• 한국세라믹학회지
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• 제47권5호
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• pp.450-456
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• 2010

During the process of synthesizing green celsian pigments, attempts were made to replace a given amount of $BaCO_3$ with $SrCO_3$ to accelerate the hexagonal to monoclinic celsian phase transition, which was assumed to promote color development. Monoclinic celsian have been synthesized from Hongkong-Kaolin, $BaCO_3$, $SrCO_3$, $Al(OH)_3$, $SiO_2$ and $SrCO_3$ with 1 to 1.5 wt% of LiF as a mineralizer from 1100 to $1300^{\circ}C$. It was found that replacing $BaCO_3$ with $SrCO_3$ allowed monoclinic celsian to be formed at a lower temperature. While the pigments containing 1 mole of $BaCO_3$ were difficult to synthesize monoclinic celsian with absence of the mineralizer, the formation of monoclinic celsian was successfully achieved even without mineralizer by using 0.25 mole of $SrCO_3$ at $1250^{\circ}C$ for 1 h. The color development was improved from yellowish green to green with increasing amount of $SrCO_3$ being replaced.

• Corrosion Science and Technology
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• 제8권1호
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• pp.27-39
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• 2009

Non metallic composite materials, for example, GECM(graphite epoxy composite material) show high specific strength because of low density. These kinds of non metallic composite materials improved the structural effectiveness and operation economics. However, if these materials contacted several metals, corrosion can be arisen since non metallic composite materials have electrical conductivity. This paper dealt with galvanic corrosion between graphite epoxy composite material and several metals. Base on the electrochemical galvanic corrosion test between GECM and metals, corrosion current of carbon steel and aluminium increased with time but corrosion current of stainless steels and titanium decreased and galvanic potential increased. This behavior shows the galvanic corrosion depends upon the presence of passive film. Also, galvanic effect of GECM coupled with ferrous alloys and non-ferrous alloys was lower than that of 100% graphite, which is attributed to lower exposed area of graphite fiber in the GECM than apparent area of the GECM specimen used for the calculation of galvanic current in this work.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.282-283
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• 2009

In the research, we have proposed a novel encapsulation with simple process and steady film for external environment in comparison with conventional encapsulation method. This was designed to cover the emitting organic material from air. Silicon 야oxide was used for thin film of encapsulation and the deposition thickness of the organic film was 220 nm. Operating voltage of green OLED with encapsulation was 5.5 V and luminance was 7.370 cd/$m^2$ at the applied voltage of 14.5 V. Luminance was measured in 10 hour intervals at the air-exposed condition. After 110 hours and 300 hours, luminances of green OLED were 7,368 and 7,367 cd/$m^2$, respectively. Luminance of green JLED doesn't decrease until 300 hours. As a results, proposed encapsulation can increase the life time of green OLED.

• 한국전기전자재료학회논문지
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• 제23권6호
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• pp.458-463
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• 2010

MLCC (multi-layer ceramic capacitor) is usually fabricated by lamination of predetermined number of single layers. Often, the state of MLCC before sintering is called the green state, whose strength comes from the adhesion between the dielectric material and the polymer binder. Therefore the lamination of a single layer before sintering can be easily deformed by environment due to the relatively lower strength. After the compression process, which helps single sheets cohereto with adjacent sheets, the MLCC green bar is preheated to resolve the probable internal stress. Unfortunately, unexpected deformation after preheating resulted in problems during cutting of the MLCC green bar. In this study, one of 2 primary hypotheses which were proposed to resolve the unexpected deformation after preheating was examined by quantitative experiment with GC/MS (gas chromatograpy/mass spectrometer). The proportion of deformation caused by DOP evaporation, which was primarily evaporated componet during preheating, to the total deformation of the MLCC green bar was found to be 53%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.233-233
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• 2010

It is important to form the n+ emitter layer for generating electric potential collecting EHP(Electron-Hole Pair). In this paper the formation on the n+ emitter layer of silicon wafer has been made with respect to uniformity of shallow diffusion from a liquid source. The starting material was crystalline silicon wafers of resistivity $0.5{\sim}3\{Omega}{\cdot}cm$, p-type, thickness $200{\mu}m$, direction[100]. The formation of n+ emitter layer from the liquid $POCl_3$ source was carried out for $890^{\circ}C$ in an ambient of $N_2:O_2$::10:1 by volume. And than each conditions are pre-deposition and drive-in time. It has been made uniformity of at least. so, the average of sheet resistance was about 0.12%. In this study, sheet resistance was measured by 4-point prove.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.32-35
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• 2006

For the white UV-LED applications, $Eu^{2+}$-activated calcium aluminium silicate phosphors were synthesized for the first time and the structures and luminescence characteristics of these phosphors were investigated. The phosphors in this study emitted blue. green or blue-green light depending on the starting materials for synthesis. In addition, the structure was also changed when the different starting materials were used. When CaO and $CaCO_3$ was used as a starting material. tetragonal $Ca_2Al_2SiO_7$ was formed and blue-green and pure green light was emitted. respectively. However. in the case of $CaSiO_3$, triclinic $CaAl_2Si2O_8$ was formed and only pure blue emission was detected. The maximum emission intensity was obtained from $CaAl_2Si_2O_8:Eu^{2+}$ phosphors, which intensity was about 1.4 times higher than that of YAG:$Ce^{3+}$ phosphor used for blue LED.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제16권1호
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• pp.43-53
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• 2010

This study purports to investigate the status quo of the environmentally-friendly green healthcare in teaching hospitals through the questionnaire survey. Data were collected from a total of 46 hospitals. The survey results revealed that most teaching hospitals did not meet the global standard of environmentally-friendly green hospitals. Especially, such items as alternative energy system, water recycling, CO2 emission reduction, green building construction, installation of pond or spring were found to be significantly below global standard. Based upon the study results, various strategies for establishing green hospitals were discussed. For example, energy saving design, such as solar heating, natural wind cooling, automatic temperature controller, green material use, wall surrounded by ivy, were recommended. In conclusion, the strategy and evaluation tool developed in the study will provide a good guide for establishing environmentally-friendly green hospitals.

• 한국전기전자재료학회논문지
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• 제27권3호
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• pp.189-194
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• 2014

In this paper, PV modules using a low-temperature conductive film(LT-CF) as a bonding material between a cell and a solder free ribbon were produced and chracterized, which is more environmental-friendly, cost effective and high efficient. Mainly, filed electrical performance of PV modules using three different types of bonding material; a convetional solder ribbon(SR), a LT-CF and a light-capturing Ribbon(LCR) were compared to comfirm the feasibility of LT-CF as a bonding material. The filed test were conducted for 3 months and results were discussed in terms of amount of output energy production and efficiency.

• Journal of Magnetics
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• 제12권2호
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• pp.72-76
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• 2007

We investigate the spin transfer torque in metallic multilayer system by employing Keldysh non-equilibrium Green function method. We study the dependences of the spin transfer torque on the detailed energy configuration of ferromagnetic, spacer, and lead layers. With Keldysh non-equilibrium Green function method applied to a single band model, we explore spin transfer torque effect in various layer structures and for various material parameters.

• Nutrition Research and Practice
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• 제10권1호
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• pp.108-114
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• 2016

BACKGROUND/OBJECTIVES: Sustainable practices in foodservice organizations including commercial and noncommercial ones are critical to ensure the protection of the environment for the future. With the rapid growth of the foodservice industry, wiser usage of input sources such as food, utilities, and single use packaging should be reconsidered for future generations. Therefore, this study aims to investigate the customer's perceptions on sustainable practices and to identify the relationship among sustainable practices, social contribution and purchase intention. SUBJECTS/METHODS: The study was conducted using content analyses by reviewing articles on sustainable food service practices published domestically and abroad. Thereafter, data were collected with a face-to-face survey using a questionnaire and analyzed with factor analyses and multiple regressions. RESULTS: Sustainable practices classified with factor analysis consisted of 6 dimensions of green food material procurement, sustainable food preparation, green packaging, preservation of energy, waste management, and public relations on green activity, with a total of 25 green activities in foodservice operations. Consumers were not very familiar with the green activities implemented in the foodservice unit, with the lowest awareness of "green food material procurement (2.46 out of 5 points)", and the highest awareness of "green packaging (3.74)" and "waste management (3.28). The factors influencing the perception of social contribution by foodservice organizations among 6 sustainable practice dimensions were found to be public relations on green activity (${\beta}=0.154$), waste management (${\beta}=0.204$) and sustainable food preparation (${\beta}=0.183$). Green packaging (${\beta}=0.107$) and the social contribution of the foodservice organization (${\beta}=0.761$) had strong relationships with the image of the organization. The purchase intentions of customers was affected only by the foodservice image (${\beta}=0.775$). CONCLUSIONS: The results of this study suggest that sustainable practices by foodservice organization present a good image to customers and increase the awareness of valuable contributions that benefit the customer as well as the community.