• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.439-439
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• 2012

태양광 발전은 발전 셀의 특성상 태양광의 일사량, 태양과 셀 단면이 이루는 각도에 따라서 발전량의 차이를 가져온다. 실리콘 태양전지의 전면 texturing은 입사광의 반사율을 크게 감소시키고, 태양전지 내에서 빛의 통과길이를 증가시켜 태양전지 내의 흡수하는 빛의 양을 증가 시키는 역할을 한다. 따라서 전면 texturing은 단락전류를 증대시키는 효과를 가지고 온다. 일반적으로 texturing은 alkaline etching (WET) 공정과 reactive ion etching (RIE) 공정이 사용된다. 그리고 다결정 실리콘 태양전지의 경우에는 재료의 결정방향에 따라 식각이 되어지는 WET 공정의 경우 texturing 모양을 제어할 수 없어 효과적이지 못하는 결과를 가지고 온다. 본 연구에서는 Electroluminescence을 측정하여 RIE, WET 공정을 사용하여 만든 texturing 구조의 다결정 태양전지의 Microcrack 및 Defect, Electrode Failure, Hot spot등을 검출하였으며, ${\mu}$-PCD 측정 결과와 비교 분석하여 Micro carrier life time을 유추하여 계산하였다. 또한 반사율을 측정해본 결과 WET 공정 대비 RIE의 경우 단파장영역에서 반사율이 크게 감소하여, 상대적으로 높은 External quantum efficiency (EQE)가 측정되었다. 이는 Jsc를 증가시켜, 태양전지의 효율이 증가되는 결과를 얻을 수 있었다.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.11-21
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• 2012

Hybrid network infrastructure has been deployed as the most important technology for the advanced research networking community such as Internet2, SURFnet, etc. However, further research needs to be performed in terms of feasible design and implementation of architecture for inter-domain collaborative network infrastructure, which is essential to end-to-end collaborative research based on high-end applications. In this paper, we suggest a framework for distributed and virtual network operations based on hybrid research networks and efficient cooperation between multi-domain hybrid networks, which aims to provide collaborative network environment for high-end applications. Suggested framework is designed to adopt decentralized model of multi-domain hybrid research network management. A collaborative and distributed virtual model that is characterized by cooperation among hybrid research networks that insist on maintaining their autonomy and control, can also contribute for researchers and other end-users to manage and operate their own virtual networks.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.124-129
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• 2006

음악은 소리를 즐긴다는 뜻을 담고 있다. 감상자에게 단순한 청각적 자극을 넘어 즐거움을 주기 위해선 음악적인 경험이 뒷받침되어야 한다. 가상 현실을 이용한 사용자와 시스템 간의 상호작용을 음악 경험 제공에 접목하려는 시도는, 새로운 경험을 통해 일반인들이 보다 쉽게 음악을 접하고 체험함으로써 음악을 통해 즐거움을 얻을 수 있도록 도움을 주는 데에 그 목적이 있다. 가상 오케스트라를 구현하고 지휘 동작을 재현하는 것은 이러한 가능성을 극대화하는 연구이다. 본 논문에서는 가상 오케스트라를 구현하기 위해 필수적인 중간 단계로, 사용자의 지휘 동작을 감지하여 연주의 박자(속도)를 제어하는 지휘 시뮬레이션 시스템을 제시한다. 실제의 지휘 동작을 분석하고, 동작의 변화를 인식하기 위하여 가속도 센서를 이용, 공간상에서 지휘봉의 움직임을 가속도 정보로 수집하여 이에 상응하는 박자의 제어를 구현한다. 사용자의 박자 명시에 따라 변화하는 상하 방향의 가속도를 센서를 통해 전압 신호로 입력 받고, DSP 의 A/D conversion 모듈에서 디지털 신호로 변환, 일정 수준 이상의 신호를 박자 정보로 직렬통신을 통해 컴퓨터에 전달한다. 컴퓨터에서는 Max/MSP를 이용하여 각 박자 사이의 시간 간격을 측정하고 상응하는 MIDI 음악을 재생하는 방식으로 시스템이 구현된다. 기존 연구에서 사용된 CCD 카메라에 의한 Motion Tracking 을 보완하여 동작의 크기에 따라 음량을 조절한다. 본 논문에서 제시되는 시스템은 지휘 동작에서 가장 특징적으로 나타나는 상하 방향의 급격한 가속도 변화를 직접 입력 받기 때문에 기존 시스템에 비해 지휘 동작의 인식 성공률을 높일 수 있으며, 화상 처리 및 계산에 의한 지연을 최소화할 수 있다. 또한, 장치의 규모를 소형화하여 보다 지휘봉의 형태에 가까운 인터페이스를 제공하며, 적합한 응용 콘텐츠를 접목할 경우 게임 컨트롤러로의 발전 가능성이 있다.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.357-357
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• 2012

The doping process of the solar cell has been used by furnace or laser. But these equipment are so expensive as well as those need high maintenance costs and production costs. The atmospheric pressure plasma doping process can enable to the cost reduction. Moreover the atmospheric pressure plasma can do the selective doping, this means is that the atmospheric pressure plasma regulates the junction depth and doping concentration. In this study, we analysis the atmospheric pressure plasma doping compared to the conventional furnace doping. the single crystal silicon wafer doped with dopant forms a P-N junction by using the atmospheric pressure plasma. We use a P type wafer and it is doped by controlling the plasma process time and concentration of dopant and plasma intensity. We measure the wafer's doping concentration and depth by using Secondary Ion Mass Spectrometry (SIMS), and we use the Hall measurement because of investigating the carrier concentration and sheet resistance. We also analysis the composed element of the surface structure by using X-ray photoelectron spectroscopy (XPS), and we confirm the structure of the doped section by using Scanning electron microscope (SEM), we also generally grasp the carrier life time through using microwave detected photoconductive decay (u-PCD). As the result of experiment, we confirm that the electrical character of the atmospheric pressure plasma doping is similar with the electrical character of the conventional furnace doping.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.358-358
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• 2012

The application of BZO (Boron-doped Zinc Oxide) films use as the TCO(Transparent Conductive Oxide) material for display and solar cell industries, where the conductivity of the BZO films plays a critical role for improvement of cell performance. Thin BZO films are deposited on glass substrates by using RF sputter system. Then charging flow rates of O2 gas from zero to 10 sccm, thereby controlling the impurity concentration of BZO. BZO deposited on soda lime glass and RF power was 300 W, frequency was 13.56 MHz, and working pressure was $5.0{\times}10-6$ Torr. The Substrate and glass between distance 200 mm. We measured resistivity, conductivity, mobility by hall measurement system. Optical properties measured by photo voltaic device analysis system. We measured surface build according to oxygen flow rate from XPS (X-ray Photoelectron Spectroscopy) system. The profile of the energy distribution of the electrons emitted from BZO films by the Auger neutralization is measured and rescaled so that Auger self-convolution arises, revealing the detail structure of the valence band. It may be observed coefficient ${\gamma}$ of the secondary electron emission from BZO by using ${\gamma}$-FIB (Gamma-Focused Ion Beam) system. We observed the change in electrical conductivity by correlation of the valence band structure. Therefore one of the key issues in BZO films may be the valence band that detail structure dominates performance of solar cell devices. Demonstrating the secondary electron emission by the Auger neutralization of ions is useful for the determination of the characteristics of BZO films for solar cell and display developments.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1682-1688
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• 2005

Using the ASED-MO (Atom Superposition and Electron Delocalization-Molecular Orbital) theory, we investigated carbon formation and carbon hydrogenation for $CO_2$ methanation on the Ni (111) surface. For carbon formation mechanism, we calculated the following activation energies, 1.27 eV for $CO_2$ dissociation, 2.97 eV for the CO, 1.93 eV for 2CO dissociation, respectively. For carbon methanation mechanism, we also calculated the following activation energies, 0.72 eV for methylidyne, 0.52 eV for methylene and 0.50 eV for methane, respectively. We found that the calculated activation energy of CO dissociation is higher than that of 2CO dissociation on the clean surface and base on these results that the CO dissociation step are the ratedetermining of the process. The C-H bond lengths of $CH_4$ the intermediate complex are 1.21 $\AA$, 1.31 $\AA$ for the C${\cdot}{\cdot}{\cdot}H_{(1)}$, and 2.82 $\AA$ for the height, with angles of 105${^{\circ}}$ for ∠ $H_{(1)}$CH and 98${^{\circ}}$ for $H_{(1)} CH _{(1)}$.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.267-276
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• 2018

The purpose of this study was to identify the categories and frequencies of communication of students in nursing simulation using standard patient. Data were collected through questionnaires and video recording of communication process of 41 nursing students in simulation related to pediatric enteritis from March to June, 2017. The data were analyzed the contents and frequencies of completed communication forms by trained researcher based on Interaction Process Analysis. In result, students used communication skills in task area frequently. Communication skills, such as orientation, open question, identification, giving information, opinion, and suggestion, and eye contact, were used frequently. In an uncomfortable atmosphere such as listening to the nursing client's complaints, students showed tension and stiff appearance. Students used high quality communication skills such as empathic understanding and therapeutic touch restrictively. In conclusion, we need education strategies relating to therapeutic communication for nursing professionalism and qualitative improvement of nursing service.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.769-772
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• 2005

This paper describes a low-voltage and low-power channel selection analog front end with continuous-time low pass filters and highly linear programmable-gain amplifier(PGA). The filters were realized as balanced Gm-C biquadratic filters to achieve a low current consumption. High linearity and a constant wide bandwidth are achieved by using a new transconductance(Gm) cell. The PGA has a voltage gain varying from 0 to 65dB, while maintaining a constant bandwidth. A filter tuning circuit that requires an accurate time base but no external components is presented. With a 1-Vrms differential input and output, the filter achieves -85dB THD and a 78dB signal-to-noise ratio. Both the filter and PGA were implemented in a 0.18um 1P6M n-well CMOS process. They consume 3.2mW from a 1.8V power supply and occupy an area of $0.19mm^2$.

• Journal of Korean Clinical Health Science
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• v.5 no.3
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• pp.907-914
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• 2017

Purpose : This study was conducted to provide basic data on the relationship between environmental factors causing stress in clinical practice institutions and stress levels of dental hygiene students. Methods : The research subjects totaled 207 and it was analyzed with structured questionnaires. The collected data were analyzed using an IBM SPSS ver. 20.0. Results : The environmental factors causing stress according to the status of clinical practice institutions was statistically and significantly different in the case of Busan practice areas (p<0.01), dental university hospitals (p<0.001), attendance times prior to 8am (p<0.001), quitting times that surpassed 8pm (p<0.01), and the number of dentists exceeding 4 (p<0.01). It was found to affect the stress level of students when individuals had to stand for a long period of time(p<0.001, ${\beta}=0.254$) and with the use of unfamiliar tools and equipment(p<0.05, ${\beta}=0.178$). Conclusions : As a result of the research conducted, it should be concluded that dental clinics should provide rest areas for individuals to focus on clinical practice. In addition, it is necessary to develop a systematic program that enables students to communicate with students at any time during the training period.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.2
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• pp.1-10
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• 2018

Objectives : To present rough guide for the proper use of Lycii Fructus and Chrysanthemum indicum on ophthalmic patients. Methods : Traditional medical classics(本草綱目, 銀海精微, 秘傳眼科龍木論, 東醫寶鑑) and recent studies for Lycii Fructus and Chrysanthemum indicum were reviewed. Results : The results are as follows. 1. According to traditional medical classics, the efficacy of Lycii Fructus and Chrysanthemum indicum is removing nebula(退?) and improving acuity of vision(明目). 2. According to contemporary studies, Lycii Fructus has strong antioxidant, neuroprotective and anti-inflammatory effect. Chrysanthemum indicum has strong anti-inflammatory effect. Results and Conclusions : The Lycii Fructus is proper to macula or neuro-ophthalmology disease. Chrysanthemum indicum is proper to cornea or conjunctiva disease. Absolutely, It may be changed according to the individual condition. However, this may be a rough guide for usage in Korean medicine ophthalmology.