Determinants of Effecting Customer Loyalty : Comparison among Korean, Japanese and Chinese Online Game Market

이상철,상균영,구자철,서영호,Lee, Sang-Chul,Xiang, Jun-Yong,Gu, Ja-Chul,Suh, Yung-Ho The Korean Operations Research and Management Scie 2006 經營 科學 Vol.23 No.2

The purposes of this research are to identify causalities among flow and customer loyalty In Chinese online games, and to identify the factors by which flow are influenced. This research tests the model with Chinese on-line game users and compare this result with Korea and Japanese results which were conducted by Lee's research. These implications are thought to be helpful for Korean online game companies to understand the Chinese online game user and to develop the penetration strategies. The results indicated that significant Path coefficients to flow were the convenience of operator, the provision of information, the reality of design. The results indicated that significant path coefficients to customer loyalty were the involvement of virtual community and flow. The involvement of virtual community to flow was not significant but to customer loyalty was significant. The provision of information was negatively influenced on flow. The result of comparison indicated that the path coefficients were different among nations. Korea online game companies need to develop the indigenized online game and to Provide the information to their Chinese partner correctly and quickly.

전산화단층사진을 이용한 타액선의 정량분석에 관한 연구

이상철,이삼선,허민석,최순철,박태원,유동수,Lee Sang-Chul,Lee Sam-Sun,Heo Min-Suk,Choi Soon-Chul,Park Tae-Won,You Dong-Soo 대한영상치의학회 1999 Imaging Science in Dentistry Vol.29 No.1

Purpose: The purpose of this study was to calculate the size and CT number of both normal parotid and submandibular gland. and evaluate their relation to sex, age and obesity using computed tomography. Materials and Methods: The computed tomography was performed parallel to the Frankfurt plane in 46 subjects with healthy salivary gland. The subjects were divided into the three groups (young, middle. old) according to their ages. The size of salivary gland was determined as maximum cross-sectional area and the CT number of salivary gland was determined as the mean CT number of three ROI's. The body mass index was calculated from weight and height. Results: The mean maximum cross-sectional area was 7.79(±1.25)cm² on parotid gland and 4.12(±0.83) cm² on submandibular gland. The mean CT number was -4.43(±23.87) HU on parotid gland and 50.01(±15.63) HU on submandibular gland. There was decreasing pattern of the maximum cross-sectional area of submandibular gland and the CT number of both parotid and submandibular gland according to age(p<0.05). As the body mass index increased. the maximum cross-sectional area of parotid gland increased and CT number of both parotid and submandibular gland decreased(p<0.05). The maximum cross-sectional area of submandibular gland in male was larger than that in female(p<0.05). As the maximum cross-sectional area and CT number of left salivary gland increased. those of right gland increased(p<0.05). Conclusion : Intra-individual differences in salivary gland size and CT number is considered in the age and individual obesity.

광대싸리잎의 페놀성 화합물에 대한 화학적 연구

이상철,안병태,박웅양,이승호,노재섭,이경순,Lee, Sang-Chul,Ahn, Byung-Tae,Park, Woong-Yang,Lee, Seung-Ho,Ro, Jai-Seup,Lee, Kyong-Soon 한국생약학회 1994 생약학회지 Vol.25 No.2

A chemical examination of the aqueous acetone extract of the leaves of Securinega suffruticosa has led to the isolation of nine phenolic compounds. On the basis of chemical and spectroscopic evidences, the structures of these compounds were established to be gallic acid(1), corilagin(2), helioscopinin B(3), geraniin(4), bergenin (5), norbergenin(6), 11-O-galloyl norbergenin(7), gallocatechin(8) and rutin(9).

Rhizobium trifolii Malonyl - CoA Synthetase 의 촉매반응에 관여하는 아미노산 Residue 의 화학변형

이상철,김유삼 ( Sang Chul Lee,Yu Sam Kim ) 생화학분자생물학회 1993 BMB Reports Vol.26 No.3

Malonyl-CoA synthetase from Rhizobium trifolii was inactivated by 2,3-butanedione and diethylpyrocarbonate (DEP). In each case, inactivation followed pseudo first-order kinetics. The second-order rate constant for the inactivation by 2,3-butanedione was 17.4M^(-1)·min^(-1) at pH 8.0, 30℃. DEP rapidly inactivated the enzyme with the second-order rate constant, 780 M^(-1)·min^(-1) at pH 7.1, 30℃. The reaction order of inactivation with respect to reagents were 1.06 and 1.03 respectively. The substrate, ATP, afforded the protection against the inactivation of the enzyme caused by the reagent, respectively. These results indicate that arginine and histidyl residues essential for the enzyme activity are located at or near the ATP binding region of the active site.

Pyridoxal - 5 ' - Phosphate 에 의한 Rhizobium trifolii Malonyl - CoA Synthetase 의 화학변형

이상철,김유삼 ( Sang Chul Lee,Yu Sam Kim ) 생화학분자생물학회 1993 BMB Reports Vol.26 No.3

Pyridoxal-5`-phosphate inactivated malonyl-CoA synthetase from Rhizobium trifolii reversibly. The second-order rate constant, K_i was 2975 M^(-1) · min^(-1) at pH 7.0, 30℃. Inactivation of malonyl-CoA synthetase by PLP was reversed by dilution but not after reduction with NaBH₄. The spectra of malonyl-CoA synthetase, inactvated by PLP and reduced by NaBH₄, showed a characteristic Schiff base absorption change at 325 nm. ATP protected the enzyme from inactivation by PLP. These studies indicated that an essential amine is located at or near ATP binding region of the enzyme active site.

고속 열차용 대형 알루미늄 부품의 GAP 대응 로봇 자동화 용접 기술

이상철,Lee, Sang Chul 대한용접접합학회 2013 대한용접·접합학회지 Vol.31 No.1

Robotized MIG welding of large aluminium components for high speed trains is state-of-the-art. The implementation of online laser cameras enables seam tracking and adoptive modification of welding parameters. A constant fill is achieved regardless of the gap tolerances. Friction Stir Welding has been introduced to the market as a reliable and fast joining technology. The advantages of high welding speeds and the elimination of arc light, fumes and liquefaction in the welding spot lead to economical realisation of heavy-duty gantry systems. FSW robots offer a high flexibility with regard to welding of curved parts, and can be equipped with laser cameras for exact joint tracking.

분석자동화를 위한 용액 조제 시스템 설계에 관한 연구

이상철,강성준,정양희,Lee, Sang-Chul,Kang, Seong-Jun,Joung, Yang-Hee 한국전자통신학회 2013 한국전자통신학회 논문지 Vol.8 No.7

석유화학 단지에서는 보다 완성도 높은 제품을 위한 많은 연구 개발이 진행되고 있으며 이 과정에서 제품의 중간 및 완성 제품에 대한 분석은 필수적이다. 그러나 이와 같은 분석 작업들이 아직도 많은 부분에서 수작업에 의한 분석 시료가 제조되고 있고 위험한 화학물질에 노출되어 열악한 환경에서 분석이 이루어지고 있다. 본 연구에서는 이와 같은 문제점을 해결하기 위하여 분석 자동화를 위한 멀티 제어 시스템을 개발하였다. 또한 이들 장치의 유기적인 동작과 자동화를 위한 프로그램을 개발하여 적용하고 이들 장치의 신뢰성 검증을 위한 실험을 통하여 표준 용액 조제를 위한 정량 펌프의 정확도가 ${\pm}0.01m{\ell}$의 오차 범위를 갖는 매우 우수한 결과를 얻을 수 있었다. Petrochemical complex has been a lot of research for the development of a more mature product and analysis for mid-process and finished products is essential in these process. But these analyzes are still by hand work samples being manufactured in many parts. Moreover they are exposed to hazardous chemical and such as the analysis is being made in a very poor working conditions. In this paper, in order to solve such problems the multi control system has been developed for the automated analysis. In addition, the organic behavior of these systems and the development of a program for the automated applied, and throughout the experiment to verify the reliability of this device for the accuracy of the dosing pumps for the standard solution prepared with a range of error of ${\pm}0.01m{\ell}$ was able to get a very good experimental results.

Pyridoxal-5'-Phosphate에 의한 Rhizobium trifolii Malonyl-CoA Synthetase의 화학변형

이상철,김유삼,Lee, Sang-Chul,Kim, Yu-Sam 생화학분자생물학회 1993 한국생화학회지 Vol.26 No.3

Pyridoxal-5’-phosphate가 Rhizobium tifolii에서 정제한 malonyl-CoA synthetase를 가역적으로 불활성화 하였다. 반응의 2차 속도상수는 pH 7.0, $30^{\circ}C$에서 $2975 M^{-1}{\cdot}min^{-1}$이었다. PLP에 의해 불활성화된 효소는 완충용액으로 희석하였을 때 가역적으로 활성을 회복하였으나, $NaBH_4$로 환원 후 희석한 효소는 활성을 회복하지 못하였다. PLP와 반웅 후 $NaBH_4$로 환원한 효소액은 325 nm에서 톡징적인 Schiff base의 홉광도 변화를 보였다. ATP가 PLP에 의한 효소의 불활성화를 저해하였다. 이러한 결과들은 malonyl-CoA synthetase의 ATP 결합부위나 그 주위에 효소활성에 필수적인 amine group이 존재함을 시사한다. Pyridoxal-5'-phosphate inactivated malonyl-CoA synthetase from Rhizobium trifolii reversibly. The second-order rate constant, $K_i$ was $2975 M^{-1}{\cdot}min^{-1} $ at pH 7.0, $30^{\circ}C$. Inactivation of malonyl-CoA synthetase by PLP was reversed by dilution but not after reduction with $NaBH_4$. The spectra of malonyl-CoA synthetase, inactvated by PLP and reduced by $NaBH_4$, showed a characteristic Schiff base absorption change at 325 nm. ATP protected the enzyme from inactivation by PLP. These studies indicated that an essential amine is located at or near ATP binding region of the enzyme active site.

인체 α 1 - antitrypsin cDNA 의 분리 및 E . Coli 내에서의 발현

이상철,유명희 ( Sang Chul Lee,Myeong Hee Yu ) 생화학분자생물학회 1989 BMB Reports Vol.22 No.2

Human α1-AT cDNA was screened from human liver cDNA library, by use of oligonucleotide probes. DNA insert of 1.3 kbp from a positive clone was subcloned into pUC9 plasmid and was analyzed by restriction enzyme digestion and partial DNA sequencing. The obtained gene was identical to human αl-AT cDNA reported previously. In order to express αl-AT cDNA under regulation of tac promoter, expression vector pT-AT was constructed. E. coli JM109 cells transformed with pT-AT showed αl-AT activity upon induction of recombinant protein synthesis. The recombinant αl-AT was immunologically identical to authentic αl-AT that was purified from human blood. When the recombinant cell lysates were analyzed on SDS-polyacrylamide gel electrophoresis, the expressed α1-AT was not detected by staining with Coomassie Brilliant Blue. However Western blotting of the same gel, using rabbit IgG against αl-AT and peroxidase-conjugated goat anti-rabbit IgG antibody, showed the existence of αl-AT at the expected molecular weight region. Molecular weight of recombinant αl-AT was slightly lower than that of authentic αl-AT; which presumably was due to lack of glycosylation inside E. coli cells.

오리의 Urpygial Gland 에 있는 Glucose - 6 - phosphate Dehydrogenase 의 활성에 관여하는 Essential Cysteine 과 Arginine residues

이상철,김유삼 ( Sang Chul Lee,Yu Sam Kim ) 생화학분자생물학회 1985 BMB Reports Vol.18 No.2

Glucose-6-phosphate dehydrogenase from the uropygial gland of duck was purified in an electrophoretically homogenous form and its essential amino acid for catalysis was investigated. Three -SH group directed reagents, p-chloromercuriphenylsulfonic acid, 5,5`-dithio-bis-(2-nitrobenzoic acid) and N-ethylmaleimide, inhibited the enzyme activity, and arginine directed reagent, phenylglyoxal, also inhibited the enzyme activity. The inhibition of the enzyme by these reagents was protected by addition of NADP+ whereas it was not affected by that of glucose-6-phosephate indicating that essential -SH and guanidino group are located on the NADP^+ binding region of active site. Mg^(++) promoted the inhibition of the enzyme by the -SH and guanidine .group directed reagents. But the promotion of the inhibition was considerably recovered in the presence of EDTA. This results suggested that divalent metal cation may affect the conformational change toward the susceptible one against modifying reagents.