• 공업화학
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• 제23권2호
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• pp.138-142
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• 2012

블루 안료 15 : 6이라 불리는 ${\epsilon}$ 결정상의 동프탈로시아닌(${\epsilon}$-CuPc)는 LCD 패널에서 청색화소를 제공하는 중요한 소재로써, 본 연구에서는 ${\epsilon}$-CuPc 시료를 ${\epsilon}$-CuPc 나노 입자를 seed로 이용하는 방법으로 여러 조건에서 합성하여 적합한 용매 및 온도조건 등을 규명하였고, 이를 미리 합성한 ${\alpha}$ 및 ${\beta}$ 결정상의 CuPc 시료들과 비교함으로써 ${\epsilon}$-CuPc 시료의 결정상, 결정 순도, 합성 수율 및 미세구조를 상호 비교 분석하였다. 시료들의 화학 구조 및 결정 구조는 푸레어 변환 적외선(FT-IR) 분광기 및 X선 회절 분석기(XRD)를 이용하여 각각 비교 분석하였다. 또한, 입자의 형상 및 크기는 주사 전자현미경(FE-SEM)으로 비교 분석하였고, 열적 특성은 열중량분석기(TGA)를 이용하여 비교 분석하였다.

• Journal of Korean Neurosurgical Society
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• 제39권6호
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• pp.471-474
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• 2006

Objective : Neuroimaging data are of paramount importance in making correct diagnosis. We herein evaluate the clinical usefulness of image transfer using cellular phones to facilitate neurological diagnosis and decision-making. Methods : Selected images from CT, MRI scans, and plain films obtained from 50 neurosurgical patients were transferred by cellular phones. A cellular phone with a built-in 1,300,000-pixel digital camera was used to capture and send the images. A cellular phone with a 262,000 color thin-film transistor liquid crystal display was used to receive the images. Communication between both cellular phones was operated by the same wireless protocol and the same wireless internet service. We compared the concordance of diagnoses and treatment plans between a house staff who could review full-scale original films and a consultant who could only review transferred images. These finding were later analyzed by a third observer. Results : The mean time of complete transfer was $2{\sim}3\;minutes$. The quality of all images received was good enough to make precise diagnosis and to select treatment options. Transferred images were helpful in making correct diagnosis and decision making in 49/50 [98%] cases. Discordant result was caused in one patient by improper selection of images by the house staff. Conclusion : The cellular phone system was useful for image transfer and delivery patient's information, leading to earlier diagnosis and initiation of treatment. This usefulness was due to sufficient resolution of the built-in camera and the TFT-LCD, the user-friendly features of the devices, and their low cost.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2003년도 춘계학술발표회 초록집
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• pp.41-41
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• 2003

텅스텐(W)은 높은 thermal stability 와 process compatibility 및 우수한 corrosion r resistance 둥으로 integrated circuit (IC)의 gate 및 interconnection 둥으로의 활용이 대두되고 있으며, 차세대 thin film transistor liquid crystal display (TFT-LCD)의 gate 및 interconnection m materials 둥으로 사용되고 았다. 그러나, 이러한 장점을 가지고 있는 팅스텐 박막이 실제 공정상에 적용되가 위해서는 건식 식각이 주로 사용되는데, 이는 wet chemical 을 이용한 습식 식각을 사용할 경우 낮은 etch rate, line width 의 감소 및 postetch residue 잔류 동의 문제가 발생하기 때문이다. 또한 W interconnection etching 을 하기 위해서는 높은 텅스텐 박막의 etch rate 과 하부 layer ( (amorphous silicon 또는 poly-SD와의 높은 etch selectivity 가 필수적 이 라 할 수 있다. 그러 나, 지금까지 연구되어온 결과에 따르면 텅스탠과 하부 layer 와의 etch selectivity 는 2 이하로 매우 낮게 관찰되고 았으며, 텅스텐의 etch rate 또한 150nm/min 이하로 낮은 값을 나타내고 있다. 따라서 본 연구에서는 halogen-based inductively coupled plasma 를 이용하여 텅스텐 박막 식각시 여러 가지 첨가 가스에 따른 높은 텅스탠 박막의 etch rate 과 하부 layer 와의 높은 etch s selectivity 를 얻고자 하였으며, 그에 따른 식각 메커니즘에 대하여 알아보고자 하였다. $CF_4/Cl_2$ gas chemistry 에 첨 가 가스로 $N_2$와 Ar을 첨 가할 경 우 텅 스텐 박막과 하부 layer 간의 etch selectivity 증가는 관찰되지 않았으며, 반면에 첨가 가스로 $O_2$를 사용할 경우, $O_2$의 첨가량이 증가함에 따라 etch s selectivity 는 계속적으로 증가렴을 관찰할 수 있었다. 이는 $O_2$ 첨가에 따라 형성되는 WOF4 에 의한 텅스텐의 etch rates 의 감소에 비하여, $Si0_2$ 등의 형성에 의한 poly-Si etch rates 이 더욱 크게 감소하였기 때문으로 사료된다. W 과 poly-Si 의 식각 특성을 이해하기 위하여 X -ray photoelectron spectroscopy (XPS)를 사용하였으며, 식각 전후의 etch depth 를 측정하기 위하여 stylus p pmfilometeT 를 이용하였다.

• 한국컴퓨터정보학회논문지
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• 제24권11호
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• pp.71-78
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• 2019

현재 상용화된 대부분의 3D 디스플레이는 왼쪽 눈과 오른쪽 눈의 입력영상을 다르게 만들어 입체감을 만드는 양안시차 방식을 적용하고 있다. 하지만 상용화된 3D 영상 출력 장치는 성능 부족에 의한 시청자의 불편 유발과 시청위치의 제약 등의 문제들이 있다. 본 논문에서는 기존 Dual-cell 구조 대비 시야각, Crosstalk 감소, 광투과도를 향상할 수 있는 Single-cell 구조의 편광안경식 입체영상 시스템을 개발하고, 투과도 실험과 시야각 평가를 통해 Single-cell 구조의 편광안경식 입체영상 시스템 특성분석과 Dual-cell 구조 대비 성능향상 효과 분석을 진행하였다. 분석 결과 Single-cell 구조가 Dual-cell 구조 대비 투과도 부분에서 약 25% 이상의 높은 성능을 보이며, 시야각 평가 중 입체 영상 특성품질의 주요지표인 3D crosstalk 지표는 약 37% 이상 향상되는 것을 확인할 수 있었다.

• 한국산업보건학회지
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• 제31권4호
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• pp.342-352
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• 2021

Objectives: This study analyzed the local exposure levels of radiation emitted from the equipment with soft X-ray ionizers to investigate the radiation exposure levels in Liquid Crystal Display(LCD) manufacturing processes. Methods: This study measured the local radiation levels for the equipment installed in two LCD manufacturing companies. The equipment were installed at diverse processes and equipped with various number of ionizers. The local radiation levels were measured on the surface of the equipment by using direct reading equipment, and the measurements were converted into annual effective dose by considering the radiation exposure time of workers. Statistical analyses were performed to investigate the radiation exposure characteristics. Results: Annual effective doses for 97.6% of the equipment being measured were less than 1 mSv. However, the range of annual effective doses was 0.004 mSv ~ 2.167 mSv, which indicated a large variation among the equipment. Statistical analyses of the study found that this large variation was raised due to improper shielding of the equipment rather than process and/or equipment characteristics. To pinpoint the cause of this large variation in annual effective dose, this study improved the shielding of the equipment being radiated over 1 mSv and found that their average effective dose was reduced from 1.604 mSv to 0.126 mSv after shielding improvement. Conclusions: Relatively high exposure levels of radiation were observed in some equipment where their shielding were insufficiently thick and/or sealed. This finding implies that the shielding of the equipment is an important engineering countermeasure to control the radiation exposure levels in industries.

• Computers and Concrete
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• 제24권2호
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• pp.151-158
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• 2019

The sustainable development principle of replacing natural resources with renewable material is an important research topic. In this study, waste LCD (liquid crystal display) glass powder was used to replace cement (0%, 10%, 20% and 30%) through a volumetric method using three water-binder ratios (0.47, 0.59, and 0.71) to make cement mortar. The compressive strength was tested at the ages of 7, 28, 56 and 91 days. The test results show that the compressive strength increases with age but decreases as the water-binder ratio increases. The compressive strength slightly decreases with an increase in the replacement of LCD glass powder at a curing age of 7 days. However, at a curing age of 91 days, the compressive strength is slightly greater than that for the control group (glass powder is 0%). When the water-binder ratios are 0.47, 0.59 and 0.71, the compressive strength of the various replacements increases by 1.38-1.61 times, 1.56-1.80 times and 1.45-2.20 times, respectively, during the aging process from day 7 to day 91. Furthermore, a prediction model of the compressive strength of a cement mortar with waste LCD glass powder was deduced in this study. According to the comparison between the prediction analysis values and test results, the MAPE (mean absolute percentage error) values of the compressive strength are between 2.79% and 5.29%, and less than 10%. Thus, the analytical model established in this study has a good forecasting accuracy. Therefore, the proposed model can be used as a reliable tool for assessing the design strength of cement mortar from early age test results.

• Korean Chemical Engineering Research
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• 제59권2호
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• pp.165-173
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• 2021

눈부심 방지(Anti-glare, AG) 코팅 필름은 액정 디스플레이, LED 조명, 터치 패널 등 다양한 디스플레이 분야에 적용되고 있다. 본 연구에서는 UV 경화형 코팅 용액 내에 충전제로써 마이크로미터 크기의 실리카 입자를 첨가하여 눈부심 방지 효과를 부여하고자 하였다. 이 과정 중 실리카 입자의 크기, 함유량, 교반 시간, 다른 크기의 실리카 입자의 혼합 비율이 코팅 도막의 haze 값과 가시광선 투과도에 미치는 영향을 조사하였다. 그 결과 실리카 입자의 크기가 클수록, 또한 실리카 입자의 함유량이 증가할수록 haze 값은 증가하나, 가시광선 투과도는 감소하였다. 반면 교반 시간은 haze 값과 투과도에 큰 영향을 주지 못하였다. 또한 큰 크기의 실리카의 혼합 비율이 증가할수록 haze 값은 증가하나, 이와 반대로 가시광선 투과도는 감소하는 것을 확인할 수 있었다.

• The Journal of Advanced Prosthodontics
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• 제14권6호
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• pp.379-387
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• 2022

PURPOSE. The aim of this study is to compare the casts obtained by using conventional techniques and liquid crystal display (LCD) three-dimensional (3D) print techniques in the All-on-4 treatment concept of the edentulous mandibular jaw. MATERIALS AND METHODS. In this study, a completely edentulous mandibular acrylic cast (typodont) with bone-level implants placed with the Allon-4 technique served as a reference cast. In this typodont, impressions were taken with the conventional technique and dental stone casts were obtained. In addition, after scanning the acrylic cast in a dental laboratory scanner and obtaining the Standard Tessellation Language (STL) data, 3D printed casts were manufactured with a 3D printing device based on the design. The stone and 3D printed casts were scanned in the laboratory scanner and STL data were obtained, and then the interimplant distances were measured using Geomagic Control X v2020 (3D Systems, Rock Hill, SC, USA) analysis software (n = 60). The obtained data were statistically evaluated with one-way analysis of variance (ANOVA) and Tukey's pairwise comparison tests. RESULTS. As a result of the one-way ANOVA test, it was determined that the stone casts, 3D printed casts, and reference cast values in all distance intervals conformed to the normal distribution and these values had a significant difference among them in all distance intervals. In Tukey pairwise comparison test, significant differences were found between casts at all distance intervals. In all analyses, the level of significance was determined as .05. CONCLUSION. 3D printed casts obtained with a 3D LCD printing device can be an alternative to stone casts when implants are placed in edentulous jaws. [J Adv Prosthodont 2022;14:379-87]

• 한국산업융합학회 논문집
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• 제26권4_2호
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• pp.629-637
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• 2023

This study aimed to evaluate the effect of post-curing equipment and time on the flexural strength of 3D printing resins produced by a liquid crystal display(LCD) printer. The three 3D printing resins(DENTCA Denture Teeth, DT; C&B 5.0 hybrid, CH; C&B Permanent A2, CP) were divided into four groups according to post-curing time(10 min and 30 min) and equipment with or without vacuum treatment. For the three-point flexural strength test and biaxial strength test were prepared by method according to ISO 10477, ISO 6872, respectively. Flexural strength was measured with universal testing machine. Comparison between post-curing time of each post-curing equipment was analyzed by independent sample t-test and Mann-Whitney U test(α=.05), and comparison between groups according to each 3D printing resin was performed by Kruskal-Wallis test and post-hoc by Bonferroni-Dunn test(α=.05). The flexural strength of the resin post-curing under vacuum was higher than that of the resin post-curing in air. In the comparison according to the post-curing time, in the case of the post-curing equipment without vacuum, the 30 minute curing time showed significantly higher flexural strength than the 10 minute curing time, except for the biaxial flexural strength of CH(P<.05). In the post-curing equipment with vacuum, the three-point flexural strength of all 3D printing resins(DT, CH, and CP) showed a higher value at 30 minute curing time than at 10 minute curing time.

• 청정기술
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• 제15권4호
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• pp.253-257
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• 2009

LCD 제조공정에서 배출되는 질산과 초산, 인산, 그리고 Al과 같은 금속이온을 함유한 폐에칭액으로부터 진공증발과 확산투석을 이용하여 고순도 인산을 회수하여 인산암모늄을 제조하고자 하였다. 진공증발을 이용하여 질산과 초산을 제거하였다. 진공도가 -650 mmHg인 경우에는 온도 413 K 이상에서 완전 분리되었고, 진공도가 -700 mmHg인 경우에는 온도 393 K 이상의 영역에서 완전히 분리되었다. 그리고 진공도 -730 mmHg의 경우는 온도 383 K 이상에서도 완전 분리가 가능하였다. 99%의 질산과 초산을 제거하였으며, 확산투석을 이용하여 약 97.5% 이상의 Al을 제거하였다. 이렇게 얻어진 고순도 인산과 수산화암모늄을 이용하여 일인산암모늄을 제조하는 공정에서 급격한 발열반응을 제어하고 안정된 적정조건을 도출하기 위하여 수산화암모늄의 농도, 적정 몰비, pH, 온도 등의 반응인자를 조절하여 회수율 약 90%의 일인산암모늄을 제조하였다.