• 한국콘텐츠학회논문지
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• 제12권12호
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• pp.639-646
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• 2012

본 논문에서는 HP 컬러 레이저 프린터 기기의 출력물에 나타나는 Yellow Dots의 형태를 분석하고자, 각각 시간의 경과, 연과 월의 경과 그리고 동일한 기종에 따른 Yellow Dots의 특성을 실험하였다. 그 결과, 동일한 프린터기기의 출력물에서는 시간의 경과, 연과 월의 경과에서 나타나는 Yellow Dots의 형태가 동일한 것을 알 수 있었다. HP 컬러 레이저젯 프린터 기기에는 Xerox사에서 출시된 컬러 레이저젯 프린터기기와는 다르게 시간과 날짜 정보가 임베딩 되지 않았다는 것을 가정 할 수 있었다. 또한 시리얼 넘버가 다른 프린터기기에서는 유사하지만 다른 형태의 Yellow Dots가 나타나는 것을 알 수 있었으며, 이것은 프린터기기 구분에 있어 큰 도움이 된다. 마지막으로 실험에 사용된 모든 HP 컬러 레이저 프린터 기기들의 Yellow Dots를 분석한 결과, 동일한 패턴을 찾을 수 있었으며, 그 결과를 통하여 제조사를 파악 할 수 있었다. 향후 Yellow Dots 패턴을 해독하고 나아가 타 제조사의 Yellow Dots를 검출 및 분석하는 연구가 진행되어져야 한다.

• 한국재료학회지
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• 제31권1호
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• pp.16-22
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• 2021

In this study, quantum dot-sensitized solar cells (QDSSC) using CdSe/ZnS quantum dots (QD) of various sizes with green, yellow, and red colors are developed. Quantum dots, depending their different sizes, have advantages of absorbing light of various wavelengths. This absorption of light of various wavelengths increases the photocurrent production of solar cells. The absorption and emission peaks and excellent photochemical properties of the synthesized quantum dots are confirmed through UV-visible and photoluminescence (PL) analysis. In TEM analysis, the average sizes of individual green, yellow, and red quantum dots are shown to be 5 nm, 6 nm, and 8 nm. The J-V curves of QDSSC for one type of QD show a current density of 1.7 mA/㎠ and an open-circuit voltage of 0.49 V, while QDSSC using three type of QDs shows improved electrical characteristics of 5.52 mA/㎠ and 0.52 V. As a result, the photoelectric conversion efficiency of QDSSC using one type of QD is as low as 0.53 %, but QDSSC using three type of QDs has a measured efficiency of 1.4 %.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.588-590
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• 2008

Yellow-emitting $Y_3Al_5O_{12}$:Ce nanocrystalline phosphor and orange-emitting CdS:Mn/ZnS core/shell quantum dots were prepared by a modified polyol and a reverse micelle chemistry, respectively. To compensate a poor color rendering index of YAG:Ce nanocrystalline phosphor due to the lack of red spectral component, CdS:Mn/ZnS quantum dots were blended into YAG:Ce. Based on spectral evolutions in the blended systems, hybrid white light emitting diodes are fabricated and characterized.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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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.

• 대한전자공학회논문지SP
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• 제40권1호
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• pp.1-9
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• 2003

본 논문에서는 밝은 영역에서 K(Black) 대신에 C(Cyan), M(Magenta), Y(Yellow)를 공간적으로 흩어서 출력하는 새로운 방법을 제안하였다. 어두운 영역에서 검은 점의 겹침은 밝기값을 감소시키며 밝은 영역에서의 검은 점은 인간 시각 체계에 민감하다. 따라서 이러한 문제를 해결하기 위해서 하나의 마스크로 CMY를 동시에 사용하는 새로운 방법이 제안되었으며, CMY 점이 검은 점 대신에 밝은 영역에서 공간적으로 흩어서 출력된다. 그리고 어두운 영역의 그레이 값을 고려하기 위해서 톤 곡선 연결을 하였다. 기존의 방법에서 BNM(Blue Noise Mask)는 높은 낟알 특성(granularity)과 밝기값 범위가 좁은데 반하여, 제안한 방법은 낮은 낟알 특성과 넓은 밝기 범위와 높은 대비도를 가진다. 제안한 방법이 기존의 방법보다 공간적으로 다른 리치에 세 배에 해당하는 점을 사용하기 때문이다. 따라서 제안한 방법은 더 많은 공간적인 정보를 표현하고 기존의 BNM 방법과 비교하여 더욱 원 영상과 유사하게 표현할 수 있다.

• 한국분말재료학회지
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• 제31권3호
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• pp.226-235
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• 2024

InP quantum dots (QDs) have attracted researchers' interest due to their applicability in quantum dot light-emitting displays (QLED) or biomarkers for detecting cancers or viruses. The surface or interface control of InP QD core/ shell has substantially increased quantum efficiency, with a quantum yield of 100% reached by introducing HF to inhibit oxide generation. In this study, we focused on the control of bandgap energy of quantum dots by changing the Zn/(In+Zn) ratio in the In(Zn)P core. Zinc incorporation can change the photoluminescent light colors of green, yellow, orange, and red. Diluting a solution of as-synthesized QDs by more than 100 times did not show any quenching effects by the Förster resonance energy transfer phenomenon between neighboring QDs.

• 복식문화연구
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• 제16권5호
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• pp.863-877
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• 2008

The purpose of this study is to investigate the effect of dot pattern size(0.8, 1.8, 2.5, 5, 8), color combination (BG/R, Y/B), value tone(lt/dk, p/g), area-ratio on image information. Sets of stimulus and response scales(7 point semantic) were used as experimental materials. The stimuli were 20 color pictures manipulated with the combination of dot pattern size, color combination, value tone and area-ratio using computer simulation. The subjects were 240 female undergraduates living in Gyeongsangnam-do. Image factor of the stimulus was composed of 4 different components, visibility, chastity.feminity, cuteness and attractiveness. In the visibility, color combination, value tone, area-ratio, dot pattern size showed independent effect. In the chastity feminity, color combination, value tone, showed independent effect. In the cuteness, value tone, area-ratio, dot pattern size showed independent effect. Significant interaction effects of color and area-ratio combination on visibility and cuteness were found. Interaction efforts of color and value tone combination, value tone and area-ratio was significant on cuteness. For visibility image, BG/R combination of color and yellow background/blue dots were effective. For cuteness image, pale/grayish tone and background/dots area-ratio were effective.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2207-2211
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• 2011

Colloidal cadmium telluride (CdTe) quantum dots (QDs) and their nanoparticles have been synthesized by one pot sonochemical reactions under multibubble sonoluminescence (MBSL) conditions, which are quite mild and facile compared to other typical high temperature solution-based methods. For a typical reaction, $CdCl_2$ and tellurium powder with hexadecylamine and trioctylphosphine/trioctylphosphineoxide (TOP/TOPO) as a dispersant were sonicated in toluene solvent at 20 KHz and a power of 220W for 5-40 min at 60 $^{\circ}C$. The sizes of CdTe particles, in a very wide size range from 2 nm-30 ${\mu}m$, were controllable by varying the sonicating and thermal heating conditions. The prepared CdTe QDs show different colors from pale yellow to dark brown and corresponding photoluminescence properties due mainly to the quantum confinement effect. The CdTe nanoparticles of about 20 nm in average were found to have band gap of 1.53 eV, which is the most optimally matched band gap to solar spectrum.

• Advances in Energy Research
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• 제1권2호
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• pp.117-126
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• 2013

In this paper, core-shell semiconductor quantum dots (QDs) CdSeS/ZnS with emission at 490 nm and 450 nm were investigated for their use in luminescent down-shifting (LDS) layers. Luminescent quantum yield (LQY) of the QDs measurements in solution proposed that they were suitable candidates for inclusion in LDS layers. QDs were encapsulated in poly(methyl,methacrylate) (PMMA) polymer matrix and films were fabricated of $134{\pm}0.05$ microns. Selections of organic dyes from BASF Lumogen F range were also investigated for their use as LDS layers; Violet 570 and Yellow 083. The addition of LDS layers containing Violet 570 dye demonstrated a unity LQY when encapsulated within a PMMA matrix. A PV device of an LDS layer of Lumogen Violet 570 deposited on top of a crystalline silicon cell was fabricated where it was demonstrated to increase the efficiency of the cell by 34.5% relative.

• 한국발생생물학회지:발생과생식
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• 제15권4호
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• pp.325-329
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• 2011

본 연구는 수정란 이식에 의해 생산된 울릉칡소의 모색분포의 조사를 통해 울릉칡소의 모색 고정에 필요한 기초자료로 활용하고자 실시하였다. 1. 울릉칡소의 모색 분포는 황모 24.3%(67/276두), 흑모 13.0%(36/276두)와 호반모 62.7% (173/276두)의 분포를 보였으며, 입식우의 호반모 출현율이 66%(105/159두)로 관내이식에 의해 생산된 칡소의 호반모 비율 58.1%(68/117두)보다 다소 높은 경향이었다. 2. 성별에 따른 모색의 분포를 조사한 결과, 수컷의 경우 황모의 비율이 18.1%(25/138두)로 암컷의 31.4%(43/137두)에 비해 출현율이 낮은 반면, 호반모의 비율은 68.1%(94/138두)로 암컷의 56.9%(78/137두)에 비해 다소 높게 나타났다. 3. 비경의 흑반점의 강약에 따른 호반모의 발현 양상을 분석한 결과, 비경의 흑반점이 강할수록 호반모의 흑모 발현율이 높은 것으로 사료된다.