• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.587-587
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• 2013

ZnS is well-known direct band gap II-VI semiconductor, and it attracts intense interest due to its excellent properties of luminescence which enable ZnS to have promising materials for optical, photonic and electronic devices. Especially, the emission wavelength of ZnS falls in the UV absorption band of most organic compoundsand biomolecules, thus it is envisaged that ZnS based devices may find applications in increasingly important fluorescence sensing. We have developed a facile and effective one-step process for the fabrication of single-crystalline and pure-wurtzite ZnS nanostructures possessing sharp band-edge emission at room-temperature having diverse length-to-width ratios. Each of nanostructures was composed of chemically pure, structurally uniform, single-crystalline, and defect-free ZnS. These features not only suppress trap or surface states emission centered at 420 nm, but also enhance UV band-edge emission centered at 327 nm, which give as-synthesized our ZnS nanostructures possible sharp UV emission at room temperature. The reaction medium consisting of mixed solvents such as hydrazine, ethylenediamine, and water as well as proper reaction time and temperature have played an important role in the crystallinity and optical properties of ZnS nanostructures. As-synthesized our ZnS nanostructures possessing sharp UV emission guarantee high potential for both fundamental research and technological applications.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2333-2337
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• 2012

We report the synthesis and thermal annealing of Si-core/ZnO-shell nanorods using a two-step process comprising the metal-assisted electroless etching of Si and the sputter deposition of ZnO. Transmission electron microscopy and X-ray diffraction analysis showed that the cores of the annealed core-shell nanorods were single crystal diamond cubic-type Si, whereas the shells of the annealed core-shell nanorods were single crystal wurtzite-type ZnO. The PL spectra of Si nanorods consisted of a broad red emission band and a weaker blue emission band. The major emission band of Si nanorods was shifted from 700 nm (in the red region) to 440 nm (in the violet region) by ZnO coating. The violet emission of the core-shell nanorods was enhanced in intensity considerably by annealing in an oxidizing atmosphere. The origin of the PL enhancement by annealing is also discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.16-17
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• 2006

In this paper, Ni-V alloy was studied with different structures and thickness. In case of Ni-V and Ni-V/Co/TiN, low resistive Ni silicide was formed after one step RTP (Rapid Thermal Process) with temperature range from $400^{\circ}C$ to $600^{\circ}C$ for 30sec in vacuum. After furnace annealing with temperatures range from $550^{\circ}C$ to $650^{\circ}C$ for 30min in nitrogen ambient, Ni-V single structure shows the best thermal stability compare with the other ones. To enhance the thermal stability up to 650oC and find the optimal thickness of Ni silicide, different thickness of Ni-V was studied in this work. Stable sheet resistance was obtained through Ni-V single structure with optimal Ni-V thickness.

• BMB Reports
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• 제54권3호
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• pp.157-163
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• 2021

The transient interactions between cellular components, particularly on membrane surfaces, are critical in the proper function of many biochemical reactions. For example, many signaling pathways involve dimerization, oligomerization, or other types of clustering of signaling proteins as a key step in the signaling cascade. However, it is often experimentally challenging to directly observe and characterize the molecular mechanisms such interactions-the greatest difficulty lies in the fact that living cells have an unknown number of background processes that may or may not participate in the molecular process of interest, and as a consequence, it is usually impossible to definitively correlate an observation to a well-defined cellular mechanism. One of the experimental methods that can quantitatively capture these interactions is through membrane reconstitution, whereby a lipid bilayer is fabricated to mimic the membrane environment, and the biological components of interest are systematically introduced, without unknown background processes. This configuration allows the extensive use of fluorescence techniques, particularly fluorescence fluctuation spectroscopy and single-molecule fluorescence microscopy. In this review, we describe how the equilibrium diffusion of two proteins, K-Ras4B and the PH domain of Bruton's tyrosine kinase (Btk), on fluid lipid membranes can be used to determine the kinetics of homodimerization reactions.

• Current Optics and Photonics
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• 제7권5호
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• pp.529-536
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• 2023

The Morlet wavelet transform method is proposed to analyze a single interferogram with spatial carrier frequency that is captured by an optical interferometer. The method can retain low frequency components that contain the phase information of a measured optical surface, and remove high frequency disturbances by wavelet decomposition and reconstruction. The key to retrieving the phases from the low-frequency wavelet components is to extract wavelet ridges by calculating the maximum value of the wavelet transform amplitude. Afterwards, the wrapped phases can be accurately solved by multiple iterative calculations on wavelet ridges. Finally, we can reconstruct the wave-front of the measured optical element by applying two-dimensional discrete cosine transform to those wrapped phases. Morlet wavelet transform does not need to remove the spatial carrier frequency components manually in the processing of interferogram analysis, but the step is necessary in the Fourier transform algorithm. So, the Morlet wavelet simplifies the process of the analysis of interference fringe patterns compared to Fourier transform. Consequently, wavelet transform is more suitable for automated programming analysis of interference fringes and avoiding the introduction of additional errors compared with Fourier transform.

• 한국구조물진단유지관리공학회 논문집
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• 제27권6호
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• pp.86-93
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• 2023

반복하중을 받는 철근콘크리트 부재는 이력거동이 진행됨에 따라 강성과 강도의 저하 그리고 핀칭현상 등으로 인하여 에너지소산 능력이 감소된다. 그러나 지침서 「철근콘크리트 건축구조물의 성능기반 내진설계를 위한 비선형해석모델, 2021」에서는 각 부재별로 모든 이력단계별 단일한 에너지소산계수를 산정하도록 하고 있어 이력단계에 따른 에너지소산능력의 감소를 고려할 수 없을 것으로 판단된다. 따라서 본 연구에서는 반복하중을 받는 일반보에 대한 기존 실험결과와 비선형시간이력해석 결과를 비교하여 이력단계에 따른 에너지소산계수를 고찰하였다. 에너지소산계수는 비선형시간이력해석 결과로 구한 이상화된 탄소성거동 에너지 소산량에 대한 실제 실험체의 에너지소산량의 비로써 산출하였다. 기존 실험결과는 1회 Cycle을 각 이력단계별로 산정하여 에너지소산계수를 도출하였으며, 지침서 내 비선형모델링 과정을 토대로 에너지소산계수를 도출하였다. 기존 실험연구에선 각 이력단계(Y-L-R)를 설정하여 에너지소산계수를 구하였으며, 에너지소산계수는 Y-L구간 0.36, L-R구간 0.28로 나타났고, 지침서 에너지소산계수는 0.31로 나타났다. 이는 지침서의 에너지소산계수 산정식이 철근콘크리트 부재의 에너지소산능력의 감소를 나타내지 못하는 것으로 나타났다.

• 사회복지연구
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• 제41권1호
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• pp.5-37
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• 2010

본 연구는 장기간의 활동을 통해 다양한 변화 과정을 경험해온 빈곤 한부모여성 자조집단을 대상으로, 정체기 이후 자조집단 참여자들이 변화를 주도하게 된 동기와 과정 및 전략을 살펴보고 그 변화가 참여자들과 소속집단, 기관에 주는 시사점을 분석함으로써 자조집단이 지향해야 할 실천방향을 모색하는데 목적이 있다. 이를 위해 참여자와 실천가가 협력적으로 대안을 모색하는 참여실행 연구방법(PAR)을 적용하여, 문제도출, 지역조사 및 계획, 실행, 평가 및 검토의 4단계에 걸친 연구과정을 통해 변화의 과정과 내용을 분석하고 그에 따른 사회복지실천의 함의를 고찰하였다. 연구결과, 첫째, 자조집단 참여자들의 변화 동기는 주체적으로 활동방향을 결정해야 한다는 문제인식에서 비롯되었으며, 그 결과 자신들의 역량을 고려한 활동모색을 변화의 필요성으로 도출하였다. 둘째, 변화를 모색하는 과정에서 참여자들은 변화의 범위와 내용을 주도적으로 결정했으며, 그 결과 정서적 지지를 넘어서 '목적성 있는 활동'을 지향하고자 하였다. 셋째, 변화를 위한 구체적인 전략으로 '의미있는 활동'이 제시되었으며 이는 지역자원봉사활동과 한부모 참여자 강사활동으로 계획·실행되었다. 결론적으로 자조집단이 지향해야 할 변화는, 참여자들의 주체적 인식의 변화를 기반으로 실천가 중심에서 참여자 중심의 실천으로 실천주체가 변화해야 할 것으로 나타났으며, 이를 통해 자신의 삶을 조성하는 사회적 조건에 대한 통제력을 갖도록 사회적 차원의 임파워먼트를 강화하는 것으로 나타났다. 나아가 자조집단의 한계를 극복하기 위해 공동체적 접근으로의 변화를 고려해보아야 할 필요성이 있는 것으로 제시되었다. 이러한 분석결과를 바탕으로 본 연구가 사회복지실천에 주는 함의를 제시하였다.

• 한국산학기술학회논문지
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• 제12권2호
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• pp.847-851
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• 2011

태양광 발전 시스템은 친환경성을 바탕으로 설치용량이 증가하고 있으며 효율 개선을 위한 연구가 활발하다. 고 효율 시스템 설계를 위해서는 태양전지 패널의 출력특성을 정확히 파악하는 것이 중요하다. 태양전지 패널은 단일 다이오드 모델로 물리적 특성을 표현할 수 있으나, 정확한 파라미터를 얻는 것은 여러 단계의 측정과 수치해석 등의 복잡한 과정을 거쳐야 한다. 본 논문에서는 패널 제조사의 데이터 시트에 제공되는 태양전지 패널의 I-V 특성곡선을 기반으로 패널의 단일 다이오드 모델의 특성 파라미터를 추출하는 방법을 제시하였다. 제시한 방법의 검증을 위하여, Simulink의 Solar Cell 블록에 추출한 파라미터를 입력하여 출력을 측정하고, 데이터 시트와 오차를 계산하였다.

• Geomechanics and Engineering
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• 제19권2호
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• pp.105-114
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• 2019

In this paper, simulation tests were conducted with similar materials to study the distribution of residual voids in longwall goaf. Short-time step loading was used to simulate the obvious deformation period in the later stage of arch breeding. Long-time constant loading was used to simulate the rheological stage of the arch forming. The results show that the irregular caving zone is the key area of old goaf for the subsidence control. The evolution process of the stress arch and fracture arch in stope can be divided into two stages: arch breeding stage and arch forming stage. In the arch breeding stage, broken rocks are initially caved and accumulated in the goaf, followed by the step deformation. Arch forming stage is the rheological deformation period of broken rocks. In addition, under the certain loads, the broken rock mass undergoes single sliding deformation and composite crushing deformation. The void of broken rock mass decreases gradually in short-time step loading stage. Under the water lubrication, a secondary sliding deformation occurs, leading to the acceleration of the broken rock mass deformation. Based on above research, the concept of equivalent height of residual voids was proposed, and whose calculation equations were developed. Finally, the conceptual model was verified by the field measurement data.

• 한국실내디자인학회논문집
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• 제8호
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• pp.44-57
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• 1996

Now interior designers have to meet this challenge by rising to the occasion and taking advantage of opportunities while strengthening their skills which have not kept pace with the increasing emphasis on design. furthermore, they are hampered by the lack of a general working design methodology. Interior designers in Korea have been slow to recognize the need for developing a specification methodology manual which could be adapted to meet varying requirements and modified to reflect designers experiences. The design process in Korean interior design often involves utilizing drawing document methods based on architectural prototypes rather than upon drawing methods developed by design firms as a result of work experience s and unique needs. However, these unique nees are nearly always limited by traditional working drawing methods. This has led to confusion and inaccuracies due to the lack of a single starndardized and universally acceptable working drawing methodology which is capable of reflecting the needs of all parties involved , partiality those of interior designers. This thesis is an attmepted to establish the necessity for developing a better working drawing methodogoy or technical mans of satisfying the information sorting and processing need s of interior design professionals, a five step suggestion for developing such a methodology follows. First, arrange pertinent design research information by means of a process which can be employed throughout the design process, from inception through to working drawing stage. The end result should be an interior architectural design process culminating in a pattern skillfully blending architecture, vision and product with environment . The design process should be manifested into a series of definable steps and yet sufficiently flexible and variable in order to provide the most apropos design solution. Secondly , motify the design methodology systematically according to site conditions and prevailing construction technology and manifest the design process in a booklet form so that it reflects a desired pattern. Thirdly, this methodology should incorporate a stand-ardized and functional process capable of being utilized to impact clear design concepts and objectives with preci-sion and efficiency in a manual form.