• Title/Summary/Keyword: ISL

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The Modeling of ISL(Intergrated Schottky Logic) Characteristics by Computer Simulations (컴퓨터 시뮬레이션에 의한 ISL 특성의 모델링)

  • 김태석
    • Journal of Korea Multimedia Society
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    • v.3 no.5
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    • pp.535-541
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    • 2000
  • In this paper, we analyzed the characteristics of schottky junction to develop the voltage swing of ISL, and simulated the characteristics with the programs at this junctions. Simulation programs for analytic characteristics are the SUPREM V, SPICE, Medichi, Matlab. The schottky junction is rectifier contact between platinum silicide and silicon, the characteristics with programs has simulated the same conditions. The analytic parameters were the turn-on voltage, saturation current, ideality factor in forward bias, and has shown the results of breakdown voltage between actual characteristics and simulation characteristics in reverse bias. As a result, th forward turn-on voltage, reverse breakdown voltage, barrier height were decreased but saturation current and ideality factor were increased by substrates increased concentration variations.

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Glycyrrhiza uralensis (licorice) extracts increase cell proliferation and bone marker enzyme alkaline phosphatase activity in osteoblastic MC3T3-E1 cells

  • Cho, Young-Eun;Kwun, In-Sook
    • Journal of Nutrition and Health
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    • v.51 no.4
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    • pp.316-322
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    • 2018
  • Purpose: The Glycyrrhiza uralensis species (Leguminosae) as a medicinal biocompound, and one of its root components, isoliquritigenin (ISL), which is a flavonoid, has been reported to have anti-tumor activity in vitro and in vivo. However, its function in bone formation has not been studied yet. In this study, we tested the effect of Glycyrrhiza uralensis (ErLR) and baked Glycyrrhiza uralensis (EdLR) extracts on osteoblast proliferation, alkaline phosphatase (ALP) activity, and bone-related gene expression in osteoblastic MC3T3-E1 cells. Methods: MC3T3-E1 cells were cultured in various levels of ErLR (0, 5, 10, 15, $20{\mu}g/mL$), EdLR (0, 5, 10, 15, $20{\mu}g/mL$), or ISL (0, 5, 10, 15, $20{\mu}M$) in time sequences (1, 5, and 20 days). Also, isoliquritigenin (ISL) was tested for comparison to those two biocompound extracts. Results: MTT assay results showed that all three compounds (ErLR, EdLR, and ISL) increased osteoblastic-cell proliferation in a concentration-dependent manner for one day. In addition, both ErLR and EdLR compounds elevated the osteoblast proliferation for 5 or 20 days. Extracellular ALP activity was also increased as ErLR, EdLR, and ISL concentration increased at 20 days, which implies the positive effect of Glycyrrhiza species on osteoblast mineralization. The bone-related marker mRNAs were upregulated in the ErLR-treated osteoblastic MC3T3-E1 cells for 20 days. Bone-specific transcription factor Runx2 gene expression was also elevated in the ErLR- and EdLR-treated osteoblastic MC3T3-E1 cells for 20 days. Conclusion: These results demonstrated that Glycyrrhiza uralensis extracts may be useful for preventing osteoporosis by increasing cell proliferation, ALP activity, and bone-marker gene expression in osteoblastic cells.

Numerical Study of Normal Start and Unstart Processes In a Superdetonative Speed Ram Accelerator (초폭굉속도 램가속기의 정상발진과 불발과정에 대한 수치해석)

  • Moon, Guee-Won;Jeung, In-Seuck;Choi, Jeong-Yeol;Seiler, Friedrich;Patz, Gunther;Smeets, Gunter;Srulijes, Julio
    • 한국연소학회:학술대회논문집
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    • 2002.06a
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    • pp.123-132
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    • 2002
  • A numerical study was conducted to investigate the combustion phenomena of normal start and unstart processes based on ISL's RAMAC 30 experiments with different diluent amounts and fill pressures in a ram accelerator. The initial projectile launching speed was 1.8 km/s which corresponded to the superdetonative speed of the stoichiometric $H_2/O_2$ mixture diluted with 5 $CO_2$ or 4 $CO_2$. Experiments with same condition except for projectile surface material demonstrated that ignition was successful with an aluminum projectile, but no combustion was observed in case of a steel projectile. In this study, it was found that neither shock nor viscous heating was sufficient to ignite the mixture at a low speed of 1.8 km/s, as was found in the experiments using a steel projectile. However, we could succeed in igniting the mixtures by imposing a minimal amount of additional heat to the combustor section and simulate the normal start and unstart processes found in the experiments with an aluminum projectile. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations coupled with a Baldwin-Lomax turbulence model and detailed chemistry reaction equations of $H_2/O_2/CO_2$ suitable for high-pressure gaseous combustion were considered. The governing equations were discretized by a high order accurate upwind scheme and solved in a fully coupled manner with a fully implicit, time accurate integration method. The numerical results matched almost exactly to the experimental results. As a result, it was found that the normal start and unstart processes depended on the strength of gas mixture, development of shock-induced combustion wave stabilized by the first separation bubble, and its size and location.

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Orbit Determination of Korea Regional Navigation Satellite System Using Inter-Satellite Links and Ground Observations

  • Choi, Jungmin;Oh, Hyungjik;Park, Chandeok;Park, Sang-Young
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.2
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    • pp.327-333
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    • 2017
  • This study presents the orbit determination (OD) of a candidate Korea Regional Navigation Satellite System (KRNSS) using both inter-satellite links (ISLs) and ground observations. The candidate constellation of KRNSS is first introduced. The OD algorithm based on both ISL and ground observation is developed, and consists of three main components: dynamic model for Korean navigation satellites, measurement model for ISLs and ground observations, and the batch least-square filter for estimating OD parameters. As numerical simulations are performed to analyze the OD performances, the present study focuses on investigating the effects of ISL measurements on the OD accuracy of KRNSS. Simulation results show that the use of ISLs can considerably enhance the OD accuracy to one meter (design preference) under certain distributions of ground stations.

A Numerical Study on Flame Stability with Extended Combustor in Superdetonative Mode Ram Accelerator (초폭굉 모드 램 가속기의 연소실 길이에 따른 화염유지특성에 대한 수치적 연구)

  • Sung, Kun-Min;Jeung, In-Seuck
    • 한국연소학회:학술대회논문집
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    • 2007.05a
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    • pp.126-129
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    • 2007
  • An numerical study was conducted on superdetonative mode ram accelerator with extended combustor. The computation case was based on ISL's RAMAC30 II experiment. For 50% length increased combustor, flame is not sustained. For the case of 60% and 70% increase, flame is successfully sustaind. But detonation wave is oscillating and acceleration is fluctuating. Increasing of combustor length is helpful for sustaing detonation wave but it may cause unstart.

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2마이크론의 설계치수를 갖는 ISL설계 및 제작

  • Lee, Yong-Jae;Lee, Jin-Hyo
    • ETRI Journal
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    • v.8 no.3
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    • pp.15-23
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    • 1986
  • ISL(Integrated Schottky Logic)의 고집적화를 위하여 종래의 p-n 접합 격리 방법 대신에 산화막으로 격리시킨 2마이크론의 최소 설계치수를 갖는 소자를 설계, 제작하여 특성을 분석하였다. 접합 형성을 위한 불순물은 이온 주입법을 이용하여 고속소자가 필연적으로 갖추어야 하는 얕은 접합으로 형성을 시켰으며, 출력단의 쇼트키 다이오드는 백금 실리 사이드를 이용하였다. 링 발진기의 특성에서 최소 전달지연 시간은 한 게이트당 5.7ns의 속도 특성과 논리 진폭은 360mV의 현격한 특성을 나타내었다 .

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Distribution and Northernmost Limit on the Korean Peninsula of Three Evergreen Trees (상록활엽수 3종의 한반도분포 및 자생북한계지)

  • Lee, Jung-Hyun;Choi, Byoung-Hee
    • Korean Journal of Plant Taxonomy
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    • v.40 no.4
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    • pp.267-273
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    • 2010
  • The distribution of three typical warm-temperate evergreen trees, Quercus acuta Thunb., Neolitsea sericea (Blume) Koidz., and Machilus thunbergii Siebold & Zucc., were surveyed on the Korean Peninsula based on field and specimen investigations and the distribution maps of the three species were prepared. The distribution patterns of the species correspond to the south coast floristic region in Korea, which includes the distributional areas of Jeju-do, Isl. Ulleung, the southern coastal areas, and the areas up to the islands around Incheon in the Yellow Sea. The northernmost limit of the distribution of Quercus acuta is Isl. Nap of Incheon in the west, and a new distribution was found at Isl. Ulleung in the East Sea; additionally, the limit of Neolitsea sericea is the Deojoek archipelago of Incheon. The northernmost limit of Machilus thunbergii is Isl. Daecheong of Incheon, which is the highest latitude among those of the three species. This distribution survey of evergreen broad-leaved trees in Korea can be used as basic data for the delimitation of floristic regions and as a bio-indicator of climatic change.

Comparative Analysis of Filtering Techniques for Vegetation Points Removal from Photogrammetric Point Clouds at the Stream Levee (하천 제방의 영상 점군에서 식생 점 제거 필터링 기법 비교 분석)

  • Park, Heeseong;Lee, Du Han
    • Ecology and Resilient Infrastructure
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    • v.8 no.4
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    • pp.233-244
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    • 2021
  • This study investigated the application of terrestrial light detection and ranging (LiDAR) to inspect the defects of the vegetated levee. The accuracy of vegetation filtering techniques was compared by applying filtering techniques on photogrammetric point clouds of a vegetated levee generated by terrestrial LiDAR. Representative 10 vegetation filters such as CIVE, ExG, ExGR, ExR, MExG, NGRDI, VEG, VVI, ATIN, and ISL were applied to point cloud data of the Imjin River levee. The accuracy order of the 10 techniques based on the results was ISL, ATIN, ExR, NGRDI, ExGR, ExG, MExG, VVI, VEG, and CIVE. Color filters show certain limitations in the classification of vegetation and ground and classify grass flower image as ground. Morphological filters show a high accuracy of the classification, but they classify rocks as vegetation. Overall, morphological filters are superior to color filters; however, they take 10 times more computation time. For the improvement of the vegetation removal, combined filters of color and morphology should be studied.

The Results Comparison of Measurement and Simulations in ISL(Integrated Schottky Logic) Gate (ISL 게이트에서 측정과 시뮬레이션의 결과 비교)

  • 이용재
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.1
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    • pp.157-165
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    • 2001
  • We analyzed the electrical characteristics of platinum silicide schottky junction to develope the voltage swing in Integrated Schottky Logic gates, and simulated the characteristics with the programs in this junctions. Simulation programs for analytic characteristics are the Medichi tool for device structure, Matlab for modeling and SUPREM V for fabrication process. The silicide junctions consist of PtSi and variable silicon substrate concentrations in ISL gates. Input parameters for simulation characteristics were the same conditions as process steps of the device farications process. The analitic electrical characteristics were the turn-on voltage, saturation current, ideality factor in forward bias, and has shown the results of breakdown voltage between actual characteristics and simulation characteristics in reverse bias. As a result, the forward turn-on voltage, reverse breakdown voltage, barrier height were decreased but saturation current and ideality factor were increased by substrates increased concentration variations.

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