Alloy 600 노즐관통부의 이종금속용접 잔류응력에 따른 응력부식균열 거동 분석

김성우,김홍표,김동진,정재욱,장윤석,Kim, Sung-Woo,Kim, Hong-Pyo,Kim, Dong-Jin,Jeong, Jae-Uk,Chang, Yoon-Suk 한국압력기기공학회 2010 한국압력기기공학회 논문집 Vol.6 No.2

This work is concerned with the analysis of stress corrosion cracking(SCC) behavior of Alloy 600 nozzle penetration mock-up according to a residual stress induced by a dissimilar metal welding(DMW) in a nuclear reactor pressure vessel. The effects of the dimension and materials of the nozzle penetration on the deformation and the residual stress induced by DMW were investigated using a finite element analysis(FEA). The inner diameter(ID) change of the nozzle by DMW and its dependance on the design variables, calculated by FEA, were well consistent with those measured from the mock-up. Accelerated SCC tests were performed for three mock-ups with different wall thicknesses in a highly acidic solution to investigate mainly the effect of the residual stress on the SCC behavior of Alloy 600 nozzle. From a destructive examination of the mock-up after the tests, the SCC behavior of the nozzle was fairly related with the residual stress induced by DMW : axial cracks were found in the ID surface of the nozzle within the J-weld region where the highest tensile hoop stress was predicted by FEA, while circumferential cracks were observed beyond both J-weld root and toe where the highest tensile axial stress was expected.

${Y_2}{SiO_5}:Ce$ 청색 형광체의 표면 코팅에 따른 음극선 발광특성

김성우,이임렬,Kim, Seong-U,Lee, Im-Ryeol 한국재료학회 2000 한국재료학회지 Vol.10 No.8

$Y_2SiO_5:Ce$ 형광체를 $In_2O_3$, $Al_2O_3$ 및 $SiO_2$로 코팅한 후 전계 방출 디스플레이에 요구되는 음극선 발광 특성을 조사하였다. $Al_2O_3$ 코팅으로 $Y_2$SiO(sub)5:Ce 형광체의 발광 효율과 에이징 특성은 감소되었다. 한편 $Al_2$$O_3$코팅으로 형광체의 발광효율은 증가하였으나 발광스펙트럼과 색좌표는 일부 변화하였다. 그러나 $Y_2SiO_5:Ce$ 청색 형과체의 발광 효율은 $SiO_2$코팅으로 크게 증가하였으며, 또한 $SiO_2$ 코팅한 $Y_2SiO_5:Ce$ 형광체의 에이징 특성은 코팅 전에 비하여 크게 향상되었다. $Y_2SiO_5:Ce$ phosphor was coated with $In_2O_3$, $Al_2O_3$ and $SiO_2$ and then their cathodoluminance(CL)proper-ties required in field emission display were investigated. It was found that luminance efficiency and aging p개perty of $Y_2SiO_5:Ce$ phosphor was decreased with $In_2O_3$coating. For the case of coating, the luminance intensity was in blue phosphor was dramatically increased with $SiO_2$ coating. And also the aging property of $Y_2SiO_5:Ce$ Phosphor coated with $SiO_2$ was significantly improved compared to non-coated sample.

양돈농가의 효율적인 자금관리를 위한 경영전략(2)

김성우,Kim, Seong-U 대한양돈협회 1999 養豚 Vol.21 No.12

통일신라시대(統一新羅時代) 불교건축(佛敎建築)의 변화(變化)

김성우,Kim, Sung-Woo 한국건축역사학회 1992 건축역사연구 Vol.1 No.2

The development of Buddhist architectures of the Unified Silla period have been generally understood to have paired pagoda instead of one which had been popular until before the unification. Besides the stylistic categorization of paired pagoda system, there had been no further investigation reported concerning whether there was any detailed process of change within the development of paired pagoda style. This paper aims to identify such change inside the development of paired pagoda style, which, externally, seems to be the same pattern of site design maintained throughout the period of Unified Silla that lasted for about three centuries. Since the temple sites of study are in the same pattern of layout, the method of investigation has to be such that can identify the subtle changes that, in external appearance, are not easily discernible. Hence, this research compared the dimensions of important measurement of five temple sites to be able to clarify the process of minor changes. Among many sites of Silla temples, only five were suitable for the research since detailed measurement were possible through field research or the report of excavation. They are the sites of Sachonwang-sa, Mangduk-sa, site of Kunsuri, and Bulguk-sa. Although the five sites have the same style of paired pagoda, it is clear that there were consistant flow of change. Even though the motivation of such change were not strong enough to change the site pattern itself, it resulted continuous minor changes such as the size and location of architectures. The size of image hall, for example, was growing larger and larger as time goes on, while, the size of Pagoda was getting smaller. In the same way, the size of middle gate became smaller while the size of lecture hall became larger, although the rate of change in these cases were not as severe as that of image hall and pagoda. At the same time, pagoda was coming closer to the middle gate leaving larger space in front of the image hall. Such aspect is even more meaningful considering the fact that the pagoda, from the 8th century in Japan and China, moved outside of the major precinct. The image hall, too, moved toward the middle gate slightly so that the space in front of the lecture hall became more spacious. Such changes, of course, were not accidental but they are the same continuous motivation of change that caused the changes before the period of unification. Enlargement of image hall and reduction of pagoda, for example, represent the changing relative importance of religious meaning. Hence, it is evident that one can not easily imterprete the development of one style only by categorizing it to be one same style. In the veiwpoint of the underlying motivation of change, the fact that one style persisted for a certain period of time, does not mean there had been no change, but means that it was the time of motivational accumulation, causing minor changes within the same style, to be able to create major change coming after.

Measurement of Electron Beam Output for the Prototype Compact Linac

김성우,강상구,이동주,임희진,이만우,이준규,이무진,양광모,노태익,정동혁,Kim, Sung-Woo,Kang, Sang Koo,Rhee, Dong Joo,Lim, Heuijin,Lee, Manwoo,Yi, Jungyu,Lee, Mujin,Yang, Kwangmo,Ro, Tae Ik,Jeong, Dong Hyeok Korean Society of Medical Physics 2015 의학물리 Vol.26 No.1

The C-band compact linear accelerator (linac) is being developed at Dongnam Institute of radiological & Medical Sciences (DIRAMS) for medical and industrial applications. This paper was focused on the output measurement of the electron beam generated from the prototype electron linac. The dose rate was measured in unit of cGy/min per unit pulse frequency according to the IAEA TRS-398 protocol. Exradin-A10 Markus type plane parallel chamber used for the measurement was calibrated in terms of dose to water at the reference depth in water. The beam quality index ($R_{50}$) was determined by the radiochromic film with a solid water phantom approximately due to low energy electrons. As a result, the determined electron beam output was $17.0cGy/(min{\cdot}Hz$. The results were used to monitor the accelerator performance during the development procedure. 의료용 및 산업용으로 활용하기 위한 C-밴드형 콤팩트 선형가속기의 개발이 동남권원자력의학원에서 진행되고 있다. 본 논문에서는 선형가속기 시작품에서 발생한 전자빔의 출력 측정 결과를 보고하고자 한다. 출력 측정은 물흡수선량에 대해 교정된 Exradin-A10 마커스형 평행평판형 전리함을 사용하여 물속 기준 깊이에서 IAEA TRS-398 프로토콜에 따라 흡수선량율을 결정하는 과정으로 진행되었다. 전자선 에너지가 낮은 점으로 인하여 선질지표($R_{50}$)은 필름 측정법을 써서 근사적으로 결정하였다. 결과로서 단위 펄스 진동수당의 선형가속기 전자빔의 출력은 $17.0cGy/(min{\cdot}Hz$로 나타났다. 본 연구의 결과는 개발 중인 전자가속기의 성능 평가 자료로 활용될 것이다.

기동헬기 측면항법 알고리즘 구현 및 검증

김성우,고은경,Kim, Sung-woo,Go, Eun-kyoung 한국정보통신학회 2018 한국정보통신학회논문지 Vol.22 No.2

본 논문은 비행제어 비행체 관리 시스템 대신 한국형 기동헬기 임무컴퓨터의 비행운용 프로그램에서 구현한 측면 항법 알고리즘 설계 및 검증에 대하여 기술하였다. 구현된 측면항법 기능은 비행제어 시스템으로 롤 명령을 보내고 롤 명령 값은 임무컴퓨터의 제어 알고리즘에서 계산한다. 임무컴퓨터에서 제어 알고리즘 계산 시 항공기의 자세 및 위치에 대한 측정값을 이용한다. 이 입력 값들을 이용하여 임무컴퓨터에 탑재된 비행운용 프로그램은(선택한 비행계획 등)항법 요구를 롤 명령으로 자동조종으로 보낸다. 체계통합리그에서의 통합시험, 지상 및 비행시험을 통해 측면 항법 알고리즘을 검증하였다. This paper describe the Lateral Navigation algorithm design and verification that implementation on Mission Computer's OFP for Korean Utility Helicopter(KUH) instead of Auto Flight Control System(AFCS) Vehicle Management System. The LNAV function transmits Roll command into the AFCS System. The Roll command value will be calculated by control algorithms in MC. The Operational Flight Program(OFP) shall use for its calculations different measurements of the aircraft's attitude and place. Using these inputs, the OFP will translate a navigational demand(for example-to perform the selected flight plan) into Roll commands to the autopilot. By conducting integration test using SIL and ground test, flight test, it is confirmed that the introduced algorithm meets the requirements of the Mission Equipment Package(MEP) system. LNAV function is verified through the System Integration Laboratory(SIL) test, ground and flight test.

방향성이 높은 사운드 빔 형성 알고리즘

김성우,허유미,박영철,윤대희,Kim, Seona-Woo,Hur, Yoo-Mi,Park, Young-Chul,Youn, Dae-Hee 한국음향학회 2010 韓國音響學會誌 Vol.29 No.1

본 논문에서는 스피커 어레이를 사용하여 높은 방향성을 가진 사운드 빔을 형성하는 알고리즘을 제안하고, 제안된 알고리즘을 멀티 채널 3D사운드 시스템에 적용하는 방법을 설명한다. 제안된 알고리즘은 두 과정을 거친다. 첫 번째 과정에서는 표적 지점과 제어 영역간의 음향 파워 비를 최대화 하는 최적 빔 형성 계수를 구하고, 다음 과정에서는 상관행렬을 조절해 가면서 사운드 빔의 방향성을 반복적으로 향상시킨다. 여러 가지 상황에서 제안된 알고리즘의 성능을 평가하였으며, 실험 결과는 제안된 알고리즘이 기존의 방법들에 비해 더 높은 방향성을 갖는 사운드 빔을 제공함을 보였다. This paper proposes a technique of sound beamforming that can generate high-directive sound beams, and this paper also presents applications of the proposed algorithm to multi-channel 3D sound systems. The proposed algorithm consists of two phases: first, optimum weights maximizing a sound pressure level ratio between the target and control acoustic regions are designed, and later, the directivity of the pre-designed sound beam is iteratively enhanced by modifying the covariance matrix. The proposed method was evaluated under various situations, and the results showed that it could provide more focused sound beams than the conventional methods.

Mo / SiO2 촉매상에서 t - Butyl hydroperoxide 에 의한 염화알릴의 에폭시화반응에 관한 속도론적 연구

김성우,박대원,정종식,박대철 ( Sung Woo Kim,Dae Won Park,Jong Shik Chung,Dae Chul Park ) 한국공업화학회 1992 공업화학 Vol.3 No.4

t-Butyl hydroperoxide(TBHP)에 의한 염화알릴의 에폭시화에 의해서 에피클로로히드린을 합성하는데 실리카에 담지된 몰리브데늄 촉매를 사용하였다. 속도론적 연구는 회분 반응기를 사용하여 60-80℃, 10기압에서 TBHP/염화알릴의 농도비를 0.01-0.1의 범위내에서 수행하였다. t-butyl alcohol(TBA)에 의해서 염화알릴의 에폭시화 반응이 억제되었고 반응속도는 Michaelis-Menten 형태의 속도식으로 표현할 수 있었다. 반응기구는 TBHP와 TBA의 가역흡착과 Mo/SiO_2에 흡착된 TBHP와 염화알릴의 표면반응으로 설명할 수 있었다. The synthesis of epichlorohydrin was carried out by the epoxidation of allyl chloride with tert-butyl hydroperoxide(TBHP) over silica supported molybdenum catalyst. Kinetic study was performed at 60-80℃ and 10 atm with the molar ratio of TBHP/Allyl chloride between 0.01 and 0.1 in a batch reactor. The epoxidation of allyl chloride was inhibited by tert-butyl alcohol and kinetic data could be represented by Michaelis-Meten type rate equation. The reaction mechanism could be explained by the combination of reversible adsorption of TBHP and tert-butyl alcohol accompanied by reaction of allyl chloride with TBHP adsorbed on Mo/SiO_2 catalyst.

주택의 배치 및 평면의 변화를 중심으로 본 재래식 농촌주택의 근대화 과정에 관한 연구 - 경기도 용인군 용인읍 삼가 1,3리 마을 주택을 중심으로 -

김성우,이유미,Kim, Sung Woo,Lee, You Mee 한국건축역사학회 1995 건축역사연구 Vol.4 No.1

The study is about the process of modernization of conventional rural houses in Kyung-gi province. It alms to identify the pattern of change, particularly focusing on the changes of the site plan and plan. The site of study is Samga Village, in YongIn County, near Seoul. The study discusses the process of modernization during the three decades from 1960 to 1980. The basic information was obtained through field research and site analysis, and the study relies predominatly on observational and statistical analysis. Four developmental stages can be clearly identified which are ; (1) Traditional type, (2)Modified-traditional type, (3) Saemaul type, and (4) The type of urban houses. The analysis was done through identification of changing site plan and plan. It is interesting to note that the changes of these elements show a certain pattern of sequential steps which also can be classified according to the four developmental stages mentioned above. The pattern of site design was consistantly maintained while plan and building system became very different However, the process of modernization of Korean rural houses was the process of producing a certain type of architecture that is not universal but uniquely Korean.

망막분지정맥폐쇄에서 황반중심부의 후유리체박리가 황반부종에 미치는 영향

김성우,오인경,오재령,허걸,Seong Woo Kim,In Kyung Oh,Jae Ryung Oh,Kuhl Huh 대한안과학회 2006 대한안과학회지 Vol.47 No.3

Purpose: To quantitatively compare the role of posterior vitreous detachment in macular edema associated with branch retinal vein occlusion (BRVO) using OCT. Methods: A retrospective study of 36 eyes with BRVO-associated macular edema was carried out from November 2003 to February 2005. There was posterior vitreous detachment (PVD) in 23 eyes [PVD (+) group], and vitreoretinal attachment on the fovea in 31 eyes [PVD (-) group]. PVD was detected with an indirect ophthalmoscope or 90D lens. The foveal thicknesses of the two groups were measured and compared. Results: The mean foveal thicknesses of the PVD (-) and PVD (+) groups were 398.0±217.2 ?m and 233.6±80.6 ?m, respectively (p=0.000, Mann-Whitney test). The mean BCVA (log MAR) was 0.77±0.52 in the PVD (-) group and 0.40±0.37 in the PVD (+) group (p=0.002, Mann-Whitney test). Conclusions: The extent of macular edema associated with BRVO was significantly less in the PVD(+) group and BCVA was significantly better in the PVD (+) group as well.