Machine learning based Human Activity Recognition with mobile 3-axis magnetometers

Chunghee Nam 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.1

Recently, human activity recognition (HAR) plays an important role in well-being life and context-aware IoT systems. HAR can be carried out in real-time by using sensory data collected from embedded sensor networks in mobile smart phones. Recent HAR investigations have shown that is solely based on 3-axis accelerometers, which is the most energy-efficient approach. In this presentation, I propose a simple approach for HAR process with built-in 3-axis magnetometers in a smart phone. Based on deep learning with convolutional neural network(CNN), I found 98% accuracy for 4 -classes (standing, sitting, jogging, and walking).

The Comfort Women : Japan`s Brutal Regime of Enforced Prostitution in the Second World War

Chunghee Sarah Soh(서평자) The Academy of Korean Studies 1997 Korea Journal Vol.37 No.2

Compartmentalized Gender Schema

Chunghee Sarah Soh The Academy of Korean Studies 1993 Korea Journal Vol.33 No.4

Magnetostatic interaction between magnetic domain walls in dual Co rings

Chunghee Nam 한국물리학회 2016 Current Applied Physics Vol.16 No.7

Magnetostatic interaction of magnetic domain walls (DWs) is investigated by using magnetic force microscopy (MFM) at the remanent state in closely placed Co dual rings. The Co dual rings are 10 and 20 nm in thickness and the spacing between them is varied. In an array of dual rings varying in steps of 10 against the direction of an applied field, the angular dependence of DW interaction shows an obvious change from coupling to decoupling of the DWs in the MFM measurements. It is found that the strong interaction between DWs at smaller angles and smaller spacing is owed to the surface magnetic charge attraction. On the other hand, monopole-like magnetic charge attraction is related with weak DW interaction at higher angles and a larger spacing. In addition, the dependence of the Co thickness on the magnetostatic DW interaction can be explained by the volume magnetic effects.

Machine Learning Directed Prediction of Saturation Magnetization

Chunghee Nam 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.2

Research to predict the various physical properties of inorganic materials using material data has been actively conducted in recent years. Among them, magnetic properties are important features for functional material applications and have been predicted, such as the Curie temperature, coercivity and magnetocaloric properties. In this study, saturation magnetization value was predicted using the DFT quantum calculation-based material data (open source) via machine learning. Ensemble algorithms have been used to compare the performance of models with two metrics of R² (coefficient of determination) and RMSE (root-mean-squared error), as shown in Fig. 1. Detailed results will be presented. 〈그림 본문참조〉

Domain Wall Pinning Strength Tuning in the Planar Submicron-sized Magnetic Y-wire

Chunghee Nam,Youngman Jang,Ki-Su Lee,B. K. Cho 한국자기학회 2007 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Latitudinarian and“Heteroclite”Preacher: Human Nature in Sterne`s Sermons

( Chunghee Kim ) 한국18세기영문학회 2015 18세기영문학 Vol.12 No.1

This paper is an attempt to place Sterne``s sermons within the general context of Sterne``s ethical fluidity as the controlling force of Sterne``s narrative fictions. Although Sterne``s sermons are more or lesscompilations of other divines`` offerings, I argue that they are very specific to him, bearing the marks of his temperament, humor, and social standing. The paper examines Sterne``s sermons in parallel with the sermons which have been identified as Sterne``s sources and confirms that Sterne not only exercises a certain selectiveness but sustains his own particularity. I define Sterne``s particular moral propositions as an ethics of pleasure, which is underlined by a conviction that pleasures can enhance the ethical disposition of man. Sterne is more attuned to the carnal and materialistic aspects of the human condition than most of his sources, accommodating bodily pleasures within the boundary of “innocent pleasures.” I further argue that Sterne, unlike most rationalistic divines, never envisions an ideal world of “universal happiness,” but simply seeks a “world worth living in.” Instead of polarizing reason and animal passions, he contrasts “the bowels of mercy” or “benevolent inclinations” with “unfriendly passions,” trying to promote the former, as he sees innate goodness as quite distinct from rationality. Sterne observes that the tendency to live more to oneself, which grows inproportion with the growth of wisdom, can again be reversed as man enters into the different role of a parent. The “workings of parental kindness,” for Sterne, attests that man is “but an instrument in the hands of God to provide for the well being of others, to serve their interest as well as his own.” This concept of man as “an instrument in the hands of God” is the fundamental basis for Sterne``s ethics of pleasure which expands the domain of innocent pleasures.

Origin and Evolution of Woody Sow-thistles(Sonchus) in the Macaronesian Islands

Chunghee Lee(이정희) 강원대학교 환경연구소 2005 環境硏究 Vol.22 No.-

Determinants of Split Ticket Voting - The Case of South Korea : 한국의 국회의원 선거에서 분할투표의 결정요인 분석 : 17대 총선을 중심으로

LEE Chunghee(이정희),LEE Sangmook(이상묵) 신아시아연구소(구 신아세아질서연구회) 2007 신아세아 Vol.14 No.4

2004년도 국회의원 선거에서 한국의 유권자들은 혼합형 선거구제에서 처음으로 지역구에서의 의원투표와 비례대표에서의 정당투표를 분할해서 투표할 수 있게 되었다. 설문조사에 의하면 한국인 유권자의 약 20%가 분할투표를 한 것으로 나타났다. 그렇다면, 왜 그리고 누가 분할투표를 하였는가? 분할투표의 요인은 무엇이었는가? 본 연구의 목적은 이러한 질문에 대한 답을 구하기 위하여 17대 총선을 중심으로 개인의 선거행태에 초점을 두고 분석하는 것이다. 서구에서의 분할투표에 관한 연구가 많이 있지만 여전히 공통요인에 대한 합의가 형성되어 있지 못하다. 이유는 분할투표의 요인이 나라에 따라 그리고 상황에 따라 다를 수 있기 때문이다. 본 연구에서는 서구에서 검증된 여러 이론적 가설을 한국의 17대 총선에서 검증해보고자 한다. 이를 위한 자료는 17대 총선 이후에 실시된 설문조사를 이용하였다. 본 연구에서의 결론은 당파심이 약하고 정부의 성과에 대한 불만족이 분할투표의 원인이며 또한 진보적인 이념을 가진 사람과 대학생들이 보다 많이 분할투표를 하는 경향이 있다는 것이다. ??In the 2004 National Assembly election, Koreans were first given to cast one vote for a district representative and one vote for a party list under a mixed-member majoritarian system in over five decades. Survey data indicates that about 20 percent of Korean voters split their votes. Why and who did voters split their votes in South Korea? What are the sources of split ticket voting? Although many studies have examined the sources of split ticket voting mainly based on Western democracies, there is little consensus on what causes ticket splitting. It is because motivations for vote splitting vary depending on different contexts. The goal of this study is to find the main sources of split ticket voting in South Korea at the individual level. We test several competing theories of split ticket voting by using election survey data collected immediately after the April 2004 National Assembly election. The findings are that both weak partisanship and low satisfaction with government performance caused split ticket voting in South Korea. Progressives and university students are also more likely to split their votes.

중학교 축구선수들이 지각한 부모의 사회적지지와 자아존중감 및 경기력의 관계

한충희(ChungHee Han),천훙(Hong Chen),김주영(JuYoung Kim),정구인(KooIn Jung) 학습자중심교과교육학회 2019 학습자중심교과교육연구 Vol.19 No.10

본 연구는 중학교 축구선수들이 지각한 부모의 사회적지지와 자아존중감 및 경기력의 관계를 검증하는데 그 목적이 있다. 대한축구협회에 등록된 중학교 남자 축구선수를 연구 참여모집단으로 선정하였으며, 그 중 206명의 중학교 축구선수가 본 연 구의 연구 참여자로 선정되었다. 자료 수집은 2018년 7월 20일에서 7월 31일까지였으며, 자료 분석은 SPSS 21을 이용하여 빈도분석, 확인적 요인분석, 신뢰도분석, 상관 관계분석을 실시하였고, AMOS 21을 이용하여 구조방정식모형 분석을 사용하였 다. 이상과 같은 연구방법과 연구모형 검증을 기초로 본 연구에서 다음과 같은 결과를 도출하였다. 첫째, 중학교 축구선수들이 지각한 부모의 사회적지지가 자아존중감에 영향을 미치는 것으로 나타났다. 둘째, 중학교 축구선수들이 지각한 부모의 사회적지지가 경기력에 영향을 미치지 않는 것으로 나타났다. 셋째, 중학교 축구선수들의 자아존중감이 경기력에 영향을 미치는 것으로 나타났다. The objective of this study was to empirically find out middle school soccer players’ difference by figuring out difference in grade and career by general feature and relationship among parental support, self-esteem and athletic performance in order to verify mediator effect of self-esteem in relationship between parental support and athletic performance perceived by middle school soccer player. The subjects of analysis were middle school soccer players who are registered in Korea Football Association. We distributed questionnaire to 210 middle school soccer players who are in Seoul, Cheonan, and Pohang and used 206 survey result which is valid. To analyze result, frequency analysis, confirmatory factor analysis, reliability analysis, and correlation analysis were conducted by using SPSS 21. And structural equation model analysis was conducted by using AMOS 21. Based on those analytical methods and models, we drew following conclusions. First, it was shown that parental support has an effect on middle school soccer player’s self-esteem. Second, parental support did not have effect on middle school soccer player’s athletic performance. Third, middle school soccer player’s self-esteem had effect on athletic performance. Fourth, parental support did not have direct effect on athletic performance of middle school soccer player, but had indirect effect on athletic performance through a medium which is self-esteem. Seeing this study result, we could conclude that parental support has indirect effect rather than direct one on athletic performance through self-esteem, which is mediating factor. So, it implies that raising self-esteem can be effective to improve middle school soccer player’s athletic performance. Based on this study result, we suggested way for related further studies.