixed boundary conditions for $(+45/-45/0/90)_{2s}$ quasi-isotropic laminate have also been considered to study the effect of boundary restraints on the failure loads and the corresponding modes of failure. A comparison of linear and nonlinear results is also made for $({\pm}45/0/90)_{2s}$ quasi-isotropic laminate. It is observed that the maximum difference between the failure loads predicted by various criteria depend strongly on the laminate lay-ups and the flexural boundary restraints. Laminates with clamped edges are found to be more susceptible to failure due to the transverse shear and delamination, while those with the simply supported edges undergo total collapse at a load slightly higher than the fiber failure load.

Risk Evaluation Based on the Hierarchical Time Delay Model in FMEA (FMEA에서 계층적 시간 지연 모형에 근거한 위험평가)

  • Jang, Hyeon Ae;Lee, Min Koo;Hong, Sung Hoon;Kwon, Hyuck Moo
    • Journal of Korean Society for Quality Management
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    • v.44 no.2
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    • pp.373-388
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    • 2016
  • Purpose: This paper suggests a hierarchical time delay model to evaluate failure risks in FMEA(failure modes and effects analysis). In place of the conventional RPN(risk priority number), a more reasonable and objective risk metric is proposed under hierarchical failure cause structure considering time delay between a failure mode and its causes. Methods: The structure of failure modes and their corresponding causes are analyzed together with the time gaps between occurrences of causes and failures. Assuming the severity of a failure depends on the length of the delayed time for corrective action, a severity model is developed. Using the expected severity, a risk priority metric is defined. Results: For linear and quadratic types of severity, nice forms of expected severity are derived and a meaningful metric for risk evaluation is defined. Conclusion: The suggested REM(risk evaluation metric) provides a more reasonable and objective risk measure than the conventional RPN for FMEA.