• Polymer(Korea)
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• v.37 no.4
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• pp.533-538
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• 2013

Sodium chloride is present in our body fluids, and the blood contains approximately 0.9 wt% salt, which plays an important role in maintaining the osmotic pressure. However, the amount of salt intake has consistently increased, and an excessive intake can be the cause of high blood pressure, etc. In this study, it was investigated in vivo and in vitro whether biocompatible ionic polymers with K or Ca ions can be replaced by Na ions through an ion exchange process to be excreted. Among the polymers, Ca-polystyrene sulfonate, K-polystyrene sulfonate, Ca-carrageenan, and Ca-tamarind had an excellent Na exchange ability in the body temperature, simulated gastric fluid and also simulated intestinal fluid. The mechanism of Na removal by absorption and excretion without changing food taste in the mouth through the insolubility properties of these polymers is expected to be a solution for the current problems related with excess sodium intake.

• Korean Journal of Social Welfare Studies
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• v.49 no.1
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• pp.335-374
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• 2018

It is anticipated that the introduction of ICT to street-level welfare administration will smoothen communication processes between frontline officials and recipients by intensifying welfare information sharing and distribution. However, through a case study of ICT-mediated street-level welfare administration in South Korea, this article claims that ICT can deteriorate frontline official-recipient relationship into more distrustful and disempowered directions. This study demonstrates that ICT tends to replace face-to-face rapport building between officials and recipients with mechanical checking and complaining processes. ICT-based welfare administration can also disempower the autonomous interactions of street-level actors by surveiling every working step of frontline officials and the daily lives of recipients. Through an investigation into street-level bureaucracy in an information society, this study criticizes the dehumanization tendency of ICT-mediated human services and raises a question in the roseate vision on social welfare informatization.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.209-219
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• 1997

This investigation was designed to analyze the degree of dental compensation according to horizontal components of craniofacial skeleton and to investigate correlation between dental compensation and craniofacial pattern in skeletal class III malocclusion. The material selected for this study consisted of standard lateral cephalogram of 59 subjects in normal occlusion group, 91 subjects in mild skeletal class III malocclusion group and 58 subjects in severe skeletal class III malocclusion group. The mild skeletal class III malocclusion group was divided into two groups, one was class III malocclusion without anterior crossbite group and the other was class III malocclusion with anterior crossbite group. The data were analyzed by Quick-ceph image program. The results were as follows. 1. Mild skeletal class III malocclusion without anterior crossbite group showed the most labial inclination of upper incisors, followed by severe skeletal class III malocclusion group and mild skeletal class III malocclusion with anterior crossbite group, the Latter showing the least. The amount of lingual inclination of lower incisors was the largest in severe skeletal class III malocclusion group, and there was no statistically significant difference between mild skeletal claw III malocclusion without anterior crossbite group and mild skeletal class III malocclusion with anterior crossbite group. 2. There were little differences in vertical skeletal structure between mild skeletal class III malocclusion without anterior crossbite group and mild skeletal class III malocclusion with anterior cwssbite group, they showed statistically significant differences in the upper incisors measurements. 3. The measurements of lower incisors in mild skeletal class III malocclusion without anterior crossbite group and upper incisors in mild skeletal class III malocclusion with anterior crossbite group represented a high correlation with skeletal structure. Especially, ∠IMPA and ∠FMIA of lower incisor measurements, and ∠U1-FH ∠U1-SN of upper incisor measurements showed high correlation with skeletal structure in each group. 4. ∠IMPA and ∠FMIA of lower incisor measurements showed high correlation with skeletal structure in all groups. ∠U1-FH, ∠U1-SN and U1-facial plane(mm) of upper incisor measurements represented higher correlation with skeletal structure than any other upper incisor measurements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.333-340
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• 2014

We analyzed pedestrian preference and features of preferential space by MDS (Multi Dimensional Scaling). As the result, features of pedestrian space in dimension 1 could be interpreted as "Segregation of Pedestrian and Vehicle", and features of pedestrian space in dimension 2 could be read like "Natural-City". And as a result of vector analysis about preferential of pedestrian, a pedestrian mall between housing complex, pedestrian space in pocket park, pedestrian space in neighborhood park, and pedestrian space around public facilities was the best preferential space. On the other hand, pedestrians tended to dislike pedestrian space between detached.

• Journal of Korean Society of Transportation
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• v.15 no.2
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• pp.7-23
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• 1997

본 연구의 목적은 설문조사를 통해 주민들이 실정에 맞는 거주자우선주차제의 실행 요건을 결정하는데 있다. 연구의 구성은 제2장에서 거주자우선주차제의 이론적 배경을 검토 하고, 제3장에서는 실행요건의 결정을 위한 연구분석의 틀을 제시하며, 제4장에서는 설문조 사의 방법과 조사내용에 대한 분석결과를 제시한다. 마지막으로 제5장에서는 결론과 정책건 의로 맺음한다. 이론적으로 분석결과 거주자우선주차제는 주차수요관리와 주차장공급촉진이 라는 2원적인 목표를 내재하고 있는 것으로 나타났다. 그결과 허가요금, 시행시간대 등의 실 행요건을 결정하는데 있어서 다양한 외부요인들을 고려하여야 할 필요가 있으며, 외부요인 들은 거주자들의 사회경제적 특성, 주거환경적특성, 주차행태적 특성, 기타특성 들로 구성된 다. 실행요건을 결정하기 위해 주민들에 대한 설문조사를 실시하였고 그 분석결과는 다음과 같다. 1) 요금수준 결정시 차고지 공급 목적일 경우 높은 수준의 요금을 부과하되 지역적 소득수준을 감안 하여야 하며, 목적이 수요관리에 있을 때는 외부인에 대한 규제만 하면 되 기 때문에 주민들에게는 무료이거나 가능한 낮은 요금을 징수하는 것이 바람직하다. 2) 공 간적 범위는 주민들의 근거리주차 선호 때문에 블록단위 또는 세가로를 중심으로 시행하되, 집앞돌폭이 4m 미만이거나 8m 이상일 경우에는 공간적 범위를 넓게 잡는 것이 바람직 할 것이다. 3) 주차면 배정은 독점적 사용권을 부여하는 방식이 공공재의 사유화라는 부작용 및 주차면의 비효율적 사용이라는 측면이 있기 때문에 가능한 공동이용방식을 채용함이 바 람직 한 것으로 나타났다. 4) 외부인 주처허가는 전용주택가 지역에서는 허용하여도 그리 큰 문제는 없을 것이나, 외부인 주차수요가 많은 지역에서는 무조건적 허락보다는 요금지불, 주차확인증과 같은 제도적 보완을 통해 허용해야 한다. 5) 시행시간대 결정시 전용주거지역 에서는 야간만 실시하여도 문제가 없으나 그외 지역에서는 주차수요를 고려하여 주간 또는 전일로 시행할 필요가 있다. 특히 주차문제가 하루종일 발생하는 경우와 출퇴근시 주차문제 가 많은 곳에서는 하루종일 시행할 필요가 있다. 그러나 차고지 확보율이 지나치게 낮은 곳 에서는 야간시 주민반대에 부디칠 가능성이 크기 때문에 차고지 여건이 개선될 때 까지는 시행을 보류할 필요가 있을 것으로 판단된다.

• KDI Journal of Economic Policy
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• v.35 no.4
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• pp.95-136
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• 2013

Using Workplace Panel Survey of 2005, 2007 and 2009 waves, this study estimates the effects of trade unions on employment and the proportion of irregular workers, short-term and part-time workers, and agent temporary and outsourced workers. While the estimation result shows that the percentage of hired workers increases under union presence, these results seem to be contaminated with bias because the differences between unionized firms before union establishment and non-unionized firms are not completely controlled even after adjusting for observed characteristics. Meanwhile, unionized firms and non-unionized firms with grievance procedures employ higher proportion of irregular workers. The proportion of short-term and part-time workers increases only when they are entitled to join trade unions. These imply that the rise in the percentage of irregular workers due to unions and grievance procedures is attributed to the increase in the percentage of agent temporary and outsourced workers. Also, when short-term and part-time workers are allowed to join the union, the firm replaces agent temporary and outsourced workers with short-term and part-time workers, so that the proportion of irregular workers do not change.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.634-640
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• 2008

The purpose of this study is to clarify the physiological effects of Shinrin-yoku (taking in the atmosphere of the forest of forest bathing). The subjects were twelve male university students ($21.6{\pm}2.1$ years old). On the first day, six subjects were sent to a forest area, and the others to a city area. On the second day, the subjects were sent to the opposite areas for a cross check. The subjects were seated on chairs and viewing the landscapes of their given areas for 15 minutes. HRV (Heart Rate Variability) and diastolic blood pressure were used as physiological indices. Diastolic blood pressure and LF/(LF+HF) components of HRV in the forest area were significantly lower than in the city area. And HF power components of HRV in the forest settings were significantly enhanced than in city settings. In conclusion, the results of the physiological measurements show that Shinrin-yoku was able to effectively relax people in both mind and body.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.120-120
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• 2018

반도체 소자나 디스플레이 패널 제조 공정에 가장 많이 사용되는 진공 펌프인 터보 분자 펌프는 오일을 사용하지 않고, 설치 방향이 자유로우며 넓은 작동 압력 영역을 가지고 있어서 고가임에도 불구하고 점점 더 사용 영역을 넓혀 가고 있다. 상하의 두 곳에 회전축을 지지하는 베어링이 필요한데, 기계식 금속 베어링을 채용하는 경우에는 반드시 윤활유를 공급해 주어야 하고, 고온, 부식성 또는 산화성 가스의 배기 시에는 퍼지 가스로 비활성인 질소나 알곤등을 이용하여 보호를 해주어야 한다. 반면, 자기 베어링을 채택한 모델은 윤활의 걱정에서 자유로울 수 있기 때문에 채용이 늘어나고 있다. 동일극의 반발력이나 반대극의 인상력을 이용한 구조를 갖게 되는데 갑작스러운 입구 쪽 압력의 증가 시에는 자석 끼리 부딪치는 일이 발생하고 이로 인해서 로터 모듈 전체에 큰 손상을 갖게 되므로 한 곳 정도에 비상용 터치 다운 베어링을 기계식으로 윤활제 없이 설치하기도 한다. 기본적으로 자기 베어링 방식은 로터 모듈의 부상과 제어를 위해서 3축 또는 5축 제어를 하게 되는데 여기에는 전자석의 전류를 미세하게 조정하여 피드백 하는 시스템을 활용하기 때문에 외부에서의 자기장이 일정값 이상 침투하게 되면 제어 회로의 기능에 문제를 일으키게 된다. 또한 축 방향에 수직인 자기장의 강도가 높아지면 고속으로 회전하는 금속 블레이드가 자속을 자르게 되므로 표면에 와전류가 발생하여 문제가 된다. 터보 분자 펌프는 회전자와 고정자 간격이 1 mm 이내로 작아서 약간의 진동이라도 발생하면 회전자와 고정자 간에 충돌이 일어나고 이는 곧 파손으로 이어진다. 그림 1에는 파손 원인 분석을 위한 회전자 모듈의 수치 해석용 모델의 일부를 나타내었고, 그림 2에는 실제로 외부 자기장에 의한 파손이 발생한 사례의 자기 베어링 모듈의 사진을 나타내었다. 본 발표에서는 외부 자기장의 형태에 따라 제어 자기장에 미치는 영향을 CFD-ACE+(ESI corp)를 활용하여 해석하였다.

• Informatization Policy
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• v.22 no.2
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• pp.19-34
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• 2015

Due to rapid convergence trends in the digital pay TV market, differentiation among the competing medias decreases and substitutability is increasing. The current study aims to explain the effect of service substitutability among competing media on the size of domestic digital pay TV subscribers. For the analysis, the Lotka-Volterra model, an ecological competitive diffusion model, was used to obtain the basic model for a simulation study. A simulation was performed by adjusting independent variables of substitutability to estimate the size of subscriber for particular media. The relationship between the digital cable TV and the IPTV is identified as a predator-prey relationship and the digital cable TV is found to be superior to the IPTV. The simulation results showed that the increase of convergence and substitutability result in the decrease of the entire media market. Especially, the IPTV is estimated to face the greatest loss in this context.

• The Korean Journal of Archival Studies
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• no.52
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• pp.171-212
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• 2017

Music has been created and played in various environments over a long time, with each piece having distinct sentiments and stories. Different people can have varying interpretations of one song depending on their viewpoints shaped by personal experiences and attitudes. In fact, the audience's understanding may differ greatly from the songwriter's intended message. Knowing this, music can serve as a reflection of one's contemporary sentiment. In the works of art such as music, the creator's intention becomes the background of the work or, sometimes, the main meaning. However, given that popular music is often under the control of companies and distributors and influenced by "capital," creators are required to adjust to mainstream preferences and, therefore, cannot fully express themselves in their music. On the other hand, indie music allows creators to pursue their own music given its "independence" from capital. With this, this study aims to collect and analyze data on the activities that Korean indie bands carry out, and examine their meaning and significance in society.