• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.1
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• pp.45-49
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• 1983

The four-layered(metal/insulator/n epi-layer/p+) controlled inversion devices have been fabricated. The I-V curve showed two characteristic states―an On state and an OFF state which were separated by a negative resistance region. The switching voltage and the holding voltage were about 5.0V and 2.5V, respectively. The switching voltage of the device was decreased by photo illumination while the holding voltage remained unaffected.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.2
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• pp.163-170
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• 1995

The STEM II(Sulfur Transport Eulerian Model II) was adapted to investigate air pollutant transport phenomena between Eastern China and Korea. The movement of the high concentration region was clearly identified for the sulfate but was mot visible for SO$_{2}$. The 10.sim. 16 times more amount of SO$_{2}$ is transported to Korea compared to that of the local emission while the amount of the sulfate transported to Korea is 1 .sim. 1.3 times more than that of the sulfate produced by photo-chemical reaction in Korea. APTIs(Air Pollutant Transport Indices) for SO$_{2}$ and sulfate are approximately 0.85, which implies that the most of the SO$_{2}$ and sulfate existed in Korea are transported from Eastern China.

• Journal of Environmental Science International
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• v.27 no.3
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• pp.227-231
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• 2018

We studied the warming effect induced by Photovoltaic(PV) power plants in rural areas during summer daytime using a simple analytical urban meteorological model. This analysis was based on observed meteorological elements and the capacity of the PV power plant was 10 MWp. The major axis length of the PV power plant was assumed to be 1km. Data of the necessary meteorological elements were obtained from a special meteorological observation campaign established for a over a PV power plant. We assumed that the wind flowed along the major axis of the PV power plant(1 km). As a result, the air temperature on the downwind side of the PV power plant was estimated to invrease by about $0.47^{\circ}C$.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.531-531
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• 2012

So many groups have been researching the green quantum dots such as InP, InP/ZnS for overcoming the semiconductor nanoparticles composed with heavy metals like as Cd and Pb so on. In spite of much effort to keep up CdSe quantum dots, it does not reach the good properties compared with CdSe/ZnS quantum dots. This quantum dot has improved its properties through the generation of core/shell CdSe/ZnS structure or core/multi-shell structures like as CdSe/CdS/ZnS and CdSe/CdS/ CdZnS/ZnS. In this research, we try to synthesize the InP multi-shell structure by the successiveion layer absorption reaction (SILAR) in the one pot. The synthesized multi-shell structure has improved quantum yield and photo-stability. To generate white light, highly luminescent InP multi-shell quantum dots were mixed with yellow phosphor and integrated on the blue LED chip. This InP multi-shell improved red region of the LEDs and generated high CRI.

• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.543-545
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• 2006

Surface photovoltage (SPV) measurements were performed to investigate the optic-electrical properties in the electron beam irradiation semi-insulating GaAs (e-beam irradiation SI-GaAs) and semi-insulating GaAs (SI-GaAs). The signal intensity showed stronge. dependency on the frequency in the SI-GaAs than it did in the e-beam irradiation SI-GaAs. This result indicates that the number of the generated photo-carriers depends on the surface state. Also, the B region of the e-beam irradiation SI-GaAs found a weak signal. This result was explained by the surface and internal damage with e-beam irradiation.

• Journal of the Semiconductor & Display Technology
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• v.16 no.1
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• pp.65-69
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• 2017

This paper presents a Technology-CAD (TCAD) simulation of the characteristics of crystalline Si pillar array solar cells. The junction depth and the surface concentration of the solar cells were optimized to obtain the targeted sheet resistance of the emitter region. The diffusion model was determined by calibrating the emitter doping profile of the microscale silicon pillars. The dimension parameters determining the pillar shape, such as width, height, and spacing were varied within a simulation window from ${\sim}2{\mu}m$ to $5{\mu}m$. The simulation showed that increasing pillar width (or diameter) and spacing resulted in the decrease of current density due to surface area loss, light trapping loss, and high reflectance. Although increasing pillar height might improve the chances of light trapping, the recombination loss due to the increase in the carrier's transfer length canceled out the positive effect to the photo-generation component of the current. The silicon pillars were experimentally formed by photoresist patterning and electroless etching. The laboratory results of a fabricated Si pillar solar cell showed the efficiency and the fill factor to be close to the simulation results.

• International Journal of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.81-87
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• 2018

It is common practice to display high-quality video images on the large display among the methods of developing tourist attractions and culture in the region as experience contents differentiation is required. This paper combines the local attractions with the OLED dual layer display system and the extended image implementation and augmented interaction technique to give the experiencer a realistic space, such as directing to new experiences and beautiful sights. In this paper, we added UI layer to additional layers of images to enable users to experience sightseeing information, weather, maps, accommodation, festivals and photo materials with images. It is implemented to add fun through interlocking. We also developed transparent OLED and dual layer panel and 3-channel multi-image playback technique.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.12
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• pp.1280-1289
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• 1991

The setting up and the characteristics of the reactive magnetron sputtering process are described and TiN thin film deposited by this system is studied in this paper. We have studied characteristics of the discharge voltage-current, electron temperature and density. With the variation of discharge current and magnetic field, partial pressure of NS12T that changed from Ti to TiN sputtering region has been investigated with experimental method. We have analyzed the physical characteristics of TiN thin film obtained under the various conditions in this sputtering process with SEM photo-analysis and X-ray diffraction pattern of these samples.

• Journal of Korea Multimedia Society
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• v.22 no.5
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• pp.527-534
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• 2019

Recently, Photo editing softwares such as digital cameras, Paintshop Pro, and Photoshop digital can create counterfeit images easily. Various techniques for detection of tamper images or forgery images have been proposed in the literature. A form of digital forgery is copy-move image forgery. Copy-move is one of the forgeries and is used wherever you need to cover a part of the image to add or remove information. Copy-move image forgery refers to copying a specific area of an image itself and pasting it into another area of the same image. The purpose of copy-move image forgery detection is to detect the same or very similar region image within the original image. In this paper, we proposed fast detection of forgery image using four step search based on discrete cosine transform and a four step search algorithm using discrete cosine transform (FSSDCT). The computational complexity of our algorithm reduced 34.23 % than conventional DCT three step search algorithm (DCTTSS).

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.792-797
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• 2018

We have explained the synthesis of novel phenanthrene and pyrene substituted phthalocyanines (PC-PHE and PC-PYR) and fully confirmed the structures by its spectral, photo physical and elemental analysis. For these phthalocyanines we checked the UV-Visible absorbance in PGMEA and chloroform and transmittance checked in PGMEA. The transmittance results suggested that these phthalocyanines are showing more than 90% transmittance at the 450-550 nm region. These synthesized molecules are nicely soluble in almost all industrial solvents. We checked the aggregation property of these phthalocyanines in PGMEA, and the results suggested no any aggregation for these molecules in PGMEA. The thermogravimetric analysis results concluded that PC-PHE and PC-PYR had high thermal stability. All studies explain that these new phthalocyanines are more suitable for LCD green color filter application.