• Title/Summary/Keyword: complex defects

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The Safety Study on High Tension Bolted Splice by Sliding and Plastic Analysis (고장력볼트 연결부의 미끄럼 및 소성해석에 의한 안전도 연구)

  • Bang, Myung-Seok
    • Journal of the Korean Society of Safety
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    • v.18 no.4
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    • pp.110-114
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    • 2003
  • In this study is proposed the advanced elasto-plastic analytical method which can identify complex structural behaviors on the splice part of steel structures such as sliding and plastic contact problem between splice plates and blots. Compliated boundary conditions and various manufacturing defects are considered in various analytical cases. In the design or repair phase the plastic behavior and ultimate strength of splice parts should be very carefully verified to extend the service life of steel structures.

Numerical and Experimental Study of Semi-solid A356 Aluminum Alloy in Rheo-Forging process

  • Kim, H.H.;Kang, C.G.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.10a
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    • pp.371-374
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    • 2009
  • Die casting process has been used widely for complex automotive products such as the knuckle, arm and etc. Generally, a part fabricated by casting has limited strength due to manufacturing defects by origin such as the dendrite structure and segregation. As an attempt to offer a solution to these problems, forging has been used as an alternative process. However, the forging process provides limited formability for complex shape products. Rheo-forging of metal offers not only superior mechanical strength but also requires significantly lower machine loads than solid forming processes. This paper presents the results of an A356 aluminum alloy sample, which were obtained by experiment and by simulation using DEFORM 3D. Samples of metal parts were subsequently fabricated by using hydraulic press machinery.

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Conservative Treatment of Lymphedema (임파부종 환자의 보존적 치료법)

  • Kim, Sung-Jung;Hwang, Ji-Hye
    • Physical Therapy Korea
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    • v.6 no.1
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    • pp.62-73
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    • 1999
  • The purpose of this article was to provide basic knowledge and treatment principles of patient with lymphedema, which was usually not treated at all, or the treatment given didn't work efficiently. Lmphedema is defined as an abnormal accumulation of protein-rich fluid, edema, and chronic inflammation within an extremity. Lmphedema may be classified as either primary results from defects with aplasia, hypoplasia, and hyperplasia in the lymphatic system at birth or secondary is caused by known precipitating factors such as cancer, infection, inflammation, radiation, surgery, or trauma etc. There are essentially several conservative treatment methods which has been utilized successfully to treat lymphedema in Samsung Medical Center. We used following procedures: CPT (Complex Physical therapy) or CDP (Complex Decongesitive Physical therapy) such as skin care, MLD (Manual Lymph Drainage), compression with short-stretch bandage, exercise, elevation, elastic stocking, and pneumatic compression. Our experiences shows that conservative treatments can significantly reduce lymphedema and prevent different complications.

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c-Cbl Acts as an E3 Ligase Against DDA3 for Spindle Dynamics and Centriole Duplication during Mitosis

  • Gwon, Dasom;Hong, Jihee;Jang, Chang-Young
    • Molecules and Cells
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    • v.42 no.12
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    • pp.840-849
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    • 2019
  • The spatiotemporal mitotic processes are controlled qualitatively by phosphorylation and qualitatively by ubiquitination. Although the SKP1-CUL1-F-box protein (SCF) complex and the anaphase-promoting complex/cyclosome (APC/C) mainly mediate ubiquitin-dependent proteolysis of mitotic regulators, the E3 ligase for a large portion of mitotic proteins has yet to be identified. Here, we report c-Cbl as an E3 ligase that degrades DDA3, a protein involved in spindle dynamics. Depletion of c-Cbl led to increased DDA3 protein levels, resulting in increased recruitment of Kif2a to the mitotic spindle, a concomitant reduction in spindle formation, and chromosome alignment defects. Furthermore, c-Cbl depletion induced centrosome over-duplication and centriole amplification. Therefore, we concluded that c-Cbl controls spindle dynamics and centriole duplication through its E3 ligase activity against DDA3.

Method of simultaneous synthesize for Y123 and Y211 and fabrication of YBCO single crystal (Y123와 Y211분말의 동시 합성과 YBCO 초전도 단결정 제조)

  • 안재원;최희락;한영희;한상철;정년호;성태현
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2002.05a
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    • pp.224-233
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    • 2002
  • A common YBCO powder has been made from a mixture of Y123 and Y211 that heated at different temperatures, respectively. The synthesis temperature of Y211 is lower than Y123. If Y211 has been heated as a synthesis temperature of Y123, a particle size of it may be very coarse. It exist as one of main defects for superconductor. But We simultaneously synthesize a YBCO(its composition is (Y123+0.4Y211)+$lwt%CeO_2$) using polymeric complex method. In the YBCO, the Y123 is synthesized lower temperature than other methodes, and its crystal structure is orthorombic. For measurement of these superconducting properties, we fabricated a YBCO single crystal. The manufactured YBCO single crystal is measured a magnetic distribution device using 0.5Tesla magnet and trapped magnet fields in it are 0.2Tesla.

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Physical Properties of MiDF Cement Composites According to Manufacturing Conditions (제조 조건에 따른 MiDF 시멘트 복합체의 물리적 특성)

  • Park, June Hyoung;La, Jung Min;Kim, Jin Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.138-139
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    • 2021
  • The MiDF Cement Composite is a high-performance construction material with low defects that dehydrates surplus water through pressurization and minimizes air gap between particles. In other words, the performance expression of the MiDF cement complex is affected by pressurized conditions. Thus, this study analyzed the physical characteristics of MiDF cement complex according to the power and pressure of the ga-power and the time of application and intends to use it as a basic data for optimal mixing.

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Functional Expression of Saccharomyces cerevisiae NADH-quinone Oxidoreductase (NDI1) Gene in the AML12 Mouse Liver Hepatocytes for the Applying Embryonic Stem Cell

  • Seo, Byoung-Boo;Park, Hum-Dai
    • Reproductive and Developmental Biology
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    • v.35 no.4
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    • pp.427-434
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    • 2011
  • Mitochondria diseases have been reported to involve structural and functional defects of complex I-V. Especially, many of these diseases are known to be related to dysfunction of mitochondrial proton-translocating NADH-ubiquinone oxidoreductase (complex I). The dysfunction of mitochondria complex I is associated with neurodegenerative disorders, such as Parkinson's disease, Huntington's disease, and Leber's hereditary optic neuropathy (LHON). Mammalian mitochondrial proton-translocating NADH-quinone oxidoreductase (complex I) is largest and consists of at least 46 different subunits. In contrast, the NDI1 gene of Saccharomyces cerevisiae is a single subunit rotenone-insensitive NADH-quinone oxidoreductase that is located on the matrix side of the inner mitochondrial membrane. The Saccharomyces cerevisiae NDI1 gene using a recombinant adeno-associated virus vector (rAAV-NDI1) was successfully expressed in AML12 mouse liver hepatocytes and the NDI1-transduced cells were able to grow in media containing rotenone. In contrast, control cells that did not receive the NDI1 gene failed to survive. The expressed Ndi1 enzyme was recognized to be localized in mitochondria by confocal immunofluorescence microscopic analyses and immunoblotting. Using digitonin-permeabilized cells, it was shown that the NADH oxidase activity of the NDI1-transduced cells was not affected by rotenone which is inhibitor of complex I, but was inhibited by antimycin A. Furthermore, these results indicate that Ndi1 can be functionally expressed in the AML12 mouse liver hepatocytes. It is conceivable that the NDI1 gene is powerful tool for gene therapy of mitochondrial diseases caused by complex I deficiency. In the future, we will attempt to functionally express the NDI1 gene in mouse embryonic stem (mES) cell.

The Wound Healing Effects of Alginate- crosslinked Collagen Dermal Substitute of Artificial Skin (콜라겐을 알긴산으로 교차 결합시킨 인공진피의 창상치유 효과)

  • Chang, Jae Hoon;Park, Dae Hwan;Shin, Jeong Im;Ahn, Ki Young;Song, Chul Hong
    • Archives of Plastic Surgery
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    • v.33 no.1
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    • pp.13-20
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    • 2006
  • Alginate, which is isolated from brown seaweed, is a bioabsorbable long chain polysaccharides, ${\beta}$-D-mannuronic acid and ${\alpha}$-L-guluronic acid. The authors produced alginates and alginate-colllagen as a disc form. Then, to evaluate the efficacy of alginate and alginate-collagen complex as a wound healing material, three full-thickness skin defects of 2 cm in diameter were made at the back of the New Zealand white rabbits. Three groups of dressing materials-alginate, alginate-collagen complex and vaseline gauze as control group - were applied on the wound and the results were evaluated grossly and histopathologically. The authors compared gross findings of sizes of healed wound, wound epithelization and wound contraction by tracing the remaining wound area at 5th, 10th, 15th, 20th, 25th day after wound introduction, and wound biopsy was performed at 3rd, 7th, 14th, 21st day, respectively. Alginate and alginate-collagen complex showed statistically higher percentage of wound contraction and wound healing compared to control group(p<0.05). Alginate-collagen complex showed statistically higher percentage of wound contraction, epithelization and wound healing compared to alginate alone. In conclusion, the result suggests that alginate has a good effect of wound healing and that alginate-collagen complex is more effective in wound healing than alginate alone.

Robust Design for Multiple Quality Attributes in Injection Molded Parts by the TOPSIS and Complex Method (TOPSIS와 콤플렉스법에 의한 사출성형품의 다속성 강건설계)

  • Park, Jong-Cheon;Kim, Gi-Beom;Kim, Gyeong-Mo
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.12
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    • pp.116-123
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    • 2001
  • An automated injection molding design methodology has been developed to optimize multiple quality attributes, which are usually in conflict with each other, in injection molded parts. For the optimization, commercial CAE simulation tools and optimization techniques are integrated into the methodology. To decal with the multiple objective problem the relative closeness computed in TOPSIS(Technique for Order Preference by Similarity to Ideal Solution) is used as a performance measurement index for optimization multiple part defects. To attain robustness against process variation, Taguchi's quadratic loss function is introduced in the TOPSIS. Also, the modified complex method is used as an optimization tool to optimize objective function. The verification of the developed design methodology was carried out on simulation software with an actual model. Applied to production this methodology will be useful to companies in reducing their product development time and enhancing their product quality.

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Excitonic Energy Transfer of Cryptophyte Phycocyanin 645 Complex in Physiological Temperature by Reduced Hierarchical Equation of Motion

  • Lee, Weon-Gyu;Rhee, Young Min
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.858-864
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    • 2014
  • Recently, many researches have shown that even photosynthetic light-harvesting pigment-protein complexes can have quantum coherence in their excitonic energy transfer at cryogenic and physiological temperatures. Because the protein supplies such noisy environment around pigments that conventional wisdom expects very short lived quantum coherence, elucidating the mechanism and searching for an applicability of the coherence have become an interesting topic in both experiment and theory. We have previously studied the quantum coherence of a phycocyanin 645 complex in a marine algae harvesting light system, using Poisson mapping bracket equation (PBME). PBME is one of the applicable methods for solving quantum-classical Liouville equation, for following the dynamics of such pigment-protein complexes. However, it may suffer from many defects mostly from mapping quantum degrees of freedom into classical ones. To make improvements against such defects, benchmarking targets with more accurately described dynamics is highly needed. Here, we fall back to reduced hierarchical equation of motion (HEOM), for such a purpose. Even though HEOM is known to applicable only to simplified system that is coupled to a set of harmonic oscillators, it can provide ultimate accuracy within the regime of quantum-classical description, thus providing perfect benchmark targets for certain systems. We compare the evolution of the density matrix of pigment excited states by HEOM against the PBME results at physiological temperature, and observe more sophisticated changes of density matrix elements from HEOM. In PBME, the population of states with intermediate energies display only monotonically increasing behaviors. Most importantly, PBME suffers a serious issue of wrong population in the long time limit, likely generated by the zero-point energy leaking problem. Future prospects for developments are briefly discussed as a concluding remark.