Corrosion Behavior of Anodized Additively Manufactured Ti-6Al-4V alloy

Kyungbin Ahn,Heejin Jang 한국표면공학회 2023 한국표면공학회 학술발표회 초록집 Vol.2023 No.11-1

Developing Criteria for Evaluating Smartphone Apps for English Teaching and Learning

( Kyungbin Im ) 글로벌영어교육학회(구 호남영어교육학회) 2017 Studies in English education Vol.22 No.1

The purpose of this study is to develop a tool to evaluate application programs (apps) developed for English teaching and learning for smartphones. To do this, several software evaluation tools were analyzed. The research results used for the analysis were the ones in which the evaluation criteria were clearly presented among the accessible papers from the 1980`s, when the researchers create theories in relation to CALL, which is the basis of MALL. All eight papers were selected and analyzed. In the result part of this study, various evaluation criteria were analyzed and comprehensive evaluation criteria were presented, and a web based evaluation method was proposed to increase user convenience. In a follow up study, the evaluation criteria suggested in this study can be tested by the expert group and the user group in order to use the result to revise and improve the evaluation criteria proposed in this study.

Thermal Characteristics of Graphite Foam Thermosyphon for Electronics Cooling

Kyungbin Lim,Hongkoo Roh 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.10

Graphite foams consist of a network of interconnected graphite ligaments and are beginning to be applied to thermal management of electronics. The thermal conductivity of the bulk graphite foam is similar to aluminum, but graphite foam has one-fifth the density of aluminum. This combination of high thermal conductivity and low density results in a specific thermal conductivity about five times higher than that of aluminum, allowing heat to rapidly propagate into the foam. This heat is spread out over the very large surface area within the foam, enabling large amounts of energy to be transferred with relatively low temperature difference. For the purpose of graphite foam thermosyphon design in electronics cooling, various effects such as graphite foam geometry, sub-cooling, working fluid effect, and liquid level were investigated in this study. The best thermal performance was achieved with the large graphite foam, working fluid with the lowest boiling point, a liquid level with the exact height of the graphite foam, and at the lowest sub-cooling temperature.

The Effects of Overseas Volunteer Service Experience on Students’ Attitudes for English Learning ―Focusing on Service Learning

( Kyungbin Im ),( Seohyun Bae ) 글로벌영어교육학회(구 호남영어교육학회) 2018 Studies in English education Vol.23 No.1

The purpose of this study is to investigate the attitudes of students who experienced overseas volunteer service and its influence on attitudes towards English learning and the ways of improving the quality of overseas volunteer service learning program in the future. In previous research results, related to service learning, it has been reported that service learning has a very positive effect not only on the personalities of the students involved in service learning but also on the areas related to subject learning. However, studies on the effects of service learning on English learners’ attitudes are hard to find. In this study, in order to find out the effects of overseas volunteer service on attitudes towards English learning, 41 students who participated in overseas volunteer service were surveyed before and after volunteer activities. The survey results showed that several aspects of the participants’ attitudes toward English learning changed through overseas volunteer service experience. Their interest in English learning has increased, their confidence in their use of English has also increased, and many participants answered that they felt a stronger need for English learning. These changes were statistically significant. However, this study is based on the fact that a small number of people have been selected for research, so more general research will have to be done to generalize it.

<i>In Vivo</i> Estimation of Human Forearm and Wrist Dynamic Properties

Park, Kyungbin,Chang, Pyung-Hun,Kang, Sang Hoon IEEE 2017 IEEE transactions on neural systems and rehabilita Vol.25 No.5

<P>It is important to estimate the 3 degree-of-freedom (DOF) impedance of human forearm and wrist (i.e., forearm prono-supination, and wrist flexion-extension and radial-ulnar deviation) in motor control and in the diagnosis of altered mechanical resistance following stroke. There is, however, a lack of methods to characterize 3 DOF impedance. Thus, we developed a reliable and accurate impedance estimation method, the distal internal model based impedance control (dIMBIC)-based method, to characterize the 3 DOF impedance, including cross-coupled terms between DOFs, for the first time. Its accuracy and reliability were experimentally validated using a robot with substantial nonlinear joint friction. The 3 DOF human forearm and wrist impedance of eight healthy subjects was reliably characterized, and its linear behavior was verified. Thus, the dIMBIC-based method can provide us with 3 DOF forearm and wrist impedance regardless of nonlinear robot joint friction. It is expected that, with the proposed method, the 3 DOF impedance estimation can promotemotor control studies and complement the diagnosis of altered wrist and forearm resistance post-stroke by providing objective impedance estimates, including cross-coupled terms.</P>

불소 첨가/미첨가 인공타액 용액에서 연마 및 마스킹 조건이 적층제조 Ti-6Al-4V 합금의 동전위분극시험 결과에 미치는 영향

안경빈 ( Kyungbin Ahn ),장희진 ( Heejin Jang ) 한국부식방식학회 2021 Corrosion Science and Technology Vol.20 No.6

Additively manufactured titanium alloy is one of the promising materials in advanced medical industries. However, these additively manufactured alloys show corrosion properties different from those of conventional materials due to their unique microstructure. In this study, the effect of surface roughness and masking conditions on the results of the potentiodynamic polarization tests on additively manufactured or conventional Ti-6Al-4V alloys in artificial saliva solution with or without fluoride was investigated. The results showed that the corrosion potential was slightly lower with a flat cell with an O-ring than with masking tape. The corrosion rate was decreased with decreases in the surface roughness. Localized corrosion involving delamination of the surface layer occurred at 7 ~ 9 V (SSC) on the additively manufactured alloy in solution with or without fluoride when the samples were finished with 1000-grit SiC paper, whereas localized corrosion was not observed in the specimens finished with 1-μm alumina paste.

Trends in Education and Polices for Women in Korea : Focusing on Mathematics, Science, and Career Choice

박경빈(Kyungbin Park),문정화(Jeong-hwa Moon),하종덕(Jong Duk Ha) 한국영재학회 2006 영재교육연구 Vol.16 No.2

본 연구는 한국 여성들의 교육과 정책 변화의 흐름을 알아보는 것이다. 먼저 여성 교육에 대한 편견이 깊이 뿌리박혀 있는 한국에서의 여성 교육의 역사적 배경을 살펴보았다. PISA와 TIMSS와 같은 학업성취도 국제 비교 연구와, 국가수준 학업 성취도 연구를 통해 특별히 과학과 수학에서 남녀 학생의 성취 수준의 차이를 알아보았다. 여학생들이 일반적인 학업성취에서는 남학생보다 우수하거나 같았고, 국제 평가에서는 읽기 소양에서는 남학생보다 높은 성취를 보였으나, 수학과 과학에서는 남학생보다 훨씬 낮은 수준이었다. 남여 학생 간의 성취도의 차이는 OECD 회원국 중에서 가장 컸다. 또한 교육 제도와 학업과 직업적 성취를 중심으로 현대사회에서 여성의 위치가 어떻게 변하고 있는지를 조사했다. 더불어 여성 전문가 양성을 지원하는 다양한 계획과 정책에 대해서도 소개했다. 끝으로, 남학생과 여학생의 학업성취 격차에 대한 원인들을 살펴보았고, 수학과 과학의 남녀 학생의 차이를 줄이기 위한 몇 가지 제안을 했다. This study is focused on the trends in education and polices for women in Korea. First, historical background of education for women in Korea revealed that a biased view of education for women was deeply rooted. Next, several findings arch as international comparison of performance on the PISA, TIMSS, and National Assessment induding gender differences especially in Mathematical and Science performance were analyzed. In international assessments, female students perform better in reading literacy, but still fall behind male students in mathematical and scientific literacy, and the gap between the genders are wider than most OECD countries. The change in status of women in contemporary Korea is examined focusing on educational system and women’s educational and vocational performance, etc. Additionally, policies planned by Ministry of Science and Technology which show the many execution plans for training and supporting female professionals were presented. Finally, possible reasons for gender differences in educational performance is examined and some suggestions are provided to reduce the gender gap in mathematical and scientific literacy of Korean students.

The Effects of E-Learning on University Students’ TOEIC Achievement and their Satisfaction

Im, Kyungbin 미래영어영문학회 2021 영어영문학 Vol.26 No.1

This study aims to investigate the effects of E-learning conducted under unavoidable Covid-19 circumstances and the satisfaction of students in class and their achievement, and to establish and suggest future countermeasures in relation to the results. For this study, 89 university students were participated. Two tests and a survey were designed for data collection. The two test results were compared to analyze students’ TOEIC achievement. The survey results were also analyzed to find out the participants’ opinion on the learning experience using E-learning method for TOEIC study. The results showed that students improved their TOEIC achievement in the second test which is statistically meaningful. The survey results showed many aspects of their learning experience. Although there were no negative opinions, there were more positive opinions on E-learning. In addition, some inconvenient points related to E-learning have been found, and improvement measures should be devised in the future.

성공적인 성취자의 심층 면담을 통한 영재교육의 방향성 탐색

박경빈(Kyungbin Park),이재호(Jaeho Lee),박명순(Myungsoon Park),이선영(Sunyoung Lee),전미란(Miran Chun),류지영(Jiyoung Ryu),안성훈(Seonghun Ahn),변순화(Soonhwa Byun) 한국영재학회 2015 영재교육연구 Vol.25 No.2

이 연구는 사회적으로 성공한 인사들의 성취에 영향을 준 요인을 조사하고 영재교육의 개선 방향을 도출하기 위해 수행되었다. 이를 위해 성취자 60명을 대상으로 6개 분야(교육, 전공, 가정 및 부모, 대인관계, 여가시간, 업적 및 성공요인)에 대해 반 구조화된 심층면담을 실시하였 다. 연구 결과 많은 성취자들은 적극적인 학생이었으며, 가정은 화목하고 자율적이었고, 차별화 교육 및 학생 중심의 교육이 중요하다고 생각하였다. 개인적으로는 멘티를 지도하고 있지 않다 는 응답자가 많았다. 전공 결정 및 교육은 재능과 흥미의 발견 시기에 맞춰 이뤄져야 한다고 응답하였다. 여가시간 활동으로는 운동, 음악, 독서를 중요시하였으며, 성취의 원동력이 된 것은 호기심, 자신감 등 개인 내적 특성이었다. 영재교육을 수혜한 성취자들은 영재교육의 경험이 성취에 중요한 영향을 준 것으로 인식하고 있었다. 면담 결과를 영재교육의 개선 방향과 관련지 어 시사점을 논의하였다. The purpose of this study was to investigate factors that affected achievement of socially succeeded people, and to draw ways to improve gifted education. To do this, we interviewed 60 achievers. The interview was administrated as semi-structured deep interview about 6 areas - education, major, family and parent, personal relationship, leisure time activity, achievement and motivation of success. The results showed that achievers were active students during their school days. They thought differentiated education and student-centered lessons are important. Many achievers answered they do not have any personal mentee, and decision of majors and education should be matched with the perception of one's potential and interest. Exercises, music, and reading books were strongly suggested as leisure time activities, and the key inner factors for success were curiosity and self-confidence. Beneficiaries of gifted education perceived their experience of gifted education had a positive influence on their achievement. Based on the these results, ways to improve gifted education were discussed.

메타버스를 이용한 영어학습을 위한 메타버스 플랫폼 비교분석

임경빈(Im, Kyungbin) 미래영어영문학회 2023 영어영문학 Vol.28 No.2