High ft 30nm Triple-Gate In0.7GaAs HEMTs with Damage-Free SiO₂/SiNx Sidewall Process and BCB Planarization

Dae-Hyun Kim,Seong-Jin Yeon,Saegn-SUb Song,Jae-Hak Lee,Kwang-Seok Seo 대한전자공학회 2004 Journal of semiconductor technology and science Vol.4 No.2

A 30 nm In0.7GaAs High Electron Mobility Transistor (HEMT) with triple-gate has been successfully fabricated using the SiO₂/SiN, sidewall process and BCB planarization. The sidewall gate process was used to obtain finer lines, and the width of the initial line could be lessened to half by this process. To till the Schottky metal effectively to a narrow gate line after applying the developed sidewall process, the sputtered tungsten (W) metal was utilized instead of conventional e-beam evaporated metal. To reduce the parasitic capacitance through dielectric layers and the gate metal resistance (Rg), the etchedback BCB with a low dielectric constant was used as the supporting layer of a wide gate head, which also offered extremely low Rg of 1.7 Ohm for a total gate width (Wg) of 2X100 m. The fabricated 30nm In0.7GaAs HEMTs showed Vth of -0.4V, Gm,max, of 1.7S/mm, and f.r of 421GHz. These results indicate that InGaAs nano-HEMT with excellent device performance could be successfully fabricated through a reproducible and damage-free sidewall process without the aid of state-of-the-art lithography equipment. We also believe that the developed process will be directly applicable to the fabrication of deep sub-50nm InGaAs HEMTs if the initial line length can be reduced to below 50nm order.<br/> <br/>

學校長의 變革的 指導性과 敎師의 職務滿足度의 關係

Kwak Dae Sub(郭大燮) 공주대학교 교육연구소 1998 교육연구 Vol.14 No.-

This study was started for the purpose of identifying the relationship between principals’ transformational leadership and teachers’ job-satisfaction in primary schools. As a result, it was found that the higher the level of transformational leadership of principals, the stronger the teachers’ job-satisfaction, and that the ‘human respect’ factor of the three sub-factors of transformational leadership was the most predictable one to the level of teachers’ job-satisfaction.

Conjoined Audio Fingerprint based on Interhash and Intra hash Algorithms

Kim, Dae-Jin,Choi, Hong-Sub The Korea Contents Association 2015 International Journal of Contents Vol.11 No.4

In practice, the most important performance parameters for music information retrieval (MIR) service are robustness of fingerprint in real noise environments and recognition accuracy when the obtained query clips are matched with the an entry in the database. To satisfy these conditions, we proposed a conjoined fingerprint algorithm for use in massive MIR service. The conjoined fingerprint scheme uses interhash and intrahash algorithms to produce a robust fingerprint scheme in real noise environments. Because the interhash and intrahash algorithms are masked in the predominant pitch estimation, a compact fingerprint can be produced through their relationship. Experimental performance comparison results showed that our algorithms were superior to existing algorithms, i.e., the sub-mask and Philips algorithms, in real noise environments.

High $f_T$ 30nm Triple-Gate $In_{0.7}GaAs$ HEMTs with Damage-Free $SiO_2/SiN_x$ Sidewall Process and BCB Planarization

Kim, Dae-Hyun,Yeon, Seong-Jin,Song, Saegn-Sub,Lee, Jae-Hak,Seo, Kwang-Seok The Institute of Electronics and Information Engin 2004 Journal of semiconductor technology and science Vol.4 No.2

A 30 nm $In_{0.7}GaAs$ High Electron Mobility Transistor (HEMT) with triple-gate has been successfully fabricated using the $SiO_2/SiN_x$ sidewall process and BCB planarization. The sidewall gate process was used to obtain finer lines, and the width of the initial line could be lessened to half by this process. To fill the Schottky metal effectively to a narrow gate line after applying the developed sidewall process, the sputtered tungsten (W) metal was utilized instead of conventional e-beam evaporated metal. To reduce the parasitic capacitance through dielectric layers and the gate metal resistance ($R_g$), the etchedback BCB with a low dielectric constant was used as the supporting layer of a wide gate head, which also offered extremely low Rg of 1.7 Ohm for a total gate width ($W_g$) of 2x100m. The fabricated 30nm $In_{0.7}GaAs$ HEMTs showed $V_{th}$of -0.4V, $G_{m,max}$ of 1.7S/mm, and $f_T$ of 421GHz. These results indicate that InGaAs nano-HEMT with excellent device performance could be successfully fabricated through a reproducible and damage-free sidewall process without the aid of state-of-the-art lithography equipment. We also believe that the developed process will be directly applicable to the fabrication of deep sub-50nm InGaAs HEMTs if the initial line length can be reduced to below 50nm order.

Inkjet‐Printable Nanoporous Ag Disk Arrays Enabling Coffee‐Ring Effect‐Driven Analyte Enrichment Towards Practical SERS Applications

Jung-Sub Wi,Jeong Dae Kim,Wonseok Lee,Hyunsik Choi,Minjeong Kwak,Jungkeun Song,Tae Geol Lee,Jong G. Ok 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.2

To make surface enhanced Raman scattering (SERS) sensors more practical, we propose nanoporous Ag disks as SERSactive plasmonic structures that can be readily inkjet-printed just before use to avoid degradation of SERS enhancement. Together with the aid of the enhanced plasmonic fi elds from the nanoporous Ag (confirmed by electromagnetic simulation), we utilize a coffee-ring effect to concentrate target analytes, which is demonstrated by confocal Raman measurements. By using the proposed SERS sensor, Raman signals of TiO 2 nanoparticles with a concentration of ppm to sub-ppb have been successfully measured. TiO 2 in commercial consumables has been also detected by distinguishing its crystalline phase.

Sodium butyrate has context-dependent actions on dipeptidyl peptidase-4 and other metabolic parameters

Lee, Eun-Sol,Lee, Dong-Sung,Pandeya, Prakash Raj,Kim, Youn-Chul,Kang, Dae-Gil,Lee, Ho-Sub,Oh, Byung-Chul,Lee, Dae Ho The Korean Society of Pharmacology 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.5

Sodium butyrate (SB) has various metabolic actions. However, its effect on dipeptidyl peptidase 4 (DPP-4) needs to be studied further. We aimed to evaluate the metabolic actions of SB, considering its physiologically relevant concentration. We evaluated the effect of SB on regulation of DPP-4 and its other metabolic actions, both in vitro (HepG2 cells and mouse mesangial cells) and in vivo (high fat diet [HFD]-induced obese mice). Ten-week HFD-induced obese C57BL/6J mice were subjected to SB treatment by adding SB to HFD which was maintained for an additional 16 weeks. In HepG2 cells, SB suppressed DPP-4 activity and expression at sub-molar concentrations, whereas it increased DPP-4 activity at a concentration of $1,000{\mu}M$. In HFD-induced obese mice, SB decreased blood glucose, serum levels of insulin and $IL-1{\beta}$, and DPP-4 activity, and suppressed the increase in body weight. On the contrary, various tissues including liver, kidney, and peripheral blood cells showed variable responses of DPP-4 to SB. Especially in the kidney, although DPP-4 activity was decreased by SB in HFD-induced obese mice, it caused an increase in mRNA expression of $TNF-{\alpha}$, IL-6, and $IL-1{\beta}$. The pro-inflammatory actions of SB in the kidney of HFD-induced obese mice were recapitulated by cultured mesangial cell experiments, in which SB stimulated the secretion of several cytokines from cells. Our results showed that SB has differential actions according to its treatment dose and the type of cells and tissues. Thus, further studies are required to evaluate its therapeutic relevance in metabolic diseases including diabetes and obesity.

[논문]스트렷-타이 모델에 의한 사각형 단면 코벨의 설계 기법

김대성,김태완,이승훈,엄장섭,진치섭 釜山大學校生産技術硏究所 2004 生産技術硏究所論文集 Vol.63 No.-

콘크리트 코벨은 D-영역을 갖는 대표적인 구조물로서 복잡하고 다양한 형상의 파괴메커니즘을 보인다. 이는 응력집중과 기하학적인 불연속으로 일반적인 보 이론의 적용이 불가능하여 해석 및 설계에 어려움이 많다. 본 연구에서는 지압파괴,압축파괴 및 전단파괴를 유발하는 복잡한 파괴메커니즘을 형성하고 있는 사각형 단면 코벨의 거동 및 파괴형상을 예측하고 스트릿-타이 모텔을 적용하여 해석 및 설계를 하였다. 또한 현행의 설계방법과의 비교를 통하여 스트렷-타이 모델이 보다 합리적이고 경제적인 설계방법임을 보였다.

RT-LAMP를 이용한 콩황화일반모자이크바이러스의 진단

배대현, 이영훈, 김봉섭, 윤영남, 강범규, 최만수, 구성철, 김현태, 윤홍태, 이수헌, 백인열 忠北大學校 農業科學硏究所 2014 農業科學硏究 Vol.30 No.2

Soybean yellow common mosaic virus (SYCMV) has been recently reported, it has been occurred a lot with Soybean mosaic virus (SMV) and Soybean yellow mottle mosaic virus (SYMMV) in soybean field. SYCMV belongs to genus of Sobemovirus and induced viral symptoms with yellowing, mottle and mosaic. A reverse transcription loop-mediated isothermal amplification (RT-LAMP) method allowed one-step detection of gene amplification by simple procedure and needed only a simple incubator for isothermal template. This RT-LAMP method allowed direct detection of RNA from virus-infected plants without thermal cycling and gel electrophoresis. In this study, we designed RT-LAMP primers named SYCML-F3/B3/FIP/BIP from coat protein gene sequence of SYCMV. After the reaction of RTLAMP, products were identified by electrophoresis and with the detective fluorescent dye, SYBR Green I. under daylight and UV light. Optimal reaction condition was at 63 for 60min and the primers of RTLAMP showed the specificity for only SYCMV tested in this study.

항진균성 항생물질을 생산하는 Streptoverticillium sp. NA-4083의 분리 및 동정

임대석,윤상균,이명섭,윤원호,김창한 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.6

전국 각지의 토양에서 441균주의 방선균을 분리한 결과 Trichophyton mentagrophytes, Trichophyton rubrum, Nanniza otae 및 Pyricularia oryzae 등의 진균에 광범위한 항진균활성을 나타내는 방선균 NA-4803을 선발하여 그 균주의 동정을 실시하였다. 분리균주 NA-4803은 Gram 양성세균 4균주, Gram 음성세균 2균주, 효모 2균주, 곰팡이 5균주, 조류 1균주에 대해 약한 항균활성을 보이는 반면, 곰팡이 Trichophyton mentagrophytes, Trichophyton rubrum, Nanniza otae 및 Pyricularia oryzae에 대해서는 비교적 강한 항진균활성을 나타내었다. 분리균주 NA-4803은 생리적 특성, 항균활성, lectithinase 및 lipolytic 활성, 각종 유기물의 분해력, 항생물질에 대한 저항성, 온도, pH 및 화학저해제의 첨가에 따른 생육, 질소원의 이용성 및 탄소원의 이용성 등에 있어서 cluster group F에 속하며 Cluster No. 58에 해당하는 Streptoverticillium blastmyceticum과 가장 유사하게 비교·동정되었으나 nitrate 환원성의 양성반응, L-tyrosine 분해력의 음성반응 및 cephaloridine에 대한 저항성에 음성반응을 보였고, 탄소원 중 L-rhamnose와 inulin을 이용하는 것으로 보아 Streptoverticillium blastmyceticum과 다른 특성을 나타내었다. 따라서 분리균주 NA-4803은 Streptoverticillium sp. NA-4803으로 동정되었다. The aim of the present research program was to develop a strain of actinomycetes producing antifungal substance. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying selective agar for actinomycetes. Among over 440 isolates, a strain (NA-4803) producing antifungal substance against Trichophyton spp. Nannizzia otae and Pyricularia oryzae was selected. The strain NA-4803 was identified as strain similar to Streptoverticillium blastmyceticum with respect to morphological and physiological characteristics, lecithinase and lipolytic activity, degradation of organic compounds, resistance to antibiotics and utilization of carbon and nitrogen sources. But it showed some differences such as positive reaction of nitrate reduction, negative reaction of L-tyrosine degradation, resistance to cephaloridine, and utilization of I rhamnose and inulin. The strain NA-4803 was named as Streptoverticillium sp. NA-4803.

科學 學習過程에서 學生의 基本槪念 理解의 實態에 關한 硏究 : C. M. I. 方法으로

吳岱燮,呂煥鎭 경북대학교 과학교육연구소 1980 科學敎育硏究誌 Vol.4 No.-

We studied a student's understanding of basic scientific concepts in learning process of middle school. Based on the result of Test, We made and U-P table and a M-P table by computer. It shows that which concepts are learning by each student. By this evidence, We proposed the reforming plans for teaching-learning method. We can conculede that there are many kinds of patterns in learning process of basic scientific concepts.