전자재료에 응용되는 공정조성 Solders 의 크리프 강도

이성민 대한금속재료학회(대한금속학회) 1994 대한금속·재료학회지 Vol.32 No.8

In view of the importance of Pb-Sn eutectic alloy in soldered interconnection, the creep phenomena in eutectic bulk solders with microstructures similar to the solder joints have been investigated. A variety of loading paths (tensile, fatigue, load relaxation, and creep) along with microstructural examination were employed to characterize constitutieve behavior and identify potential creep mechanisms(e.g. grain boundary sliding) that might have an impact on fatigue. The experimental work was directed as a clearer description of what some of these phenomena might actually be and how they might be related to the underlying creep mechanisms. The mechanisms of grain boundary sliding and creep strengthening in a wavy eutectic alloy were proposed and the creep strength can be explained based on the stabilized subgrain boundaries caused by the two-phase microstructure.

UFC VoIP의 설계 및 구현

이성민,성동수,이건배 京機大學校 2006 論文集 Vol.50 No.-

This thesis designs and implements SIP UA which is suitable to an embedded system and loads an realtime operating system in order to consider portability. It is based on IETF RFC 3261 standards and is used for UFC. A common human being in ubiquitous environments wears the computer like cloths and gets all information through the network in the near future whenever he walks in the street, takes a rest in the park and runs by car. The effort to implement these future appearance at the present time results in UFC which is one of "wearable computer". For a cooperative task among people wearing UFC, we need the exchange of multimedia information. MoIP is the technique to preform these functions. The standards to implement MoIP are SIP of IETF and H.323 of TTU-T, and the former is predicted to be used much more. If we use SIP UA designed and implemented in the thesis, we can exchange voice and image data among users with wearing UFC in wireless environments as well as between general computers and users with wearing UFC.

스페이스프레임에 사용되는 에너지 흡수형 볼트의 인장성능연구

이성민,김민숙,최정삼,강창훈,Lee, Sung-Min,Kim, Min-Sook,Choi, Jung-Sam,Kang, Chang-Hoon 한국공간구조학회 2007 한국공간구조학회지 Vol.7 No.6

스페이스프레임의 볼 조인트 접합부에서는 축부에 핀의 삽입을 위한 구멍이 존재하기 때문에 응력집중으로 인한 취성파단의 우려가 있다. 따라서 접합부에서의 변형능력이나 에너지흡수능력은 낮은 편이다. 본 연구에서는 볼 조인트 접합부의 소성변형능력을 향상시키기고 현장에서 발생할 수 있는 시공오차의 흡수가 가능하도록, 볼트의 나사부나 핀부의 취성파단 없이 감소된 축부에서 소성변형능력이 기대되는 새로운 접합상세를 개발하였으며 수치해석과 실험을 통해 그 성능을 검증하고자 하였다. 수치해석과 실험을 통하여 볼트의 축부 및 핀부의 단면을 조절함으로써 기존 고력볼트보다 소성변형능력이 향상됨을 확인할 수 있었다. The hole for the insertion of the pin in the shank is exist at ball joint connection of the space frame. It brings about the brittle fracture caused by stress concentration. Consequently it cannot expect the deformation performance or energy absorption performance from ball joint connection. In this study we developed a new connection details which will increase the plastic deformation performance at ball joint connection and can absorb the error in construction, which expect the plastic deformation performance at the reduced shank without brittle fracture at the screw of bolt and pin. Also it's capacity is verified by the performance in numerical analysis and test. We confirmed bolt's plastic deformantion performance through controled shank and pin's area.

방사선치료용 열가소성 플라스틱 마스크의 산란선 감소를 위한 마스크 변형에 관한 연구

이성민,이준영,김재현,정경환,서정민 한국방사선학회 2023 한국방사선학회 논문지 Vol.17 No.1

두·경부 방사선치료에서 환자자세 고정과 재현성을 위하여 사용하는 열가소성플라스틱 마스크는 피부와 밀착되어 산란선을 유발한다. 고정용구 마스크에서 발생되는 산란선으로 인한 피부선량의 증가를 확인하기 위하여 고정용구의 피부밀착 부위를 감소시킴에 따른 산란선의 감소를 CT 스캔한 이미지를 이용하여 전산화치료계획 시스템을 통해 확인하였다. 또한 고정용구의 커버 부위 감소에 따른 셋업의 재현성문제를 확인하기 위하여 DRR과 CT영상을 이용하여 셋업의 차이를 확인하였다. 고정용구로 커버하는 부위를 감소시킴에 따라 피부표면의 선량은 유의하게 감소하였으며 얼굴 전체를 커버하여 고정하지 않아도 재현성에 재현성에 큰 차이가 없음을 확인하였다.

Application of Paris’s Law to Thermal Cycling-Induced Failure in Semiconductor Device Patterns

이성민 대한금속·재료학회 2008 METALS AND MATERIALS International Vol.14 No.6

The present work provides a semi-empirical model to show that the growth rate of thermal displacementinduced cracks in semiconductor devices depends on pattern thickness. Paris’s law is adopted to characterize the growth rate of cracks during thermal-cycling. The crack propagation rate is estimated from the semi-empirical relation (dc/dN)v =C(ΔK) n , where ΔK indicates the range of an applied stress intensity factor, and C is a scaling constant. The applied stress intensity factor is related to the initial crack length as ΔK=YΔσ(πc) 1/2 , where σ represents the thermal displacement-induced normal stress, c describes the pre-existing crack length, and Y is a geometrical factor. The resulting crack growth rate can be expressed as a function of device pattern thickness: dc/dN∝(1/t) m , where t describes the pattern thickness, and m is another constant. The present semi-empirical results showing the relationship between the crack growth rate and pattern thickness indicate that if a semiconductor device pattern becomes thinner by 68 %, its susceptibility to thermal cycling-induced damage will be enhanced by 76 %. The present work provides a semi-empirical model to show that the growth rate of thermal displacementinduced cracks in semiconductor devices depends on pattern thickness. Paris’s law is adopted to characterize the growth rate of cracks during thermal-cycling. The crack propagation rate is estimated from the semi-empirical relation (dc/dN)v =C(ΔK) n , where ΔK indicates the range of an applied stress intensity factor, and C is a scaling constant. The applied stress intensity factor is related to the initial crack length as ΔK=YΔσ(πc) 1/2 , where σ represents the thermal displacement-induced normal stress, c describes the pre-existing crack length, and Y is a geometrical factor. The resulting crack growth rate can be expressed as a function of device pattern thickness: dc/dN∝(1/t) m , where t describes the pattern thickness, and m is another constant. The present semi-empirical results showing the relationship between the crack growth rate and pattern thickness indicate that if a semiconductor device pattern becomes thinner by 68 %, its susceptibility to thermal cycling-induced damage will be enhanced by 76 %.

Coevolution Models with Dynamically Changing Mutation Partners

이성민,Yup Kim 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.II

We study a modified Bak-Sneppen model with dynamically changing mutation partners. Each site on a one-dimensional lattice has a fitness value fi. In a unit update, the site which has the minimum fitness value fmin is selected. Then the selected site and the sites within a distance l from the selected site are updated to new random values. The distance l is stochastically chosen from a power-law distribution P(l) l.μ. We measure the critical fitness and the avalanche distribution in stationary states. For μ < 2, the critical fitness value satisfies the power law fc(N) N.. For μ > 2, fc is finite and approaches the one-dimensional value as μ ! 1. Logarithmic behavior is shown at μ = 2. The avalanche distribution satisfies a normal power law P(s) s. . For μ 2, the exponent ’s have the same value 1.66 within the error bar. However, with increasing μ the avalanche exponent is continuously varying for μ > 2 and approaches the exponent of the onedimensional BS model. We also study the dynamical network structures developed by the present coevolution model.?劑맰

"한 책의 사람(homo unius libri)"의 설교

이성민 감리교신학대학교 2011 신학과세계 Vol.- No.72

자기적 방법을 이용한 비접촉 탄속측정 장치제작

이성민,유일선,김정윤,신준규,정규체,유권상,손대락 한국자기학회 2012 한국자기학회 학술연구발표회 논문개요집 Vol.2012 No.5

렘 쿨하스의 쿤스트할 전시공간의 비정형성에 관한 연구

이성민,윤재은 대한전시디자인학회 2006 전시디자인연구 Vol.3 No.1

Many de-constructionist architects who have pursued the poststructuralist paradigm have interpreted the program through the paradigm of new architecture, from the abandonment of typical and homogeneous architectural form since the Post Modernism. Rem Koolhaas has been one of the representative architects who has interpreted the program anew and reflected it to his design. In terms of the method, this study attempted to analyze the characteristics of atypical expressions shown in the exhibition space of Kunsthal as a formative element through the on-the-spot survey. In order to perform this study, the following should be done: first, one has to understand the theoretical concept of architectural language and philosophical background of Rem Koolhaas and to examine the place of Kunsthal and atypicality of the space, second, in order to analyze the exhibition space of Kunsthal, it would be necessary to analyze the land and place, establishment and atypicality, the spatial circulation and continuity of Kunsthal's design concept 'continuous circuit', and third, it would be necessary to examine the formative characteristics of atypical elements by analyzing the correlation between external and internal formative elements of Kunsthal

2015 개정 교육과정 중학교 기술⋅가정 교과서 ‘인간발달과 가족’ 영역에 반영된 다문화교육 내용 분석

이성민,유난숙 한국가정과교육학회 2019 한국가정과교육학회지 Vol.31 No.2

본 연구의 목적은 2015 개정 교육과정 중학교 기술⋅가정교과서의 ‘인간발달과 가족’ 영역에서 다문화교육 내용이 어떻게반영되고 있는지 분석개념별로 분석하는 데 있으며, 연구 결과는 다음과 같다. 첫째, 2015 개정교육과정 중학교 기술⋅가정교과서5종(총 10권)에 실린 다문화교육 내용을 종합해 보면, 정체성, 다양성, 평등성, 협력 등 다문화교육 분석개념 4가지를 모두 반영하고 있었다. 가장 높은 빈도를 보이는 것은 협력이며, 그 다음이 정체성, 다양성의 순서였고, 평등성에 대한 내용은 가장 낮은빈도를 나타내고 있었다. 둘째, 2015 개정교육과정 중학교 기술⋅가정교과서 5종(총 10권)에 실린 다문화교육 내용을 구체적으로살펴보면 자아 및 정체성을 형성하고, 다양한 관점에서 가족의 변화를 이해하고 다양한 가족의 형태를 존중하고 수용하며, 편견 없는 양성 평등한 관점에서 가족 공동체 문화를 형성하여 궁극적으로 개인과 가정이 서로 협력하고 배려하면서 모두가공존할 수 있는 내용을 배울 수 있도록 다문화교육 내용이 본문, 시각자료, 학습활동에 포함되어 있었다. 따라서 가정교과는다문화 청소년의 삶과 연계된 내용을 중심으로 실천적 문제를 해결할 수 있도록 실천적 추론을 할 수 있는 내용 구성으로이루어져 보다 성숙한 다문화교육 문화에 중추적인 역할을 기여해야 한다. The purpose of this research study was to examine how multi-cultural education contents are reflected in the contents related to the 'Human Development and Family' area of middle school Technology-Home Economics textbooks, based on the multi-cultural education criteria developed by Paek(2014). The sample of the study consisted of the 'Human Development and Family' contents in ‘Technology-Home Economics 1⋅2’ textbooks from five publishers (10 volumes) written in accordance with the 2015 revised curriculum. The research results of the study can be summarized as follows: First, all the four multi-cultural education criterion components were shown in the textbooks from five publishers. Cooperation was shown in the highest frequency, followed by Identity, Diversity, and Equality. Second, the analyses of text, image, and learning activities in the textbooks confirmed that Home Economics as a subject contains multi-cultural education contents that allow students to establish self and identity, respect others, accept diverse family patterns, understand family changes from multiple viewpoints, and form family community culture from gender equality perspective without prejudice. Ultimately, it can be concluded that Home Economics is a subject that enables learners to learn how individuals and families can cooperate and care for each other in order to harmoniously coexist.