• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.251-257
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• 2011

Rice is the most important crop as a model plant for functional genomics of monocotyledons. Rice is usually transformed using Agrobacterium tumefaciens. However, the transformation efficiency using previous method is still low. In this study, we established a new method by modifying the general Agrobacterium protocol especially in the inoculation and co-cultivation step. We directly inoculated Agrobacterium containing a CIPK15 gene under the control of CaMV 35S promoter and NOS terminator in the pCAM1300 vector into the pre-soaked seeds in N6D media for 24 hours. After 7 days of culture at $25^{\circ}C$, calli were formed on seeds cultured on the co-cultivation medium containing an antioxidant compound (1 mM dithiothreitol) and of Agrobacterium growth-inhibiting agent (3 mg/L silver nitrate). We obtained 35 and 22 transgenic plants in rice cultivars, Gopumbyeo and Ilpumbyeo, with increase of transformation efficiency by 30.4% and 22.6%, respectively compared to the general transformation method. The new method in this study would lead to reduction of substantial labor and time to generate transgenic plants.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.493-493
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• 2014

The manufacturing cost of thin-film photovoltics can potentially be lowered by minimizing the amount of a semiconductor material used to fabricate devices. Thin-film solar cells are typically only a few micrometers thick, whereas crystalline silicon (c-Si) wafer solar cells are $180{\sim}300\mu}m$ thick. As such, thin-film layers do not fully absorb incident light and their energy conversion efficiency is lower compared with that of c-Si wafer solar cells. Therefore, effective light trapping is required to realize commercially viable thin-film cells, particularly for indirect-band-gap semiconductors such as c-Si. An emerging method for light trapping in thin film solar cells is the use of metallic nanostructures that support surface plasmons. Plasmon-enhanced light absorption is shown to increase the cell photocurrent in many types of solar cells, specifically, in c-Si thin-film solar cells and in poly-Si thin film solar cell. By proper engineering of these structures, light can be concentrated and coupled into a thin semiconductor layer to increase light absorption. In many cases, silver (Ag) nanoparticles (NP) are formed either on the front surface or on the rear surface on the cells. In case of poly-Si thin film solar cells, Ag NPs are formed on the rear surface of the cells due to longer wavelengths are not perfectly absorbed in the active layer on the first path. In our cells, shorter wavelengths typically 300~500 nm are also not effectively absorbed. For this reason, a new concept of plasmonic nanostructure which is NPs formed both the front - and the rear - surface is worth testing. In this simulation Al NPs were located onto glass because Al has much lower parasitic absorption than other metal NPs. In case of Ag NP, it features parasitic absorption in the optical frequency range. On the other hand, Al NP, which is non-resonant metal NP, is characterized with a higher density of conduction electrons, resulting in highly negative dielectric permittivity. It makes them more suitable for the forward scattering configuration. In addition to this, Ag NP is located on the rear surface of the cell. Ag NPs showed good performance enhancement when they are located on the rear surface of our cells. In this simulation, Al NPs are located on glass and Ag NP is located on the rear Si surface. The structure for the simulation is shown in figure 1. Figure 2 shows FDTD-simulated absorption graphs of the proposed and reference structures. In the simulation, the front of the cell has Al NPs with 70 nm radius and 12.5% coverage; and the rear of the cell has Ag NPs with 157 nm in radius and 41.5% coverage. Such a structure shows better light absorption in 300~550 nm than that of the reference cell without any NPs and the structure with Ag NP on rear only. Therefore, it can be expected that enhanced light absorption of the structure with Al NP on front at 300~550 nm can contribute to the photocurrent enhancement.

• Korean Institute of Interior Design Journal
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• no.25
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• pp.229-235
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• 2000

Although Frank Lloyd Wright represents himself as one of the greatest American master architect, the master architects contribution towards the advancement in the modern history of architecture goes beyond just creating landmark buildings. Through out his life, he was the leading architect not only in the area or architectural design but showed his talent in interior architecture, furniture, fabric, lighting fixture, art glasses, tablewares, silver wares as well as in graphic design which should cover all the elements related to the "total design" in architecture. As seen in his architectural design, the "total design" concept also reflects both beauty and logic of the nature and strengthens his theory of the organic architecture design. The research began with finding out the relationship between his architecture, nature and the supporting design elements mentioned above. the purpose of the research is to analyze the relationship of the spatial organization and the design elements in Frank Lloyd Wrights architectural works from the point of "total design" view and provide the valuable guide line for the development of the modern interior design. His design theory, based on the fundamental ideas of the nature, his organic architecture design, and reference materials to support total design concept will be discussed on chapter 2. And on chapter 3, application of the total design in his actual project will be analyzed. The data and analyzation have been completed based on written references and actual visit to the project sites. Frank Lloyd Wright placed highest value on the human beings and enjoyed presenting new ideas and forms to create better environment for the humans through his architecture and interior design projects. While he was presenting new ideas he continued to support design for democracy which has close relationship to the new frontier spirit of America. He was the master architect for the general society with accurate understanding of the life style of the public with design sensitivity shown in his concept of the total design.s concept of the total design.

• Korean Journal of Human Ecology
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• v.13 no.1
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• pp.173-183
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• 2004

The techno fashion presents the new formative beauty of fashion with a stream of light and dynamic phenomenon on human body. Also it opens the futurism arising from the combination of technology with fashion. The purpose of this paper was to investigate the internal trend and external form that techno-fashion aims at, and to analyze the expressive characteristics in design. The results were as follows. ${\cdot}$ The techno fashion created the new formative artifact through the dismantlement and reorganization of form. ${\cdot}$ The techno fashion used the composition of the geometrical abstraction as an expression of beauty symbolizing the modernity. ${\cdot}$ The techno fashion created the diverse colors by using the light along with colors of gold, silver, metal, intense fundamental colors, and artificial rotor. ${\cdot}$ The techno fashion expressed the dynamism, brilliance, youthfulness, futuristic image by using the sense of dazzling brightness by means of metal. ${\cdot}$ The techho fashion along with the development of science and technology made the atmosphere of silhouette of clothes different by expanding the category of materials more widely, together with the possibility of continual emergence of new material. ${\cdot}$ The techno fashion expressed the dynamic movement on clothes and gave the sense of periodical rhythm by the reflective action of light when they were clad. ${\cdot}$ The techno fashion grafted wearable technology into the fashion and made the information instruments recognized as a concept of clothes. ${\cdot}$ The techno fashion pursued the values of not only the beauty of the simple geometrical design, but also the values of functionality and expressed the image of high quality of life through the harmony of technology with human.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.4
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• pp.446-454
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• 2017

Recently, there have been many studies on bulk-fill resin composites. However, studies on the proper materials for pediatric patients are rare. The aim of this study was to compare the cavity wall adaptation of bulk-fill resin composites with conventional resin composite in class II cavities of primary molars using microcomputed tomography (micro-CT). Standardized class II slot cavities were prepared in 80 exfoliated primary molars and randomly divided into 4 groups. The control group was restored with conventional resin composite, Filtek Z-350 XT (FZ), and the three groups were restored with bulk-fill resin composites, Filtek bulk-fill posterior (FB), Tetric N-Ceram Bulk Fill (TNC), Filtek bulk-fill flowable (FBF). All specimens were thermocycled and then immersed in 50% silver nitrate ($AgNO_3$) solution. Micro-CT was used to measure the penetration volume of the total silver nitrate and the degree of cervical marginal leakage and the number, size, and position of the voids were evaluated. The results revealed that the volume of silver nitrate were significantly different between FB and FZ (p < 0.05). The results also revealed that the penetration length of silver nitrate FBF showed statistically lower than the FZ and FB (p < 0.05). There was no significant difference between the groups in number and size of voids. In conventional resin composite, most of the voids were present inside the restoration (83.3%), but the voids in the bulk-fill resin composites incidence were higher in the gingivoaxial angle. The cavity wall adaptation demonstrated in class II restorations of primary molar by new bulk fill resin composites was similar to conventional incremental technique. Bulk-fill resin composites might be an clinical option for a faster restoration in deciduous teeth.

• Smart Media Journal
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• v.11 no.9
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• pp.21-29
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• 2022

Ultra Violet(UV) is gradually being replaced with LED instead of general UV lamps. However, the light efficiency of UV LED is still lower than that of the general lamp, and the light efficiency is also low. Due to the current environment and technical problems of UV lamps, the LED replacements are gradually being made. In this study, a new package design and analysis were performed to increase the lifetime and performance of UV LEDs. A new packaging for UV LED were designed and implemented. The new packaging for UV LED was constructed to improve light efficiency. And the electrical and optical characteristics were analyzed respectively. To improve the optical efficiency in UV LED package, the Al has been used based on high reflectivity and applying the optimal lens focusing. Compared to the existing silver Ag, the light efficiency was improved by about 30% or more, and it was confirmed that the light output degradation characteristic was improved by about 10% in the newly applied optical device chip.

• Journal of the Optical Society of Korea
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• v.10 no.3
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• pp.130-142
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• 2006

Lab-on-a-chip technology is attracting great interest because the miniaturization of reaction systems offers practical advantages over classical bench-top chemical systems. Rapid mixing of the fluids flowing through a microchannel is very important for various applications of microfluidic systems. In addition, highly sensitive on-chip detection techniques are essential for the in situ monitoring of chemical reactions because the detection volume in a channel is extremely small. Recently, a confocal surface enhanced Raman spectroscopic (SERS) technique, for the highly sensitive biological analysis in a microfluidic sensor, has been developed in our research group. Here, a highly precise quantitative measurement can be obtained if continuous flow and homogeneous mixing condition between analytes and silver nano-colloids are maintained. Recently, we also reported a new analytical method of DNA hybridization involving a PDMS microfluidic sensor using fluorescence energy transfer (FRET). This method overcomes many of the drawbacks of microarray chips, such as long hybridization times and inconvenient immobilization procedures. In this paper, our recent applications of the confocal Raman/fluorescence microscopic technology to a highly sensitive lab-on-a-chip detection will be reviewed.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.137-141
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• 2010

Generally, polymer materials are not air-permeable and hydrophilic. In addition, they do not possess anti-fungal property. Hydrophilicity, air-permeability, and anti-fungal properties of new composites consisting of polymer, ceramic nanoparticles, and silver ion were investigated by contact angle measurements, air permeation time, and cell culture. The hydrophilic, air-permeable, and anti-fungal composites can be used in health care industry.

• Journal of Powder Materials
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• v.20 no.2
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• pp.120-124
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• 2013

This study is carried out to develop the new process for the fabrication of ultra-fine electrodes on the flexible substrates using superhydrophobic effect. A facile method was developed to form the ultra-fine trenches on the flexible substrates treated by plasma etching and to print the fine metal electrodes using conductive nano-ink. Various plasma etching conditions were investigated for the hydrophobic surface treatment of flexible polyimide (PI) films. The micro-trench on the hydrophobic PI film fabricated under optimized conditions was obtained by mechanical scratching, which gave the hydrophilic property only to the trench area. Finally, the patterning by selective deposition of ink materials was performed using the conductive silver nano-ink. The interface between the conductive nanoparticles and the flexible substrates were characterized by scanning electron microscope. The increase of the sintering temperature and metal concentration of ink caused the reduction of electrical resistance. The sintering temperature lower than $200^{\circ}C$ resulted in good interfacial bonding between Ag electrode and PI film substrate.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.375-382
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• 2015

We discovered three soil ciliates of the class Colpodea-Colpoda henneguyi Fabre-Domergue, 1889; C. lucida Greeff, 1888; and Bursaria truncatella $M{\ddot{u}}ller$, 1773 from Obong-ri, Ayajin-ri and Elwang-ri (Korea), respectively. Colpoda henneguyi had the following features: often wider preorally than postorally, size in vivo $60-80{\mu}m{\times}50-70{\mu}m$; extrusomes indistinct in vivo, cylindroid approximately $1{\mu}m$ long; notches caused by deep diagonal groove; yellowish globules on the cortex of the cell; 10-12 postoral kineties; silverline system aspera-type. Colpoda lucida exhibited the following features: broadly reniform, size in vivo $70-90{\mu}m{\times}50-70{\mu}m$; conspicuous extrusomes, $3.5-5{\mu}m$ long in vivo, cylindroid to fusiform; 13-16 postoral kineties; silverline system cucullus-type. Bursaria truncatella had the following features: bursiform, size in vivo $300-470{\mu}m{\times}120-260{\mu}m$; macronucleus coiled with highly variable shapes, $600-1100{\mu}m{\times}30-40{\mu}m$ long in vivo; micronuclei 16-25 in number, approximately $4{\mu}m$ in diameter; extrusomes cylindroid, $3-4{\mu}m$ long in vivo. This is the first report of colpodean ciliates from Korea, and we describe these species based on observations of live and impregnated (protargol and silver nitrate impregnation) specimens.