• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1250-1253
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• 1994

(100), (110) and (111) Si wafers are etched by isotropic etching method, anisotropic etching method using KOH etchant and EPW etchant and combined two-step etching method to compare the results. Isotopic etching method is effective in fabrication of wedge-shaped tips, especially (110) Si. Anisotropic etching method of (100) Si using EPW etchant can fabricate sharp cone-shaped tips and isotropic etching after anisotropic etching of (100) Si can fabricate wedge-shaped tips.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.937-939
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• 2009

In this paper, we report electrical properties of OTFTs made by ink-jet printing with polyvinylphenol (PVP) for bank layer and bis(triisopropylsilylenthynyl) pentacene (TIPS-pentacene) for semiconductor. We could achieve better crystallization and surface uniformity of TIPS pentacene by employing PVP bank layer. The OTFT with PVP bank layer exhibited an field-effect mobility of 0.18 $cm^2$/Vs, current on/off ratio of $2.09{\times}10^5$, and subthreshold slope of 0.42 V/decane.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.386-391
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• 2002

Stainless rolling stocks are usually fabricated by spot welding process without painting. Indentation on the surface of the car body after spot welding injures the beauty of the stainless rolling stocks. In this study, electrode tips to reduce the indentation are developed and applied to the actual spot welding works. The developed tips are composed of head, nut hole far cooling water, body and resistance material. They provide large surface contact area with the base materials during spot welding and enhance the current density by necking. Experimental results using the developed tips show that small indentation and sufficient tensile shear strength is produced due to large contact area and enhanced current density.

• 디지털콘텐츠
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• 11호통권66호
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• pp.42-46
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• 1998

국내 데이터베이스의 활용을 촉진하고 데이터베이스 업체의 개발의욕을 고취하기 위하여 한국데이터베이스진흥센터가 제정하고 정보통신부가 후원하는 데이터베이스 대상의 9월 우수 데이터베이스 수상작으로 한국신용정보의 'NICE-TIPS'가 선정되었다.

• Korean Chemical Engineering Research
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• 제54권1호
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• pp.57-63
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• 2016

Polyvinylidene fluoride (PVDF) 평막 제조를 위하여 PVDF의 용매와 희석제로서 n-methyl-2-pyrrolidone (NMP)와 dibutyl-phthlate (DBP)를 각각 사용하여 열유도 상분리(thermally induced phase separation, TIPS)와 비용매유도 상분리(nonsolvent induced phase separation, NIPS)를 동시에 유도하였다. NMP와 DBP를 PVDF와 용융 혼합할 경우 TIPS 공정에서의 결정화 온도가 낮아졌고 NIPS 공정에서의 불안정 영역이 확대되었다. 용매와 희석제의 비율에 따라 상분리 메카니즘이 변화하였고 이에 따라 다양한 구조의 막이 형성됨을 확인하였다. 또한 dope 용액과 비용매의 접촉여부에 따라 지배적인 상분리 거동이 결정되었다. 열전달이 물질전달에 비하여 빠르게 이루어지므로 막의 표면은 NIPS에 의하여 지배를 받고 막의 내부는 TIPS에 의한 구조가 형성되었다. 또한 dope 용액의 급냉온도에 따라 상분리 메카니즘 및 상분리 속도가 변화하여 다양한 구조를 형성하였다.

• 한국자원식물학회지
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• 제32권6호
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• pp.689-697
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• 2019

This study describes an efficient and widely applicable droplet-vitrification following cryopreservation for shoot tips of strawberry (Fragaria × ananassa Duch.) cvs. 'Wonkyo3114' and 'Gurumi40'. The shoot tips were precultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3-0.5M). Precultured explants were osmoprotected with loading solution (LS, C4) containing 20% glycerol and 20% sucrose for 40 min and exposed to dehydration solution (B5) containing 40% glycerol and 40% sucrose for 40 min at 25℃, Subsequently, the explants were transferred onto droplets containing 2.5 μL PVS3 on sterilized aluminum foils (4 cm × 0.5 cm) prior to direct immersion in liquid nitrogen (LN) for 1 h. The highest regrowth rate (%) in both the cultivars was obtained when the shoot tips were precultured with MS + 0.3M sucrose for 40 h at 25℃. The cryopreserved shoots tips exhibited 55% regrowth rate by culturing in NH₄NO₃-free MS medium supplemented with 3% sucrose, 1.0 g/L casein, 1.0 mg/L GA₃, and 0.5 mg/L BA for 5 weeks and in MS medium supplemented with 0.5 mg/L GA₃ for 8 weeks. This result shows that droplet-vitrification could be employed as a promising method for cryostorage of strawberry germplasm.

• 한국자원식물학회지
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• 제29권6호
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• pp.635-641
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• 2016

Sweet potato (Ipomoea batatas L.) shoot tips grown in vitro were successfully cryopreserved by encapsulation-vitrification. Encapsulated explants are very easily manipulated, due to the relatively large size of the alginate beads, and a large number of samples can be treated simultaneously. In this study, the effects of sucrose preculture, cryoprotectant preculture, and post-warm recovery media on regrowth, following liquid nitrogen (LN) exposure, were investigated to establish an efficient encapsulation-vitrification protocol for sweet potato. Shoot tips of plants grown in vitro were precultured in 0.3 M sucrose for 2 d before encapsulation. Encapsulated shoot tips were pre-incubated in liquid MS (Murashige and Skoog) medium containing 0.5 M sucrose for 16 h, before preculturing in sucrose-enriched medium (0.7 M sucrose) for 8 h. Shoot tips were osmoprotected with 35% plant vitrification solution 3 (PVS3) for 3 h, before being dehydrated with PVS3 for 2 h at $25^{\circ}C$. The encapsulated and dehydrated shoot tips were transferred to 2 mL cryotubes, suspended in 0.5 mL PVS3, and plunged directly into liquid N. High levels of shoot formation were obtained for the cv. Yeulmi (65.7%) and Yeonwhangmi (80.3%). The regrowth rates of cryopreserved samples in Yeulmi (78.9%) and Yeonwhangmi (91.3%), following culture on ammonium-free MS medium for 5 d, were much higher than those cultured on standard MS medium (65.7% and 80.3%, respectively). This encapsulation-vitrification is a promising method for the long-term preservation of sweet potato.

• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.14.1-14.7
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• 2020

Objective: The aim of this study was to perform a comparative evaluation of the effectiveness of ultrasonic tips versus the Terauchi file retrieval kit (TFRK) for the removal of broken endodontic instruments. Materials and Methods: A total of 80 extracted human first mandibular molars with moderate root canal curvature were selected. Following access cavity preparation canal patency was established with a size 10/15 K-file in the mesiobuccal canals of all teeth. The teeth were divided into 2 groups of 40 teeth each: the P group (ProUltra tips) and the T group (TFRK). Each group was further subdivided into 2 smaller groups of 20 teeth each according to whether ProTaper F1 rotary instruments were fractured in either the coronal third (C constituting the PC and TC groups) or the middle third (M constituting the PM and TM groups). Instrument retrieval was performed using either ProUltra tips or the TFRK. Results: The overall success rate at removing the separated instrument was 90% in group P and 95% in group T (p > 0.05) The mean time for instrument removal was higher with the ultrasonic tips than with the TFRK (p > 0.05). Conclusion: Both systems are acceptable clinical tools for instrument retrieval but the loop device in the TFRK requires slightly more dexterity than is needed for the ProUltra tips.

• Gut and Liver
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• 제12권6호
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• pp.704-713
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• 2018

Background/Aims: Gastric varices (GVs) are a major cause of upper gastrointestinal bleeding in patients with liver cirrhosis. The current treatments of choice are balloon-occluded retrograde transvenous obliteration (BRTO) and the placement of a transjugular intrahepatic portosystemic shunt (TIPS). We aimed to compare the efficacy and outcomes of these two methods for the management of GV bleeding. Methods: This retrospective study included consecutive patients who received BRTO (n=157) or TIPS (n=19) to control GV bleeding from January 2005 to December 2014 at a single tertiary hospital in Korea. The overall survival (OS), immediate bleeding control rate, rebleeding rate and complication rate were compared between patients in the BRTO and TIPS groups. Results: Patients in the BRTO group showed higher immediate bleeding control rates (p=0.059, odds ratio [OR]=4.72) and lower cumulative rebleeding rates (logrank p=0.060) than those in the TIPS group, although the difference failed to reach statistical significance. There were no significant differences in the rates of complications, including pleural effusion, aggravation of esophageal varices, portal hypertensive gastropathy, and portosystemic encephalopathy, although the rate of the progression of ascites was significantly higher in the BRTO group (p=0.02, OR=7.93). After adjusting for several confounding factors using a multivariate Cox analysis, the BRTO group had a significantly longer OS (adjusted hazard ratio [aHR]=0.44, p=0.01) and a longer rebleeding-free survival (aHR=0.34, p=0.001) than the TIPS group. Conclusions: BRTO provides better bleeding control, rebleeding-free survival, and OS than TIPS for patients with GV bleeding.

• 멤브레인
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• 제28권6호
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• pp.395-405
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• 2018

본 연구에서 Poly(ethylene-co-vinylalcohol) EVOH 중공사막은 열유도상분리(TIPS)법을 이용하여 제조하였다. 다양한 조건에서 제조된 모든 분리막에서 액-액 상분리에 의해 기공이 서로 연결되어 있는 스폰지 구조가 관찰되었다. 글리세롤과 PEG200은 TIPS 방법에서 희석제로 사용하였고, 냉각조에 글리세롤을 혼합한 냉매를 사용하여 중공사 외표면의 기공을 조절하였다. 또한 혼합냉매의 온도를 높여 큰 기공의 형성을 유도하였다. 본 연구에서는 고분자의 농도, 희석제, 냉각조의 영향에 따른 분리막의 구조, 투과도, 기계적 강도에 대해 실험을 통해 알아보고 상호관계에 대해 심도 있게 연구하였다.