• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.378-381
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• 2008

고효율 a-Si:H/c-Si 이종접합 태양전지를 얻기 위해서는 우수한 c-Si wafer 위에 고품질의 비정질 실리콘박막을 통한 heterointerface를 형성하는 것이 매우 중요하다. 이를 달성하기 위해서는 공정중에 오염되기 쉬운 Si wafer 표면 상태를 정확히 검사하고 잘 관리하여야 한다. 본 연구에서는 세정 및 표면산화에 따른 Si wafer 상태를 Spectroscopic Ellipsometry 및 u-PCD를 이용하여 분석하였으며, <$\varepsilon$2> @4.25eV 값이 Si wafer 상태를 잘 나타내고 있음을 확인하였고 세정 최적화 할 경우 그 값이 43.02에 도달하였다. 또한 RF-PECVD로 증착된a-Si:H 박막을 EMA 모델링을 통해 분석한 결과 낮은 결정성과 높은 밀도를 가지는 a-Si:H를 얻을 수 있었으며, 이를 이종접합 태양전지에 적용한 결과 Flat wafer상에서 10.88%, textured wafer 적용하여 13.23%의 변환효율을 얻었다. 결론적으로 Spectroscopic Ellipsometry가 매우 얇고 고품질의 다층 박막이 필요한 이종접합 태양전지 분석에 있어 매우 유용한 방법임이 확인되었다.

• Smart Structures and Systems
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• v.29 no.5
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• pp.677-691
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• 2022

Water cycle algorithm (WCA) has been a very effective optimization technique for complex engineering problems. This study employs the WCA for simultaneous prediction of heating load (L_H) and cooling load (L_C) in residential buildings. This algorithm is responsible for optimally tuning a neural network (NN). Utilizing 614 records, the behavior of the L_H and L_C is explored and the captured knowledge is then used to predict for 154 unanalyzed building conditions. Since the WCA is a population-based algorithm, different numbers of the searching agents were tested to find the most optimum configuration. It was observed that the best solution is discovered by 500 agents. A comparison with five newly-developed benchmark optimizers, namely equilibrium optimizer (EO), multi-tracker optimization algorithm (MTOA), slime mould algorithm (SMA), multi-verse optimizer (MVO), and electromagnetic field optimization (EFO) revealed that the WCANN predicts the desired parameters with considerably larger accuracy. Obtained root mean square errors (1.4866, 2.1296, 2.8279, 2.5727, 2.5337, and 2.3029 for the L_H and 2.1767, 2.6459, 3.1821, 2.9732, 2.9616, and 2.6890 for the L_C) indicated that the most reliable prediction was presented by the proposed model. The EFONN, however, provided a more time-effective solution. Lastly, an explicit predictive formula was elicited from the WCANN.

• Polymer(Korea)
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• v.25 no.4
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• pp.568-574
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• 2001

PEO-like solid polymer electrolytes based on bisphenol A ethoxylate acrylate were synthesized and their electrochemical properties and mechanical stability were studied. Low molecular weight poly(ethylene glycol) dimethyl ether (PEGDMe) was added to increase the conductivity of the electrolyte. The maximum conductivity of the resulting polymer electrolyte was found to be 1.0 ${\times}$ 10$^{-3}$ S/cm [Bisphenol A ethoxylate diacrylate ([EO]/[phenol]= 15), PEGDMe250 80 wt%, LiCF$_3SO_3$] at 30$^{\circ}$C. Tensile strength of the free standing polymer electrolyte films was measured to be in the range of 0.4 ~ 5 MPa and these polymer electrolyte films did not show a crack even in 90$^{\circ}$ and 180$^{\circ}$ bending against ${\phi}$=3 mm bar. These electrolytes showed oxidation stability up to 4.5 V vs. lithium reference electrode.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.127-133
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• 2008

The foliar uptake of dimethomorph into cucumber was assessed by spray application of aqueous dimethomorph solution containing fatty alcohol ethoxylate (FAE) or fatty acid alkyl ester as activator adjuvants. Afterward, the possible mechanism of action of FAE on foliar penetration of active ingredient was suggested by speculating on the effect of lipophile and hydrophile of FAEs. The amount of absorbed dimethomorph induced by polyoxyethylene mono-9-octadecenyl ether (6 moles ethylene oxide, $C_{18=9}E_6$) was linearly related to the concentrations of surfactant as well as dimethomorph in spray solution, suggesting that it is simply a diffusion phenomenon of the solute molecule through a cuticular membrane from leaf surface. Octadecanol attached to FAE was most effective lipophile on the leaf penetration of dimethomorph. And, the more ethylene oxide had the polyoxyethylene chain of FAE up to 20 moles, the higher the uptake rate was. Therefore, the role of lipophile of FAE on dimethomorph penetration to cucumber leaf, probably, is to modify the physico-chemical properties of cuticular membrane to be permeable to dimethomorph, and the polyoxyethylene chain having less than 20 moles ethylene oxide, which is moderately permeable to cuticular membrane by its molar volume, is to let the physically-modified cuticular membrane to be maintained for a longtime.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.355-361
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• 1999

We have synthesized the soluble polymide based side chain system with covalently attached NLO chromophore Disperse Red 1. The developed polymer is optically transparent in the range of optical communication wave-lengths. Its glass transition temperature$(T_g)$ and thermal decomposition temperature$(T_d)$ are $225^{\circ}C, 310^{\circ}C$ respectively. The poled film with the poling field of $100 V/\mu\textrm{m}$ shows that the dielectric constant is 3.37 at the 10-kHz frequency, the refractive indices of TM and TE modes are both 1.631 at $\lambda = 1300 nm$, and the Electro-optic coefficients are 4.6~9.2 pm/V at $\lambda = 1300 nm$. There are no decays of the EO coefficient in the poled polymer at $180^{\circ}C$ in one hour, and $90^{\circ}C$ in 500 hours.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.2
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• pp.89-101
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• 2005

Research on highly abstracted system modeling and simulation has received a great deal of attention as of the concept of platform based design is becoming ubiquitous. From a practical design point of view, such modeling and simulation must consider the following: (i) fast simulation speed and cycle accuracy, (ii) early availability for early stage software development, (iii) inter-operability with external tools for software development, and (iv) reusability of the models. Unfortunately, however, all of the previous works only partially addresses the requirements, due to the inherent conflicts among the requirements. The objective of this study is to develop a new system design methodology to effectively address the requirements mentioned above. We propose a new transaction-level system modeling methodology, called ViP (Virtual Platform). We propose a two-step approach in the ViP method. In phase 1, we create a ViP for early stage software development (before RTL freeze). The ViP created in this step provides high speed simulation, lower cycle accuracy with only minor modeling effort.(satisfying (ii)). In phase 2, we refine the ViP to increase the cycle accuracy for system performance analysis and software optimization (satisfying (i)). We also propose a systematic ViP modeling flow and unified interface scheme based on utilities developed for maximizing reusability and productivity (satisfying (ii) and (iv)) and finally, we demonstrate VChannel, a generic scheme to provide a connection between the ViP and the host-resident application software (satisfying (iii)). ViP had been applied to several System-on-a-chip (SoC) designs including mobile applications, enabling engineers to improve performance while reducing the software development time by 30% compared to traditional methods.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.371-371
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• 2007

In this study, liquid crystal (LC) aligning capabilities for vertical alignment on the $CeO_x$ thin film by thermal evaporation method were investigated. Also, the control of pretilt angles and thermal stabilities of the NLC treated on $CeO_x$ thin film were investgated. The uniform LC alignment on the $CeO_x$ thin film surfaces and good thermal stabilities with thermal evaporation can be achieved. It is considerated that the LC alignment on the $CeO_x$ thin film by thermal evaporation is attributed to elastic interaction between LC molecules and micro-grooves at the $CeO_x$ thin film surface created by evaporation. In addition, it can be achieved the good electro-optical (EO) properties of the VA-LCD on $CeO_x$ thin film layer with oblique thermal evaporation.

• Korean journal of food and cookery science
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• v.7 no.3
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• pp.7-12
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• 1991

Castera is a favorite food which is well known to the general public made by egg, sugar and wheat flour. This study is carried out in order to investigate to the physical properties of eastern. The results are summarized as follows: 1) As a result of the sensory evaluation for eastern with 19 kinds of material in Kyushu on the market, it could be classified into 3 types: A) high grade (Castera), C) low grade (Sponge cake), and B) midium grade (Something middle of those). 2) In the texturometer measurement for eastern, hardness of A type was highest, B and C are 22∼35% lower than A type, while cohesiveness and springiness are not significantly different. 3) In the creep test, 3 types are all the S-element Voigt model, consisting of Hookean body, Newtonian body and two sets of Voigt body. Eo of A type is 13∼36% higher than other types, it tends to the same result of hardness. The parts of retardation strain of A type are 21∼41% lower than B type, 8∼l3% higher than C type, respectively. 4) About the day change of eastern of A type, mechanical model is not changed.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.221-229
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• 2016

Fifty-five specimens of Octopus longispadiceus, belonging to the family Octopodidae, were collected for the first time from the East Sea of Korea and identified by DNA barcoding. This species is characterized by its long right third arm and ligula, the presence of enlarged suckers in the mature male, small white spots on the mantle, head, and arms, and no cirrus above the eye. A molecular analysis of the partial cytochrome c oxidase subunit I gene showed that these specimens are all the same species and have the smallest genetic distance with O. longispadiceus (Kimura- two-parameter distance = 0.002-0.003). A new Korean name, "Bal-mun-eo" is proposed for this species.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.297-300
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• 2015

This is the first report of Champsodon longipinnis (Champsodontidae) collected from Korea. The specimen (100.9 mm in standard length) was caught by a bottom trawl in the coastal waters off Busan, Korea. This species is characterized by the following morphological traits: body with small denticulate scales except abdomen around pelvic fin base; posterior end of maxilla extending beyond margin of eye; dark pigmentation on most of the first dorsal fin, upper half of the first to the fourth soft ray of the second dorsal fin, and partial upper lobe of caudal fin. We add C. longipinnis to the Korean fish fauna and suggest a new Korean name, "Jeom-ak-eo-chi," for the species.