Type 347 스테인레스강 용접부의 미세조직 및 파괴기구

오용준,이봉상,류우석,국일현,홍준화 ( Yong Jun Oh,Bong Sang Lee,Woo Seog Ryu,Il Hiun Kuk,Jun Hwa Hong ) 대한금속재료학회 ( 구 대한금속학회 ) 1997 재료강도 심포지엄 Vol.- No.-

이축정렬된 Ni 금속모재에 RF 마그네트론 스퍼터링에 의해 증착된 $CeO_2$ 및 $Y_2O_3$ 완충층 박막 특성

오용준,라정석,이의길,김찬중,Oh, Y.J.,Ra, J.S.,Lee, E.G.,Kim, C.J. 한국초전도학회 2006 Progress in superconductivity Vol.7 No.2

We comparatively studied the epitaxial growth conditions of $CeO_2$ and $Y_2O_3$ thin buffers on textured Ni tapes using rf magnetron sputtering and investigated the feasibility of getting a single mixture layer or sequential layers of $CeO_2$ and $Y_2O_3$ for more simplified buffer architecture. All the buffer layers were first deposited using the reducing gas of $Ar/4%H_2$ and subsequently the reactive gas mixture of Ar and $O_2$, The crystalline quality and biaxial alignment of the films were investigated using X-ray diffraction techniques (${\Theta}-2{\Theta},\;{\phi}\;and\;{\omega}\;scans$, pole figures). The $CeO_2$ single layer exhibited well developed (200) epitaxial growth at the condition of $10%\;O_2$ below an $450^{\circ}C$, but the epitaxial property was decreased with increasing the layer thickness. $Y_2O_3$ seldom showed optimum condition for (400) epitaxial growth. The sequential architecture of $CeO_2/Y_2O_3/CeO_2$ having good epitaxial property was achieved by sputtering at a temperature of $700^{\circ}C$ on the initial $CeO_2$ bottom layer sputtered at $400^{\circ}C$. Cracking of the sputtered buffer layers was seldom observed except the double layer structure of $CeO_2/Y_2O_3$.

내포신도시 개발계획에 대한 주민만족도 평가

오용준(Oh Young June),윤갑식(Yun Kap Sik) 한국지역개발학회 2016 韓國地域開發學會誌 Vol.28 No.1

This research analyzed the effect of the development plan of the Naepo New Town. The Naepo New Town is one of the metropolitan administrative cities, differentiated from the existing cities. To overall identify the intention of the plan, the study analyzed the city development plan rather than the district unit plan. According to the result, first, higher satisfaction for living intention and living environment as the Naepo New Town had a difference from the existing new towns. Second, there was the highest satisfaction for parks and green spaces as well as urban disaster prevention, and it was identified that selfsufficiency and building the living environment was important. Third, among the eight specialization plans for the Naepo New Towns, there was a high satisfaction for public design and parks and green spaces and a low satisfaction for education policy and bicycle path. In addition, the techniques to design the crime preventive environment and specialized university were analyzed as the main project. Lastly, the most important factor that influenced satisfaction for the living environment of the Naepo New Town was infrastructure, followed by land use, parks and green spaces, income, traffic management and occupation. This study is meaningful in that a comparative analysis on the planning elements affecting local residents'satisfaction was empirically conducted by targeting the residents in the Naepo New Town.

소형펀치시험에 의한 연성-취성천이온도 평가 및 국부파괴강도 해석에 의한 표준시험법과 연계성 분석

오용준(Yong Jun Oh),최병찬(Byung Chan Choi),홍준화(Jun Hwa Hong) 대한기계학회 2001 대한기계학회 춘추학술대회 Vol.2001 No.3

Ductile-brittle transition temperatures for the reactor pressure vessel(RPV) steels were determined using a small punch(SP) test and compared to the results from the Charpy impact test and fracture toughness test using a pre-cracked Charpy V-notched(PCVN) specimen in accordance with ASTM E 1921. The correlation between the transition temperatures from the SP test and standard specimen tests was investigated on the theoretical bases regarding the local criteria for cleavage fracture for different specimen geometries and loading conditions. SP test was performed for the seven conventional RPV steels in the temperature range of RT to -196℃. The samples were taken from 1/4T location of the vessels and machined into 10×10×0.5㎜ dimension. SP transition temperature (T<SUB>sp</SUB>) determined at the middle of upper and lower SP energies showed a good correlation with Charpy index temperature, T<SUB>41J</SUB>ㆍFurthermore, it was found that the T<SUB>sp</SUB> had a meaningful correlation with T<SUB>o</SUB> value from the PCVN test. The finite element(FE) calculation for the SP and PCVN test specimens gave a clue to the correlation. Fracture in SP specimen occurred at the highest stress and strain location and the local fracture stress at the cleavage initiation location for SP specimens showed a linear relationship with that for PCVN specimens in the transition region.

세종시 첫마을 지구단위계획에 대한 주민만족도 평가

오용준(Oh, Young-June),홍경구(Hong, Keong-Gu) 대한건축학회 2015 대한건축학회논문집 Vol.31 No.1

This study analyzes the effectiveness of the guideline of the district unit plan that targets the first apartment complexes of Sejong City. To this end, first, this study analyzed residents" satisfaction on the planning elements of the district unit plan of the first apartment complexes through ANOVA test. As a result of the analysis, residents" satisfaction was high in the following order: apartment shape and layout, architecture aesthetic, open spaces in apartment complexes, and environmental design, which are the specialthized planning elements of the district unit plan of the first apartment complexes. This implies that the details of the district unit plan of the first apartment complexes, differentiated from other new towns, affect residents" satisfaction. Second, this study conducted a multiple-regression analysis to draw the district unit plan elements that affect residential satisfaction. According to the analysis result, environmental design, apartment shape and layout, and architecture aesthetic affected residential satisfaction greatly in order. This study is meaningful in that a comparative analysis on the planning elements affecting local residents" satisfaction was empirically conducted by targeting the residents in the first apartment complexes of the Happy City, Sejong.

경수로 원전 가압기 밀림배관의 저주기 피로 수명 및 파괴 특성평가

오용준(Yong Jun Oh),황태복(Tai Bok Hwang) 대한기계학회 2003 대한기계학회 춘추학술대회 Vol.2003 No.8

Low cycle fatigue(LCF) properties of SS 347 and 316N stainless steels used for PWR surgeline piping were evaluated at room temperature and plant operating temperature of 330℃ and the resistance to LCF in the two steels was compared in view of the underlying microstructures. LCF tests were performed for cylindrical round specimens with 8nun-gauge length and 7㎜-outer/4㎜-inner diameters using hydraulic dynamic testing machine. For SS347, thermal-mechanical fatigue properties were additionally evaluated in the temperature range of 100 to 330℃ using the induction heating and air cooling system linked to the LCF test machine. SS316N showed longer fatigue life than SS347 at both of RT and 330℃. Higher test temperature resulted in shorter fatigue life in SS316N while similar fatigue lives in SS347. The similar lives in SS347 were attributed to the different cyclic deformation behavior at RT and 330℃. At room temperature, it was consistently work-hardened throughout the fatigue life while at 330℃ cyclically softened to the end of fatigue life. But, SS316N showed cyclic-softening at both of RT and 330℃. These different cyclic responses only came from the fine NbCN precipitates in the matrix in SS347. From the fractography of the tested samples, we additionally found different crack initiation mechanisms in the two steels. For SS316N, initial fatigue cracks at high input strain range mostly formed intergranularly while at small input strain range the tendency toward transgranular initiation became higher. But SS347 showed intergranular initiation regardless of input strain range.

논문 : Nb 첨가 오스테나이트계 내열 스테인리스강의 열기계적 피로 수명 및 변형 거동

오용준 ( Yong Jun Oh ),박중철 ( Joong Cheul Park ),양원존 ( Won Jon Yang ) 대한금속재료학회(구 대한금속학회) 2011 대한금속·재료학회지 Vol.49 No.7

Thermomechanical fatigue (TMF) behavior of heat resistant austenitic stainless steel was evaluated in the temperature range from 100℃ to peak temperatures of 600 to 800℃; The fatigue lives under TMF conditions were plotted against the plastic strain range and the dissipated energy per cycle. In the expression of the inelastic strain range versus fatigue life, the TMF data obtained at different temperature ranges were located close to a single line with a small deviation; however, when the dissipated energy per cycle, calculated from the area of the stress-strain hysteresis loops at the half of the fatigue life, was plotted against the fatigue life, the data showed greater scattering than the TMF life against the inelastic strain range. A noticeable stress relaxation in the stress-strain hysteresis curve took place at the peak temperatures higher than 700℃, but all specimens in this study exhibited cyclic hardening behavior with TMF cycles. Re-crystallization occurred during the TMF cycle concurrent with the formation of fine subgrains in the re-crystallized region, which is considered to cause the cyclic hardening of the steel.

사회적 약자를 고려한 도시계획요소에 관한 연구

오용준(Oh, Young-June),윤갑식(Yun, Kap-Sik) 한국도시설계학회 2012 도시설계 : 한국도시설계학회지 Vol.13 No.4

사회적 약자를 고려한 도시계획이란 여성과 어린이, 노인 등 도시생활 서비스의 약자가 살기좋은 도시환경을 조성하는 인간도시 차원의 계획을 의미한다. 본 연구는 현재 법정 도시계획기준이 사회적 약자에 친화적인지 분석하고, 선행연구로부터 사회적 약자에 친화적인 계획요소를 도출하여 전문가 의식조사를 통해 이들의 중요도와 적용가능성에 대한 분석과 함께 중점적으로 적용되어야 할 계획위계를 제시하는데 목적이 있다. 연구 결과 첫째, 사회적 약자를 고려한 도시계획 수립의 필요성이 높다고 인식하고 있음에도 불구하고, 기존의 도시계획체계에서는 사회적 약자를 제대로 고려하고 있지 못한 것으로 조사되었다. 둘째, 사회적 약자를 고려한 도시계획요소 중에서 중요도와 적용가능성이 동시에 높은 계획요소는 보행자 안전을 위한 도로 설치, 보도와 차도의 구성체계 구축, 편리하고 안전한 주차시설 설치, 안전한 공원·녹지 조성, 보행자 안전을 위한 가로 시설물 설치 등으로 나타났다. 셋째, 도시계획의 위계가 지구단위계획 수준으로 보다 구체화될수록 사회적 약자를 고려한 계획요소의 중요도와 이의 적용가능성은 높은 것으로 분석되었다. It is widely believed that socially underprivileged groups including women, children, the old, and the physically disabled should be taken into consideration on urban planning in the national land planning and use act. However, the related literature shows that there have been relatively few researches concerning to urban planning factors for socially underprivileged groups. This study aims to analyze the extent of consideration for them on comprehensive city plan, urban management plan, and district unit plan respectively, to draw urban planning factors for them from reviewing previous researches, and to evaluate the importance and the applicability of those factors through the survey focused on professionals. The result shows that there have been lack of attention for socially underprivileged groups in reality, in despite of the high demands for urban planning which allows for them. Also, it is revealed that the importance and the applicability of urban planning factors for socially underprivileged groups are highly recognized. In conclusion, it is suggested that planning factors whose the importance and the applicability are simultaneously significant should be included in urban planning.

공동주택단지 공동체 활성화사업의 효과분석

오용준(Oh, Young-June),윤갑식(Yun, Kap-Sik) 한국지역개발학회 2013 韓國地域開發學會誌 Vol.25 No.2

It is generally recognized that the needs for the sense of community in apartment housing is of great importance. Therefore, various projects for community activation have been implemented by public and private sector. However the literatures show that there have been relatively few empirical research efforts to investigate the impact of the project for community activation in apartment housing on residents" satisfaction. This study aims to analyze the impact of the project on residents" satisfaction through the survey of residents consciousness and to suggest the policy directions for community vitalization based on the result. The impact of the project is investigated in terms of two aspects. One is to examine the change of residents" consciousness concerned to the sense of community prior and posterior to the project. The other is to compare the degree of the sense of community between residents affected or not by the project. The results are as follows. First, the project improved residents" the sense of the community regardless of the resident"s demographic factors. Second, the project encouraged the degree of the residential satisfaction, participation in community activities, and activation of community programs, which means that the more activation of the sense of community, the more satisfaction of residents. Finally, the demand for community programs such as development of community-shared space, improvement of residential environment, and economic cooperative activities are highly recognized by the most of residents.

아두이노 제어 보드와 스마트폰을 활용한 스마트 홈 알람시스템

오용준 ( Yong-jun Oh ),류근호 ( Keun-ho Ryu ) 한국정보처리학회 2014 한국정보처리학회 학술대회논문집 Vol.21 No.2

기존의 알람 어플리케이션은 음향 효과를 통한 자극이라는 단순한 방식으로 과거와 같거나 알람 해 제 방식이 유사한 알람 어플리케이션들이다. 이러한 기존의 방식을 벗어나 알람을 해제하려는 사용자에게 질문을 하고 그에 대한 답변을 Google TTS로 입력받아 알람을 끌 수 있도록 하였다. 또한 알람 종료 시 블루투스 통신을 이용하여 사용자가 입력한 값에 따라 아두이노를 통하여 실내의 조명과 커튼을 제어하여 더 효과적인 알람 효과를 낼 수 있도록 구현하였다.