• Information and Communications Magazine
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• v.13 no.5
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• pp.69-76
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• 1996

VOD 서비스는 가장 유망한 ATM 서비스의 하나로 간주되고 있으며 거의 모든 시럼 서비스에서 제공되고 있다. VOD 서비스는 응용분야 및 프로그램의 내용에 따라 여러 가지로 불리우고 있으며, 이러한 이유로 사람에 따라 서로 다른 뜻으로 쓰이는 경우가 많은 점을 고려하여 DAVIC 표준에서는 더 구체적으로 VOD 서비스를 분류하였다. DAVIC에 정의된 19가지의 서비스 중에서 VOD 서비스와 관련있는 것을 보면 Movies On Demand(MOD), Near Video On Demand(MOD), Karaoke On Demand(MOD), News On Demand(MOD)등이 있으며, 이외에도 유사한 서비스들이 있다. 본 고에서는 VOD 서비스를 제공하기 위하여 필요한 기술인 압축/복원, 전송 방식, 비디오 서버, Settop Box 등에 관하여 기술하였으며, 마지막으로 VOD 서비스 제공 예를 보였다.

• Korean Journal of Materials Research
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• v.13 no.12
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• pp.801-805
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• 2003

To explore the annealing temperature dependence of dielectric properties $Ta_2$$O_{5}$ thin films were prepared by MOCVD(metal-organic chemical vapor deposition) and MOD(metal-organic decomposition). The $Ta_2$$O_{5}$thin films fabricated MOCVD and MOD were annealed in $O_2$at temperature between 600 and 90$0^{\circ}C$. The measured dielectric constant of both films at 100 KHz was the highest value at $650^{\circ}C$ and decreased with increasing annealing temperature above $650^{\circ}C$. Plane-view SEM image showed that the boundary seems to be crack broke out with increasing annealing temperature. It was confirmed that outbreak of boundary influenced a decrease of dielectric constant with increasing annealing temperature. The leakage current density increased with increasing annealing temperature.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.103-109
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• 2013

Miller-Rabin method is the most prevalently used primality test. However, this method mistakenly reports a Carmichael number or semi-prime number as prime (strong lier) although they are composite numbers. To eradicate this problem, it selects k number of m, whose value satisfies the following : m=[2,n-1], (m,n)=1. The Miller-Rabin method determines that a given number is prime, given that after the computation of $n-1=2^sd$, $0{\leq}r{\leq}s-1$, the outcome satisfies $m^d{\equiv}1$(mod n) or $m^{2^rd}{\equiv}-1$(mod n). This paper proposes a step-by-step primality testing algorithm that restricts m=2, hence achieving 98.8% probability. The proposed method, as a first step, rejects composite numbers that do not satisfy the equation, $n=6k{\pm}1$, $n_1{\neq}5$. Next, it determines prime by computing $2^{2^{s-1}d}{\equiv}{\beta}_{s-1}$(mod n) and $2^d{\equiv}{\beta}_0$(mod n). In the third step, it tests ${\beta}_r{\equiv}-1$ in the range of $1{\leq}r{\leq}s-2$ for ${\beta}_0$ > 1. In the case of ${\beta}_0$ = 1, it retests m=3,5,7,11,13,17 sequentially. When applied to n=[101,1000], the proposed algorithm determined 96.55% of prime in the initial stage. The remaining 3% was performed for ${\beta}_0$ >1 and 0.55% for ${\beta}_0$ = 1.

• Bulletin of the Korean Mathematical Society
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• v.56 no.6
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• pp.1385-1422
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• 2019

Let p be an odd prime. The algebraic structure of all negacyclic codes of length $8_{p^s}$ over the finite commutative chain ring ${\mathbb{F}}_{p^m}+u{\mathbb{F}}_{p^m}$ where $u^2=0$ is studied in this paper. Moreover, we classify all negacyclic codes of length $8_{p^s}$ over ${\mathbb{F}}_{p^m}+u{\mathbb{F}}_{p^m}$ into 5 cases, i.e., $p^m{\equiv}1$ (mod 16), $p^m{\equiv}3$, 11 (mod 16), $p^m{\equiv}5$, 13 (mod 16), $p^m{\equiv}7$, 15 (mod 16) and $p^m{\equiv}9$ (mod 16). From that, the structures of dual and some self-dual negacyclic codes and number of codewords of negacyclic codes are obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3319-3325
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• 2012

This paper describes the development of the TrackSim, which is a discrete event simulation tool for photolithography equipment of semiconductor industry. The TrackSim is focused on the accurate simulation model of the photolithography equipment and easy-to-use user interfaces. TrackSim provides 3D simulation environment for evaluating, validating, and scheduling the photolithography process. One of the major characteristics of TrackSim is in that it is developed based on Applied Materials' AutoMod, a discrete event simulation software broadly used in semiconductor industry. Accordingly, the photolithography model of TrackSim can be used to perform simulation connected with other simulation models built with AutoMod.

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.79-79
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• 2003

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.92-92
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• 2003

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.76-76
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• 2003

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1321-1330
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• 2023

Normalized Difference Vegetation Index (NDVI) is the most widely used remote sensing data in the agricultural field and is currently provided by most optical satellites. In particular, as high-resolution optical satellite images become available, the selection of optimal optical satellite images according to agricultural applications has become a very important issue. In this study, we aim to define the most optimal optical satellite image when monitoring NDVI in rice fields in Korea and derive the resolution-related requirements necessary for this. For this purpose, we compared and analyzed the spatial distribution and time series patterns of the Dangjin rice paddy in Korea from 2019 to 2022 using NDVI images from MOD13, Landsat-8, Sentinel-2A/B, and PlanetScope satellites, which are widely used around the world. Each data is provided with a spatial resolution of 3 m to 250 m and various periods, and the area of the spectral band used to calculate NDVI also has slight differences. As a result of the analysis, Landsat-8 showed the lowest NDVI value and had very low spatial variation. In comparison, the MOD13 NDVI image showed similar spatial distribution and time series patterns as the PlanetScope data but was affected by the area surrounding the rice field due to low spatial resolution. Sentinel-2A/B showed relatively low NDVI values due to the wide near-infrared band area, and this feature was especially noticeable in the early stages of growth. PlanetScope's NDVI provides detailed spatial variation and stable time series patterns, but considering its high purchase price, it is considered to be more useful in small field areas than in spatially uniform rice paddy. Accordingly, for rice field areas, 250 m MOD13 NDVI or 10 m Sentinel-2A/B are considered to be the most efficient, but high-resolution satellite images can be used to estimate detailed physical quantities of individual crops.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.8
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• pp.694-699
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• 2000

S $r_{0.9}$/B $i_{2.1}$/T $a_{2}$/ $O_{9}$ solutions was synthesized by MOD (metalorganic decomposition) method. SBT thin films with 2000$\AA$ thickness were prepared on Ir $O_2$/ $SiO_2$/Si and Pt/Ti/ $SiO_2$/Si substrates using the spin coating process and then investigated the dielectric and electrical properties of them. In the case of using Ir $O_2$bottom electrode the hysteresis loop was saturated at lower temperature than Pt/Ti electrode but the breakdown phenomenon was occurred at low voltage because of the rough surface morphology and porous microstructure of SBT thin films. As the results of the fatigue and imprint characteristics related to the lifetime and reliability of devices after 10$^{10}$ cycles the fatigue rates were about 10% at the Ir $O_2$and Pt/Ti bottom electrodes. Both SBT thin films with Ir $O_2$ and with Pt/Ti bottom electrodes show a slight tendency to imprint after 10$^{9}$ cycles but do not lead to a failure.e.e.