• Polymer(Korea)
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• v.25 no.5
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• pp.649-656
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• 2001

Miscibility of poly(4-vinylpyridine) (P4VP) blends with poly(vinyl acetate-co-vinyl alcohol) (VAc-VAL copolymers) was investigated as a function of comonomer composition of VAc-VAL copolymers. Differential scanning calorimetry (DSC) and thermo-optical microscopic (TOM) analysis confirmed that P4VP is miscible with VAc-VAL copolymers containing more than 30 mole% VAL. Fourier transform inflated (FT-IR) spectroscopic analysis revealed that the strong intermolecular hydrongen bonding interaction between the vinylpyridine and VAL hydroxyl group was formed. Theoretical phase diagram was constructed by the calculation using the Association model, a thermodynamic model for hydrogen-bonded polymer blend systems developed by Coleman et al. The calculated theoretical binodal phase diagrams were in good agreement with the experimentally determined cloud point curves.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.52-55
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• 2009

With the recent development of virtual reality, it has been actively investigated to develop user interfaces for immersive interaction. Immersive user interfaces improve the efficiency and the capability of information processing in the virtual environment providing various services, and provide effective interaction in the field of ubiquitous and mobile computing. In this paper, we propose an virtual reality platform "My Workspace" which renders an 3D virtual workspace by using an immersive user interface. We develop an interface that integrates an optical see-through head-mounted display, a Wii remote controller, and a helmet with infrared LEDs. It estimates the user's gaze direction in terms of horizontal and vertical angles based on the model of head movements. My Workspace expands the current 2D workspace based on monitors into the layered 3D workspace, and renders a part of 3D virtual workspace corresponding to the gaze direction. The user can arrange various tasks on the virtual workspace and switch each task by moving his head. In this paper, we will also verify the performance of the immersive user interface as well as its usefulness with the usability test.

• Solar Energy
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• v.13 no.2_3
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• pp.79-90
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• 1993

A theoretical study is conducted for the design of solar air heaters using porous material. Radiative characteristics of glazing and porous absorbing media are found through spectral transmittances measured by the Visible spectrometer and the FT-IR. Using those characteristics the efficiencies of collectors are calculated one-dimensionally with the use of the Two-Flux radiation model. The efficiencies increase, as the air flow rates or albedos in the visible range increase, and as albedos in the IR range decrease. The optimum thickness of the porous medium of 15-mesh stainless steel wire screens is 0.001m, which represents the opacity of one.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.340-341
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• 2013

양자점(Quantum dots; QDs)은 단전자 트랜지스터, 레이저, 발광다이오드, 적외선 검출기와 같은 고효율 광전소자 응용을 위해 활발한 연구가 진행되고 있다. II-VI 족 화합물 반도체는 III-V 족 화합물 반도체와 비교했을 때 더 큰 엑시톤 결합에너지(exciton binding energy)를 가지는 우수한 특성을 보이고 있으며 이러한 성질을 가지는 II-VI 족 화합물 반도체 중에서도 넓은 에너지 갭을 가지는 CdTe 양자점은 녹색 영역대의 광전자 소자로서 활용되고 있다. 기존의 CdTe/ZnTe 양자점을 성장하기 위해 ZnTe와 격자부정합이 적은 GaAs 기판을 이용한 연구가 주를 이룬 반면 Si기판을 이용한 연구는 미흡하다. 하지만 Si 기판은 GaAs 기판에 비해 값이 싸고, 여러 분야에 응용이 가능하며 대량생산이 가능하다는 이점을 가지고 있어 초고속, 초고효율 반도체 광전소자의 제작을 가능케 할 것으로 기대된다. 또한 양자점의 고효율 광전소자에 응용을 위해서는 Si 기판 위에 양자점의 크기를 효율적으로 조절하는 연구 뿐 아니라 양자점의 크기에 따른 운반자 동역학에 대한 연구도 중요하다. 본 연구에선 분자선 에피 성장법(Molecular Beam Epitaxy; MBE)과 원자층 교대 성장법(Atomic Layer Epitaxy; ALE)을 이용하여 Si 기판 위에 성장한 CdTe/ZnTe 양자점의 크기에 따른 광학적 특성을 연구하였다. 저온 광 루미네센스(PhotoLuminescence; PL) 측정 결과 양자점의 크기가 증가함에 따라 더 낮은 에너지영역으로 피크가 이동하는 것을 확인하였다. 그리고 온도 의존 광루미네센스 측정 결과 양자점의 크기가 증가함에 따라 열적 활성화 에너지가 증가하는 것을 관찰하였는데, 이는 양자점의 운반자 구속효과가 증가하였기 때문이다. 또한 시분해 광루미네센스 측정 결과 CdTe/ZnTe 양자점의 크기가 증가함에 따라 소멸 시간이 긴 값을 갖는 것을 관찰하였는데, 이는 양자점의 크기가 증가함에 따라 엑시톤 진동 세기가 감소하였기 때문이다. 이와 같은 결과 Si 기판 위에 성장한 CdTe/ZnTe 양자점의 크기에 따른 열적 활성화 에너지와 운반자 동역학에 대해 이해 할 수 있었다.

• Economic and Environmental Geology
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• v.17 no.4
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• pp.273-282
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• 1984

The Buncheon manganese ore deposits occur in vein along the fault of $N20^{\circ}E$, cutting the foliation of Yulri Series. The deposits consist of primary manganese silicate ores in the deeper part and superficial manganese oxide ores near the surface. The spatial distribution of manganese oxide ores with respect to the manganese silicate ores suggests that the manganese oxide ores are the supergene oxidation product of the manganese silicate ores. Manganese silicate ores consist mainly of fine-to coarse-grained pyroxmangite with minor rhodochrosite, quartz, sulfides and chlorite. Manganese oxide ores are composed of supergene manganese oxides such as nsutite, birnessite, manganite and todorokite, and other associated minerals. Paragenetic sequence of formation of the manganese minerals are as follows: $\array{{rhodochrosite{_{\rightarrow}^o}todorokite{_{\searro}^o}}\\pyroxmangite{_{\line(10){90}}^o}{\nearro}}birnessite{_{\rightarrow}^o}nsutite{_{\rightarrow}^s}manganite$ In order to elucidate the mineralogy of the manganese minerals, microscopic, X-ray, IR spectroscopic, and thermal studies were made for manganese and associated minerals.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.37-42
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• 2008

Purpose: This study is to prepare tintable hard coatings for plastic lenses and to evaluate spectroscopic and surface characteristic for these coatings. Methods: These coatings had been prepared by the sol-gel method using TEOS, MTMS and GPTS. Scanning electron microscopy (SEM), Raman spectroscopy, infrared (IR) spectroscopy and UV/VIS spectroscopy have been used to investigate the optical and structural characteristics of the coatings. Results: Tint ability of this coating was about 2 times higher than general hard coatings. The lenses applied by tintable hard coatings showed excellent adhesion, abrasion resistance, hot water resistance, and chemical resistance. Pencil hardness was 5H and the surface of coatings was smooth and free of cracks. Conclusions: This hard coating system for plastic lenses offered a hard and stable surface that could be tinted.

• Journal of the Korean Vacuum Society
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• v.21 no.1
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• pp.22-28
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• 2012

Transparent dye-sensitized solar cells have been widely investigated for the application to building integrated photovoltaic system. Thin film Si-based solar cells are emerging as a substitute for the dye-sensitized solar cells because their merits of well-established manufacturing processes. Since the selective transmitting layer transmits visible light and reflects infrared light, the solar cell efficiency increases with the introduction of the selective transmitting layer. In this work, AlTiO thin films were grown as the selective transmitting layer by cost-effective sputter deposition and their transmittances were improved by controlling deposition parameters.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.229-234
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• 2013

The purpose of this study is to develop a lighting apparatus of the illuminance and color temperature to maximize the ability of the optimal combination of light sources that can be controlled efficiently control device. Finding people comfortable feeling for indoor lighting that can be used in a variety of color temperature illumination area by combining light sensitivity can be realized. Lighting apparatus for fluorescent lamps with different color temperature of 2000K and 8000K, and by varying the quantity of each of the fluorescent lamps, the illuminance of lighting equipment and color temperature through optical simulations were evaluated. By infrared remote control receiver, divided into 5 types of relaxation, conversation, meeting, hospitality, arts and the lighting environment you want to transfer the PC0 ~ PC4 through the parallel port on the mode selected by the user at the receiving end the DC voltage output. EEFL inverter input DC voltage and the DC input voltage, depending on the level of EEFL dimming value (illuminance and color temperature) lighting environment you want to create change while using a PIR sensor EEFL automatically turn off if people do not have was developed so that the power consumption so you can save.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.8
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• pp.1747-1752
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• 2012

The SiOC film of carbon centered system was prepared using bistrimethylsilylmethane (BTMSM) and oxygen mixed precursor by the chemical vapor deposition. The dielectric constant is measured by MIS(metal/insulator/Si) structure, but it could decrease the reliability because the uniformity is not assured. To research the dielectric constant of SiOC film, the range of low polarization was researched in SiOC film using the optical analysis and hardness, and then calculated the dielectric constant of SiOC film with amorphous structure of high degree. After annealing, the dielectric constant of SiOC film was decreased owing to the lowering of polarization, and FTIR spectra of the main bond was shifted to higher wave number. The main bond of 950~1200 cm-1 was composed of the Si-C and Si-O bonds. The intensity increases in Si-O bond infers the bonding strength became stronger than that of deposited film. Annealed SiOC film showed 2.06 in dielectric constant.

• 전자공학회논문지 IE
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• v.45 no.3
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• pp.27-35
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• 2008

In this paper, we propose a minute signal detection algorithm for a development of optical analyzer, using the non-dispersive infrared method with multi gas filter correlation wheel, that can measure various environmental air-pollution materials (CO, SO2, NOx, etc.) in real-time. The MCT(mercury cadmium telluride) sensor can detect minute signals those show and absorption characteristic of each environmental pollution materials. In the proposed method, a corresponding data of each environmental pollution materials can be separated by an external trigger and threshold values in the measured continuous signals.