• Current Photovoltaic Research
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• v.10 no.1
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• pp.16-22
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• 2022

The long-term stability of PSCs against visual and UV light, moisture, electrical bias and high temperature is an important issue for commercialization. In particular, since the operation temperature of solar cell can rise above 85℃, a study on thermal stability is required. In this study, the cause of thermal-induced degradation of PSCs was investigated using the SCAPS-1D simulation tool. First, PSCs of TiO₂/CH₃NH₃PbI₃/Spiro-OMeTAD/Au structure were exposed to a constant temperature of 85℃ to observe changes in conversion efficiency and quantum efficiency. Because the EQE reduction above 500 nm was remarkable, we simulated PSCs performance as a function of lifetime, doping density of perovskite and spiro-OMeTAD. Consequently, the main cause of thermal-induced degradation is considered to be the change in the perovskite doping concentration and lifetime due to ion migration of perovskite.

• The Korean Journal of Applied Statistics
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• v.34 no.5
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• pp.773-794
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• 2021

Prediction of vehicle traffic volume is very important in planning municipal administration. It may help promote social and economic interests and also prevent traffic congestion costs. Traffic volume as a time-varying trajectory is considered as functional data. In this paper we study three functional regression models that can be used to predict an unseen trajectory of traffic volume based on already observed trajectories. We apply the methods to highway tollgate traffic volume data collected at some tollgates in Seoul, Chuncheon and Gangneung. We compare the prediction errors of the three models to find the best one for each of the three tollgate traffic volumes.

• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2135-2139
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• 2008

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1314-1319
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• 2007

This study is to compare food components and the sensory properties of common and functional Porphyra yezoensis, Pyroligneous liquor, Salicornia herbacea L. and Salicornia herbacea L. treated with oak charcoal. The samples used in this study were provided by a local manufacturer. We analyzed their proximate composition, mineral content, heavy metal content and amino acids. We conducted the sensory evaluation before and after grilling Porphyra yezoenis. Common components are more plentiful in functional Porphyra yezoenis than in common except for carbohydrate and crude fiber. In the case of mineral content, generally functional Porphyra yezoensis contains much more mineral than common except for magnesium and zinc. Especially Salicornia herbacea L. treated with oak charcoal contains abundant iron. Also, Salicornia herbacea L. contains a lot of calcium potassium, copper and sodium. There is a little more heavy metal except for chromium, cadmium and lead in Salicomia herbacea L. treated with oak charcoal than in common that contains a lot of chromium, cadmium and lead, although a wide difference was not discovered between them. In the case of composed amino acid, there are much glutamic acid, glycine, isoleucine and phenylalanine in both Porphyra yezoensis. Especially alanine and phenylalanine are trebled in functional Porphyra yezoensis. Also, there are far more serine and lysine in Salicornia herbacea L. and Salicornia herbacea L. treated with oak charcoal than in common Porphyra yezoensis and Pyroligneous liquor. In the case of the sensory properties, there isn't a big difference before grilling Porphyra yezoensis; however, after grilling, most functional Porphyra yezoenis had good sensory properties results, especially Salicornia herbacea L. were better than Pyroligneous liquor.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.24-28
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• 2009

This study was conducted to evaluate the growth characters and yield components of 18 collected sesame cultivars to get basic information on the variation for the sesame breeding using principal component analysis. All characters except days to flowering, days to maturity and 1,000 seed weight showed significantly different. Seed weight per 10 are showed higher coefficient of variance. Capsule bearing stem length and liter weight showed positive correlation with seed yield per 10 are. The principal components analysis grouped the estimated sesame cultivars into four main components which accounted for 83.7% of the total variation at the eigenvalue and its contribution to total variation obtained from principal component analysis. The first principal component ($Z_1$) was applicable to increase plant height, capsule bearing stem length and 1,000-seed weight. The second principal component ($Z_2$) negatively correlated with days to flowering and maturity by which it was applicable to shorten flowering and maturity date of sesame. At the scatter diagram, Yangbaek, Ansan, M1, M2, M4, M7 and M9 were classified as same group, but M10, Yanghuk, Kanghuk, M5, M6, M12 and M13 were classified as different group. This results would be helpful for sesame breeder to understand genetic relationship of some agronomic characters and select promising cross lines for the development of new sesame variety.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.399-405
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• 2013

Two series of new green phosphorescent polymers bearing a bis(2-phenyl-pyridine)iridium(III)(dibenzoylmethane) [$(ppy)_2Irdbm$] complex were designed and synthesized. Poly-carbazole (PCbz) derivative or polyfluorene with pendant carbazole groups (PFCbz) were employed as host polymers for the iridium complex. The iridium complex monomer was copolymerized with the host monomers using varying monomer ratios via a Yamamoto coupling reaction. Efficient energy transfer from host to dopant unit was observed by increasing the ratio of the iridium guest in the copolymers. Electroluminescent devices with the configuration ITO/PEDOT:PSS/polymer/BmPyPB/LiF/Al were fabricated and characterized. The phosphorescent polymers composed of the iridium complex guest and polyfluorene with carbazole pendants as a host performed better than the polymers composed of the same guest and the main chain polycarbazole host. A maximum external quantum efficiency of 0.73%, a luminous efficiency of 1.21 cd/A, and a maximum luminance of 372 $cd/m^2$ were obtained from a device fabricated using one of the synthesized copolymers.

• Journal of KIISE:Software and Applications
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• v.33 no.1
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• pp.58-68
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• 2006

Requirements are very important to model software architecture. Requirements are divided into functional and quality requirements. Functional requirements are pinpointed subsystems and components. Quality requirements affect the structure of architecture. Thus requirements are essential to understand clearly in order to design software architecture. This paper focuses on a quantitative approach to requirements analysis for modeling architectures. In our proposal, functional requirements are quantified through calculating each priority of components. Quality requirements are quantified through calculating the correlation degree between components and quality attributes. The proposed method is implemented by DRAMA (Domain Requirements Analysis for Modeling Architectures), which fully supports our approach and are developed in Java environments. Our proposal is validated to apply some industrial examples.

• Membrane and Water Treatment
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• v.7 no.4
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• pp.341-353
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• 2016

Papermaking reconstituted tobacco is an important strategy for recycling the waste tobacco residues. To indentify the influences of the inorganic components on harmful components delivery in cigarette smoke, a self-made electrodialysis stack was assembled to desalt the tobacco extract. The influences of the applied current and extract content on the removal rate of the inorganic ions were investigated. Results indicated that the applied current was a dominant impact on the desalination performance. High currents lower than the limiting current density could accelerate the desalting efficiency but cause higher energy consumption. A current of 2 A, or current density of ${\sim}11mA{\cdot}cm^{-2}$, was an optimal choice by considering both the energy consumption and desalting efficiency. A 20% tobacco extract was an appropriate content for the electrodialysis process. More than 90% of inorganic ions could be removed under the optimum condition. The preliminary result indicated that removal of inorganic components was beneficial to decrease the harmful component delivery in cigarette smoke. Naturally, ED is an environmentally friendly and high-effective technology for desalting the tobacco extract.

• Journal of the Korean Society of Food Culture
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• v.36 no.2
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• pp.226-234
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• 2021

The purpose of this study was to investigate the changes in the content of functional components and the antioxidant activity of cooked rice and porridge composed of selected grains. The results of the study showed that brown rice and oat contained considerable amounts of γ-oryzanol (78.099~238.566 mg/100 g). However, cooked rice showed a decreased content of the same. The highest content of γ-aminobutyric acid (GABA) was observed in brown rice from Samgwang. The contents of biotin in all samples also decreased in cooked rice compared to raw cereal grains. The highest content of total polyphenols and flavonoids were observed in Heukjinmi rice, and the highest radical scavenging activity was also found in this variety. The cooking process led to a decrease in the content of functional components including γ-oryzanol, GABA, biotin, polyphenols, and flavonoids versus the corresponding raw cereal grains. These results may be useful in the development and application of home meal replacements using cereal grains.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.349-353
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• 2009

The effects of packaging materials on preserving the functional component of pine bud beverage stored under UV (ultraviolet) light exposure conditions were studied. The order of UV light blocking properties of the selected packages was: opaque can> opaque PET (polyethylene terepthalate) with green lamination=transparent PET with 10% PEN (polyethylene naphthalate) blending> transparent PET, and did not depend on film thickness in specified range. At 20${^{\circ}C}$, the order of preserving degree of original color and endobornyl acetate, which is quality index of pine bud beverage, was the same as above. Exposure to UV light can cause of deterioration of functional food components, but green color lamination and blending of PEN materials with transparent PET help to preserve the UV sensitive pine bud beverage components. However, the treated PET bottles have poorer preservation capabilities than the opaque cans. Transparent PET with PEN blending, in particular, will be very useful packaging material for colorful functional beverage preservation by helping to protect the ingredients while attracting consumer attention.