• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.153-161
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• 2005

파이브로넥틴은 세포외기질에 존재하는 당단백질로 세포의 부착, 이동, 성장 및 분화에 관여하며, 섬유아세포 성장인자는 세포의 증식 이동 및 분화에 영향을 주는 중요한 성장인자로 알려져 있다. 최근 연구에 의하면, 파이브로넥틴은 조골세포의 타이태늄 임플란트 표면으로 이주와 증식 및 골생성을 촉진하며, 섬유아세포 성장 인자는 파이브로넥틴에 상승작용을 한다고 보고된 바 있다. 이 실험의 목적은 파이브로넥틴 및 섬유아세포 성장인자의 복합 단백질을 이용하여 타이태늄 임플란트의 골 반응을 알아보는 것이다. 체중 2.5 kg 내외의 건강한 18 마리의 웅성가토를 준비하여 무균 사육하였고, 순수 타이태늄을 절삭가공하여 직경 3.5mm, 길이 6mm 의 machined surface를 지니는 screw type 의 임플란트를 준비하였다. 사람의 유전자를 기초로, 유전자 재조합법을 통해, 적절한 primer를 이용하여 얻은 섬유아세포 성장인자를 파이브로넥틴 III 형 분절의 9-10 번 도메인에 결합시켜 얻은 복합 단백질을 준비된 임플란트에 표면처리하여 실험군으로 하였고, 표면처리하지 않은 임플란트를 대조군으로 하여, 가토의 좌우 경골에 각각 2 개씩의 임플란트를 식립하였다. 4주 후, 가토를 희생시켜 각 경골 당 한 개의 임플란트에서 뒤틀림 제거력을 측정하였고 나머지 임플란트 식립 부위 에서는 경골을 포함하는 조직표본을 제작하였다. 조직표본상에서 골접촉이 가장 좋은 3 개의 나사산의 길이를 측정하고, 나사와 접촉하는 골의 길이를 측정하여 골-임플란트 접촉도를 구하고, 같은 부위에서 나사산 사이의 면적과 골이 차지하는 면적을 비교하여 골생성률을 얻었다. 실험군과 대조군의 결과는 Student t-test 를 이용하여 신뢰도 95% 수준에서 통계학적 유의성을 검정하였다. 파이브로넥틴과 섬유아세포 성장인자의 복합 단백질로 표면처리된 임플란트와 표면처리를 하지 않은 임플란트는 뒤틀림 제거력에서는 통계적 유의성이 나타나지 않았으나, 골-임플란트 접촉도와 골생성률에서 복합 단백질로 처리된 임플란트가 통계적으로 유의하게 높은 결과를 보였다. 이상의 연구결과로, 섬유아세포 성장인자와 파이브로넥틴 복합 단백질로 처리한 타이태늄 임플란트가 주변 골 형성을 촉진시켜, 골유합을 증진시킴을 알 수 있었다. 따라서, 복합 단백질이 타이태늄 임플란트의 성공률을 높이기 위한 표면개질 물질로 이용될 가능성을 확인할 수 있었다.

• Journal of Technology Innovation
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• v.24 no.3
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• pp.107-137
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• 2016

By analyzing a nationwide survey on Korean publics, this study examines the social determinants of public support for three types of scientific research-basic research aimed at pure knowledge, applied research toward industrial application, and research for social problem-solving which aims to enhance ordinary citizens' quality of life. The present study finds the differential effects of social- and political value orientations on the level of public support for respective types of research. As ones have more progressive in their subjective political orientations, they are more likely to support research for social problem-solving than other types of research, while conservatives tend to support basic research and those with neo-liberal ideology tend to support applied research. The Korean public also tends to perceive research for social problem-solving as a counter to basic research while it has been developed against the conventional emphasis on applied research in Korea. Also, the level of support for research for social problem-solving increases with the higher level of trust in scientific authority and expertise, while it has been developed against expertism and included public engagement in science as an important element. Finally, those who have lower income tend to support for research for social problem-solving than other types of research. The implications of these findings are discussed.

• Management & Information Systems Review
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• v.35 no.4
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• pp.141-153
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• 2016

This study estimates the productivity change of pharmaceutical industry and decompose the change into technical efficiency change and technological change to explore ways to improve the productive efficiency. Unlike most previous studies, this study employs the non-radial and non-oriented slacks-based Malmquist productivity index which can deals directly with the input excesses and output shortfalls. In addition a smoothed bootstrap method is applied to estimate statistical confidence intervals for the Malmquist Index and its components. For the empirical analysis a balanced panel data set is constructed covering ten years over the period from 2005 to 2014. The input variables used in this study are number of workers, tangible assets and major production cost. The gross production is selected as a main output variable. The empirical results suggest that the productivity of pharmaceutical industry has decreased due mainly to decline in the technological progress rather than improvements in technical efficiency. An analysis result shows that the scale efficiency outweighs the pure efficiency in determining the technical efficiency of pharmaceutical industry. Therefore, in order to enhance the competitiveness of domestic pharmaceutical industry, it is important to continue supporting policies to promote the technology innovation capability through efficient R&D investment and industry reform strategy.

• Journal of KIISE:Information Networking
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• v.30 no.1
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• pp.75-81
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• 2003

User authentication, including confidentiality, integrity over untrusted networks, is an important part of security for systems that allow remote access. Using human-memorable Password for remote user authentication is not easy due to the low entropy of the password, which constrained by the memory of the user. This paper presents a new password authentication and key agreement protocol suitable for authenticating users and exchanging keys over an insecure channel. The new protocol resists the dictionary attack and offers perfect forward secrecy, which means that revealing the password to an attacher does not help him obtain the session keys of past sessions against future compromises. Additionally user passwords are stored in a form that is not plaintext-equivalent to the password itself, so an attacker who captures the password database cannot use it directly to compromise security and gain immediate access to the server. It does not have to resort to a PKI or trusted third party such as a key server or arbitrator So no keys and certificates stored on the users computer. Further desirable properties are to minimize setup time by keeping the number of flows and the computation time. This is very useful in application which secure password authentication is required such as home banking through web, SSL, SET, IPSEC, telnet, ftp, and user mobile situation.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.183-188
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• 2005

Effects of co-solvent polarity, citric acid, pressure, temperature, run time, and co-solvent ratio on extraction of major flavonoids from Lonicera Flos were investigated using supercritical fluid $CO_{2}(SF-CO_{2})$. HPLC analysis revealed addition of pure methanol resulted in low extraction yield of major flavonoids, luteoloin (Lu), Quercetin (Qu), Apigenin (Ap). Under same condition, as co-solvent polarity increased, yields of major flavonoids increased gradually, At optimum co-solvent extraction condirion of 60% aqueous methanol (10%, v/v), yields of Lu, Qu, and Ap were 42.09, 28.18, and 3.49 mg/100 g, respectively. Addition of citric acid to 60% aqueous methanol gave higher, with addition of 1% citrie acid resulting in highest yields of 63.2 (Lu), 39.35 (Qu), and 5.79 (Ap) mg/100 g. Optimum extraction conditions of major flavonoids were 200 bar, $50^{\circ}C$, 60 min, and $CO_{2}$-methanol-water(20: 1.8: 1.2).

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.135-154
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• 2020

This paper analyzes the 5,521 samples of the small and medium-sized businesses(SMBs) obtained from the Korea Credit Guarantee Fund. From January 2014 to September 2019, 85% of the SMBs have 5 or fewer full-time employees. The proportion of SMBs is overwhelmed by the elderly men, and most founders are the CEO. Also, about 87% of the workplace types are rented, while 64% of the CEO's residence types are owner-occupation. 47% of the financial grade score is less than 10 points out of 100 and 80% of SMBs have less than 200 million won of the loan guarantee. In particular, the total guarantee loan amount or the days of net guarantee have significantly positive relations with the working period of the CEO in the same industry, the number of employees, the operation period of SMBs, and the corporate business type. In the case of the financial grading score which has the highest weight in overall credit rating gets higher with the higher number of employees, the longer the operation period, and the corporate business type. However, the quantified non-financial grading score has no significant relationship with other explanatory variables, except for the corporate business type. This implies that a non-financial grade score is measured by other determinants that are not observed by the Korea credit guarantee fund. The pure non-financial grade score has positive relations with the working period of the CEO. Overall, this paper would help Korean SMBs upgrade their credit ratings and expand the money supply when there is no standardized credit rating model or no publicly available evaluation criteria for SMBs. We expect this paper provides important insights for further research and policy-makers for SMBs. In particular, to address the financial needs of thin-filers such as SMBs, technology-based financial services (TechFin) would use alternative data to evaluate the financial capabilities of thin-filers and to develop new financial services.

• Journal of Popular Narrative
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• v.26 no.4
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• pp.9-41
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• 2020

Park Jong-won's debut film "Guro Arirang," based on a short story of the same title by Lee Moon-yeol, is the first commercial film to deal with labor struggles from a worker's point of view in the wake of the 1987 democratic movement, and a pioneering work in terms of representing female workers the Korean cinema has traditionally turned away from. In this film Park Jong-won tried to win the sympathy of the middle class for labor movement in spite of the red scare which still stood firm in the Korean society at that time. To convey its progressive message in a form acceptable to the middle class public, the film portrays labor issues in the light of universal humanity and ethics, not in terms of class hostility or struggle. Park Jong-won calls this point of view "common sense of normal people" and emphasizes its universality and objectivity. This study critically examines the cinematic strategies to deal with labor issues in a form acceptable to the public in a conventional and commercial film and the ideological implications of the "common sense of normal people" reflected in such strategies. The first chapter of the study reveals that the film destroys the irony of the original story and reduces the complex constellation of the characters to the conflict between pure good and evil, creating a melodramatic composition in which the good falls victim to evil. The tragedies suffered by the workers in the film are of course intended to arouse the audience's strong sympathy and solidarity with them. The second chapter shows that the film's various scenes and episodes converge on the them of compassion and grief, and are mostly based on cultural and real experiences and events that caused great public sensations at that time. Especially in the last decisive scene of the movie, the memory of the June 1987 uprising is strongly recalled. So "Guro Arirang" can be seen as a patchwork of proven cases of compassion and grief. The third chapter examines the implications of the scene where the workers turn back demands for wages and put the issues of human treatment and trust to the forefront at the crucial moment of their struggle. It appeals to universal moral values and sentiments that everyone has to acknowledge and removes the political dimension from the workers' campaign. While the film tends to become a pure story of humanity marginalizing irreconcilable conflicts of class interest, the workers fall to the position of passive victims who can be deeply sympathetic on the one hand, and on the other, are idealized as leaders with noble attitude keeping themselves aloof from the hard reality. As a result, the movie loses its realistic ground and weakens its narrative probability. The scenes reminiscent of the 1987 uprising which evoke the solidarity between working and middle class fail to integrate harmoniously into the whole story of the film and remain only as fragmentary parts of the patchwork of compassion and grief.

• Journal of the Korean Geographical Society
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• v.49 no.5
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• pp.761-778
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• 2014

There has been relatively little study to model price for commercial property because of its low transaction volume in the market. Despite of this thin market character, this paper tried to estimate prices for commercial lots as accurate as possible. We constructed a model whose components consist of mean structure(global trend), exponential covariance function and a pure error term, and applied it to actual sales price data of Seoul. We explicitly took account of spatial autocorrelation of land price by utilizing a kriging technique, a representative method of spatial interpolation, because the land price of commercial lots has feature of differential price forming pattern depending on submarkets they belong to. In addition, we chose to apply a bayesian kriging to overcome data scarcity by incorporating experts' knowledge into prior probability distribution. The chosen model's excellent performance was verified by the result from validation data. We confirmed that the excellence of the model is attributed to incorporating both autocorexperts' knowledge and spatial autocorrelation in the model construction. This paper is differentiated from previous studies in the sense that it applied the bayesian kriging technique to estimate price for commercial lots and explicitly combined experts' knowledge with data. It is expected that the result of this paper would provide a useful guide for the circumstances under which property price has to be estimated reliably based on sparse transaction data.

• The Journal of Engineering Geology
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• v.24 no.2
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• pp.261-271
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• 2014

An almost permanent anchor (friction type) is resistant to ground deformation due to the friction between the soil and grout at a fixed length from the anchor body. The purpose of this study is to calculate the force of bearing resistance for a bearing anchor in enlarged boreholes. We conducted analytical and numerical analyses, along with laboratory testing, to find the quantities of bearing resistance prior to grouting in EBA (Enlarged Bearing Anchor) construction. The force of bearing resistance from the analytical method was defined as a function of general borehole diameter, expanded borehole diameter, and soil unconfined compressive strength. We also employed the Flac 3D finite difference numerical modeling code to analyze the bearing resistance of the soil conditions. We then created a laboratory experimental model to measure bearing resistance and carried out a pull-out test. The results of these three analyses are presented here, and a regression analysis was performed between bearing resistance and uniaxial compression strength. The laboratory results yield the strongest bearing resistance, with reinforcement 28.5 times greater than the uniaxial compression strength; the analytical and numerical analyses yielded values of 13.3 and 9.9, respectively. This results means that bearing resistance of laboratory test appears to be affected by skin friction resistance. To improve the reliability of these results, a comparison field study is needed to verify which results (analytical, numerical, or laboratory) best represent field observations.

• Horticultural Science & Technology
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• v.16 no.1
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• pp.21-24
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• 1998

RAPD markers were analyzed in order to detect the genetic variation and diversity of the fifty-two melon lines. SDS extraction method produced more and purer DNA than CTAB method. RAPD reaction conditions were optimized as follows ; 10ng template DNA, 270nM primer, $200{\mu}M$ each of dATP, dCTP, dGTP and dTTP, $0.3{\mu}unit$ dynazyme and 10x buffer brought to $15{\mu}l$ final volume with distilled water. The adequate annealing temperature was $39^{\circ}C$ and forty cycles of amplification produced the best RAPD band patterns. Among a total of 123 bands from 12 random primers, 25 polymorphic bands(20%) were selected as reliable markers. The average number of polymorphic bands per primer was 2.1 among the 52 lines. Intragroup genetic relationship based on the marker difference was closer than intergroup genetic relationship. The 52 lines could be grouped into two major group (Korean landraces and melon lines) and then melon group subdivided into two subgroups (net melon lines and no-net melon). This result corresponded to morphological grouping. Eight RAPD markers separated the Korean landraces and melon groups and four RAPD markers separated net melon and no-net melon groups.