• 천문학회보
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• 제46권1호
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• pp.32.3-33
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• 2021

We present H I gas kinematics and star formation activities of NGC 6822, a dwarf galaxy located in the Local Volume at a distance of ~ 490 kpc. We perform profile decomposition of the line-of-sight velocity profiles of the high-resolution (42.4" × 12" spatial; 1.6 km/s spectral) H I data cube taken with the Australia Telescope Compact Array (ATCA). For this, we use a new tool, the so-called BAYGAUD (BAYesian GAUssian Decompositor) which is based on Bayesian Markov Chain Monte Carlo (MCMC) techniques, allowing us to decompose a line-of-sight velocity profile into an optimal number of Gaussian components in a quantitative manner. We classify the decomposed H I gas components of NGC 6822 into bulk-narrow, bulk-broad, and non_bulk with respect to their velocity and velocity dispersion. We correlate their gas surface densities with the surface star formation rates derived using both GALEX far-ultraviolet and WISE 22 micron data to examine the impact of gas turbulence caused by stellar feedback on the Kennicutt-Schmidt (K-S) law. The bulk-narrow component that resides within r25 is likely to follow the linear extension of the Kennicutt-Schmidt (K-S) law for molecular hydrogen (H2) at the low gas surface density regime where H I is not saturated.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권2호
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• pp.60-64
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• 2001

The degradation process of silicone rubber was investigated by leakage current monitoring in Inclined-Plane method. DAS (Data Acquisition System) with 12-bit, 8-channel A/D converter was prepared. Average current, cumulative charge, current waveform and the number of peak pulses were measured on-line. And, FFT (Fast Fourier Transform) analysis was performed with stored current waveform. Besides, maximum erosion depth was measured in order to use as the indicator of the degradation process. So, the results of leakage current components and maximum erosion depth measurements were compared to find one or more components which have trends of changing similarly to that of erosion process. The result suggests that the ratio of peak current to r.m.s. current, harmonic contents and the number of peak pulses are well corresponding with the degradation process.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1993년도 가을 학술발표회논문집
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• pp.193-198
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• 1993

This paper presents a systematic procedure to obtain shape functions of the infinite elements for soil-structure interaction analysis. The function spaces are derived from the analytical solutions and appropriate assumptions based on physical interpretation. The function spaces are complete for the surface wave components, but approximate for the body wave components. Three different infinite elements are developed by using the wave functions of the derived function spaces. Numerical example analysis is presented for demonstrating the effectiveness of the present infinite elements.

• 마이크로전자및패키징학회지
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• 제9권3호
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• pp.13-17
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• 2002

LTCC를 이용하여 2차원, 3차원 회로를 구성하는 경우에 R, L, C의 수동소자 이외에 stripline이나 microstripline인 같은 전송선로들이 첨가되게 된다. 따라서 이러한 전송선로들에 대한 정확한 분석을 필요로 하게 된다. 전송선로의 특성에서 유전체의 유효 유전율과 유전체 손실값, 도체의 유효 전기전 도도와 같은 물성치와 도체 및 유전체 표면의 거칠기, 구조의 크기와 같은 기하학적인 특성들이 영향을 주게 된다. 본 연구에서는 스트립라인 구조을 대상으로 위의 물성치와 구조에 관한 변수들을 정량화 함으로써 stripline구조를 분석하고 그 특성을 정량화하였다.

• 한국공작기계학회논문집
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• 제14권6호
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• pp.110-116
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• 2005

A single-piece-machined-part has superior characteristics to an assembly of several pieces of part especially for aircraft components. It is necessary to develop high efficient 'multi-head router machine' for machining a large size single-piece-part on a large scale. In this type machine, many cutting chips are generated. These chips should be removed automatically f3r productivity and part precision. In this study, the design evaluation of the cutting chip collecting apparatus for 'multi-head router machine' was complemented using performance test and finite element analysis.

• 기술혁신연구
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• 제22권4호
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• pp.165-198
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• 2014

탈추격형 혁신체제가 강조됨에 따라 국가연구개발사업은 기술역량 향상에 초점을 맞춰온 기존의 방식과 달리 문제해결 실용화 사회적 영향을 모두 아우른 통합적 접근을 필요로 한다. 이러한 상황에서는 R&D예산의 효과적 효율적 집행과 성과관리가 중요한 과제이나, 기존의 성과평가제도는 획일적 평가, 양적지표 위주 등으로 인해 한계를 가지고 있다. 본 연구에서는 이러한 문제점에 대응하기 위해 우리나라의 국가연구개발사업 성과평가의 진화과정을 조사 분석 평가 체제와 1,2차 성과평가기본계획 체제 세 시기로 나누어 제반 법 제도, 평가체제 및 내용, 평가의 활용 등의 요소를 비교분석하였다. 성과평가제도는 조사 분석 평가에서 1차 기본계획, 2차 기본계획으로 이행되면서 R&D자원 투입에 따른 양적 성과관리 위주에서 연구사업의 다각적 측면을 평가하기 위한 수단으로 진화하였다. 그 과정에서 평가인프라, 표준성과지표 등 평가체계의 고도화 실효성을 제고하기 위한 제도적 장치가 다수 마련되었다. 1차 기본계획에서는 과학기술행정체계의 잦은 개편이 성과평가 진화의 일관성에 영향을 미쳤으나, 2차 기본계획 이후 체계가 안정화되면서 성과평가제도는 우리나라 혁신시스템 전환을 뒷받침할 수 있는 방향으로 개선되고 있다.

• 한국전기전자재료학회논문지
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• 제37권2호
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• pp.208-214
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• 2024

This reports the electrical properties of single-crystal β-gallium oxide (β-Ga₂O₃) vertical Schottky barrier diodes (SBDs) with a different guard ring structure. The vertical Schottky barrier diodes (V-SBDs) were fabricated with two types guard ring structures, one is with metal deposited on the Al₂O₃ passivation layer (film guard ring: FGR) and the other is with vias formed in the Al₂O₃ passivation layer to allow the metal to contact the Ga₂O₃ surface (metal guard ring: MGR). The forward current values of FGR and MGR V-SBD are 955 mA and 666 mA at 9 V, respectively, and the specific on-resistance (R_on,sp) is 5.9 mΩ·cm² and 29 mΩ·cm². The series resistance (R_s) in the nonlinear section extracted using Cheung's formula was 6 Ω, 4.8 Ω for FGR V-SBD, 10.7 Ω, 6.7 Ω for MGR V-SBD, respectively, and the breakdown voltage was 528 V for FGR V-SBD and 358 V for MGR V-SBD. Degradation of electrical characteristics of the MGR V-SBD can be attributed to the increased reverse leakage current caused by the guard ring structure, and it is expected that the electrical performance can be improved by preventing premature leakage current when an appropriate reverse voltage is applied to the guard ring area. On the other hand, FGR V-SBD shows overall better electrical properties than MGR V-SBD because Al₂O₃ was widely deposited on the Ga₂O₃ surface, which prevent leakage current on the Ga₂O₃ surface.

• 한국IT서비스학회지
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• 제2권2호
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• pp.15-29
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• 2003

This thesis suggests a R&D model for Korean SI companies who aggressively drive oversea business to overcome domestic market limitation and to become world class SI players. Even though there have been a lot of discussions on IT technologies and new business models, scientific approach to a R&D model for SI companies is rare due to its natural distinctiveness from manufacturing and general service domain. Therefore, this will be a flagship thesis to keep up our study. As business market environment gets more competitive, major Korean SI players will be confronted with much more keen competition among themselves. And as they are willing to expand their oversea market presence, they can not help struggling against global SI players. So, here we are presenting SI players the reinforcement of R&D as one of the key components to build up their own core competencies. That is, SI players have to adopt and evaluate fast changing and complicated IT technologies at the right time, and to apply them into a real business with cost-effective service delivery and operation processes internally. The ultimate purpose of all of these activities is to offer a SI company the value added business model based on its innovative technical capabilities and well refined service deliver model. For this purpose, we suggests, SI company's R&D has to play an important role of emerging technology verification/evaluation/utilization, value added business model creation, future innovation lead, standard body participation, and effective service delivery and quality system development. To become a more effective R&D organization, hybrid R&D, in which central R&D and divisional sub R&D work together, is considered as an idea model. The reliability of the R&D model for Korean SI companies', here we suggest, has been checked by SI companies R&D specialists and on-site business people.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (3)
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• pp.765-767
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• 1998

Many application in human computer interaction(HCI) require tacking a human face and facial features. In this paper we propose efficient parallel processing system for face tracking under heterogeneous networked. To track a face in the video image we use the skin color information and connected components. In terms of parallelism we choose the master-slave model which has thread for each processes, master and slaves, The threads are responsible for real computation in each process. By placing queues between the threads we give flexibility of data flowing

• 한국작물학회:학술대회논문집
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• 한국작물학회 1992년도 춘계 학술대회지
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• pp.134-135
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• 1992