• Journal of the Korean Ceramic Society
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• v.48 no.3
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• pp.251-256
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• 2011

The luminescence properties of polycrystalline ZnO annealed in reducing ambience ($H_2/N_2$) have been studied. An effective quenching of green luminescence with enhanced UV emission from polycrystalline ZnO is observed for the reduced ZnO. The variations of the UV and green luminescence band upon reduction treatment are investigated as a function of temperature in the range between 20 and 300 K. Upon annealing treatment in reducing ambience, the optical quality of polycrystalline ZnO is improved. The UV to green intensity ratio of sintered ZnO approaches close to zero (~0.05). However, this ratio reaches more than 13 at room temperature for polycrystalline ZnO annealed at $800^{\circ}C$ in reducing ambience. Furthermore, the full width at half maximum (FWHM) of the UV band of polycrystalline ZnO is reduced compared to unannealed polycrystalline ZnO. Electron paramagnetic resonance (EPR) measurements clearly show that there is no direct correlation between the green luminescence and oxygen vacancy concentration for reduced polycrystalline ZnO.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.107-112
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• 2022

This study was conducted to investigate the effects of mulching materials in extensive green roof system by comparing and analyzing the soil moisture content and growth response of Lychnis cognata according to the types of organic mulching materials. The experimental group consisted of a control group that did not use mulching material (Cont.) and a total of five treatment groups, including cocochip (C.O), woodchip (W.O), straw (S.T), and sawdust (S.A), depending on the mulching material. The soil moisture content according to the type of organic mulching material was high in the order of W.O > S.T > Cont. > C.O > S.A, and there was a significant difference especially in S.A. The plant height showed good growth in the order of S.T > Cont. > C.O > W.O > S.A, and there was no significant difference by mulching materials in other growth items except for plant height. Both the chlorophyll and plant water contents were superior to those of untreated group, so the treatment of organic mulching materials is considered to be effective in maintaining the chlorophyll and plant water contents of Lychnis cognata. In particular, the soil moisture content was affected by the characteristics of the mulching material itself. Based on these results, it is required to use a mulching material suitable for the characteristics of each plant in extensive green roof system and it is considered that this can be overcome through organic mulching when selecting a plant species that is weak to water stress.

• Composites Research
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• v.32 no.2
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• pp.96-101
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• 2019

Interfacial adhesion between fiber and resin are related to composites performance, so it is very important to evaluate them accurately. In this study, the interfacial properties of microdroplets under fatigue loading conditions were evaluated. The mechanical properties and interfacial adhesion of epoxy resin with dopamine were studied. Tensile specimens were prepared to evaluate mechanical properties and epoxy microdroplets specimens were used for the evaluation of interfacial adhesion. In addition, in the microdroplet fatigue test, the same diameter of the microdroplet was used and the experiment was performed under the same conditions. As a result, it was confirmed that mechanical and interfacial properties were improved when dopamine was applied to epoxy resin through tensile and microdroplet experiments. It is considered that dopamine improves the degree of curing of the epoxy resin and imparts hydroxyl groups to the epoxy resin to increase the mechanical properties and the interfacial adhesion between the glass fibers.

• Journal of Information Display
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• v.8 no.1
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• pp.10-13
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• 2007

We synthesized new blue and bluish green emitting materials by using fully substituted ethylene moieties. Multi-layered EL devices were fabricated with synthesized materials and evaluated in terms of emission color and luminescence efficiency. TBBPE[EML 2] device showed bluish-green CIE value of (0.236, 0.412) and 5.02cd/A at $10mA/cm^2$. BPBBPE[EML 3] device also showed sky-blue CIE value of(0.218, 0.355) and 2.31cd/A at $l0mA/cm^2$.

• Korean Journal of Materials Research
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• v.14 no.12
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• pp.889-892
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• 2004

The synthesis of $Zn_{2}SiO_4:Mn^{2+}$ for PDP green phosphor by SHS(Self-propagating High temperature Synthesis method) was studied. The precursors were well mixed and cold compacted. And then, the green pellet was synthesized at high temperature through self-propagating high temperature zone. Because this reaction uses the heat resulted from the oxidation of Zn metal powder in this system, Zn/ZnO mole ratio is one of the most important reaction variable. Throughout several experiments, the optimal condition of Zn/ZnO mole ratio and Mn concentration are 1.2/0.8 and 0.05mo1e, respectively.

• Journal of the Korean Ceramic Society
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• v.40 no.1
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• pp.1-4
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• 2003

To study the effect of aggregates on the microstructure of sintered bodies, Mn-Zn ferrite powders were prepared by an alcoholic dehydration method. Aggregate powders and reground powders were used as seeds and matrices, respectively. The mixing ratios for the aggregate and reground powders were varied with the sintering temperatures. Green densities were measured with changes in forming pressure and they were related to the microstructures of the sintered bodies. The aggregates proved to be capable of acting as seeds for abnormal grain growth. When the green density difference between the aggregate and the matrix was large, the aggregate could become the seed of abnormal grain growth. As the forming pressure increased, the more aggregates became seeds of abnormal grain growth.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.106-113
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• 2012

As environmental pollution and resource exhaustion have been considered as social issues, interest in green content industries which lead low-carbon green growth is increasing. In various areas, green content products and programs have been presented. Of them, kid theme parks are designed to recognize fun and advantages eco-friendly consumption with green contents has and lead children to recognize the problems of environmental pollution and the importance of environment. This study aims to analyse kid theme parks using green contents and characteristics of their space representation. The analysis frame was made through theoretical examination for bibliographical data and a direct interview in terms of factors of green contents. For the analysis frame, visitors were directly interviewed from June to July, 2012. Cases of introduction were analysed to identify realization and characteristics of green contents. As a result of the analysis, it was discovered that kid theme parks using green contents pursued green stories, but they did not consider environment seriously in terms of content materials and methods of realization. To develop successful kid theme parks using green contents, multi-dimensional research is needed in various aspects and various contents such as media should be introduced. The parks should provide fun space for children and propagate green ideas. Its success can lead in green entertainment. The study will be helpful for design of future kid theme parks.

• Genomics & Informatics
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• v.13 no.3
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• pp.81-85
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• 2015

Molecular characterization technology in genetically modified organisms, in addition to how transgenic biotechnologies are developed now require full transparency to assess the risk to living modified and non-modified organisms. Next generation sequencing (NGS) methodology is suggested as an effective means in genome characterization and detection of transgenic insertion locations. In the present study, we applied NGS to insert transgenic loci, specifically the epidermal growth factor (EGF) in genetically modified rice cells. A total of 29.3 Gb (${\sim}72{\times}coverage$) was sequenced with a $2{\times}150bp$ paired end method by Illumina HiSeq2500, which was consecutively mapped to the rice genome and T-vector sequence. The compatible pairs of reads were successfully mapped to 10 loci on the rice chromosome and vector sequences were validated to the insertion location by polymerase chain reaction (PCR) amplification. The EGF transgenic site was confirmed only on chromosome 4 by PCR. Results of this study demonstrated the success of NGS data to characterize the rice genome. Bioinformatics analyses must be developed in association with NGS data to identify highly accurate transgenic sites.

• Journal of the Korean Society of Floral Art and Design
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• no.40
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• pp.45-61
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• 2019

This study attempts to examine the recent trend of 'Maison & Objet' exhibition which shows everything that forms a space, and seek cases where such 'green amenity' is applied. In terms of morphology, a minimal space was filled with a curved shape, and gradually a design that reproduces nature was produced. As the maximalism gradually emerged, decorative elements were added to the design, and a lot of craft products appeared. In terms of materials, the emotion of naturalism was the most common, and natural wood materials were mainly used. These materials combine with various heterogeneous materials to complete a new design, and natural elements were shaped in space. In terms of colors, the theme in 2016 was 'Wild', and it was possible to see a space where wild nature can be experienced. It showed various colors of nature centered on brown and green of trees. 'Silence' in 2017 is distinguished and characterized by its pink color. Also, pieces of warm reddish brown furniture were made. In the past, brass or rose gold would be trendy, but in 2017, gold or silver colors showed a greater popularity. In 2018, 'Show Room' was the theme, and the representative color was green, which affected new designs with yellow and pink.

• Korean Institute of Interior Design Journal
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• v.22 no.2
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• pp.176-185
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• 2013

(Background)In modern industrial society, the design industry failed to observe the law of nature, destructing it. Regardless its intention, the design industry destructed the environment so that it can't maintain the future life because of waste and disaster. For the purpose, it is important to adopt the technology to reuse the waste resource generated by building or minimize the damage to environment for the resource that can't be recycled. (Methods)On the assumption that the material and resource can be an alternative plan for the design that can make environment be sustained, the study analyzed materials and resources out of superior office space of USA, which were selected by LEED Green Building Rating System. (Results)The analysis result revealed that all cases reused main structural part of existing building and indoor and various materials were reused or recycled. Especially, the materials without or with low amount of VOCs and formaldehyde were used. In order to reduce construction waste, the finish of existing building was exposed as it was, 50% of reused materials were used or disassemblable materials were used. When regional materials are used, there is an advantage to reduce transportation cost and recycle the materials rapidly. Lastly, the environment-friendly certified by FSC was used in all cases. (Conclusion)After all, the material is one of the space design strategies sensitive to environment so it is important to select good material. Harmless, environment-friendly materials applied to sustainable office space contribute to the creation of healthy environment. In addition, the use of recycled materials and reused materials to minimize waste is also essential factor for creating sustainable space.