• Title/Summary/Keyword: Mechanism factor

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Design Walking System Based on Theo Jansen Mechanism (얀센 메커니즘 기반의 보행 기구 설계)

  • Lee, Hyeonkyeong;Yun, Yungkyu
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.404-410
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    • 2016
  • Compared to wheel locomotion, walking has many advantages : Better to cross over obstacles, the contact with ground is in a determined point, the ground is damaged less. Because Theo Jansen mechanism can make walking motion that is very soft, there are many researches about that mechanism. In this paper, We designed walking robot based on Theo Jansen mechanism. Most important design factor is velocity and stability. First of all, we considered kinematics knowledge and then, we made a new model by using simulation. Finally we developed the model by solving few design problems.

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Action Mechanism of Chamaecyparis obtusa Oil on Hair Growth

  • Park, Young-Ok;Kim, Su-Eun;Kim, Young-Chul
    • Toxicological Research
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    • v.29 no.4
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    • pp.241-247
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    • 2013
  • This study was carried out to examine the action mechanism of Chamaecyparis obtusa oil (CO) on hair growth in C57BL/6 mice. For alkaline phosphatase (ALP) and ${\gamma}$-glutamyl transpeptidase (${\gamma}$-GT) activities in the skin tissue, at week 4, the 3% minoxidil (MXD) and 3% CO treatment groups showed an ALP activity that was significantly higher by 85% (p < 0.001) and 48% (p < 0.05) and an ${\gamma}$-GT activity that was significantly higher by 294% (p < 0.01) and 254% (p < 0.05) respectively, as compared to the saline (SA) treatment group. For insulin-like growth factor-1 (IGF-1) mRNA expression in the skin tissue, at week 4, the MXD and CO groups showed a significantly higher expression by 204% (p < 0.05) and 426% (p < 0.01) respectively, as compared to the SA group. At week 4, vascular endothelial growth factor (VEGF) expression in the MXD and CO groups showed a significantly higher expression by 74% and 96% (p < 0.05) respectively, however, epidermal growth factor (EGF) expression in the MXD and CO groups showed a significantly lower expression by 66% and 61% (p < 0.05) respectively, as compared to the SA group. Stem cell factor (SCF) expression in the MXD and CO groups was observed by immunohis-tochemistry as significant in a part of the bulge around the hair follicle and in a part of the basal layer of the epidermis. Taking all the results together, on the basis of effects on ALP and ${\gamma}$-GT activity, and the expression of IGF-1, VEGF and SCF, which are related to the promotion of hair growth, it can be concluded that CO induced a proliferation and division of hair follicle cells and maintained the anagen phase. Because EGF expression was decreased significantly, CO could delay the transition to the catagen phase.

Inhibitory Mechanism of Blood Coagulation by the Anticoagulant Polysaccharide from Coriolus versicolor (구름버섯 기원 항응고성 다당류의 혈액응고 저해기작)

  • Lee, Hyun-Sun;Kweon, Mee-Hyang;Lim, Wang-Jin;Sung, Ha-Chin;Yang, Han-Chul
    • Korean Journal of Food Science and Technology
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    • v.29 no.4
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    • pp.817-822
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    • 1997
  • Inhibitory mechanism of the anticoagulant polysaccharide purified from the fruit body of Coriolus versicolor was investigated in this paper. The anticoagulant polysaccharide (CV-40-Va-1) was proposed to have functions of the inhibition of intrinsic pathway in the blood coagulation pathway together with the interuption of a human platelet aggregation induced by von Willebrand factor (vWF). CV-40-Va-I inhibited other factors of the coagulation cascade such as factor VIII, IX, and as well as thrombin. Especially, CV-40-Va-I inhibited the fibrin formation mediated by thromin, however the polysaccharide did not affect the fibrin formation directly but affected the anticoagulant activity through the activation of antithrombin III. The sulfation of the anticoagulant polysaccharide increased the anticoagulant activity, showing that the sulfate concentration of anticoagulant polysaccharide was important factor in the blood coagulation cascade. Low molecular weight subfraction (MW 1,000) obtained by partial hydrolysis of the CV-40-Va-1 generated potent antiplatelet activity, but showed decreased anticoagulant activity.

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Estrogen receptor is downregulated by expression of HIF-1a/VP16

  • Cho, Jung-Yoon;Lee, Young-Joo
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.228.2-229
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    • 2003
  • Estrogen Receptor is a ligand-activated transcription factor. The concentration of the receptor is a major component that regulates expression of estrogen-responsive genes. We have studied mechanism of estrogen receptor alpha (ER${\alpha}$) downregulation by HIF-1 using HIF-1${\alpha}$/VP16 constructs. ER${\alpha}$ is known to be downregulated under hypoxic condition. Transcriptional response under hypoxia is mediated through Hypoxia-inducible factor-1 (HIF-1), a transcription factor that is usullaly degraded but stabilized under hypoxia. (omitted)

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Study of hepatoprotective effect of Haegan-jeon through activation of nuclear factor erythroid 2-related factor 2 and optimization of herbal composition based on molecular mechanism (Nuclear factor erythroid 2-related factor 2 활성화를 통한 해간전(解肝煎)의 간세포 보호 효능 및 분자기전을 활용한 해간전(解肝煎) 구성 약물의 최적화 연구)

  • Kim, Jae Kwang;Jung, Ji Yun;Park, Sang Mi;Park, Chung A;Ku, Sae Kwang;Byun, Sung Hui;Cho, Il Je;Kim, Sang Chan
    • Herbal Formula Science
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    • v.26 no.3
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    • pp.207-221
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    • 2018
  • Objectives : Present study investigated hepatoprotective effect of Haegan-jeon extract (HE) and tried to elucidate molecular mechanism involved. According to molecular mechanism, present study optimized herbal composition of HE (op-HE) and compared in vitro and in vivo hepatoprotective effects of op-HE to HE. Methods : For in vitro experiments, HepG2 cells were exposed to arachidonic acid (AA, $10{\mu}M$) and iron ($5{\mu}M$) for inducing oxidative stress. Cell viability, GSH contents, $H_2O_2$ production, mitochondrial membrane potential, immunoblot and reporter gene assay were performed to investigate cytoprotective effects and responsible molecular mechanisms. For in vivo experiments, hepatoprotective effect of HE and op-HE were assessed on $CCl_4-induced$ liver injury mice model. Results : HE pretreatment prevented AA+iron-mediated hepatocytes apoptosis. In addition, AA+iron-induced mitochondrial dysfunction, $H_2O_2$ production, glutathione depletion were reduced by HE pretreatment. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation, antioxidant response element (ARE)-driven reporter gene activity, and antioxidant genes expression were increased by HE. Based on reporter gene and MTT assays, we found that op-HE consisting three medicinal herbs also significantly increased transactivation of Nrf2 and reduced the AA+iron-mediated cytotoxicity. Moreover, in $CCl_4-induced$ liver injury mice model, HE-op had an ability to ameliorate $CCl_4-mediated$ increases in serum alanine transferase and aspartate aminotransferase activity, hepatic degeneration, inflammatory cell infiltration, and collagen deposition. Hepatoprotective effects of op-HE were comparable to those of HE. Conclusions : Present study suggests that op-HE as well as HE exhibit hepatoprotective effect against oxidative stress-mediated liver injury via Nrf2 activation.

Transforming Growth Factor-β: Biology and Clinical Relevance

  • YiKim, Isaac;Kim, Moses M.;Kim, Seong-Jin
    • BMB Reports
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    • v.38 no.1
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    • pp.1-8
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    • 2005
  • Transforming growth factor-$\beta$ is a pleiotropic growth factor that has enthralled many investigators for approximately two decades. In addition to many reports that have clarified the basic mechanism of transforming growth factor-$\beta$ signal transduction, numerous laboratories have published on the clinical implication/application of transforming growth factor-$\beta$. To name a few, dysregulation of transforming growth factor-$\beta$ signaling plays a role in carcinogenesis, autoimmunity, angiogenesis, and wound healing. In this report, we will review these clinical implications of transforming growth factor-$\beta$.

Establishing the Supplementary Quantitative Guidelines for Successful Establishment of NRF Grant Funding Mechanism on Basic Research (한국형 그랜트 지원방식 도입에 따른 선정평가 효율화를 위한 정량적 가이드라인 수립에 관한 연구)

  • Seo, Ok-Ee;Park, Kwisun;Shin, Suk Kyung;Lee, Sung Jong;Rhie, Won Geun;Lee, Yun Hee
    • Journal of Korea Technology Innovation Society
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    • v.16 no.2
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    • pp.424-443
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    • 2013
  • National Research Foundation of Korea (NRF) provides underpinning to boost international and domestic competitiveness in basic science and engineering (S&E) research. In 2012, NRF came up with the idea about implementing koreanized grant funding system and a NRF grant funding mechanism on basic research was applied to General Researcher program. The main components of the mechanism are 1) no final evaluation, instead intensive evaluation for next proposal submission, 2) no paper account report, instead reporting it online, 3) no lengthy final report, instead unloading a brief overview of research achievements. For successful establishment of the NRF grant funding mechanism, the quality and quantity-based quantitative guidelines of research achievement for various research areas are essential. In this study, we suggest 3 quantitative indexes and these quantitative guidelines provides a supplementary tool for researcher's capability review. These guidelines will be also useful to elevate the reliability and objectivity of peer review.

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No Collapse Design for Typical Bridges (일반교량의 붕괴방지설계)

  • Kook, Seung-Kyu
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.3
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    • pp.163-172
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    • 2014
  • The purpose of earthquake resistant design for typical bridges is the No Collapse Design and the Earthquake Resistant Design Part of Roadway Bridge Design Code provides a design process to construct the Ductile Failure Mechanism for the bridge structure. However, if it is not practical to provide the Ductile Failure Mechanism due to structure types or site conditions, the Brittle Failure Mechanism is an alternative way to get the No Collapse Design. As well as the existing design process constructing the Ductile Failure Mechanism, the Earthquake Resistant Design Part provides a ductility-based design process as an appendix, which is prepared for bridges with reinforced concrete piers. According to the new design process, designer determines a required response modification factor for substructure and transverse reinforcement for confinement therefrom. In this study, a typical bridge with steel bearing connections and reinforced concrete piers is selected for which the existing as well as the ductility-based design processes are applied and different results from the two design processes are identified. Based on the results, an earthquake resistant design procedure is proposed in which designers should consider the two design processes.

An Integrated Design Process for Manufacturing and Multidisciplinary Design Under System Uncertainty

  • Byeng Dong
    • International Journal of Precision Engineering and Manufacturing
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    • v.5 no.4
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    • pp.61-68
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    • 2004
  • Necessity to address engineering system uncertainties in design processes has long been acknowledged. To obtain quality of product, a safety factor is traditionally used by many design engineers due to its easy of use and comprehension. However, the safety factor approach often yields either conservative or unreliable designs, since it ignores the type of probability distribution and the mechanism of uncertainty propagation from the input to the output. For a consistent reliability-based design, two fundamental issues must be investigated thoroughly. First, the design-decision process that clearly identifies a mechanism of uncertainty propagation under system uncertainties needs to be developed, which must be an efficient and accurate process. To identify the mechanism more effectively, an adaptive probability analysis is proposed by adaptively setting probability levels through a posteriori error estimation. The second is to develop the design process that not only yields a high quality design but also a cost-effective optimum design from manufacturing point of view. As a result, a response surface methodology is specially developed for RBDO, thus enhancing numerical challenges of efficiency and complicatedness. Side crashworthiness application is used to demonstrate the integrated design process for product and manufacturing process design.

An Empirical Study on Key Success Factors of Company Informatization and Informatization Performance Determinants - Focused on SER-M Framework - (기업 정보화 핵심 성공요인과 정보화 성과 결정요인에 관한 실증 연구 - SER-M Framework을 중심으로 -)

  • Choi, Hae-Lyong;Gu, Ja-Won
    • Management & Information Systems Review
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    • v.36 no.2
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    • pp.277-306
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    • 2017
  • Most past studies on the Critical Success Factors of Company Informatization focused on the completeness of Informatization and its financial effect, and there have not been enough studies on whether a company's management strategies can be supported by establishing Informatization direction. This implies that there must be verification on the followings; whether Informatization focuses on steering the implementation of management strategies, what correlation there are between major mechanism factors and Informatization performance. This also implies that there must be a new study to re-interpret the existing success factors of Informatization into strategic management paradigm. The purpose of this study is to empirically verify the influence of subject, environment, resource, and mechanism factors on informatization achievement, and to analyze the differences in influence of informatization success factors on informatization achievement depending on domestic large corporations and SMEs. This study presented the verification results for seven research hypotheses. It was confirmed through empirical analysis that securing resource factor was significant in informatization performance and that all sub-factors of learning mechanism and coordination mechanism were also significant in enterprise informatization achievement. In addition, it was confirmed through the control effect analysis depending on enterprise size that the differences in informatization performance of large corporations and SMEs are due to support environment factor, learning mechanism, and selection mechanism. The implications of this study are as follows: First, the significance of mechanism factors such as learning, internal coordination, and external coordination are relatively higher than other factors in informatization achievement. Secondly, informatization success factors that SMEs must focus on achieving are presented by analyzing the differences on informatization achievement of large corporations and SMEs. Third, since empirical research for informatization success mechanism factors not covered empirically in the prior research was directly progressed, it is thought that it could provide a comprehensive understanding for mechanism factors. In addition, this study is thought to provide a practical contribution that can be applied to other industrial areas and enterprises.

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