• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2002년도 제38회 학술심포지움
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• pp.13-19
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• 2002

To elucidate the regulatory mechanism for expression of sialyl-glycoconjugates and their biological functions, ninetheen sialyltransferase cDNAs including eleven by our group or co-works have been cloned and characterized so far. The cloned sialyltransferases are classified into four families according to the carbohydrate linkages they synthesize: ${\alpha}2,3-sialyltransferase$ (ST3Gal I-VI), ${\alpha}$ 2,6-sialyltransferase (ST6Gal I), GalNAc ${\alpha}$ 2,6-sialyltransferase (ST6GalNAc I-VI), and ${\alpha}2,8-sialyltransferase$ (ST8Sia I-VI). Each of the sialyltransferase genes is differentially expressed in a tissue-, cell type-, and stage-specific manner. These enzymes differ in their substrate specificity and various biochemical parameters. However, enzymatic analysis conducted in vitro with recombinant enzyme revealed that one linkage can be synthesized by multiple enzymes. We present here an overview of structure and function of sialyltransferases performed by our group and co-works. Genomic structures and transcriptional regulation of two kinds of human sialyltransferase gene are also presented.

• Journal of the Korean Wood Science and Technology
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• 제17권3호
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• pp.28-44
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• 1989

This experiment was carried out to contribute to the synthetic methods of ligin model compounds. The ligin model compounds of arylglycerol-${\beta}$-arylether structure were synthesized in high yield through three or four reaction steps. The starting compound was commercial 3, 4, 5-trimethoxyace tophenone and the final compounds were 1-(2-methoxyphenoxy)-2 - (3, 4, 5 - trimethoxyphenyl)-ethanol(IV), 1-(3, 4, 5-trimethoxyphenyl)-2-(2-methoxy-phenoxy)-propandiol-1,3 (VI), 1-(2, 6-dimethoxyphenoxy)-2-(3, 4, 5-trimethoxyphenyl)-ethanol (VIII), and 1-(3, 4, 5-trimethoxyphenyl)-2-(2, 6-dimethoxyphenoxy)-propandiol-1, 3 (X). The structures of synthetic compounds were identified by IR, $^1H$-NMR spectroscopy and Mass spectrometry.

• 자원ㆍ환경경제연구
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• 제12권1호
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• pp.91-120
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• 2003

This paper is intended to measure sectoral sustainabilities and inter-industry linkage effects of natural capital depletion of the Korean industries, and to analyze sources of their change over time using the familiar input-output model. The sustainability indicator that we are measuring in this paper is based on the so-called genuine saving concept proposed by the World Bank(1997). We accommodated the concept in the extended analytical framework of Proops et al.(1999) to analyze sectoral sustainabilities of the Korean industries. We decomposed sectoral sustainabilities so measured into their composing factors based on the decomposition method devised by Chung & Rhee (2001). According to our analysis, overall sustainability of the Korean industries has been declined since 1995. In heavy and chemical, transportation, and electricity sectors, their sustainabilities has been gotten worse. Among four major factors influencing the sustainability, change in GDP was the most important followed by changes in savings, industrial structures, and demand patterns.

• Applied Biological Chemistry
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• 제13권3호
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• pp.181-186
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• 1970

1) 세균액화효소(BLA), 세균당화효소 (BSA), isoamylase에 의한 전분의 가수분해 조건을 조사한 다음 이들 효소를 여러가지로 배합하여 물엿을 만들었다. 네가지 물엿 중에서 BLA와 BSA 또는 isoamylase를 같이 사용하여 만든 것은 밀감류 통조림용 시럽으로서 설탕시럽과 비슷한 결과를 나타 내었다. 2) BLA 및 BSA에 의한 전분분해액 중에서 두가지 소당류를 분리하고 그들의 구조를 결정한 바 ${\alpha}-1,6$결합을 하나씩 가지는 5당류 및 6당류임을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1347-1353
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• 2005

Sets of sialic acid-containing trisaccharides having different internal and terminal linkages have been synthesized to develop a sensitive method for analysis of the reducing terminal linkage positions. The trisaccharides, sialyl($\alpha$ 2-3)Gal($\beta$ 1-3)GalNAc and sialyl($\alpha$ 2-3)Gal($\beta$ 1-X)GlcNAc where X=3, 4 and 6, were synthesized and examined using electrospray ionization (ESI)-collision induced dissociation (CID) tandem mass spectrometry (MS/MS). The compounds chosen for this study are related to terminal groups likely to be found on polylactosamine-like glycoproteins and glycolipids which occur on the surface of mammalian cells. The purpose of this study is to develop tandem mass spectrometral methods to determine detailed carbohydrate structures on permethylated or partially methylated oligosaccharides for future applications on biologically active glycoconjugates and to exploit a faster method of synthesizing a series of structural isomeric oligosaccharides to be used for further mass spectrometry and instrumental analysis.

• Journal of Korean Neurosurgical Society
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• 제37권2호
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• pp.154-156
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• 2005

We present a case of chondroblastoma in the thoracic vertebra. A 40-year-old patient with upper back pain and lower extremity weakness was admitted to our clinic. On neurological examination, the patient exhibited lower extremity spastic paraparesis. Magnetic resonance imaging revealed a mass infiltrating the 7th thoracic vertebra and its adjacent structures with concomitant compression of the epidural space. After right upper lung tuberculoma was resected through the transthoracic approach, T7 total corpectomy was done with anterior stabilization using a MESH cage and T7 rib bone graft. Two weeks after the first operation, remained part of vertebra was removed and posterior stabilization was performed using a pedicle screw fixation and cross linkage bar with the assistance of the navigation system. The final pathologic diagnosis of the vertebral lesion was benign chondroblastoma.

• 한국자동차공학회논문집
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• 제11권2호
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• pp.140-147
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• 2003

Full scale durability test in the laboratory is an essential of any fatigue life evaluation of components or structures of the automotive vehicle. Component testing is particularly important in today's highly competitive industries where the design to reduce weight and production costs must be balanced with the necessity to avoid expensive service failure. Generally, hydraulic road simulator is used to carry out the fatigue test and the vibration test. In this paper, the link unit which is able to realize the 3 element forces such as vertical force, lateral force, and longitudinal force that are applied to the road simulator is designed. Also, the designed link is verified with kinematics and inverse-kinematics. From this results, the designed factor satisfied the maximum stroke so that it satisfied the requirements for 3-axial road simulator.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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• pp.169-176
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• 2003

In the present study, a shape design optimization scheme in shell structures is implemented based on the integrated framework of geometric modeling and analysis. The common representation of B-spline surface patch is used for geometric modeling. A geometrically-exact shell finite element is implemented. Control points or the surface are employed as design variables. In the computation of shape sensitivity, semi-analytical method is employed. Sequential linear programming is applied to the shape optimization of surfaces. The developed integrated framework should serve as a powerful tool to design and analysis of surfaces.

• Journal of Electrical Engineering and Technology
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• 제9권4호
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• pp.1277-1282
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• 2014

Concentrated flux interior permanent magnet (CFIPM) motors have the advantage that their utilization of flux linkage is more efficient than that of general IPM motors and CFIPM motors are suitable for washing machine motors, which demand low-speed, high-torque specifications. However, low efficiency occurs in the low-speed high-torque mode considering the high-speed operation for spin mode. This paper proposes a magnet overhang structure between the rotor core that reduces leakage flux and improves efficiency for a CFIPM in wash mode. Optimization of the 3D design of magnet overhang structures is performed to improve the efficiency with the same quantity of permanent magnets. The validity of the optimal design is experimentally verified through the fabrication of prototypes.

• Asia pacific journal of information systems
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• 제11권4호
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• pp.1-25
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• 2001

Manufacturing firms face a paradigm shift from industrial systems driven by efficiency to post-industrial systems where success depends on a quick-response to customer demands for a variety of high-quality products. In essence, time is becoming a critical dimension for competition. New information technologies allow many firms to pursue time-based competitive strategies. The purpose of this research is to investigate the relationship among the types of information technology, behaviors of suppliers, the structures of new product development processes, and the competitiveness of the firms. The data for this study were collected from 96 Korean manufacturing firms that have implemented certain types of information technologies. Research results from LISREL analysis confirm that the competitiveness comes from product innovation capabilities and innovative product development process. But the linkage between the information technologies and the firms' competitiveness proves to be indirect. Suppliers, organizational culture related to IT, and some other factors also have indirect impact on the competitiveness. A summarized report of other findings is provided as well.