• 한국시스템다이내믹스연구
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• 제11권4호
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• pp.77-96
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• 2010

Since the mid-1990s, Korea has recorded low population growth rate. Based on the figures provided by the Statistical Korea, Korea may be even confronted with decreasing trends in the total population at the end of 2010s. In addition, Korea may experience the hyper-aged society in the mid-2020s. In the depopulation era, we have to devise alternative urban management policies reflecting low and reversed trends in the urban population. It is almost certain that urban policy-makers have to deal with a new series of urban problems, even jeopardizing the continuity of urban territories. In order to minimize the negative impact derived from depopulated phenomena, they have to develop sound and sustainable urban policy alternatives. This research adopts system dynamics approaches, revealing key factors exerting significant impact on the existing urban management policies. In specific, it pays attention to major causal loops, reinforcing or balancing behavioral.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1262-1264
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• 1993

An amorphous $Se_{75}Ge_{25}$ thin film as inorganic resist for the focused ion beam lithography(FIBL) is investigated. This film offers an attractive potential alternative to polymer resists because of a number of advantages, such as the possibility of preparing physically uniform films of thickness as small as 200A and obtaining both positive and negative resist action in the same material, compatibility with dry processing, the sensitivity on optical, e-beam and ion beam exposure, the high-temperature stability, etc. In previous paper, the defocused ion beam-induced characteristics in a-$Se_{75}Ge_{25}$ film has been propose. Practically it is neccesary to know the relation with resist and source ions. For the purpose, the ion stopping power, the ion projected range and ion transmission coefficiency are studied. In this paper, the theoretically calculated values of parameters are presented and compared with theory.

• 패션비즈니스
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• 제23권1호
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• pp.127-144
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• 2019

The purpose of this study is to clarify the phenomenon and characteristics of fashion in before Orientalism by examining the environmental changes and factors of East - West cultural exchange from the 16th century to the 18th century. To this end, this study examines the development of political and diplomatic relations, the growth of economy and trade, the investment of culture and arts, and the development of industry and technology. The research method used was the analysis of previous literature research and visual data. The result were as follows; the characteristics and phenomena in fashion in before Orientalism were symbolism as a privileged whole, applying to special clothing area, variety and splendor of fabrics, change of costume design, and a trend of exotic taste. Before Orientalism, the perspective of Orient in Europe can be seen as having the positive aspects cause of developing fashion and a negative aspect coming from an incorrect understanding and a bias.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.233.3-234
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• 2003

Electroosmotic flux during iontophoresis originates due to the net negative charge of the current passing channel (pores) in skin at physiological pH (pH 7.4). Thus, the channel is permselective to cations, and this causes the convective solvent flow, from anode to cathode direction. This solvent flow facilitates the flux of cations (from anode), inhibits that of anions (from cathode), and enables the enhanced transport of neutral, polar solutes. In this work, we have investigated the effect of a series of polyethylene glycols (PEGs) with different molecular weights on the electroosmtic flow to get more detail understanding of this phenomena. (omitted)

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.111.1-111.1
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• 2010

This paper focuses on a systematic configuration of steam reforming fuel processor, particularly designed for small and medium sized hydrogen production application. In a typical integration of the fuel processor, there exist significant temperature gradients over the entire system which has negative effect on both catalyst life-time and system performance. Also, the volumetric inefficiency should be avoided to obtain the possible compactness for the commercial purpose. In the present work, the computational analysis will be performed to gain the fundamental insight on the transport phenomena and chemical reactions in the reformer consisting of preheating, steam reforming (SR), and water gas shift (WGS) reaction beds in the flow direction. Also, the fuel processing system includes a top-fired burner providing necessary thermal energy for endothermic catalytic reactor. A fully two-dimensional numerical modeling for a integrated fuel processing system is introduced for in-depth analysis of the heat and mass transport phenomena based on surface kinetics and catalytic process. In the model, water gas shift reaction and decomposition reaction were assumed to be at equilibrium. A kinetic model was developed and then computational results were compared with the experimental data available in the literature. Finally, the case study was done by considering the key parameters, i.e. steam to carbon (S/C) ratio and temperature. The computer-aided models developed in this study can be greatly utilized for the design of advanced fast-paced compact fuel processors research.

• 한국조경학회지
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• 제33권5호통권112호
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• pp.31-42
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• 2005

This study has been conducted in order to better understand a concrete and evidential disagreement that resulted from a conflict caused by the exploitation of folk village for tourism purposes. The purpose of this study was to analyze more realistically the phenomenon of the disagreement that originated from sightseeing in the hahoe folk villages by focusing on the problem between the ive groups as a potential and continual impediment to tourism. Two groups, residents and tourists, were compared in order to determine the underlying factors of the disagreement regarding exploitation of folk villages for tourism The two groups were clearly split: inhabitants of the village considered such exploitation negative, while tourists accepted it as positive. The two groups showed different understandings of the topic residents were in favor of the preservation of the physical resources, but against exposure of their private lives to the public, while tourists strongly respected the preservation of the resources of the village. A comparison of the common phenomena of disagreement between the two groups was performed, Variables that showed different responses between the two groups were loss of privacy of individual houses, verbal aggression and physical conflicts between the groups, and lack of administration. In most of the cases of disagreement, residents considered the disagreement phenomena to be more serious than tourists did except in one case: tourists placed a greater importance on the ugly view of the street market. Finally, in order to analyze the factors that impacted the level of the disagreement, a multiple regression analysis was conducted. Disagreement factors affecting tourists were verbal aggression between the groups, complaints about lodging and dining facilities, complaints about tourist facilities, and negligence of the administration in responding to requests. Among these, the most influential factor was verbal aggression between the groups. In fact, individual feelings between tourists and residents proved to be the biggest influence on the level of disagreement.

• 한국언론정보학보
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• 제32권
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• pp.169-207
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• 2006

본 논문에서는 디지털 온라인시대의 유비쿼터스 환경에 대해서 언론의 보도 내용 및 태도와 함께 일반대중들이 지니고 있는 다양한 관심이나 주관적인 성향(느낌, 견해)들에 대한 유형을 살펴봄으로써, 유비쿼터스 환경이 어떠한 특성과 의미를 보여주고 있는지를 알아보았다. 이를 위해 유비쿼터스 환경을 미디어가 어떻게 프레이밍 하였는가를 먼저 프레이밍 이론의 시각에서 살펴보고, 이러한 프레이밍이 수용자의 개인적 수준에서의 해석적 프레임으로 볼 수 있는 주관적 인식과 어떤 유사성이나 차이가 존재하는지 그 연결점을 알아보기 위해서 주관성연구를 실시하였다. 유비쿼터스 환경에 대한 일반대중들의 수용형태를 살펴본 결과, 4가지의 유형으로 분류되었는데, 제 1유형(N=11)은 긍정적 보편 주도형(Positive Universality Leading Type), 제 2유형(N=4)은 회의적 신중 선호형(Uncertain Prudence Preference Type), 제 3유형(N=3)은 미래 문화적 향유형(Future Cultural Enjoyment Type), 제 4유형(N=2)은 부정적 효과 전망형(Negative Effect View Type)으로서, 각 유형마다 독특한 특징이 있는 것으로 확인되었다. 결론적으로 수용자들은 대체로 미디어가 제시한 프레임에 의해 유비쿼터스 환경을 인식하고 있었으나, 다른 한편 확고한 주관과 정체성에 기초하여 유비쿼터스 환경을 인식하고 있어 미디어 프레임과 수용자 인식 사이의 관련성이 존재하지만 이외의 중재변인이 또한 존재하여 향후 이에 대한 탐색의 필요성이 있음을 확인할 수 있었다.

• 한국염색가공학회지
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• 제1권1호
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• pp.19-25
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• 1989

In past, dye diffusion and dyeing rate in fibers have been emphasized in dyeing phenomena. However, in the light of the properties of colloids in the surface of disperse phase and dispersion, there exist specific characters such as adsorption or electric double layer, which seems to play important roles in determining the physiochemical properties in the dyeing system. Electrostatic bonding, hydrogen bonding and Van der Waals adsorption are common in dyeing as well as covalent bonding. Particularly, electrostatic bonding is premised on the existance of ionic radicals in fibers. The present study was aimed to clarify the electrokinetic phenomena of dyeing through the role of electric double layer by ion in amphoteric fibers with different ionic effects under different pH. Spectrophotometric analysis method was used to compare dyeing condition of surface, which can be detected by electrokinetic phenomena and the inner of fibers after deceleration of dyed fibers. Nylon and wool, the typical amphoteric fibers were dyed with monoazo acid dyes such as C.I. Acid Orange 20, and C.I. Acid Orange 10. Various combinations were prepared by combining pH, temperature and dye concentration, in order to generate streaming electric potential which were measured by microvolt meter and specific conductivity meter. The results were transformed to zeta potential by Helmholtz-Smoluchowski formular and to surface electric charge density by Suzawa formular, surface dye amount, and effective surface area of fibers. The amount of dyes of inner fibers were also measured by the Lambert-Beer’s law. The main results obtained are as follows. 1. By measuring zeta pontential, it was possible to detect the dyeing mechanism, surface charge density, surface dye amount and effective surface area concerning dye adsorption of the amphoteric fibers. 2. Zeta pontential increases in negative at low pH and high dye concentration in the process of dyeing. This implied that there existed ionic bond formation in the dyeing mechanism between acid dyes and amphoteric fibers. 3. Dibasic acid dye had little changing rate in zeta potential due to the difference in solubility of dye and in number of dissociated ions per dye molecule to bond with amino radicals of amphoteric fibers. The dye adsorption of mono basic acid dye was higher than that of dibasic acid dye. 4. The effective surface areas concerning dyeing were $6.3E+05\;cm^2/g$ in nylon, $1.6E+07\;cm^2/g$ in wool fiber being higher order of wool then nylon.

• 한국대기환경학회지
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• 제19권4호
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• pp.347-361
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• 2003

Sulfur dioxide (SO$_2$), ozone, total suspended particulates (TSP) and PM$_{2.5}$ were measured at Deokjeok Island in the Yellow Sea during April 1999 to June 2000. Although the emission amount of air pollutants is quite low in this small island of 36 km$^2$ with 1.4 thousand inhabitants, there are pollutant sources such as an oil -firing power plant and a wharf for ferryboat. The island is also influenced from the emissions from the greater Seoul area in the east and from China in the west. In order to characterize the pollutant variations due to interactions between transport and local emissions. the correlation between variations of SO$_2$ and ozone was investigated. Mass and ion concentrations of TSP and PM$_{2.5}$ were examined on selected episode days of positive and negative correlations between the two gaseous species in spring and winter. The effects of transport were pronounced on the days of positive correlation in spring with higher concentrations of ozone and PM$_{2.5}$. TSP concentrations were also high on these days because of high wind speeds. On the days of negative correlation in spring, frequent fog associated with low wind speeds facilitated SO$_2$ oxidation and increased sulfate accompanied with decrease in nitrate in PM$_{2.5}$ and chloride in TSP. This latter phenomena was noticeable since it showed that chemical composition of fine particles could be significantly altered not only during the transport but also by local environment.ronment.

• 폴리머
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• 제27권4호
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• pp.275-284
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• 2003

접착성이 없는 고밀도 폴리에틸렌 (HDPE)과 나노입자 카본블랙 복합체를 대상으로 전극과의 계면 접착 향상과 고분자 가교 특성에 따른 양온도 계수 (PTC) 특성을 연구하였다. 은페이스트를 전극으로 사용하였을 때에는, 전극과 HDPE의 접착 계면 저항으로 인하여 카본함량이 45 wt% 이상에서 1 $\Omega$ 이었으나, 덴드라이트 (dendrite)된 구리 전극의 경우 HDPE와 전극간의 넓은 면적 접촉에 의한 계면 저항이 0.2 $\Omega$ 이하였다. HDPE와 은페이스트의 계면 저항의 증가로 인하여 구리 박막을 사용하였을 때보다 전체적으로 저항이 높게 나타났다. HDPE와 나노입자 카본블랙 복합체는 온도가 증가하여 HDPE의 비캣연화온도까지는 저항이 일정하게 유지하다가, HDPE의 연화점에서 증가하기 시작하여 용융점에서 극대 값을 나타내는 전형적인 PTC특성을 보여주었다. 일반적으로 HDPE의 용융점을 넘어서면 음온도 계수 (NTC) 현상이 나타나는데, 가교결합을 시킨 HDPE의 경우는, 용융점 이상에서 NTC 현상이 나타나지 않고 저항이 일정하게 유지되거나 증가하는 경향이 나타났다. 구리 (copper) 전극과 고분자와의 계면 접촉 면적을 증가시키기 위하여 크롬 (chromium)을 덴드라이트시킨 전극을 사용하여 계면 접촉 저항을 감소시켰다.