Carbonization temperature dependent structural modifications of waste coffee grounds derived hard carbons and their electrochemical behaviors as anode materials for sodium ion batteries
JeongA Kim, Donghyeon Yu, Eunchae Oh, Jaewon Jang, Jungpil Kim, Junghoon Yang
Fuzzy probabilistic approximation spaces and their information measures
Qinghua Hu, Donghyeon Yu, Zongxia Xie, Jinfu Liu
IF 11.9
IEEE Transactions on Fuzzy Systems
Rough set theory has proven to be an efficient tool for modeling and reasoning with uncertainty information. By introducing probability into fuzzy approximation space, a theory about fuzzy probabilistic approximation spaces is proposed in this paper, which combines three types of uncertainty: probability, fuzziness, and roughness into a rough set model. We introduce Shannon's entropy to measure information quantity implied in a Pawlak's approximation space, and then present a novel representation of Shannon's entropy with a relation matrix. Based on the modified formulas, some generalizations of the entropy are proposed to calculate the information in a fuzzy approximation space and a fuzzy probabilistic approximation space, respectively. As a result, uniform representations of approximation spaces and their information measures are formed with this work.
A comparative study on deep learning-based anomaly detection models for political news article comments
Youngju Byun, Sang‐Bum Kim, Hyunjin Park, Johan Lim, Kyu S. Hahn, Donghyeon Yu
Journal of the Korean Data and Information Science Society
현대 사회에서 소셜 미디어 및 인터넷 활용이 급속도로 증가함에 따라, 악성 댓글 및 스팸 메일과 같이 정상적인 분포에서 벗어나는 비정상적인 텍스트 데이터가 증가하고 있다. 이러한 문제의 해결을 위해 스팸 메일 및 악성 댓글 등을 식별하기 위한 텍스트 이상치 탐지 및 자연어 처리와 관련된 연구가 활발히 이루어지고 있다. 본 논문에서는 네이버 정치 뉴스 기사 댓글 데이터를 활용하여 딥러닝 기반 모형의 텍스트 이상치 탐지 성능을 비교하였다. 네이어 클린 봇에 의한 검열 정보의 활용 유무에 따라 지도 학습과 비지도 학습 접는 방식을 적용하여 모형의 성능을 비교하였으며, 한국어를 기반으로 사전 학습된 자연어 처리 모형을 활용하여 임베딩 벡터를 산출하였다. 이상치 탐지 성능 비교 결과, 지도 학습 기반 모형에서는 KcELECTRA 임베딩 기반의 FFNN 이진 분류 모형이 가장 우수한 성능을 보였으며, 비지도 학습 기반 모형에서는 KcBERT 임베딩 기반의 Deep SVDD모형이 가장 우수한 성능을 나타내었다.
Carbonization temperature dependent structural modifications of waste coffee grounds derived hard carbons and their electrochemical behaviors as anode materials for sodium ion batteries
JeongA Kim, Donghyeon Yu, Eunchae Oh, Jaewon Jang, Jungpil Kim, Junghoon Yang
Fuzzy probabilistic approximation spaces and their information measures
Qinghua Hu, Donghyeon Yu, Zongxia Xie, Jinfu Liu
IF 11.9
IEEE Transactions on Fuzzy Systems
Rough set theory has proven to be an efficient tool for modeling and reasoning with uncertainty information. By introducing probability into fuzzy approximation space, a theory about fuzzy probabilistic approximation spaces is proposed in this paper, which combines three types of uncertainty: probability, fuzziness, and roughness into a rough set model. We introduce Shannon's entropy to measure information quantity implied in a Pawlak's approximation space, and then present a novel representation of Shannon's entropy with a relation matrix. Based on the modified formulas, some generalizations of the entropy are proposed to calculate the information in a fuzzy approximation space and a fuzzy probabilistic approximation space, respectively. As a result, uniform representations of approximation spaces and their information measures are formed with this work.