• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.3
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• pp.257-262
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• 2007

Organic light-emitting diodes (OLEDs) with the high efficieney and long lifetime are of growing interest in next-generation displays. Among the factors influencing OLEDs properties, one of unstable factor is $Alq_3$ cationic species caused by the excess holes resided in $Alq_3$ layer. Therefore, we suppressed the accumulation of excess holes by using the mixed-hole transporting layer (MHTL) of NPB and CBP in multilayer green OLEDs. The devices with MHTL showed improved characteristics in the luminous efficiency and lifetime. More characteristics and the carrier transport mechanism will be discussed.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.470-472
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• 2000

In this paper generation from of displacement current was compared and measured with light stimulus induce monolayers which 8A5H with azobenzene and arac.acid mixed. Light response of two monolayers which dynamics behavior are different was compared and measured though they are the same isomer The experimental results are as following; In the case of light stimulus mixed monolayers reacted less than 845H about 5[fA]. This is the mason molecule dynamic behaviour and trans was not activated due to its very chain length.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.403-406
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• 1998

Electroluminescence(EL) come from the light emission obtained by electrical excitation energy passing through a phosphor layer under applied high electrical field. The preparation and characterizations of light emitting ACPEL(alternating-current powder electroluminescent) cell based on two kinds of phosphor mixed ZnS:Mn, Cu and ZnS:Cu phosphor. Basic structure is ITO/Mixed Phosphor/insulator/Al sheet, each layer was mixed by binder, which concentration 11p for phosphor, 8p for insulator. Dielectric properties was investigated first and emission properties of P-LED based on ZnS:Mn,Cu/ZnS:Cu,Br mixture. Emission spectra exhibits two kinds of main peaks at 100V, 1kHz sinusoidal excitation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.67-68
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• 2006

Organic light-emitting devices (OLEDs) with the high efficiency and long lifetime are of growing interest in next-generation displays. Among the factors influencing OLEDs properties, one of unstable factor is $Alq_3$ cationic species caused by the excess holes resided in $Alq_3$ layer. Therefore, we suppressed the accumulation of excess holes by using the mixed-hole transporting layer (MHTL) of NPB and CBP in multilayer green OLEDs. The devices with MHTL showed improved characteristics in the luminance efficiency and lifetime. More characteristics and the carrier transport mechanism will be discussed.

• Journal of the Korea Computer Graphics Society
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• v.22 no.3
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• pp.89-99
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• 2016

One of the fundamental elements in developing mixed reality applications is to effectively analyze and apply the environmental lighting information to image synthesis. In particular, interactive applications require to process dynamically varying lighting sources in real-time, reflecting them properly in rendering results. Previous related works are not often appropriate for this because they are usually designed to synthesize photorealistic images, generating too many, often exponentially increasing, light sources or having too heavy a computational complexity. In this paper, we present a fast light source estimation technique that aims to search for primary light sources on the fly from a sequence of video images taken by a camera equipped with a fisheye lens. In contrast to previous methods, our technique can adust the number of found light sources approximately to the size that a user specifies. Thus, it can be effectively used in Phong-illumination-model-based direct illumination or soft shadow generation through light sampling over area lights.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04a
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• pp.67-68
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• 2008

A simple bi-layer structure of organic light emitting diode (OLED) was used to study the characteristics of anode preparation. Indium tin oxide (ITO) anode surface treatment of OLEDs was performed to get the optimum condition for the ITO anode. The ITO surface was treated by $O_2$ or $O_2$ / Ar mixed gas plasma with different processing time. The electrical characteristics of OLED were improved by plasma treatment. The operating voltage of OLED with $O_2$ or $O_2$/Ar mixed gas plasma treated anodes decreases from 8.2 to 3.4 V and 3.2V, respectively. The $O_2$ /Ar mixed gas plasma treatment results in better electrical property.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.1
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• pp.79-85
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• 1999

Use of soils with crushed expanded polystyrene(EPS) satisfied both recycling of industrial waste and development of new light-weight fill materials. Objectives of the study were to make the mixed the mixed soils with the crushed EPS and to suggest the most rational mixing ration as a fill material. A series of laboratory tests was performed to investigate the relationship between miximum dry density and optimum moisture contenr and to find the variation of CBR for mixtures with 3 soils and 2 sizes of the crushed EPS. Results of the test showed that the sizes fo the curshed EPS had a little effect on the properties of mixed soils. But gradatiion of soils and mixing ration with the crushed EPS were important factors to characterize compaction properties of the mixed soils.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.127-134
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• 1999

This study was performed to obtain the basic data to present rational silvicultural tending plan. It makes these widely distributed pine-oak mixed stand and each of pure stand in middle province on object of this study and do comparative analysis of light condition about stand parameter and natural regeneration according to each slope(north, west and south) conditions of location in central part of South Korea. Sample plots for pine-oak mixed stand and pine and oak pure stand were established on each of southern, northern and western slopes based upon site and growth conditions of the slope. Sample plot was a circle of 0.05ha with a diameter of 25.24 m. A sample plot has between 30 and 40 tree in it. Total 23 sample plots were established; 9 pure pine stands, 8 pine-oak mixed stands. and 6 pure oak stands across lower, middle, upper parts of slopes. Relative light intensity within a stand was' measured by crown- photo(fish-eye lens; 180$^{\circ}$) system through fish-eye lens and by comparing each plot with the denuded through PAR-sensor. The crown closure ratio of pure pine stand (75%) shows much lower than that of mixed stand (90.9%) and pure oak stand (93%). The relative light intensity within a stand showed an opposite result. The crown closure of mixed stands tended to become gradually low as the slope moves from the north to the south, but the relative light Intensity within the stand tended to rise. By analyzing the relationship between the relative light intensity within a stand and stand parameter, light intensity within a stand tended to decrease as the diameter and N/ha increase. Number of oak seedlings and light intensity within a stand is in a straight-line regression relation. In particular, the number of oak seedlings was the highest in mixed stands on the southern slope. But no single pine seedling was found. The unfavorable conditions of l0cm thick litter layer and low relative light intensity in a stand (ranging between 4% and 8%) is considered to prevent pine seeds from germinating.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.615-620
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• 2000

The strength properties of Light-Weighted Soils(LWS) mixed with Expanded Polystrene(E.P.S) are studied. Test results show that when the initial water contents of dredged soils are under 135% and the cement contents are above 1%, Light-Weight Soils are in the appropriate strength range of 2.0 to 4.0kg/㎠. However, E.P.S contents had a little affects on the strength properties of LWS. In the view of E.P.S diagram's effects on LWS, which have expand ratio of 25, 35, 45 and 60, further studies considering of physical properties of original E.P.S beads are needed.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.245-256
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• 2015

In the agricultural industries, LEDs are used as supplementary, as well as main lighting sources in closed cultivation systems. In cultivation using artificial light sources, various light qualities have been tried to supplement fluorescent lamps to promote plant growth and metabolism. Microarray analysis of Brassica rapa seedlings under blue and fluorescent mixed with blue light conditions identified changes in three genes of the glucosinolate pathway. This attracted attention as functional materials highly expressed 3.6-4.6 fold under latter condition. We selected four more genes of the glucosinolate pathway from the Brassica database and tested their expression changes under fluorescent light mixed with red, green, and blue, respectively. Some genes increased expression under red and blue mixed conditions. The Bra026058, Bra015379, and Bra021429; the orthologous genes of CYP79F1, ST5a, and FMOGS-OX1 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with blue light conditions. Further, Bra029355, Bra034180, Bra024634, and Bra022448; the orthologous genes of MAM1, AOP3, UGT74B1, and BCAT4 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with red light conditions. The various light conditions had unique effects on the varieties of Brassica, resulting in differences in glucosinolate synthesis. However, in some varieties, glucosinolate synthesis increased under mixed blue light conditions. These results will help to construct artificial light facilities, which increase functional crops production.