著者
井口 亮 水山 克 頼末 武史 藤田 喜久
出版者
日本動物分類学会
雑誌
タクサ:日本動物分類学会誌 (ISSN:13422367)
巻号頁・発行日
vol.46, pp.28-33, 2019-02-28 (Released:2019-03-23)
参考文献数
23

In the submarine caves of the Ryukyu Islands, the existence of many non-described species has been indicated in field surveys. To estimate the magnitude of biodiversity in the submarine caves, application of genetic analyses would provide a promising approach. Genetic analysis by DNA barcoding based on mitochondrial cytochrome c oxidase subunit I (COI) is informative for the study of submarine caves because the data of COI region have been accumulated in many marine animals. Also, in order to understand the formation process of communities of submarine caves, population genetic approaches would be useful to evaluate the connectivity patterns among submarine caves which are not continuously distributed along the Ryukyu Islands. In addition, utilization of high-throughput sequencing technology (e.g., environmental DNA (eDNA) analysis) would be also powerful for the ecological studies of submarine caves of the Ryukyu Islands. We discuss the current situation of genetic analyses in the submarine caves of the Ryukyu Islands and propose the prospects of genetic analyses for future studies.
著者
浦田 健作 中井 達郎 木村 颯 藤田 喜久
出版者
沖縄地理学会
雑誌
沖縄地理 (ISSN:09166084)
巻号頁・発行日
vol.21, pp.55-71, 2021 (Released:2021-08-02)

沖縄県名護市辺野古崎沖の長島で鍾乳洞を確認し,調査を実施した.その結果以下のことが明らかとなった.①本洞には多様な石灰質洞窟生成物(鍾乳石)が発達しており,これまで報告されていない地形である「固結礫塔」や洞内では稀であるビーチロック類似層が確認された.②本洞は,カルスト作用,波浪作用,生物作用によって形成された洞窟であり,「海岸カルスト」というべき地形である.③洞口付近の微光帯には傾光性をもつ光カルスト地形(光鍾乳石と光カレン)がよく発達しており,亜熱帯海岸カルストの特徴と考えられる.④洞内では人為的影響を受けた痕跡はほとんど認められず,極めて良好な保存状態にある.⑤本洞の空洞形成の状況から,島の面積をはるかに越える集水域に涵養された地下川洞窟の一部であることが考えられ,長島周辺の(サンゴ礁)海域に“失われた石灰岩台地”の存在が示唆される.以上のことから,長島の鍾乳洞(“長島鍾乳洞”と命名する)は,学術的にもまた地域社会の資源としても価値が高いため今後速やかに保全策を講じる必要がある.
著者
橘 智也 正田 浩暉 Aiza Syamimi Binti Abd Rani 野間口 大 岡本 和也 藤田 喜久雄
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
pp.21-00222, (Released:2022-01-07)
参考文献数
21
被引用文献数
1

Generating novel design concepts in the conceptual design phase is a cornerstone for producing innovative products. This paper proposes a method to support the generation of new design concepts from patent documents. The proposed method is based on the theory of novelty potential that the combination of abstract concepts leads to the generation of the novel design concept and that the distance between the combined abstract concepts correlates to the possibility of generating it. This research adopts the distributed word representation model of word2vec to extract abstract concepts from patent documents and to measure the concept distance. The two matrices are introduced to visualize the relationships of the extracted abstract concepts; the novelty potential matrix which shows the value of the novelty potential between the abstract concepts, and the void matrix which shows the numbers of existing patents of the abstract concepts. They help a designer to identify the combinations of abstract concepts that are high novelty potential and no existing patent. This paper demonstrates a case study of generating novel ideas of sports business with blockchain using the proposed method. The results show its uniqueness and effectiveness.
著者
藤田 喜久 下村 通誉 東 和明
出版者
Pro Natura Foundation Japan
雑誌
自然保護助成基金助成成果報告書 (ISSN:24320943)
巻号頁・発行日
vol.30, pp.49-56, 2021-09-30 (Released:2021-09-30)
参考文献数
14

南大東島の洞窟地下水においてダイトウコオイエビ Halosbaena daitoensis Shimomura and Fujita, 2009の生息状況と生態に関する研究を行なった.本研究期間中に南大東島の計13箇所の洞窟(16調査地点)の地下水域にて調査を行った結果,5洞窟(計8調査地点)にて本種の生息が確認された.これらの調査地点のうち,本研究で新たにダイトウコオイエビの生息が確認された洞窟地下水は,4洞窟(7調査地点)であり,本種の分布は南大東島の北部と南部の広範囲に点在する洞穴地下水域に及ぶことが明らかとなった.また,ダイトウコオイエビの生態を明らかにするため,2019年12月~2020年11月までの毎月,南大東島北東部に位置する“洞窟A”において採集調査を実施し,当該洞窟において本種の生息が周年確認できることが明らかとなった.しかしながら,本種の抱卵個体を得ることはできず,本種の繁殖生態については未だ不明である.
著者
藤田 喜久 佐伯 智史 仲吉 将一 福島 新 成瀬 貫
出版者
日本甲殻類学会
雑誌
CANCER (ISSN:09181989)
巻号頁・発行日
vol.30, pp.11-19, 2021-08-01 (Released:2021-08-26)
参考文献数
12

An endangered freshwater crab, Ryukyum yaeyamense (Minei, 1973) (Crustacea: Decapoda: Brachyura: Potamidae), is recorded for the first time from Kohamajima Island, Yaeyama island group, southern Ryukyu Islands, Japan. Kohamajima Island becomes the third distributional island of the species. The morphological characteristics of the species, their habitats, and ecological notes of the species are provided.
著者
藤田 喜久
出版者
日本甲殻類学会
雑誌
CANCER (ISSN:09181989)
巻号頁・発行日
vol.19, pp.41-51, 2010-05-01 (Released:2017-07-05)
参考文献数
33
著者
濱田 宏 木村 健一 遠藤 恵美子 福井 明 藤田 喜久 高折 益彦
出版者
THE JAPAN SOCIETY FOR CLINICAL ANESTHESIA
雑誌
日本臨床麻酔学会誌 (ISSN:02854945)
巻号頁・発行日
vol.11, no.4, pp.471-479, 1991-07-15 (Released:2008-12-11)
参考文献数
23

局所麻酔薬に添加した血管収縮薬が脊椎麻酔の持続時間に及ぼす効果を検討した.下肢の予定手術患者を対象に,ネオペルカミンS単独群(C群),エピネフリン0.1mgおよび0.2mg添加群(E1群,E2群),ノルエピネフリン0.1mg添加群(NE群)に分けた.最高レベルより2椎体,4椎体低下する時間(分)はE1群でそれぞれ平均120分,178分,E2群でそれぞれ145分,191分,NE群でそれぞれ142分,180分で,ともにC群の95分,135分より有意に延長していた.しかし,E1,E2,NE群の間に有意差を認めなかった.NEがEより勝る利点を見出すことはできなかったが,NEの添加でも有意な延長効果を認めた.
著者
野間口 大 中切 拓 藤田 喜久雄
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.83, no.853, pp.17-00122, 2017 (Released:2017-09-25)
参考文献数
22
被引用文献数
4

Generation of new concepts in product design process serves as driving force of innovation. While many methods have been proposed for supporting design concept generation, it has rarely been supported in a systematic way, because its process is done in designer's implicit thought, and therefore, it is difficult to explicitly formalize the process. This paper proposes a model of designers' thinking process in concept generation called ECF cycle. It consists of three steps, i.e., (1) Externalization: the step for representing design concepts with drawings and language, (2) Classification: the step for classifying concepts with function trees, and (3) Finding voids: the step for finding potentials of new concepts called void, which is a defect of the classification. Then, this research builds a new method of concept generation incorporating the theory of solving inventive problems (TRIZ). The method is based on a quick reference table of TRIZ principles, which helps designers to create a new concept corresponding to a void found by ECF cycle. A case study of concept generation of new running shoes is demonstrated in order to verify the ability of the proposed method.
著者
藤田 喜久
出版者
日本動物分類学会
雑誌
タクサ:日本動物分類学会誌 (ISSN:13422367)
巻号頁・発行日
vol.44, pp.15-22, 2018-02-28 (Released:2018-03-20)
参考文献数
43

Recent studies of decapod crustaceans in anchialine and submarine caves of the Ryukyu Islands were reviewed. A total of 10 species, belonging to 7 genera of 5 families, have been recorded in anchialine caves, and all of them are listed on the Red List (List of Endangered and Threatened Species in Japan or Okinawa Prefecture). In the submarine caves, remarkable findings of decapods and other crustaceans are continuing even in recent years. Further “many eyes” will be poured into the submarine caves, it is expected that the characteristics of the animal communities in the Ryukyu Islands will be understood in more detail.
著者
山内 仁史 山﨑 慎太郎 矢地 謙太郎 藤田 喜久雄
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.83, no.855, pp.17-00320-17-00320, 2017 (Released:2017-11-25)
参考文献数
23
被引用文献数
1

Multi-fidelity analysis has been used for reducing the calculation cost of evaluating the design solution, which is the most costly process in design optimization. In general, multi-fidelity analysis is applied to problems with continuous design variables, which are suitable to construct an approximate model of design space such as the response surface. On the other hand, combinatorial optimization problems, e.g., layout design, are difficult to apply the conventional multi-fidelity analysis, since the response surface cannot be constructed due to the property of the design variables. In this paper, we propose a multi-fidelity optimization method independent of the response surface and a simple analysis model for the method, and apply them to multi-disciplinary optimal layout design problem which is a complicated combinatorial optimization problem. The proposed analytical model, which adopts the concept of the explicit method, realizes for reducing the calculation time by simplifying the physical phenomenon. Then, the multi-fidelity optimization method is constructed by combining the proposed analysis model with the thermal network method which is a well-known thermal analysis method. We confirm that there is a strong correlation between the calculation result of the proposed analysis model and of a CAE software, and show that the proposed analysis model is suitable as a low fidelity model. The effectiveness of the proposed optimization method is demonstrated through numerical experiments.
著者
野間口 大 董 春祉 堀之内 貴大 藤田 喜久雄
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.83, no.854, pp.17-00167-17-00167, 2017 (Released:2017-10-25)
参考文献数
18

The product design project includes many uncertainties. It causes risk that a project target cannot be accompolished within lead time. In order to flexibly handle the uncertainty and avoid the risk, adaptive planning that can switch easily to another plan by preparing options for a task is needed. When a challenging design alternative is difficult to be accompolished, a project manager should decide either to continue the design taking a risk or to switch to a conservative alternative disliking a risk. This paper proposes a new optimization-based project planning method that aims at a Pareto-optimal of the potential technical performane of designed product and a project failure risk. A task option model is employed for risk assesment of option-based project management. As its planning includes a number of various design variables and various evaluation indices, in order to solve such a complicated problem with a reasonable computation cost, this research separates the optimization problem into two phases, i.e., (i) defining of process architecture and organization structure and (ii) scheduling of resource allocation into activities. This paper demonstrates its application to a student formula design project. A proposed optimization method facilitates a project manager to explore various process plans with assessing their risks.
著者
藤田 喜久
出版者
日本甲殻類学会
雑誌
CANCER (ISSN:09181989)
巻号頁・発行日
vol.19, pp.41-51, 2010
参考文献数
33
被引用文献数
2
著者
野村 勝也 高橋 篤弘 小島 崇 山崎 慎太郎 矢地 謙太郎 坊 大貴 藤田 喜久雄
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
電子情報通信学会論文誌 B (ISSN:13444697)
巻号頁・発行日
vol.J102-B, no.8, pp.669-673, 2019-08-01

最適な構造物を数値計算で導出する手法であるトポロジー最適化をノイズフィルタの導体パターン設計に適用した.回路定数により支配的なノイズが異なるフィルタで最適化を行った結果,支配的なノイズに応じた構造変化が生じ,フィルタの性能が向上した.
著者
藤田 喜久 佐伯 智史 仲吉 将一 福島 新 成瀬 貫
出版者
日本甲殻類学会
雑誌
CANCER (ISSN:09181989)
巻号頁・発行日
vol.30, pp.11-19, 2021

<p>An endangered freshwater crab, <i>Ryukyum yaeyamense</i> (Minei, 1973) (Crustacea: Decapoda: Brachyura: Potamidae), is recorded for the first time from Kohamajima Island, Yaeyama island group, southern Ryukyu Islands, Japan. Kohamajima Island becomes the third distributional island of the species. The morphological characteristics of the species, their habitats, and ecological notes of the species are provided.</p>