해수교환 방파제에 작용하는 파력특성

오영민,이달수 한국해안해양공학회 2000 한국해안·해양공학발표논문집 Vol.11 No.1

Effect of V and Sb on the Characteristics of β to α Transformation in Zr-0.84Sn Alloy

오영민,정용환,김선진,O, Yeong-Min,Jeong, Yong-Hwan-Jeong,Kim, Seon-Jin-Kim Materials Research Society of Korea 2002 한국재료학회지 Vol.12 No.4

Effect of V and Sb content on characteristics of ${\beta}\;to\;{\alpha}$ phase transformation in Zr-0.84Sn alloy has been studied using optical microscopy and transmission electron microscopy. As V content increased, the ${\beta}{\to}{\beta}+{\alpha}$ transformation temperature was lowered, thus allowing the width of $\alpha$-lath in air-cooled Zr-0.86Sn-0.40V alloy to be fine. The width of ${\alpha}$-lath in air-cooled Zr-0.84Sn-xSb, however, was rarely changed with Sb content. The ${\beta}\;to\;{\alpha}$ transformed microstructures of water-quenched Zr-0.84Sn, Zr-0.84Sn-0.10V and Zr-0.84Sn-0.19V alloys were mainly slipped martensite. On the other hand, those of wafter-quenched Zr-0.86Sn-0.40V and Zr-0.85Sn-0.05Sb alloys were predominantly twinned martensite. In case of water-quenched Zr-0.85Sn-0.12Sb and Zr-0.84Sn-0.17Sb alloys, basketweave structure was observed. The transition of slipped martensite to twinned martensite in Zr-0.84Sn-xV alloys and the transition of twinned martensite to basketweave structure in Zr-0.84Sn-xSb alloys were due to the decrease of $M_s$ temperature.

원전 밸브용 경면처리 합금의 캐비테이션 에로젼 (cavitation erosion) 거동에 관한 연구

오영민,김윤갑,김선진,O, Yeong-Min,Kim, Yun-Gap,Kim, Seon-Jin 한국재료학회 2002 한국재료학회지 Vol.12 No.4

The cavitation erosion behavior of wear-resistant hardfacing alloys such as Co-base Stellite 6, Fe-base Norem 02 and new Fe-base alloy were investigated up to 50 hours by using a 20kHz vibratory cavitation erosion test equipment. The crack, initiated easily at the interfaces between matrix and hard second phase, was repressed effectively in Stellite 6 because the matrix was hardened by phase transformation. For this reason, Stellite 6 showed an excellent cavitation erosion resistance compared to Norem 02. The phase transformation also occurred in Norem 02, but the increase of volume fraction of the interfaces caused the crack to be initiated frequently, thus resulting in a 1arge material loss. The matrix of NewAlloy was hardened effectively by vlongrightarrow$\alpha$' phase transformation and the volume fraction of the interfaces was very small compared to Norem 02. This caused the propagation of crack to the matrix to be repressed effectively. Therefore, NewAlloy showed a very excellent cavitation erosion resistance. It wasn't considered that the cavitation erosion resistance of NewAlloy was influenced the temperature of the bath filled with a distilled water up to $80^{\circ}C$.

孟子의 人間本性論

吳永敏 광주가톨릭대학교 신학연구소 1987 神學展望 Vol.- No.79

지방의원의 구유통 정치와 사업예산의 분절화

오영민 서울행정학회 2010 한국사회와 행정연구 Vol.20 No.4

The concept of project budgetary fragmentation is a phenomenon or a trend that project budget cuts into small pieces by politically driven projects. Local legislators represent their own electoral districts needed to grant some benefit from the projects, because they want to win their competitors in next election. As a result of survey of local assembly legislators and local government bureaucrats, they agreed that a parochial interest and pork barrel politics of local legislators aggravated the project budgetary fragmentation. But, local bureaucrats and head of local government said that they have tried to prevent the degeneration of budgetary fragmentation.

TEP 측정방법을 이용한 Zr-0.8Sn 합금의 Nb 고용도에 관한 연구

오영민,정흥식,정용환,김선진,Oh, Yeong-Min,Jeong, Heung-Sik,Jeong, Yong-Hwan,Kim, Seon-Jin 한국재료학회 2001 한국재료학회지 Vol.11 No.6

미세조직에 따라 기계적 성질 및 내산화성.내부식성 등의 제반 성질이 크게 변하는 Zr계 핵연료 피복관은 미세조직의 최적화가 중요하다. 이러한 미세조직은 합금원소의 고용도에 크게 의존하지만, Zr은 대부분의 용질합금원소의 고용도가 매우 작아서 측정이 곤란하였다. 본 연구에서는 핵연료 피복관 재료의 주요한 기본조성 재료인 Zr-0.8Sn 합금에 대한 Nb의 고용도를 TEP 측정방법을 이용하여 연구하였으며, 광학현미경과 전자현미경으로 미세조직을 관찰하여 이를 확인하였다. 균질화 처리온도가 증가함에 따라 고용된 Nb 함량이 증가하여 Zr-0.8Sn 합금의 TEP는 감소하는 경향을 보였다. 처리온도가 더욱 증가하면 TEP의 포화가 발생하였는데 이는 TEP에 영향을 미치는 고용된 합금원소의 함량 변화가 없기 때문이다. 따라서, TEP의 포화영역이 나타나기 시작하는 균질화 처리온도가 첨가된 Nb이 Zr-0.8Sn 합금에 모두 고용되는 시점이며, 이를 토대로 온도에 따른 Zr-0.8Sn 합금에서의 Nb 고용도 ($C_{Nb}$ )를 $4.69097{\times}10^{16}{\times}e^{-25300\times\;I/T}$(ppm.at.%)로 나타낼 수 있었다. It is important for the fabrication of nuclear cladding to optimize the microstructure, because the properties of Zr-based nuclear claddings such as mechanical properties, oxidation-resistance and corrosion- resistance vary widely with its microstructure. The microstructure in Zr-based alloy is strongly dependent on the solubility of alloying element. However, it is very difficult to measure the solubility due to the low solution limit of alloying elements in Zr-based alloy. In this study, Thermoelectric Power(TEP) measurements are used to determine the solubility of Nb in Zr-0.8Sn alloy, which is confirmed by optical microscopy and transmission electron microscopy. The solutioning of Nb obtained by a homogenization treatment and water-quench leads to a decrease of TEP The saturation of TEP appears with the increase of homogenization temperature, which means the saturation of the Nb content in the matrix. From these results, the solubility ($C_{Nb}$) of Nb in Zr-0.8Sn with temperature could be expressed as fellow equation : $4.69097{\times}10^{16}{\times}e^{-25300\times\;I/T}$(ppm.at.%)

한국해양연구원 연안.항만공학연구본부 소개

오영민 한국수자원학회 2001 물과 미래(한국수자원학회지) Vol.34 No.3

시멘트 고화제 고결공법에서 발생하는 Cr6+의 환경영향 검토

오영민,김경태 한국해안,해양공학회 2002 한국해안해양공학회 논문집 Vol.14 No.4

Recently, the injection of cement stabilizer is used as one of ways to improve soft sea-botom.However, this method makes an argument with Cr6+subject to emerge to the seawater from the cement stabilizer.To investigate the amount of Cr6+field measurements were carried out in Ochun harbor of Chunsoo Bay. Theanalysis shows the amount of Cr6+in the seawater met the demand of environmental criterion.

시멘트 고화제 고결공법에서 발생하는 Cr⁶⁺의 환경영향 검토

오영민,김경태 한국해안해양공학회 2002 한국해안해양공학회 논문집 Vol.14 No.4

항만공사 시에 연약지반을 개량하기 위한 방법에는 여러 가지가 있는데 그 중에서 최근에 시멘트 고화제를 주입하는 방법이 많이 이용되고 있다. 그러나 이 방법은 시멘트 고화제에 함유된 6가 크롬(Cr⁶⁺)이 해수 중에 용출되어 수질환경을 악화시킬 수 있다는 논란이 일고 있다. 이러한 논란을 확인하기 위하여 현재 이 방법을 이용하여 연약지반 개량공사를 수행하고 있는 천수만의 오천항에서 현장관측을 실시하였다. 자료 분석결과, 용출수에서는 환경기준을 초과하는 Cr<sub>6+</sup>이 발견되지 않았다. Recently, the injection of cement stabilizer is used as one of ways to improve soft sea-bottom. However, this method makes an argument with Cr⁶⁺subject to emerge to the seawater from the cement stabilizer. To investigate the amount ofCr⁶⁺field measurements were carried out in Ochun harbor of Chunsoo Bay. The analysis shows the amount of Cr⁶⁺in the seawater met the demand of environmental criterion.

The Effect of Political Institutions on the Use of Citizen Participation Programs

오영민,박종선 서울대학교행정대학원 2013 The Korean Journal of Policy Studies Vol.28 No.2

Local governments’ use of citizen participation programs is influenced by external environments, especially in the form of political institutions. Local governments decide to expand or limit citizen participation in administrative decision-making processes in response to political uncertainties created by different types of political institutions. Despite the importance of institutional contexts,few studies have examined the effects of these political institutions on the use of citizen participation programs. This study empirically tested whether political institutions affect the adoption of citizen participation programs. The results suggest that the council-manager form of government increases both the adoption of citizen participation mechanisms and the use of citizen participation programs in functional areas, while nonpartisan elections are associated only with the adoption of citizen participation mechanisms. At-large elections show no statistical association with either type of citizen participation. These findings suggest that local political contexts play important roles in the adoption of bureaucratic practices such as citizen participation programs and still support the classical assertion that public administration is closely connected to politics.