著者
Yuichiro Kobayashi Misaki Amagasa Takafumi Suzuki
出版者
日本デジタル・ヒューマニティーズ学会
雑誌
Journal of the Japanese Association for Digital Humanities (ISSN:21887276)
巻号頁・発行日
vol.2, no.1, pp.90-107, 2017-09-06 (Released:2017-09-07)
参考文献数
29

Popular songs can be regarded as a fine representation of modern society andculture. In particular, the lyrics of popular songs are the most importantaspect for understanding the sense of values and linguistic sensitivity in agiven generation and community. The purpose of the present study is toinvestigate the chronological variation of popular Japanese songs usingstylometric techniques. This study draws on the lyrics of 858 songs, whichappeared on the Oricon annual top 20 single hit chart between 1976 and 2015. Thelinguistic features investigated in this study include five different types oflexical indices, namely (a) number of words, (b) parts-of-speech, (c) wordtypes, (d) character types, and (e) vocabulary level. Multiple regressionanalysis was conducted to explore the chronological change in the frequencies oflexical indices. The results showed that the frequencies of word types andcharacter types dramatically changed before and after 1990. Moreover, the usagesof auxiliary verbs as well as lower level vocabulary became more prominent,whereas the frequencies of adjectival nouns and conjunctions decreased. Thefindings suggest that a turning point in cultural trends corresponds with thehistorically significant political and economic events, such as the end of theShowa era and the burst of the bubble economy.
著者
Yui Arakawa Ryosuke Yoshimoto Fuyuki Yoshikane Takafumi Suzuki
出版者
日本デジタル・ヒューマニティーズ学会
雑誌
Journal of the Japanese Association for Digital Humanities (ISSN:21887276)
巻号頁・発行日
vol.1, no.1, pp.1-9, 2015-09-02 (Released:2015-09-02)
参考文献数
13

Gathering information from social media content is becoming increasingly popular. Twitter, a microblog where posts are limited to 140 characters, is an excellent platform for gathering instant and interactive information. Considerable research has focused on Twitter’s effectiveness for disseminating emergency alerts and confirming the safety of acquaintances. However, there has been less emphasis on the analysis of Twitter posts to obtain information specialized to specific domains. Such analysis could enable simple and rapid identification of information related to state-of-the-art technology. Against this background, this study reports on a preliminary analysis of tweets by Japanese academic researchers. Our content analysis and text analysis reveal that many academic researchers tweet about their individual activities, education, or research. Their tweets contain domain-specific knowledge and have identifiable textual characteristics. This study provides basic findings that can be applied to obtain domain-specific knowledge from Twitter.
著者
Masayuki HIRATA Kojiro MATSUSHITA Takafumi SUZUKI Takeshi YOSHIDA Fumihiro SATO Shayne MORRIS Takufumi YANAGISAWA Tetsu GOTO Mitsuo KAWATO Toshiki YOSHIMINE
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E94-B, no.9, pp.2448-2453, 2011-09-01

The brain-machine interface (BMI) is a new method for man-machine interface, which enables us to control machines and to communicate with others, without input devices but directly using brain signals. Previously, we successfully developed a real time control system for operating a robot arm using brain-machine interfaces based on the brain surface electrodes, with the purpose of restoring motor and communication functions in severely disabled people such as amyotrophic lateral sclerosis patients. A fully-implantable wireless system is indispensable for the clinical application of invasive BMI in order to reduce the risk of infection. This system includes many new technologies such as two 64-channel integrated analog amplifier chips, a Bluetooth wireless data transfer circuit, a wirelessly rechargeable battery, 3 dimensional tissue-fitting high density electrodes, a titanium head casing, and a fluorine polymer body casing. This paper describes key features of the first prototype of the BMI system for clinical application.
著者
Takafumi SUZUKI Naohito NISHII Satoshi TAKASHIMA Tatsuya MATSUBARA Atsushi IWASAWA Hirofumi TAKEUCHI Kohei TAHARA Tatsuyuki HACHISU Hitoshi KITAGAWA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
(Released:2015-06-09)

Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for insulin and their epitopes. Following the passing of fraction A, which did not bind to insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis (Biacore™system), were 1.64e−4 M for fraction B (low affinity IgGs) and 2e−5 M for fraction C (high affinity IgGs). Epitope analysis was conducted using 16 peptide fragments synthesized in concord with the amino acid sequence of feline insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher absorbance (affinity) of the peptide fragment of 10 amino acid residues at the carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to 15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding IgGs are multifocal and may be composed of multiple IgG components and insulin.