• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.28-31
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• 1999

Carbon fiber/epoxy composites using electrodeposited monomeric and polymeric coupling agents were compared with the dipping and the untreated cases. Treating conditions such as time, concentration and temperature were optimized. Four-fibers embedded micro-composites were prepared for fragmentation test. Interfacial properties of four-fiber composites with different surface treatments were investigated with simultaneous acoustic emission (AE) monitoring. The microfailure mechanisms occurring from fiber break, matrix and interlayer crackings were examined by AE parameters and an optical microscope. It was found that interfacial shear strength (IFSS) of electrodeposited carbon fibers was much higher than the other cases under dry and wet conditions. Well separated and different-shaped AE groups occurs for the untreated and ED treated case, respectively.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 하계학술연구발표회 및 한.일 공동심포지엄
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• pp.150-151
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• 2003

In the past years, a giant magnetoresistance (GMR) effect found in perovskite-like structured materials has attracted considerable attention among scientists and manufacturers, since, a practical point of view, the capacity of producing magnetic and sensing sensors. In a stream of this interest, further efforts to understand the underlying mechanism that leads to the GMR effect relative to the correlation between transport and magnetic properties, have been extensively devoted. In these cases, spin-glass-like behaviors are ascribed to the frustration of random competing exchange interactions, namely the ferromagnetic double-exchange interaction between Co$\^$3+/ (or Mn$\^$3+/) and Co$\^$4+/(or Mn$\^$4+/) and the antiferromagnetic one like spins. Noticeably, the distinction of spin-glass region from cluster-glass one, involved in the remarkable changes in transport and magnetic properties at a critical value of doping concentration, was observed. Magnetic anomalies in zero-field-cooled (ZFC) magnetization as well as ac magnetic susceptibility below Curie temperature T$\sub$c/ and the charge/orbital fluctuation were also realized. In this work, we present a study of magnetic properties of a deficient manganese perovskites system of La$\sub$0.6/Sr$\sub$x/MnTi$\sub$y/O$_3$, and particularly provide its new magnetic phase diagram.

• 한국컴퓨터정보학회논문지
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• 제23권3호
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• pp.9-16
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• 2018

In this paper, I purpose one of the development methods for portable Automatic field Test Equipment(ATE) with VME form factor. Almost portable ATE have not used to standards form factor and they are connected by mechanical non-rigid general connectors and wire harnesses among the components. Furthermore, it is hard to reuse developed board. So, it decreases to reusability of developed board and it is hard to maintenance of ATE. Even those things have weakness for vibration and drop test especially in portable ATE. The XK9A1 ATE using VME form factor has environmental reliability through vibration, drop, temperature test. It consists of 5 developed board called the control board, the wire & wireless communication board, the power supply board, the load board and the mother board. It is connected by two wire harnesses between mother board and extern circular connectors. The control board send the data and address to other board though each 16-bit data and 20-bit address line. You can develop the function board what you want to using those data & address line when it comes to needing other function board.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1319-1324
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• 2007

Many researches have been performed to analyze the smoke movement in tunnel fires by using field model. Recently, FDS(Fire Dynamics Simulator) v.4, which is one of the field model and developed from NIST(National Institute of Standards and Technology), is widely used. In tunnel fires, FDS can show detail results in local point, but it has difficulties in boundary condition and taking long computing time as the number of grid increases. So, there is a need to use alternative method for tunnel fire simulation. A zone model is different kind of CFD method and solves ordinary differential equation based on conservation and auxiliary equations. It shows good macroscopic view in less computing time compared to field model. In this study, therefore, to confirm the applicability of CFAST in tunnel fire analysis, numerical simulations using CFAST are conducted to analyze smoke movement in longitudinal ventilation reduced-scale tunnel fires. Then the results are compared with experimental results. The differences of temperature and critical velocity between numerical results and experimental data are over $30^{\circ}C$ and 0.9m/s, respectively. These values are out of error range. It shows that CFAST 6.0 is hard to be used for tunnel fire simulation.

• 한국광학회지
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• 제8권5호
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• pp.366-371
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• 1997

기체상태의 루비듐 원자가 실온에서 Maxwell 속도 분포를 이루고 있을 때 광펌핑 현상과 특정 속도 원자의 선택에 의해 도플러 효과를 제거시키는 속도군 선택 광펌핑(VSOP) 분광학을 실시하였다. 본 실험에서는 주파수가 고정된 locked laser와 주파수 튜닝이 가능한 sweep laser를 동시에 사용하되, 두 빔을 같은 방향으로 진행시키고, 시료 속에서 서로 겹치게 함으로써 주공진 신호만을 발생시킬 수 있었다. 이 방법으로 지금까지 알려진 VSOP 분광학보다 원자들의 속도 선택 범위가 더 넓어졌다.

• Progress in Superconductivity
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• 제13권3호
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• pp.178-183
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• 2012

Two $RuSr_2(EuCe)Cu_2O_z$ samples (as prepared and after $N_2$ treatment) have been investigated by thermogravimetric (TC) analysis, high-resolution x-ray powder diffraction and magnetization measurements. TG measurements which were carried out in $H_2/Ar$ atmosphere showed that the $N_2$ treatment of the as-prepared sample at $650^{\circ}C$ for 2h leads to a decrease in the oxygen content z by about 0.25. This oxygen depletion was accompanied by an increase in the magnetic transition temperature from 54.0 K to 114.9 K. This magnetic behavior is discussed in connection with the results of Rietveld analysis of the x-ray diffraction data which showed that the $N_2$ treatment resulted in both a significant increase in the rotation angle of the $RuO_6$ octahedra and a decrease in c-lattice parameter of the sample.

• 한국식품위생안전성학회지
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• 제2권3호
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• pp.89-95
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• 1987

시판 갈근으로부터 Isoflavanoid 성분인 Daidzein과 Daidzin을 분리 정제하고 이를 표준물질로 하여 시판 칡차 8종에 대한 칡성분 분석을 HPLC 방법으로 시도하여 다음과 같은 결론은 얻었다. 1. 칡차의 성분 분석법은 종래의 TLC법에 비하여 HPLC를 이용, 신속하고 정확하게 분석할 수 있었다. 2. 추출방법에 따라 성분함량이 크게 영향을 받아 Daidzein을 분석할 경우는 냉침법이, Daidzin의 분석시는 가열 추출법이 양호하였다. 3. 한국산 갈근중 Daidzein과 Daidzin은 0.08% 및 0.66% 함유되었다. 4. 시판 칡차중 고형차류는 칡의 성분이 표기량에 비하여 매우 적게 함유되거나 전혀 함유되지 않은 예도 있으며 액상차의 경우는 엑기스 고형분이 4∼5%가 함유되었다.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.83-88
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• 2003

The concept of lean-premixed combustion in gas turbine combustor operation has become a standard in recent years as an effective means to meet stringent environmental standards on NOx emissions. Various types of air-fuel premixer, which affect greatly NOx emission and stability of lean-premixed low NOx combustor, were investigated experimentally to reduce the NOx emission. One type of the premixers is selected by experiments and applied it to 70kW class lean-premixed gas turbine combustor. The exit temperature and emissions of CO and NOx were measured with equivalence ratios at ambient pressure. From the results, the emissions of CO and NOx were influenced by the type of air-fuel premixer. As the mixing length of air and fuel is longer, the NOx and CO emission were decreased in the primary reaction zone. Compared with of conventional combustor, the lean-premixed low NOx combustor has low NOx emission characteristics.

• 한국문헌정보학회지
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• 제25권
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• pp.215-232
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• 1993

The Long-Term Development Plan of the Pusan National University(PNU) has announced on 1991 in order to reach its roles and levels as an University with international standards, a Graduate School research-oriented and a core university in its community through accomplishment of this Plan. University libraries would be planned to support their universities' goals. Therefore the Library of PNU is facing on the task for supporting the Plan. The Collection for Korean Classical Materials (CKCM) is not limited in Korean Literature, Korean History, Korean Philosophy fields but covered the academic fields except a hightech science : Humanities, social science. pure science, applied science and arts etc. However, the Library of PNU does not have the organization, special librarian and budget for CKCM. Under this notion organization, budget and librarian for the collection would be followed. The CKCM contains the original editions, photography editions, copied issues. microform reproductions with comprehensive subjects in the fields of studies. Especially for the collection of treasure books the role of the Library of PNU induce to open individuals' collections or families' collections to public through the Library. The equipments for preserving rare books and treasure books are the conditioners for humidity and temperature, automatic extinguishment system. The reference materials, copy machine and reading room are requested for the user service of CKCM. The materials would be one of the most important thing in study and research. Therefore the Library of PNU need to pay attention to develop and preserve CKCM.

• 한국정보통신학회논문지
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• 제15권10호
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• pp.2203-2208
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• 2011

본 논문에서는 컨테이너의 육상, 해상 수송간 안전운송을 위해 CSD 시스템에 기반한 응용 서비스 개발에 대해 기술한다. CSD 시스템에 기반하여 표준에 따른 응용 서비스 및 보안 서비스의 개발과 개발결과의 테스트 과정에 대해 기술하였다. CSD에 의한 보안기능 외에 운송중의 재난 예방을 위해 온도, 습도 및 충격센서를 이용한 컨테이너 화물 상태감시 기능도 개발되었다. 응용 서비스와 CSD 시스템간에 교환되는 메시지 기밀성을 위해 데스크탑 PC 이상의 시스템 환경과 8 bit CPU 환경에서 각각 RC5, AES-128 알고리즘에 따른 암/복호화 기능을 구현하였다. 암/복호화 시간에 대한 측정 결과, 두 알고리즘 모두 사용 가능함을 확인하였다.