• Polymer(Korea)
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• v.34 no.3
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• pp.274-281
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• 2010

In this study, PEG-PLA(or PLGA) amphiphilic di-block copolymers were synthesized by ring opening polymerization of D,L-lactide(or glycolide) and applied to polymeric micelle system for solubilization of a rosiglitazone as diabetes drug. The drug could be efficiently loaded into the polymer micelle by solid dispersion technique, and the drug-loaded micelles were characterized and evaluated as a drug delivery carrier by fluorescence spectrometer, DSC, and DLS measurements. The colloidal stability of drug loaded micelles in aqueous media could be enhanced by addition of 2-hydroxy-N-picolylnitinamide as a hydrotropic agent. The polymer micelles also showed biocompatible and nontoxic properties in vitro cell viability using MTT assay, and the drug loaded micelles were observed to be more effective than free drug for decreasing glucose in blood of rats.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.777-787
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• 2020

With the development of the Internet and the spread of mobile devices, the online market is growing rapidly. As the number of customers using online shopping malls explodes, research is being conducted on the analysis of usage behavior from customer data, personalized product recommendations, and service development. Thus, this paper seeks to analyze the overall process of online shopping malls through process mining, and to identify the factors that influence users' purchases. The data used are from a large online shopping mall, and R was the analysis tool. The results show that customer activity was most prominent in categories with event elements, such as unconventional discounts and monthly giveaway events. On the other hand, searches, logins, and campaign activity were found to be less relevant than their importance. Those are very important, because they can provide clues to a customer's information and needs. Therefore, it is necessary to refine the recommendations from related search words, and to manage activity, such as coupons provided when customers log in. In addition to the previous discussion, this paper proposes various business strategies to enhance the competitiveness of online shopping malls and to increase profits.

• Journal of the Economic Geographical Society of Korea
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• v.7 no.2
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• pp.297-313
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• 2004

This study, based on an ethnographic field-research in Hwangryong marketplace at Jangsung, explores the transformational process of local community and local marketplace from the end of the 19th century. I attempt to use methodology of oral statement and memory. In socio-economic, political and cultural sence, Hwangryong market which made the 18th century was central place of Jangsung. It was famous of cattle marketplace from the end of Lee Dynasty. The heyday of Hwangryong market is vitalized in the ruling of Japan. Japanese government collect tax and agricultural products through this marketplace. After independence of 1945, the economic function of it was weakened, but the other side political function was strengthened. The socio-economic and cultural status of this market was revitalized after the end of Korean war notwithstanding trial of moving of marketplace. But peasant migration and mechanization of agriculture from the end of 1950' had been brought about a critical moment to Hwangryong marketplace as cattle market. The opening of Honam express road at 1973 was decisively weakened socio-economic, cultural function and role of this marketplace. Consequently, Hwangryong marketplace was transformed small local market. The identity of cattle marketplace was rarely remained in recent. This inclination will not be stopped if not linking to local festival or invention of local specialities.

• Korean journal of communication and information
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• v.70
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• pp.132-164
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• 2015

The formation of knowledge of the people of Korean society is the social practices of collective subjectivity. Subjectivity is the truth of the self, which is incessantly created, questioned and modified in the milieu of self-reflection. In an attempt to examine the hermeneutics of the subject of Korean society, a conceptual framework is proposed, which, with the notion of life embedded, consists of a historical sequence of the popular, minjung, multitude, people and community. The period of 1960s saw the ambiguous mass of lifes floating, the individual with his/her own interior world of consciousness emerge. The ideological solidarity is formed in the the next two decades, in contestation with immediate and physical threatening such as poverty and dictatorship. The democratization of Korean society and the global expansion of neoliberal regime gave a re-birth of multitude and people which is characterized with their pursuit of the co-existence and co-realization of singularity and universality on the ethical principle of the open and communicative radicality.

• Journal of The Korean Association For Science Education
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• v.32 no.4
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• pp.604-624
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• 2012

This study aims to design a framework for analyzing group argumentation in terms of participants' interaction. Regarding the current group argumentation setting as argumentation on socio-scientific issues within participants who have had limited experience on group argumentation, the analytical framework was designed to explain (1) what was each participant's role on group argumentation, (2) how these roles were changed within each time of argumentation, and (3) how the patterns of interaction were changed through seven times of a series of argumentation on socio-scientific issues. Based on the literature review on analytical framework of argumentation in science education including the works on the structure of argumentation, the discourse formation through interaction, and the linguistic approach on participants' interaction, the current research framework was built. Showing the results of applying the designed framework on group argumentation as an example, strength of using the current designed framework was discussed.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.11a
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• pp.21-22
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• 2009

최근, 헵타메틴 시아닌색소(heptamethinecyanine)는 그 적용 범위가 넓기 때문에 많은 연구자들의 관심을 받고 있다. 특히, photo-sensitizers, dye lasers, optical recordings와 storage media 등 다양한 분야에 적용이 가능하다. 헵타메틴 시아닌색소의 주된 특징은 polymethine 사슬에 연결된 cyclohexene 고리에 의하여 근적외선 부근에서 흡수가 이뤄진다는 것이다. 근적외선 색소의 흡수 특성을 HOMO와 LUMO 에너지 전위를 사용하여, 수치화 함으로써 분자간, 분자내 상호작용을 분석 할 수 있다. 따라서, 본 실험은 헵타메틴 시아닌 색소의 치환체에 따른 전기화학적 특성을 순환 전압-전류법(Cyclic voltammetry)과 분자 모델링을 통하여 HOMO와 LUMO의 에너지 준위를 구하고, 치환체 효과가 헵타메틴 시아닌색소에 미치는 전기화학적 특성을 UV-Vis와 계산으로부터 얻어진 에너지준위를 분석하고자 한다. 본 실험에 사용된 Uv-Vis 스펙트럼 측정은 Agilent 8453 UV-Vis spectrophotometer를 사용하였고, 전기화학적 분석 방법인 순환 전압-전류법은 Versa STAT 3 (Princeton allied research in USA)를 사용하였다. 순환전압-전류법의 측정은 Acetonitrile 용액에 $TBAPF_6$ (Tetrabutylammonium hexafluorophosphate)를 전해질로 하고, Ag/$Ag^+$을 기준전극으로 사용하여 주사 속도를 50mV/s로 하여 측정 하였다. 치환체에 의한 영향을 알아보기 위하여 분자구조 최적화 모델링을 사용하였다. 3차원 분자입체 특성 및 에너지 준위 상태는 Materials studio 4.2를 사용하여 특성을 예측 하였다. 본 연구에서는, 헵타메틴 시아닌 색소의 기본 골격에 각기 다른 치환체를 치환 시켜 치환체에 의한 영향을 전기화학적인 방법인 순환 전압-전류법(Cyclic voltammetry)와 분자 모델링 방법을 사용하여, HOMO와 LUMO에너지 준위 값을 구함으로써 치환체에 의한 영향을 알아보았다. 치환체로는 Dye 1과 Dye 2로 치환된 헵타메틴 시아닌 색소를 사용하였다. 이렇게 얻어진 HOMO/LUMO 에너지 준위 값으로부터 이온화 에너지($I_p$)와 전자 친화도($E_a$) 또한 구할 수 있는데, $I_p$와 $E_a$는 분자 오비탈과 전자전이에 관련된 값들이고, 이는 계산을 통하여 얻을 수 있다. 순환 전압-전류법의 계산 방법은 봉우리 전위(peak postential)와 (onset potential)방법이 있는데, 이 계산을 통한 전위 값들이 봉우리 전위 계산 방법이 onset potential 방법에 비하여 작은 전위 값으로 나타난다. 하지만 이 두 가지 방법 모두 현재 순환 전압-전류법을 사용하여 HOMO/LUMO 에너지 준위를 측정하는 방법에 쓰이고 있으며, 어떠한 계산 방법이 더 정확하다고는 말 할 수 없지만, 본 실험 결과를 통하여 비교 분석한 결과 onset potential 계산 방법이 봉우리 전위 계산 방법에 비하여 정확하다고 판단된다. Dye 1과 Dye 2를 순환 전압-전류법으로 측정한 결과 각기 다른 전위를 나타내고 이것을 계산을 통하여 정량화하면 Dye 2가 Dye 1에 비하여 높은 전위 값을 갖음을 알 수 있는데, 이것은 ethyl 에 비하여 surful 원자의 전자공여성이 더 크다고 할 수 있다.

• Journal of the Korean earth science society
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• v.38 no.1
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• pp.91-104
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• 2017

The purposes of this study were to analyze high school students' understanding about the Earth system and systems thinking process, and to develop science writing programs designed to assess students' understanding about themes of Earth Science such as global warming, volcanoes, and desertification. A total of 8 $11^{th}$ grade students from general high schools participated in the writing program and draw the causal maps. The methods of this study are as follows. First, DAET-C was used to investigate the way of students' understanding about the Earth systems. What the students' best understood was the component of the Earth systems followed by the interaction of the Earth systems and the scientific literacy of Earth science. Second, feedback circulations on the causal maps were found in four students in global warming section, one student in volcanic eruption section, and four students in desertification section, which means that systems thinking was not largely employed by the students. Consequently, the student participants understood that the global change was happening in correlation with complex concepts and factors, but they were short of using systems thinking in their science study. Therefore, the result of this study suggests that more studies be conducted to develop systems thinking in Earth Science learning through science writing programs.

• Journal of Adhesion and Interface
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• v.11 no.2
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• pp.41-49
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• 2010

Furan-containing epoxide monomers (8, 9) were designed and synthesized as carbon-neutral, environment-friendly adhesion material. Bicyclic skeleton were constructed using the Diels-Alder reaction of furan and methyl acrylate, both readily accessible starting material from a biomass via bio-refinery process. After reduction of ester functionality, resulting hydroxyl moieties were coupled to epichlorohydrin to provide the epoxy-functionalized furanic monomers (8, 9). The structure of new furanic monomers was confirmed by $^1H$ and $^{13}C$ NMR spectroscopy. As UV-curable monomers, basic properties such as UV curing time and the extent of UV curing were evaluated by photo DSC. Photo-curing shrinkages were measured by linear variable differential transformer transducer (LVDT) and the effect of molecular structure on shrinkage was considered. In addition, new synthetic compounds showed the shear strength over 3 MPa when they were photo-cured between polycarbonate plates, which indicates these compounds are feasible to use as photo-curable adhesive materials.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.145-152
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• 2009

Domestic Kori-1 MCR was partially modified in 2007 and will be renovated entirely in 2013. Digital devices partially replacing original analog devices have been introduced and standard alone computer systems such as SPDS have been integrated into the plant computer. Upgrading KSNP's MCR based on the ditalization is planned for 2015. However, the site engineers and operators are reluctant to the advanced systems. Therefore, a prototype for the KSNP's advanced MCR has been developed to increase the acceptance level of the operators and field engineers and also, to evaluate user interfaces and I&C architecture. For enhancing support of the operators' work, a P&ID based display system composed of multi-layers, which are linked through a context sensitive menu each other, has been adopted. The $1^{st}$ layer displays a simplified P&ID, the $2^{nd}$ layer control related diagrams such as controllers and logic diagrams, the $3^{rd}$ layer trends, etc. The end point view of MCR for KSNP is also suggested considering reliability and operability of the digital systems. Additionally, modernization strategies over the overhaul periods, that do not have much impact on operation and configuration efforts are suggested.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.612-619
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• 2011

Lanthanide(III) complexes of 1,2-diphenyl-4-butyl-3,5-pyrazolidinedione(phenylbutazone, PB) have been synthesized and characterized by elemental analyses, molar conductance measurements, IR, UV-Vis. and NMR spectra. The spectral data reveal that the PB acts as a bidentate and mono-ionic ligand coordinating through both the carbonyl oxygens of the pyrazolidinedione ring. The molar conductance data suggest that the complexes are non-electrolytes. The thermal behaviour of the complexes was studied by TG and DTG in air atmosphere and the results provide information about dehydration, thermal stability and thermal decomposition. The final products are found to be the corresponding metal oxides. The thermodynamic parameters and kinetic parameters were evaluated for the dehydration and decomposition stages. The negative entropy values of the decomposition stages indicate that the activated complexes have a more ordered structure than the reactants and that the reactions are slower than normal. Based on these studies, the complexes have been formulated as $[Ln(PB)_3]{\cdot}5H_2O$(Ln=La and Ce) and $[Ln(PB)_3(H_2O)_2]{\cdot}2H_2O$(Ln=Pr, Nd and Sm).