• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.656-662
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• 2001

Angiogenesis is known as a crucial process in the growth and spreading of tumor cells. Accordingly, the effective inhibition of this process would appear to be a promising way to cure angiogenesis-related diseases, including cancer. This study demonstrates that acalycixenolide E (AX-E) from the marine organism Acalycigorgia inermis exhibits a potent anti-angiogenic activity both in vitro and in vivo. AX-E inhibits the bFGF-induced proliferation of HUVECs in a dose dependent manner, along with the bFGF-induced migration, invasion, and tube formation of HUVECs. Moreover, AX-E potently inhibits the in vivo neovascularization of the chorioallantoic membranes (CAMs) of growing chick embryos. interestingly, AX-E suppresses the expression of metalloproteases 2 and 9, yet shows no effect on their activities. The novel chemical structure and potent anti-angiogenic activity of AX-E will be of great value in elucidating the molecular mechanism of angiogenesis as well as in the development of a novel anti-angiogenic drug.

• BMB Reports
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• v.42 no.9
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• pp.541-551
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• 2009

Amyloidogenesis defines a condition in which a soluble and innocuous protein turns to insoluble protein aggregates known as amyloid fibrils. This protein suprastructure derived via chemically specific molecular self-assembly process has been commonly observed in various neurodegenerative disorders such as Alzheimer's, Parkinson's, and Prion diseases. Although the major culprit for the cellular degeneration in the diseases remains unsettled, amyloidogenesis is considered to be etiologically involved. Recent recognition of fibrillar polymorphism observed mostly from in vitro amyloidogeneses may indicate that multiple mechanisms for the amyloid fibril formation would be operated. Nucleation-dependent fibrillation is the prevalent model for assessing the self-assembly process. Following thermodynamically unfavorable seed formation, monomeric polypeptides bind to the seeds by exerting structural adjustments to the template, which leads to accelerated amyloid fibril formation. In this review, we propose another in vitro model of amyloidogenesis named double-concerted fibrillation. Here, two consecutive assembly processes of monomers and subsequent oligomeric species are responsible for the amyloid fibril formation of $\alpha$-synuclein, a pathological component of Parkinson's disease, following structural rearrangement within the oligomers which then act as a growing unit for the fibrillation.

• The KSFM Journal of Fluid Machinery
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• v.15 no.4
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• pp.50-54
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• 2012

Wind-power generation, which is recently drawing attention as one of renewable energies across the world, has been developed mainly by Europe. As the demand for the wind-power generation rose and the amount of wind-power generation increased, the studies on megawatt-class wind-power system have been active, and the use of composite with such properties as less weight, more strength, anti-corrosion and environment-friendliness has required gradually. In other word, wind turbine tower will be required to be lighter, more reliable and more consistent. Therefore it is necessary to lose weight of the wind turbine tower. This points squarely toward hybrid/composite tower production growing. It is important to note however that hybrid/composite tower production as it is today is flawed and that there are ways to improve greatly on the performance of these towers in manufacturing process and in their in-service performance. Through this, we have some detail on the current process and its advantage of cost and weight of towers.

• Architectural research
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• v.18 no.1
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• pp.21-29
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• 2016

Importance of FM has rapidly increased because of its growing business. However, due to lack of clarity and identity of FM in professional areas, standardization of FM became to be imperative in such a rapidly changing global business environment. Facility services are defined as the provision of support the primary activities of an organization, delivered by an internal or external provider. Majority of FM activities are services related to 'space and infrastructure' and 'people and organization' (CEN, 2011). The purpose of this study is to investigate definitions and characteristics of FM from both globally and domestic environment, by comparison with international or national standards, to identify quality management in FM and service characteristics of FM, to investigate the differences in service level elaboration in FM, and to suggest standard issues of quality management in FM service quality. This study examines contents of the European Standards in FM, Part 3 'Guidance on quality in Facility Management, especially for the process of QM standardized by CEN (2011) and explores undefined issues such as service level, measurement metrics according to service characteristics of FM. The European FM Standard guides the common process of QM in terms of requirements specification, service level elaboration, measurement metrics development although it does not specifically address various service levels, specific performance metrics and indicators.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.57-63
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• 2014

At present, a high-speed swivel tool head of a small size is required to improve the productivity of CNC automatic lathes. Hence, there is growing interest in shorter machining times with higher cutting speeds. However, an increase in the rotation speed of a swivel tool head also has adverse effects, such as vibration and noise caused by the swivel tool head system. In this work, the fatigue life and contact pressure of a swivel tool head bearing system driven by gears were calculated. Based on the calculated results, a prototype swivel tool head was manufactured and its static and dynamic characteristics, i.e., the vibration, noise and precision, were measured using a reliability testing device which allows the application of cutting force to the end of the swivel tool head.

• Journal of Korean Academy of Nursing
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• v.44 no.1
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• pp.1-12
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• 2014

Purpose: This study was done to explore and understand acculturation focusing on reproductive health of immigrant women. Methods: For the research sixteen immigrant women were selected by snowball sampling. Qualitative data were accumulated by in-depth interviews and private document collection. Raw data was analyzed following Mandelbaum's conceptual framework. Results: The dimensions of immigrant women consisted of existence: emerging from the new environment in which it was hard to communicate and to get acquainted with others, reproduction: in the absence of learning and experience, reproductive health crisis, parenting: unmanageable burden. Turnings of life involved 'Inconvenience in one's eyes, vent for conflict and tension: pregnancy', 'strange medical care: accoucheur, rapid medical service', 'pain of morning sickness: poor maternal nutrition', 'manifestation of protective instinct for life'. In adaptations, content was as follows. 1) Standing alone as a Korean housewife, 2) Becoming aware of Korean maternal instinct: thirst for education supporting, 3) Rediscovery of family: growing maternal sense of existence. Conclusion: The results of this study show the acculturation process and the meaning of events related to reproductive health in current lives and can contribute to an integrated understanding of married immigrant women in Korean culture.

• Journal of Powder Materials
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• v.22 no.1
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• pp.10-14
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• 2015

In recent years, industrial demands for superior mechanical properties of powder metallurgy steel components with low cost are rapidly growing. Sinter hardening that combines sintering and heat treatment in continuous one step is cost-effective. The cooling rate during the sinter hardening process dominates material microstructures, which finally determine the mechanical properties of the parts. This research establishes a numerical model of the relation between various cooling rates and microstructures in a sinter hardenable material. The evolution of a martensitic phase in the treated microstructure during end quench tests using various cooling media of water, oil, and air is predicted from the cooling rate, which is influenced by cooling conditions, using the finite element method simulations. The effects of the cooling condition on the microstructure of the sinter hardening material are found. The obtained limiting size of the sinter hardening part is helpful to design complicate shaped components.

• Journal of Information Technology Applications and Management
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• v.27 no.1
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• pp.59-73
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• 2020

There is a growing interest in convergence. National R & D is also providing various policies and institutional support to promote convergence research. Convergence research, however, does not clearly specify its characteristics at the academic and government levels. This research proceeds with the process of collecting, refining, analyzing, modeling, verifying and visualizing national R & D data through the National Science and Technology Information Service (NTIS). The method is to derive the convergence research characteristics and to derive through text mining, focusing on the unstructured information of national R & D project data. The study confirmed that there was a difference in perception between the definition of converged research and the research site. In order to improve this, the research suggested that convergence among research subjects, collaboration among research topics reflecting various backgrounds and characteristics of researchers, and analysis of characteristics of convergence research using information were suggested in the process of establishing convergence policy.

• The Magazine of the IEIE
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• v.35 no.7
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• pp.57-71
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• 2008

The last decade has witnessed great improvements in power semiconductor devices thanks to the advanced design and process, which have made it possible to significantly improve the electrical performances of electronic systems while simultaneously reducing their site, weight and perhaps most importantly reducing their cost. Among the power semiconductor devices, IGBT will be a key semiconductor component for power industry since it has a huge potential to cover large areas of power electronics from small home appliances to heavy industries. Currently, only a few limited power semiconductor manufacturers supply most of the industrial consumptions of power IGBT and its modules. Therefore, a large portion of technology in the power industry is dependent on other advanced countries. In this regard, to independently build power IGBT devices and the relevant power module technology, Korean government initiated a new 5-year project 'Power IT,' which also aimed at booming the business of the power semiconductor and the allied industries. With the success of this power IT project, it is expected that the power semiconductor technology will be a basis to foster the high power semiconductor industry and moreover, there will be more innovative developments in the Korea region and globally Also, forming the channel between the customers and suppliers, it is possible to effectively develop the customized power products, which could strengthen the competitiveness of Korean power industry. Furthermore, the power industry including semiconductor manufacturers will be technologically self-supporting and be able to obtain good business opportunities, and eventually increase the share in the growing power semiconductor market, which could be positioned as a major industry in Korea.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.18-26
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• 1997

Grinding burn formed on the ground surface is related to the maximum temperature of workpiece surface and wheel tempertaure in the grinding process. The thermal characteristics of workpiece and grinding conditions on the surface tempertaure of the oxidation growing layer after get out of contact with the grinding wheel. The assumption used in grinding power signatures leads to the local temperature distribution between grinding wheel and workpiece, i.e., a single curve determines temperatures anywhere within the grinding wheel at anytime. This information is useful in the study of the grinding burn penetration into the wheel and thus provides an presentation of grinding trouble monitoring for the burning. On the basis of grinding power signatures in the wheel, thermally optimum grinding conditions are defined and controlled. To cope with grinding burn, the use of grinding power signatures is an effective monitoring systems when occurring the grinding process. In this paper, the identified parameters suggested in this study which are derived from the grinding power signatures are presented, and prediction model by grinding power utilized a linear regression algorithm is applied.