著者
YUTAKA KUNIMATSU YOSHIHIRO SAWADA TETSUYA SAKAI MOTOTAKA SANEYOSHI HIDEO NAKAYA AYUMI YAMAMOTO MASATO NAKATSUKASA
出版者
The Anthropological Society of Nippon
雑誌
Anthropological Science (ISSN:09187960)
巻号頁・発行日
vol.125, no.2, pp.45-51, 2017 (Released:2017-09-21)
参考文献数
58
被引用文献数
2

The African primate fossil record is very poor between the mid-Middle and mid-Late Miocene. Nakali (~10–9.8 Ma) is one of the rare African localities that have yielded primate fossils from this period, including a new genus of great ape, Nakalipithecus nakayamai, and another large-bodied hominoid species. The Nakali primate fauna also includes small-bodied ‘apes’ and Old World monkeys (mostly colobines). In this article, we describe a new specimen of a small-bodied ‘ape’ discovered from Nakali, which is assigned to nyanzapithecines. Nyanzapithecines are characterized by their derived dental morphology, and the previously known nyanzapithecines range in chronological age between the Late Oligocene and early Middle Miocene (~25–13.7 Ma). The new nyanzapithecine specimen from Nakali is therefore the latest occurrence of this group in the African fossil record, extending its chronological range by almost 4 million years younger.
著者
YUTAKA KUNIMATSU YOSHIHIRO SAWADA TETSUYA SAKAI MOTOTAKA SANEYOSHI HIDEO NAKAYA AYUMI YAMAMOTO MASATO NAKATSUKASA
出版者
The Anthropological Society of Nippon
雑誌
Anthropological Science (ISSN:09187960)
巻号頁・発行日
pp.170126, (Released:2017-04-29)
被引用文献数
2

The African primate fossil record is very poor between the mid-Middle and mid-Late Miocene. Nakali (~10–9.8 Ma) is one of the rare African localities that have yielded primate fossils from this period, including a new genus of great ape, Nakalipithecus nakayamai, and another large-bodied hominoid species. The Nakali primate fauna also includes small-bodied ‘apes’ and Old World monkeys (mostly colobines). In this article, we describe a new specimen of a small-bodied ‘ape’ discovered from Nakali, which is assigned to nyanzapithecines. Nyanzapithecines are characterized by their derived dental morphology, and the previously known nyanzapithecines range in chronological age between the Late Oligocene and early Middle Miocene (~25–13.7 Ma). The new nyanzapithecine specimen from Nakali is therefore the latest occurrence of this group in the African fossil record, extending its chronological range by almost 4 million years younger.
著者
Takehisa Tsubamoto Kunimatsu Yutaka Hideo Nakaya Tetsuya Sakai Mototaka Saneyoshi Emma Mbua Masato Nakatsukasa
出版者
The Geological Society of Japan
雑誌
地質学雑誌 (ISSN:00167630)
巻号頁・発行日
vol.121, no.4, pp.153-159, 2015-04-15 (Released:2015-07-29)
参考文献数
20
被引用文献数
1 9

New dental and astragalar specimens of a primitive hippopotamus, Kenyapotamus coryndonae (Mammalia, Cetartiodactyla, Hippopotamidae, Kenyapotaminae) from the lower Upper Miocene Nakali Formation at the Nakali locality, central Kenya, are described and illustrated. The new specimens increase the known morphological and size variations of the dentition and astragalus in this primitive hippopotamid species, which is important to understand the origin and early evolution of the Hippopotamidae.
著者
Zhaohao Zeng Ruihua Song Pingping Lin Tetsuya Sakai
出版者
Information Processing Society of Japan
雑誌
Journal of Information Processing (ISSN:18826652)
巻号頁・発行日
vol.27, pp.742-751, 2019 (Released:2019-11-15)
参考文献数
37

We tackle Attitude Detection, which we define as the task of extracting the replier's attitude, i.e., a target-polarity pair, from a given one-round conversation. While previous studies considered Target Extraction and Polarity Classification separately, we regard them as subtasks of Attitude Detection. Our experimental results show that treating the two subtasks independently is not the optimal solution for Attitude Detection, as achieving high performance in each subtask is not sufficient for obtaining correct target-polarity pairs. Our jointly trained model AD-NET substantially outperforms the separately trained models by alleviating the target-polarity mismatch problem. By employing pointer networks to consider the target extraction task a boundary prediction problem instead of a sequence labelling problem, the model obtained better performance and faster training/inference than LSTM and LSTM-CRF based models. Moreover, we proposed a method utilising the attitude detection model to improve retrieval-based chatbots by re-ranking the response candidates with attitude features. Human evaluation indicates that with attitude detection integrated, the new responses to the sampled queries are statistically significantly more consistent, coherent, engaging and informative than the original ones obtained from a commercial chatbot.