• Rapid Communication in Photoscience
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• 제4권2호
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• pp.37-40
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• 2015

To examine the photosensitized biomolecules damaging activity, dimethoxyP(V)tetrakis(2-naphthyl)porphyrin (NP) and dimethoxyP(V)tetraphenylporphyrin (PP) were synthesized. The naphthyl moiety of NP hardly deactivated the photoexcited P(V)porphyrin ring in ethanol. In aqueous solution, the naphthyl moiety showed the quenching effect on the photoexcited porphyrin ring, possibly through electron transfer and self-quenching by a molecular association. Binding interaction between human serum albumin (HSA), a water soluble protein, and these porphyrins could be confirmed by the absorption spectral change. The apparent association constant of NP was larger than that of PP. It is explained by that more hydrophobic NP can easily bind into the hydrophobic pockets of HSA. The photoexcited PP effectively induced damage of the tryptophan residue of HSA, through electron transfer-mediated oxidation and singlet oxygen generation. NP also induced HSA damage during photo-irradiation and the contributions of the electron transfer and singlet oxygen mechanisms were speculated. The electron transfer-mediated mechanism to the photosensitized protein damage should be advantageous for photodynamic therapy in hypoxic condition. The quantum yield of the HSA photodamage by PP was significantly larger than that of NP. The quenching effect of the naphthyl moiety is considered to suppress the photosensitized protein damage. In conclusion, the naphthalene substitution to the P(V)porphyrins can enhance the binding interaction with hydrophobic biomacromolecules such as protein, however, this substitution may reduce the photodynamic effect of P(V)porphyrin ring in aqueous media.

• 산경연구논집
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• 제10권1호
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• pp.59-67
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• 2019

Purpose - The Millennial Generation, which grew in the wake of the spread of the Internet and rapid changes in the media environment, is rapidly moving from the traditional broadcasting environment to the Internet-broadcasting environment in terms of content acceptance. With the emergence of UGC (User-generated content), the change in the status of single-person content creators enables the growth of multi-channel networks (MCN), a new content-distribution platform and an agency concept for single creators. Youtube-based MCN produces multiple single star producers and casts and provides its own video series through Youtube. It is also emerging as a major M&A target for global media providers in terms of providing content to a wide range of consumers with the same interests and consumption characteristics. In addition, for the Millennials generation, which are part of their lives, MCN is becoming the most suitable media for TGIF (Twitter, Google, i-phone, Facebook). Accordingly, this study defines newly emerging MCNs and analyzes the factors for accepting MCN-produced content based on the push-pull-mooring (PPM) model. Research design, data, and methodology - An empirical analysis is performed through a questionnaire survey. For this purpose, 204 people who have experience of watching MCN were studied. Collected data is processed through analysis of a structural equation model using R to test the hypothesis. Results - For the MCN service to become an alternative to existing media, it is necessary to continuously promote cultural diversity and diversity of attempts that conventional media cannot provide. It is the attractiveness of the alternative that has the greatest influence on the intention to switch to a MCN service. When we look at MCN content so far, certain patterns such as game progress, introduction, food, and chat rooms have already appeared. We need to overcome this and develop a completely new conceptual content that we have never seen before. This requires a more generous viewer perception of the topics covered. For diversity, linguistic and verbal violence should be tolerant in common sense to provide a foundation for securing cultural diversity. Conclusions - In this study, we tried to develop a comprehensive approach to the substitution effect of MCN. In terms of academic achievement, the PPM model is used to enhance the utilization of media and broadcasting. Practical implications are to provide an analytical framework for verifying alternative or complementary effects when viewers switch to MCN.

• Corrosion Science and Technology
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• 제17권2호
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• pp.68-73
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• 2018

Substitution of hip and knee joints by CoCr alloys is in great demand due to their high wear resistance and good biocompatibility. Understanding of tribocorrosion in joint replacements requires study of variables such as coefficient of friction and the choice of a proper corrosive medium in wear-corrosion tests carried out in the lab. The objective of this study was to characterize tribocorrosion behaviour of CoCr alloy with low (LCCoCr) and high carbon (HCCoCr) contents in several corrosive media: NaCl, Phosphate Buffer Solution (PBS), and PBS with hyaluronic acid (PBS-HA). Tribocorrosion tests were carried out on a pin-on-disk tribometer with an integrated electrochemical cell. A normal load of 5N was applied on the alumina ball counterpart at a rotation rate of 120 rpm. Coefficient of friction (COF) was measured and tribocorrosion behaviour was characterized by in situ application of electrochemical techniques. HCCoCr alloy immersed in PBS-HA showed the best tribocorrosion behaviour with the lowest COF. In this case, in situ measurement of corrosion potential and the impedance data under wear corrosion process showed an active state while passive film was continuously destroyed without possibility of regeneration.

• 스마트미디어저널
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• 제5권4호
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• pp.103-110
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• 2016

본 연구는 유사 목적을 가진 제품들을 형태적 특성에 따라 분류하고, 기능적 유사성을 기반으로 범주화하여 전형성 추출함으로써 기구디자인 개발 시, 개발방향의 기준 마련에 목적을 둔다. 전형성 추출을 위한 본 연구의 표본영역은 선험 사례연구와 전문가자문을 통해 팬던트형과 천정부착형으로 제한을 두고, 한국과 일본에 출시된 2015년 12월 이전 출시 제품을 표본으로 국내 주요 6개 도시 관련업무 종사자 및 전공자를 대상으로 조사를 실시하였다. 조사는 형태적 분류를 위한 1차 조사와 전형성 추출에 관한 2차 조사, 형태적 디자인속성 분류에 관한 3차 조사로 이루어졌으며, 기능 및 형태적 분류와 조형원리를 기준으로 디자인 속성을 도출하고 개별 요소를 추출함으로써 디자인 가중치 측정에 대한 향후 연구의 기반을 마련하고자 하였다. 연구결과의 산업적 적용으로 광원 대체로 인한 조명기구 시장변화에 디자인기술의 효율적 역할 정립과 기업의 연구개발 및 조명기구관련 제품디자인 타입 변화 가속화에 신속한 대응방향 제시 효과를 기대할 수 있다.

• Plant Biotechnology Reports
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• 제5권2호
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• pp.127-134
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• 2011

The biotransformation potential of cell suspension cultures generated from Withania somnifera leaf was investigated, using withanolides, i.e. withanolide A, withaferin A, and withanone as precursor substrates. Interestingly, the cell suspension cultures showed inter-conversion of withanolides, as well converted to some unknown compounds, released to the culture media. The bio-catalyzed withanolide was detected and quantified by TLC and HPLC, respectively. There is noticeable conversion of withanolide A to withanone, and vice versa though at a lower level. The type of reaction of this biotransformation appears to be substitution of 20-OH group to 17-OH in withanolide A. In this paper, we present for the first time the possibility of biotransformation by inter-conversion of withanolides of pharmacological importance through cell suspension culture of W. somnifera. The possible role of putative cytochrome $P_{450}$ hydroxylases is implicated in the conversion.

• 기술혁신학회지
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• 제1권1호
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• pp.96-105
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• 1998

Electronic cash affects central bank in many areas, in particular regarding the issuance of money, supervision of cashless payments, supervision of the banking system and monetary policy. The effects of electronic cash on central bank policies, the security and integrity of the payment system, and naturally also on single sector such as company engaged in the transport of money and valuables, depend mainly on the extent to which the new payment methods can replace cash. The possible development of electronic cash merits special attention from central banks for at least three reasons. First, central banks are concerned that the introduction of the new payment instrument should have no adverse effect on public confidence in the payment system and payment media. Second, although the substitution of electronic cash for other forms of money should not theoretically hamper central bank's ability to control the money supply, it might, however, have practial implications, at least in the long run, which need to be carefully examined. Third, because electronic cash may be used for payments of very small value, they have the potential, more than any other cashless instrument, to take over the role of notes and coins in the economy and, therefore, have implications for central bank's activities and revenues.

• 의학교육논단
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• 제11권1호
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• pp.21-33
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• 2009

The purpose of this study is to review a variety of e-learning use in medical education, and to analyze the e-learning related research in medical education, finally to discuss possibilities and limitations of e-learning in future. Subjects of this research are 46 papers published in Korean Medical Database, PubMed, MEDLIS, RISS4U. Content analysis of 46 papers have been conducted based on the period of research, research methods, research subjects, study personnel, effectiveness. The results are as follows. First, various e-learning, such as hyper-media, simulation-based medical education (SBME), game-based learning, web-based learning, computer-based test (CBT) are implemented in medical education. Second, 35 research (76.1%) has verified the positive effect of e-learning. Third, in the case of Korean studies, experimental studies (46.2%) in a short period (46.2%) of 50-100 people (42.3%) to take the most. As a result, it is reported a lack of theoretical discussion and insight on e-learning compared to foreign research. Educational paradigms are currently shifting from off-line to on-line, from traditional classroom lecture to e-learning. But e-learning is not a substitution to traditional teaching, but a matter of choice. The choice is up to medical professors and students.

• 방송공학회논문지
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• 제7권1호
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• pp.28-36
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• 2002

본 논문에서는 디지털 TV 방송에서 대화형 방송 서비스를 제공하기 위한 MPEG-4 기반 대화형 방송 시스템을 제안한다. 제안한 시스템은 ATSC(Advanced Television Systems Committee) 플랫폼 기반 데이터 방송 시스템에 MPEG-4 데이터를 저작하는 기능. MPEG-4 데이터를 MPEG-2 TS(Transport Stream)로 캡슬화하는 기능, MPEG-4 데이터를 MPEG-2 프로그램과 동기화하는 기능. MPEG-4 데이터를 MPEG-2 TS에서 역다중화하는 기능, MPEG-4 데이터를 복호화/출력하는 기능 및 IP 망을 통한 대화형 기능을 지원할 수 있도록 설계하였다. MPEG-4 기반 대화형 방송 시스템은 사용자에게 강력한 대화형 기능을 제공할 수 있으며. 데이터 방송 국제 규격인 ATSC. DVB 플랫폼(platform)을 대체할 수 있는 장점이 있다.

• Archives of Pharmacal Research
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• 제19권3호
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• pp.173-177
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• 1996

The Pneumococcus, Streptococcus pneumoniae, has an ample polysaccharide (PS) capsule that is highly antigenic and is the main virulence factor of the organism. The capsular PS is the source of PS vaccine. This investigation was undertaken to optimize the culture conditions for the production of capsular PS by type 4 pneumococcus. Among several culture media, brain heart infusion (BHI) and Casitone based medium were found to support luxuriant growth of pneumococcus type 4 at the same level. Therefore in this study, the Casitone based medium was used to study optimization of the culture condition because of BHI broth's high cost and complex nature. The phase of growth which accomodated maximum PS production was exponential phase. Concentrations of glucose greater than 0.8% did not enhance growth or PS production. Substitution of nitrogen sources with other resources or supplementation of various concentrations of metal ion (with the exception of calcium, copper, and magnesium ions) had adverse effects on growth and PS production. On the other hand, low level aeration and supplementation of 3 mg/l concentration of asparagine, phenylalanine, or threonine were beneficial for increased PS production. The synergistic effect of all the favorable conditions observed in pneumococcal growth assays provided a two-fold cumulative increase in capsular PS production.

• 한국실내디자인학회논문집
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• 제19권1호
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• pp.208-216
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• 2010

The design hotel where new life styles of users were created and the exchange of one's identity and the culture was executed was employed the interaction design which considered the attendance and experience of users as the important motives. This study is to discuss on the relationship between the design hotel and interaction design, and to compare and analyze the differences in the expression methods of them. It was concluded that the design hotel had a close relation with the properties of information supply, amusements, narrative, personalization, and social exchange in the interaction design, and it mainly used the digital media of non-material, the juxtaposition of strangeness, the change of structure, substitution of values, appropriation of hybrid as a means of its expression. In addition, it was revealed that the properties above did not simply apply to an open space but were connected as a dominant-subordinate relationship into one subject. It is expected that the field of interaction design in the design hotel will be expanded due to the spread of digital technology and its role and importance will be increased. Therefore, it is thought that the study to provide the development of a variety of contents of design hotel should be kept through the study of organic relation between different subjects, avoiding the indiscriminate use of the contents.