著者
Yoshinori IIZUKA(飯塚芳徳) Sumito MATOBA(的場澄人) Masahiro MINOWA(箕輪昌紘) Tetsuhide YAMASAKI(山崎哲秀) Kaoru KAWAKAMI(川上薫) Ayako KAKUGO(角五綾子) Morihiro MIYAHARA(宮原盛厚) Akihiro HASHIMOTO(橋本明弘) Masashi NIWANO(庭野匡思) Tomonori TANIKAWA(谷川朋範) Koji FUJITA(藤田耕史) Teruo AOKI(青木輝夫)
出版者
THE JAPANESE SOCIETY OF SNOW AND ICE
雑誌
Bulletin of Glaciological Research (ISSN:13453807)
巻号頁・発行日
vol.39, pp.1-12, 2021 (Released:2021-10-13)
参考文献数
18
被引用文献数
1

In order to construct reliable deposited-aerosol database on the Anthropocene (from 1850 to 2020), we obtained a 250-meter-long ice core from the Southeastern Greenland Dome on May and June 2021, where is one of the highest accumulation domes in Greenland. The age of the ice core at a depth of 250 m was roughly estimated to be AD 1827 based on the timescale from a previously analyzed shallower ice core. The age of the sampled ice core satisfied the prerequisite conditions for constructing aerosol deposition database for Anthropocene. In addition, surface elevation, borehole temperatures, and internal stratigraphy of the ice sheet were performed, and meteorological and snow-pit observations were also conducted. Furthermore, we sampled aerosol and snow from the ice sheet for chemical and physical analyses.
著者
Akihiro Hashimoto Hiroki Motoyoshi Narihiro Orikasa Ryohei Misumi
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.16, pp.51-56, 2020 (Released:2020-03-25)
参考文献数
36

We have developed a new method of diagnosing the characteristics of ice particles using a bulk microphysics model. Our model tracked the mass compositions of different classes of ice particles, using their microphysical process of origin, such as water vapor deposition and riming. The mass composition from depositional growth was further divided into six components by the temperature and humidity ranges corresponding to the typical growth habits of ice crystals. In test simulations, the new framework successfully revealed the influences of riming and depositional growths of ice particles within clouds and on surface snowfall. The new approach enables weather prediction models to provide much more information on the characteristics of ice particles regarding crystal habits and the extent of riming.
著者
Akihiro Hashimoto Hiroki Motoyoshi Narihiro Orikasa Ryohei Misumi
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2020-009, (Released:2020-03-02)

We have developed a new method of diagnosing the characteristics of ice particles using a bulk microphysics model. Our model tracked the mass compositions of different classes of ice particles, using their microphysical process of origin, such as water vapor deposition and riming. The mass composition from depositional growth was further divided into six components by the temperature and humidity ranges corresponding to the typical growth habits of ice crystals. In test simulations, the new framework successfully revealed the influences of riming and depositional growths of ice particles within clouds and on surface snowfall. The new approach enables weather prediction models to provide much more information on the characteristics of ice particles regarding crystal habits and the extent of riming.
著者
AARONJ.STOKES HIDEO MATSUDA AKIHIRO HASHIMOTO
雑誌
情報処理学会論文誌データベース(TOD) (ISSN:18827799)
巻号頁・発行日
vol.40, no.SIG06(TOD3), pp.66-78, 1999-08-15

Complete DNA sequences (complete genomes) for an increasing number of organisms are becoming available each year for use in biological research. However genome project groups incorporate their own formats (or schemas) for representing the genome data accumulated by the projects. Such heterogeneity of their schemas prevents researchers from exchanging and comparing their data across genomes. In this paper we present a new method for exchanging and querying information on complete genomes. Since genomes and the genetic information encoded on them have a hierarchical structure they can be represented as a kind of structured document. We propose a document language called GXML for representing complete genomes. The document language based on XML can be used to exchange many kinds of genomic data and offers a high degree of extensibility. We also define a query language called GQL to operate on the genome documents. Using this language one can easily associate henes among different genomes and perform other biological analyses. We developed a prototype system based on the language. Using the system we executed several test queries. The results were consistent with those published in biological literature. The processor and memory requirements of the prototype system were accptable.
著者
Md. Mottaleb HOSSAIN Md. Abdullah-AL HUMAYUN Md. Tanvir HASAN Ashraful Ghani BHUIYAN Akihiro HASHIMOTO Akio YAMAMOTO
出版者
一般社団法人 電子情報通信学会
雑誌
IEICE Transactions on Electronics (ISSN:09168524)
巻号頁・発行日
vol.E95.C, no.2, pp.255-261, 2012-02-01 (Released:2012-02-01)
参考文献数
26
被引用文献数
2 9

This paper reports on a theoretical study and modeling of a 1.55µm quantum dot heterostructure laser using InN as a promising candidate for the first time. Details of design and theoretical analysis of probability distribution of the optical transition energy, threshold current density, modal gain, and differential quantum efficiency are presented considering a single layer of quantum dots. Dependence of threshold current density on the RMS value of quantum dot size fluctuations and the cavity length is studied. A low threshold current density of ∼51Acm-2 is achieved at room temperature for a cavity length of 640µm. An external differential efficiency of ∼65% and a modal gain of ∼12.5cm-1 are obtained for the proposed structure. The results indicate that the InN based quantum dot laser is a promising one for the optical communication system.