• 한국주조공학회지
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• 제27권2호
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• pp.83-87
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• 2007

Aluminum plates of the same materials as the foam were attached by the casting process inserting the foam as a core to investigate the tensile property of open cell foams. Tensile properties of the open cell 6063 aluminum alloy foam of $10{\sim}30$ PPI were measured before and after heat treatment. Densities of test specimens were between 0.14 and $0.29g/cm^3$. Tensile strength of the 6063 aluminum foam after heat treatment showed little change. C values were in the range of $0.41{\sim}0.87$ for as cast foams and $0.11{\sim}0.27$ for T6 heat treated foams in the eq. of ${\sigma}^* _{pl}/{\sigma}_{ys}=C({\rho}/{\rho}_s)^{1.5}$, and increased with increase in the cell size.

• 소성∙가공
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• 제19권7호
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• pp.399-404
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• 2010

We propose an analysis model for simulating the detailed procedure of pore closing in open die forging of shafts. In the analysis model, an artificial symmetric plane is used, on which initial pores are located to be traced. The analysis model is employed to carry out three-dimensional simulation of pore closing in shaft free forging by both conventional free forging press and radial forging machine. With this result, two typical types of free forging equipment for manufacture of shafts are compared in detail. It has shown that the radial forging machine is much superior to the conventional open die forging press especially in pore closing under high hydrostatic pressure with sound strain.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.767-771
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• 1997

The standards and technologies developed by the standard organizations and industry consortiums, which are being driven by the computer industry and are making the foundations of the open distributed systems are presented. Its benefits and impacts on EMS industry are described. This paper contains software architecture of open distributed system software. The proposing software architecture is aiming to develop all software highly versatile and open to third party hardware and software, and able to have the incremental modifications and additions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 전력전자학술대회
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• pp.270-272
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• 2018

This paper proposes an open-phase fault control system using 3-phase neutral voltage. The proposed control system is designed as a new topology which uses the potential difference between neutral point and ground(G) of three phase. And the open-phase detection system is configured to three resistance devices(Y-wiring) of the same capacity to each line of three phase power source R,S,T. This paper also designs a mobile phone application for remote alarm of open-phase fault.

• International Journal of Reliability and Applications
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• 제4권2호
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• pp.51-56
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• 2003

A k-out-of-n system with n identical and independent components is considered in which the components takes two types of function: 0 (open-circuit) or 1 (closed) on command (e.g. electromagnetic relays and solid state switches). Components are subject to two types of failure on command: failure to close or failure to open. In our k-out-of-n system, failure of (n-k)＋1 or more components to close causes to the close failure of the system, or failure of k or more components to open causes the open failure of the system. The long-run average cost rate is obtained. We find the optimal k minimizing the long run average cost rate for given n. A numerical example is presented.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2001년도 춘계 학술대회지
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• pp.82-83
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• 2001

[ $\circ$ ] HPLC상에서 saponarin의 retention time은 12.37분이었고, 표준물질에 의한 검량식은 Y=0.0513X-4.6182($R^2$=0.9982)이었다. $\circ$ 생육단계에 따라 saponarin 함량의 차이를 보여서 본엽 4매일 때 100g의 잎에는 강보리 447mg, 부강 437mg, 남향보리 395mg, 사천6호 370 mg, 탑골보리 219mg 순이었다. $\circ$ Saponarin 함량이 높은 품종의 잎에서 항산화능력이 높은 것으로 나타났다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 추계학술대회
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• pp.4-6
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• 2018

This paper proposes an open-phase fault control system using 3-phase neutral voltage. The proposed control system is designed as a new topology which uses the potential difference between neutral point and ground(G) of three phase. And the open-phase detection system is configured to Y-wiring of three capacitance devices of the same capacity to each line of three phase power source R-S-T. This paper also designs a mobile phone application for remote alarm of open-phase fault.

• 전자통신동향분석
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• 제38권3호
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• pp.78-85
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• 2023

This paper presents a review of standardization activities toward the interoperability between different metaverse platforms, which is a research hotspot in the metaverse. The metaverse is often considered as the evolution of the current mobile Internet. Like for the Internet, interoperability is essential to provide continuous user experiences over different metaverse service environments. However, current metaverses have limitations in providing interoperability in terms of portability of services, digital objects, such as identity and avatars, and economic systems. To address these limitations, the metaverse industry and open-source communities have recently begin to develop metaverse interworking standards. We describe activities conducted by various representative standardization bodies such as the Metaverse Standardization Forum, W3C (World Wide Web Consortium) Open Metaverse Interoperability, Open Metaverse Foundation, Open Metaverse Alliance for Web3, and Metaverse Alliance. In addition, we discuss how to counteract interoperability issues from the Korean perspective.

• 대한전자공학회논문지TC
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• 제45권1호
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• pp.103-109
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• 2008

본 논문에서는 FSCS를 이용한 고조파가 억제된 ${\lambda}_g/4$ 단락형 스터브 대역통과 여파기와 ${\lambda}_g/2$ 개방형 스터브 대역통과 여파기를 새로운 구조로 제안 설계하였다. 제안된 여파기는 FSCS를 이용한 광대역 대역저지 여파기를 대역통과 여파기에 집적화 시켜 제2 고조파를 억제하였고, 스터브 사이에 BSF를 집적화하여 크기의 증가를 방지하여 22% 감소하였다. 제안된 여파기는 중심주파수 5.8 GHz에서 통과 대역폭 50%, 고조파 저지대역 120% 광대역 대역통과 여과기의 특성을 나타내었고, ${\lambda}_g/4$ 단락형 스터브 여파기의 경우 삽입손실 0.5 dB, 반사손실 14 dB의 측정결과를 ${\lambda}_g/2$ 개방형 스터브 여파기의 경우는 삽입손실 0.8 dB, 반사손실 14.4 dB의 측정결과를 얻었으며, 시뮬레이션 결과와 측정결과가 유사하게 나타났다.

• 한국통신학회논문지
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• 제33권2A호
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• pp.167-173
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• 2008

본 논문에서는 $\{lambda}$g/4 단락형 및 ${\lambda}$g/2 개방형 스터브를 이용한 협대역 대역통과 여파기를 제안한다. 스터브 대역 통과 여파기를 협대역으로 구현하기 위해, 스터브의 임피던스 값 변화 없이 스터브 위치를 변화시켜, 그에 따른 Qe (External quality factor) 값을 이용하여 협대역 대역통과 여파기를 구현한다. 또한, 협대역 대역통과 여파기의 전승선로 부분에 T-형태의 대역저지 여파기를 집적시켜, 여파기에서 발생하는 고조파들을 억제한다. 제안된 여파기의 중심 주파수는 5.8 GHz, 대역폭은 10 % 이며, ${\lambda}$g/4 단락형에서의 삽입손실은 2.1 dB, 반사손실은 18 dB이고, ${\lambda}$g/2 개방형에서의 삽입손실은 1.2 dB, 반사손실은 21.9 dB의 측정결과들을 얻는다.