http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Yongxing Li (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Online Hot Topic Detection Based on Segmented Timeline and Aging Theory
Ruiguo Yu,Xiaodong Xie,Yongxing Li,Mankun Zhao,Xuyuan Dong,Muwen He,Peng Chang,Zan Wang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.2
With a great deal of digitized textual information now available on the internet, it is almost impossible for people to assimilate all the information timely. Therefore, the technologies of topic detection and tracking are used for constructing news topics from news stories in order to bring convenience to people. However, traditional topic detection methods are not always so effective in detecting emerging hot news topics in a short period of time, and most topic detection methods use single-pass clustering algorithm which is with low accuracy and very sensitive to the input sequence of news documents. In order to improve clustering accuracy, we utilize a temporal distance factor to segment timeline into equal parts and propose a novel two-times single-pass clustering algorithm to deal with news stories in each part of timeline separately. Moreover, the aging theory is combined with our approach to build life-span model of topics from which we can obtain variation trend of hotness value of topics. The results of experiments show that our approach is effective and the life circle model of topics established by our method can conform to reality well.
-
Yin Qin,Batbatan Christopher G.,Li Yongxing,Zhang Yonghui,Yang Qiuming,Xiao Anfeng 한국미생물·생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.1
In this study, carrageenase immobilization was evaluated with a concise and efficient strategy. Pomelo peel cellulose (PPC) modified by polyethyleneimine (PEI) using the physical absorption method was used as a carrier to immobilize carrageenase and achieved repeated batch catalysis. In addition, various immobilization and reaction parameters were scrutinized to enhance the immobilization efficiency. Under the optimized conditions, the enzyme activity recovery rate was more than 50% and 4.1 times higher than immobilization with non-modified pomelo peels. The optimum temperature and pH of carrageenase after immobilization by PEI-modified pomelo peel, at 60°C and 7.5 respectively, were in line with the free enzyme. The temperature resistance was reduced, inconsistent with free enzyme, and pH resistance was increased. A significant loss of activity (46.8%) was observed after reusing it thrice under optimal reaction conditions. In terms of stability, the immobilized enzyme conserved 76.0% of the initial enzyme activity after 98 days of storage. Furthermore, a modest decrease in the kinetic constant (Km) value was observed, indicating the improved substrate affinity of the immobilized enzyme. Therefore, modified pomelo peel is a verified and promising enzyme immobilization system for the synthesis of inorganic solvents.
KCI
KISS연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
