• Biomedical Science Letters
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• v.15 no.1
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• pp.67-72
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• 2009

Microtubule-interfering agents (MIAs), including paclitaxel, have been attributed in part to interference with microtubule assembly, impairment of mitosis, and changes in cytoskeleton. But the signaling mechanisms that link microtubule disarray to destructive or protective cellular responses are poorly understood. This study investigated the effect of paclitaxel on differentiation such as type II collagen expression and sulfated proteoglycan accumulation in rabbit articular chondrocytes. Paclitaxel caused differentiated chondrocyte phenotype as demonstrated by increment of type II collagen expression and proteoglycan synthesis Paclitaxel treatment stimulated activation of ERK-1/2 and p38 kinase. Inhibition of ERK-1/2 with PD98059 enhanced paclitaxel-induced differentiation, whereas inhibition of p38 kinase with SB203580 suppressed paclitaxel-induced differentiation. Our findings suggest that ERK-1/2 and p38 kinase oppositely regulate paclitaxel-induced differentiation in chondrocytes.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.12-16
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• 2022

Di-tyrosine photo-crosslinking of silk fibroin (SF) is recently highlighted as a biocompatible hydrogel fabrication process, because this method does not need potentially harmful chemical species. However, the resulting crosslinking density is often insufficient to obtain a mechanically stiff hydrogel unless additional oxygen is provided during the reaction. In this study, we proposed a combinational crosslinking method to form an SF hydrogel via the di-tyrosine photo-crosslinking with riboflavin (photoinitiator) and physical interaction of SF chains. In the UV light-irradiated SF solution, small particles formed and these particles promoted β-sheet formation of SF molecules, resulting in quick gelation. The di-tyrosine photo-crosslinking produced nuclei that might trigger regular assembly of SF molecules in high temperature condition. Conclusively, this process would contribute to a development of biocompatible hydrogel fabrication for biomedical uses of SF hydrogels.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.43-43
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• 2003

EST analysis was performed to identify stress-responsive and immune-related genes from rock bream (Oplegnathus fasciatus). cDNA libraries were constructed with liver and randomly chosen 624 clones were subjected to automated sequence analysis. Of 624 clones sequenced in total, approximately 15% of ESTs was novel sequences (no match to GenBank) or sequences with high homology to hypothetical/unknown genes. The bioinforamtic sequence analysis including functional clustering, homology grouping, contig assembly with electronic northern and organism matches were carried out. Several potential stress-responsive biomarker and/or immune-related genes were identified in all the tissues examined. It included lectins, ferritins, CP450, proteinase, proteinase inhibitors, anti-oxidant enzymes, various heat-shock proteins, warm temperature acclimation protein, complements, methyltransferase, zinc finger proteins, lysozymes, macrophage maturation associated protein, and others. This information will offer new possibilities as fundamental baseline data for understanding and addressing their molecular mechanism involved in host defense and immune systems of this species.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.38-44
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• 2011

Remanufacturing is restoring or manufacturing the worn-out or discarded components of an end of life product in order to bring it to the "like new" condition. The aim is to reprocess used products in such a manner that the quality of the products is as good as or better than the new one, in terms of appearance, reliability and performance. This paper investigates the automotive remanufacturing industry in Europe. To further knowledge in this field, the paper focuses on the remanufacturing of the automotive components of end-of-life vehicles. The paper scope emphasizes key remanufacturing companies, which are identified and were surveyed in terms of their business structures. The research aims to address the potential for growth within the remanufacturing industry, with regard to various players. The state of the art in remanufacturing of automotive equipment will be identified.

• Journal of the Korean Society for information Management
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• v.34 no.1
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• pp.317-340
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• 2017

Non-ideological information exchange and cooperation based on the scholarly and cultural fields would be the most effective project of south and north Korea for gaining the national homogeneity and trust in the long-term perspective. In this context, this study researched the measures on cultural exchange and cooperation between south and north through national libraries for the unified Korea. Related with that issue, this study analyzed function and limitation of national library in north Korea and evaluated library cooperation between south and north Korea in the frame of cultural cooperation project. So, this study suggested the stepwise model of the library cooperation between south and north based on the five practical measures including the cooperation governance system.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.53.1-53.1
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• 2014

The M81 group is a nearby galaxy group hosted by M81, a twin galaxy of Milky Way. This galaxy group is considered as an ideal laboratory for near-field cosmology to understand mass assembly and evolution of galaxies in the group environment. We designed a project to investigate spectroscopic properties of globular cluster candidates in this group. We obtained spectra of globular cluster candidates using the MMT/Hectospec as a part of the K-GMT Science Program. Our main targets include globular cluster candidates of the M81 group member galaxies and those wandering in the intragroup region. We also observed supernova remnants and some background galaxies. Observing fields covered about 2 square degrees including three main galaxies of the M81 group. Using these spectra, we will identify globular clusters in the M81 group, and investigate their properties including age and metallicity. We will discuss the MMT/Hectospec data reduction processes, and future plan for this project.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.213-213
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• 2010

In this thesis, we studied to increased to solar conversion efficiency of DSSC (dye-sensitized solar cell) using nanocrystalline $TiO_2$ semiconductor. We are preparation of $TiO_2$ photoelectrode, assembly the DSSC and put a focus in analyses electrochemical properties of DSSC and using Silica powder in $TiO_2$ photoelectrode for increase light scattering effect and improved conversion efficiency. It attempt to investigate the morphology of the photoelectrode and photovoltaic effects using field emission scanning electron microscopy (FE-SEM) and photovoltaic properties under illumination with AM 1.5 simulated sunlight. We got 146 % enhanced power conversion efficiency when the optimal content of quartz glass powder was 5 wt.% than that another content.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.9
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• pp.707-714
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• 2016

This paper describes analysis results of vibration characteristics and modal test for a small-scale quad-rotor drone. The rotor arm has a slender body with a propeller and motor at its tip. Rotor system generates excitation for an unbalanced mass. Therefore, the drone platform is involved in the possibility of resonance. For advance identification of the possibility of resonance, confirmation of eigen-mode being closest to the propeller operation range is necessary. Material properties of CFRP tubes used for the rotor arm were acquired by finding the natural frequency based on Rayleigh method. A simplified quad-rotor FE model consisting of rotor arm assembly with tip mass was built to perform numerical analysis, and a free-free boundary condition was applied to provide flight status. Modal tests for the actual platform with impact hammer instrument were performed to verify analysis results. Separation margin from hazardous eigen-mode was checked on the propeller operation range.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.8
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• pp.80-85
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• 2021

This study is to evaluate the structural stability of heavy duty structure of the Complex CNC automatic lathe. The analysis conditions were analyzed by applying the weight and load of the part itself and then applying the weight of the upper assembly unit. As a result of the structural analysis, the values of stress and strain are small and safety factor is high, and as a result of the dynamic analysis, there will be no resonance outside the equipment driving area, so there will be no problem in equipment stability.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.11a
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• pp.72-75
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• 2020

조립 부품 이미지에 해당하는 3D CAD 모델 매칭 기술은 최근 로봇 조립 기술의 발전으로 필요성이 대두되고 있다. 이미지 기반 3 차원 모델 매칭 연구는 진행되어 왔지만 가구 부품 이미지와는 특성이 다른 RGB[5] 이미지나 스케치 이미지를 다루는[1] 접근들이었다. 딥러닝을 사용하는 스케치 이미지 기반 3 차원 물제 검색 연구에서는 대부분 3 차원 이미지를 다각도에서 렌더링한 view 이미지들에서 feature를 추출하고 pooling 하여 하나의 feature를 출력한다. 그러나 기존의 view pooling 방식은 단순한 평균 방식으로, 부품 이미지에 따른 view를 반영하기에는 한계가 있었다. 따라서 본 논문에서는 조립 부품 이미지 기반 3 차원 물체 검색을 위해 query 부품 이미지에 따라 다른 view 이미지에 집중할 수 있는 방식의 attentional view pooling을 제안한다. 또한 조립 부품 데이터의 특성 상 class 당 CAD 모델이 하나인 상황이므로 학습 데이터가 터무니없이 부족하여 이를 해결하기 위한 학습 데이터 증강 방법을 제안한다. 실험은 의자 부품 11가지에 대해 진행하였고 이를 통해 제안하는 방식의 성능을 입증하였다.