• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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• pp.1-9
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• 2009

As many new drug substances contained various aromatic rings and fluorine attached to an electron rich aromatic ring or on the meta-position, a strategy towards improvement in aromatic fluorination of these compounds is highly desirable. The introduction of fluorine-18 onto aromatic rings showed in the limited condition containing electron withdrawing group (EWG) on the para- or ortho-position to get reasonable radiochemical yield so far. No-carrier added (NCA) [$^{18}F$]fluoroarene syntheses by iodonium salts recently reported that has the potential to greatly increase the yield in systems or positions that normally not reactive enough to give sufficient yields in simple model reaction. This review describes the methodological approach towards effective aromatic fluorination by diaryliodonium salts and future prospects in an application of novel PET radiotracer.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.89.2-89.2
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• 2012

$150^{\circ}$ 이상의 접촉각을 가지는 초소수성 표면은 self-cleaning, anti-fingerprint, anti-contamination 등의 특성을 가지므로 전자, 도료, 자동차 등 다양한 산업에서 활용될 수 있다. 재료 표면의 친/소수성은 물리적 요인과 화학적 요인 두 가지 요인을 조절함으로써 제어할 수 있다. 즉, 표면의 거칠기를 크게 하거나 표면에너지를 낮춰줌으로써 초소수성 표면을 구현할 수 있다. 실리카는 자연계에 매우 풍부하게 존재하고 있으며, 생체무해하며 내구성과 내마모성, 화학적 안정성, 고온 안정성 등을 지니고 있어 박막소재로 이용하기에 우수한 특징을 지니고 있다. 이러한 실리카 초소수성 코팅층을 형성하는 방법으로 본 연구에서는 전기분무법으로 마이크로 크기의 실리카 입자로 형성된 코팅층을 형성하였다. 이러한 마이크로 구조의 표면거칠기를 더욱 높이기 위하여 금 나노입자를 부가적으로 형성시켜 마이크로-나노구조 혼성의 계층구조를 만들고자 하였다. 금 나노입자는 자외선 조사 광환원법을 사용하였고, 이러한 계층구조에 플루오린 처리를 하여 계층구조 초소수성 코팅층을 형성하였다. 계층구조를 가지는 실리카 코팅층은 물 이외에 표면장력이 낮은 용액에서도 높은 접촉각을 보였고, 이러한 코팅층의 고온 안정성과 내구성, UV 저항성 등을 조사하여 실제 응용 가능성을 검토하였다.

• Journal of IKEEE
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• v.17 no.1
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• pp.57-62
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• 2013

In this paper, we have implemented an overflow valve for EURO5 Type and the performance evaluation system based on IEEE802 protocol. On injecting a diesel oil into an engine, it is necessity for an overflow valve that can sustain an engine oil status in front of the engine. In order to evaluate the performance of overflow valve, we need the leak test system with IT. The leak test system checks the pressure, switching time and operating time.

• Child Health Nursing Research
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• v.17 no.1
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• pp.1-9
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• 2011

Purpose: The purpose of this study was to investigate the knowledge and practice level of infection managements in child guardians with respiratory infections after H1N1 diffusion of 2009. Methods: The data were collected during February and March 2010 using a self-report questionnaire. The participants were 228 child guardians. Data were analyzed using frequency, percentage, means, SD, t-test, F-test, Pearson correlation coefficients, and Cronbach's alpha with the SPSS 17.0 program. Results: Mean age of the guardians and children were 37.8 years, 4.1 years respectively. For knowledge level of respiratory infections, hand washing method had the highest score and snuffles prevention method, the lowest. For practice level for respiratory infections, environmental hygiene management had the highest score and symptom management, the lowest. Infection management knowledge and practice level had a positively significant correlation in every area. Conclusion: The results indicate the necessity of continual education on infection management, and that the most efficient timing for the education appears be for participants during their first pregnancy or after the woman has delivered her child.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.3
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• pp.240-245
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• 2013

The utilization of a fluoran leuco sensitizer, 2-anilino-6-dibutyl amino-3-methylfluoran (ODB-2), for dye-sensitized solar cells (DSSCs) was investigated through the examination of the adsorption of ODB-2 molecules onto the surfaces of porous titanium dioxide (titania, $TiO_2$) films and the photovoltaic properties of ODB-2-based DSSCs. Despite of the absence of the specific anchoring groups with titania, ODB-2 dye molecules were spontaneously adsorbed onto the titania surfaces because the lactone ring in ODB-2 was opened and changed into the carboxylic acid (-COOH) by releasing protons from the surfaces ($TiOH_2{^+}$) of titania, which consequently leads to the chemisorption reaction of ODB-2 molecules to the active sites of titania. DSSCs based on ODB-2 exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.19 V, a short-circuit current ($J_{SC}$) of $0.30\;mA{\cdot}cm^{-2}$, a fill factor (FF) of 37%, and a conversion efficiency (PCE) of 0.02%.

• Journal of the Korean institute of surface engineering
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• v.54 no.6
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• pp.357-364
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• 2021

In this study, DLC films deposited by PECVD were evaluated to the properties of super-hydrophobic by CF₄ treatment. The structure of DLC films were confirmed by Raman Spectra whether or not mixed sp³ (like diamond) peak and sp² (like graphite) peak. And the hydrogen contents in the DLC films (F-DLC) were measured by RBS analysis. In addition, DLC films were analyzed by scratch test for adhesion, nano-indentation for hardness and tribo-meter of Ball-on-disc type for friction coefficient. In the result of analysis, DLC films had traditional structure regardless of variation of hardness at constant conditions. Also adhesion of DLC film was increased as higher material hardness. Otherwise, friction coefficient was increased as lower material hardness. The DLC films were treated by CF₄ plasma treatment to enhance the properties of super-hydrophobic. And the DLC films were measured by ESEM(Enviromental Scanning Electron Microscope) for water condensation.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.625-628
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• 2020

현재 지구촌은 신종 감염병인 '코로나바이러스 감염증-19(COVID-19)로 인해 혼란을 겪고 있다. 우리나라의 경우 1만 명 이상 감염자가 발생하였으며, 사망자 역시 200여 명이 넘었다. 하지만 위와 같은 감염병을 치료하기 위한 백신은 계속 개발중에 있으며, 현재는 감염 예방 수칙으로 감염의 위험성에서 벗어나고 있는 실정이다. 또, 지구촌에 큰 혼란을 주었던 사스, 신종플루, 메르스와 같이 주로 호흡기를 통해 타인에게 전파되는 신종 감염병 출현 빈도 역시 계속 증가하고 있다. 이외에는 황사, 미세먼지에 관한 문제들로 인해 일상속에서 이뤄지는 생활 방역의 중요성이 대두되고 있는 상황이다. 본 논문에서는 생활 방역의 대표적 수칙인 마스크 착용에서 상황별 올바른 마스크 선택의 중요성을 알려주어 시민의식을 높일 수 있는 VR 연동 'Wearing a Mask' 구현에 대해 제안하고자 한다.

• YAKHAK HOEJI
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• v.42 no.3
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• pp.265-274
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• 1998

In order to attain a sustained release at targeted organs in a prolonged time which can reduce the side effects and maximize the therapeutic effect, aclarubicin (ACL) was entrap ped into liposomes of different lipid compositions using Microfluidizer, and dry liposomes were prepared by lyophilization. The dry aclarubicin-entrapped liposomes were evaluated in terms of mean particle size and size distribution, entrapment efficiency and in vitro drug release profile. The Entrapment efficiency of liposome, when the concentration of aclarubicin and lipid were 0.5 to 1.0mg/ml and $200{\mu}mol$/ml, respectively, was over 80% using Microfluidizer, in contrast to 70% of entrapment efficiency using hand-shaking method. Mean particle size and size distribution of aclarubicin-entrapped liposomes of various lipid compositions did not change considerably by the freeze drying. The range of particle size was between 80 and 200nm. Among aclarubicin-entrapped liposomes, ACL-liposome of PC/DPPC/CH0L/TA displayed the most significant sustained release. The addition of DPPC appeared to be favorable for the control of release. In general, aclarubicin entrapped in liposomes was less stable than free aclarubicin either in pH 7.4 phosphate buffer or in human plasma. Formulation I($t_{1/2}$, 20.3 hr) devoid of lipid additive was the most unstable in the phosphate-buffer solution while formulation II($t_{1/2}$, 40.7 hr) with cardiolipin was the most stable. Half lives of aclarubicin-entrapped liposomes in human plasma were 43.2, 50.7, 35.9 and 35.3 hr for formulation I. II, III and IV, respectively, in contrast to 57.8 hr for free aclarubicin.

• Health Policy and Management
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• v.23 no.1
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• pp.52-58
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• 2013

This study was conducted to investigate the responsiveness and its related factors of public health center for novel influenza A (H1N1) epidemic. The data was collected through a web-based survey conducted during February to April 2011. The 182 respondents were team leaders or persons who were responsible for H1N1-related work at public health centers during the H1N1 prevalence. The related factors affecting the responsiveness were different by urban or rural area. In the level of gu (urban) area, cooperation with the public organizations, preparing its own response plan were the significant factors. But, in the level of si or gun (rural) area, cooperation with private organizations (clinic or pharmacy), physical (facilities, equipments, and medicines), and human infrastructures (public health professions, education and knowledge, and motivation) were more important factors. Therefore, how to cope with H1N1 prevalence in the future should be different by local characteristics. As a result, there are several challenges that public health centers should prepare for the further emerging infectious diseases. First, it is needed to make standard manuals which could strengthen education and training in order to respond appropriately, as well as to prepare enough physical infrastructures for the crisis. Next, the public health center should prepare correct media response and cooperation system with public and private organizations.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.479-489
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• 2015

The paradigm of communication is changing by the generalization of mobile computers and the extension of network service. In the mobile messenger communication, people are increasingly using character emoticons to substitute linear text. This means that the character emoticons are functioning as narrative characters so that they are becoming the nonlinear techno-code, which can substitute for the alphabet code. As Vil$\acute{e}$m Flusser said, the post-modern communication is arrived. In this kind of communication, storytelling with character emoticons are effective enough to tell various stories. In this point of view, this paper tries to prove the functions of character emoticons and suggests the classification of the character emoticon series. This paper also structures the post-modern communication model as a new paradigm of visual communication.