• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.5
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• pp.40-50
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• 2016

Energetic plasticizers containing explosophore groups such as $-NO_2$, $-ONO_2$, and $-N_3$ group are susceptible to impact, shock, heat, etc, finally deteriorating the insensitivity of PBXs. In this study, in an attempt to investigate the feasibility of replacing sensitive explosophore groups to fundamentally inactive but potentially (latent) energetic fluorine group which was known to have an exothermic thermite reaction with aluminum, nano-aluminum/fluorinated polyurethane binders were prepared by simultaneous polyurethane and catalyst-free azide-alkyne click reaction in the presence of nano-aluminum. Thermal characteristics of nano-aluminum/fluorinated polyurethane binders were monitored by using DSC with high pressure crucible pan.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.229-230
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• 2008

본 연구에서는 자동차 사고나 뇌졸중 등에 의해 경추 이하의 마비나 손, 발 등의 움직임은 자유롭지 않은 사람들의 컴퓨터 사용을 돕고자 손이나 발을 이용하지 않고 머리의 움직임과 눈의 깜박임만으로 컴퓨터 마우스 제어가 가능한 장치를 제안하였다. 마우스의 좌우, 상하 이동은 자이로센서를 이용하여 머리의 움직임으로 유발하고, 클릭과 더블 클릭은 광 센서를 시야를 방해하지 않는 위치에 장착하여 감지할 수 있도록 하였다. 제안한 장치의 클릭과 더블 클릭의 인식율은 사용자가 몇 번의 학습으로 높일 수 있었고, 반응속도는 기존 마우스의 이동 속도와 비교해 볼 때 큰 차이는 없었다. 마지막으로 종합적인 평가를 위해 마우스 이동과 클릭을 동시에 수행하였을 경우에는 정확도가 $80{\sim}90%$ 정도로 기존 마우스보다는 낮았다.

• Polymer(Korea)
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• v.39 no.1
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• pp.165-168
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• 2015

Thermoresponsive polymers were successfully synthesized by a combination of atom transfer radical polymerization (ATRP) and Cu(I)-catalyzed 1,3-dipolar cycloaddition of azide and alkynes (click chemistry). Poly(2-hydroxyethyl methacrylate) (PHEMA) was synthesized by ATRP, followed by introduction of alkyne groups using pentynoic acid, leading to HEMA-alkyne. Homopolymers having secondary amine groups, tertiary amines with hydroxyethyl and hydroxypropyl groups were synthesized by adding 2-azido-N-ethyl-ethanamine, 2-[(2-azidoethyl)amino]ethanol, and 2-[(2-azidoethyl)amino]propanol, respectively, to the PHEMA-alkyne backbone using click chemistry. Molecular weight (MW), molecular weight distribution (MWD), and click reaction efficiency were determined by gel permeation chromatography (GPC) and $^1H$ NMR spectroscopy. The transmission spectra of the 1.0 wt% aqueous solutions of the resulting polymers at 650 nm were measured as a function of temperature. Results showed that the lower critical solution temperature (LCST) could be easily controlled by the length of the hydroxyalkyl groups.

• Polymer(Korea)
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• v.33 no.1
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• pp.67-71
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• 2009

The stitching method for the synthesis of $Fr\acute{e}chet$-type dendrimers was elaborated using click chemistry between an alkyne and an azide. The core building block, 4,4'-(3,5-bis(azidopropyloxy)benzyloxy)bisphenyl, was designed to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne-dendrons. The synthetic strategy involved an 1,3-dipolar cycloaddition reaction between an azide and an alkyne-functionalized $Fr\acute{e}chet$-type dendrons in the presence of Cu(I) species which is known as the best example of click chemistry.

• The Journal of the Korea Contents Association
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• v.20 no.3
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• pp.254-266
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• 2020

The purpose of this study is to analyze the influence of the type of recommender system on consumer's perceived benefit and privacy risk. The result showed that the perceived usefulness and intension to click was high in the order of Hybrid-filtering, Bestseller, and SNS-based system. Privacy concern was high in order of SNS-based system, Hybrid-filtering, and Bestseller. Moderating effects of perceived personalization on the type of recommender system and perceived usefulness were significant. Finally perceived usefulness had positive effect, and privacy concern had negative effect on consumer's intension to click. This study has significant implications for digital marketing bt comparing consumer responses according to the type of recommended service. The result of this study can be helpful for providing and developing future recommender service.

• Polymer(Korea)
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• v.36 no.3
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• pp.295-301
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• 2012

Efficient stitching methods for the synthesis of Fr$\acute{e}$chet-type dendrimers with linear PEG units at a core were elaborated. The synthetic strategy involved an inexpensive 1,3-dipolar cycloaddition reaction between an alkyne and an azide in the presence of Cu(I) species which is known as the best example of click chemistry. The linear core building blocks, two diazido-PEG units, were chosen to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne-dendrons. These two building blocks were employed together with the alkyne-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize two kinds of Fr$\acute{e}$chet-type dendrimers with different linear core units.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.701-706
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• 2009

We proposed the device to control a computer with only a head and eye blinks so that disabilities by car accidents can use a computer. Because they have paralysis of their upper extremities such as C4~C5 paraplegics and cerebral palsy, they cannot efficiently access a general keyboard/mouse not using hands and foots. The cursor position was estimated from a gyro-sensor which can measure head movements, and the mouse event such as click/double click from opto-sensors which can detect eye blinks. The sensor was put on the proper goggle in order not to disturb the visual field. The performance of the proposed device was compared to a general optical mouse, and was used both relative and absolute coordinate in cursor positioning control. The recognition rate of click and double-click was 86% of the optical mouse, the speed of cursor movement by the proposed device was not much different from the mouse. The overall accuracy was 80%. Especially, the relative coordinate is more convenience and accuracy than the absolute coordinate, and can reduce the frequency of reset to prevent the accumulative error.

• Journal of the Korean Vacuum Society
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• v.18 no.6
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• pp.481-487
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• 2009

To control the diameter size of the carbon nanofilaments (CNFs), SF6 was incorporated in the source gases ($C_2H_2/H_2$) during the initial deposition stage. The source gases and $SF_6$ were manipulated as the cyclic on/off modulation of $C_2H_2/H_2/SF_6$ flow in a thermal chemical vapor deposition system. The characteristics of the CNFs formation on the substrate were investigated according to the different cyclic modulation processes and the substrate temperatures. By $SF_6\;+\;H_2$ flow injection during the cycling etching interval time, the diameter size of CNFs was extremely decreased. The cause for the decrease in the diameter size of the individual CNFs by the cyclic on/off modulation process of $C_2H_2/H_2/SF_6$ flow was discussed in association with the slightly enhanced etching ability by the incorporation of $SF_6$.

• 재활복지
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• v.16 no.2
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• pp.287-309
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• 2012

The purpose of this study was to determine the effect of custom seating system on upper extremity access to mouse for a child with cerebral palsy. A single-subject ABAB design was used with one 13years old participant. The measurements were response time and accuracy of mouse click in the participant's typical position and in an intervention position. The intervention position was taken by using current clinical guideline and research on promoting upper extremity movement. The intervention position was achieved through hands-on postural support to the participant's typical seating. The results of this study were as follow: first, response time was decreased in the intervention position compared with the typical seating. Second, accuracy of mouse click was highly in every phases. So further analyses were not conducted on these data. The results of this study provide empirical evidence of the positive effects of functional seating on access to mouse for children with cerebral palsy. Further research is required to confirm the positive effect of the custom seating system across other disabilities type and more subjects.

• Digital Contents
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• no.2 s.93
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• pp.70-75
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• 2001

지난 1월 4일부터 8일까지 인터넷 리서치 전문기관인 (주)아이클릭과 한겨레 닷21이 공동으로 실시한 '콘텐츠 유료화에 대한 네티즌 설문조사 결과'에 따르면 콘텐츠 유료화의 최대 현안은 역시 '콘텐츠의 질'로 조사되었다. 대부분의 네티즌들은 유료화에 대한 저항을 보였지만 '돈을 낼만한' 콘텐츠에는 돈을 내겠다는 긍정적인 반응을 보여 유료화에 대한 가능성을 확인 할 수 있었다.