125 results on '"Akira Konno"'
Search Results
2. Subaru/HSC identifications of protocluster candidates at z ∼ 6–7: Implications for cosmic reionization
- Author
-
Tomotsugu Goto, Masayuki Tanaka, Nobunari Kashikawa, Kei Ito, Seiji Fujimoto, Akira Konno, Eiichi Egami, Yuichi Harikane, Roderik Overzier, Akio K. Inoue, Takatoshi Shibuya, Shogo Ishikawa, Jun Toshikawa, Yutaka Komiyama, Ryo Higuchi, Yi-Kuan Chiang, Masami Ouchi, Yoshiaki Ono, Kenji Hasegawa, and Takashi Kojima
- Subjects
Physics ,COSMIC cancer database ,010308 nuclear & particles physics ,Space and Planetary Science ,0103 physical sciences ,Astronomy ,Astronomy and Astrophysics ,010303 astronomy & astrophysics ,01 natural sciences ,Reionization - Abstract
We report fourteen and twenty-eight protocluster candidates at z = 5.7 and 6.6 over 14 and 19 deg2 areas, respectively, selected from 2,230 Lyα emitters (LAEs) photometrically identified with Subaru/Hyper Suprime-Cam (HSC) deep images. Six out of the 42 protocluster candidates include at least 1 spectroscopically confirmed LAEs at redshifts up to z = 6.574. By the comparisons with the cosmological Lyα radiative transfer (RT) model reproducing LAEs with the reionization effects, we find that more than a half of these protocluster candidates might be progenitors of the present-day clusters with a mass of ≳ 1014M⊙. We also investigate the correlation between LAE overdensity and Lya rest-frame equivalent width (EW), because the cosmological Lyα RT model suggests that a slope of EW-overdensity relation is steepened towards the epoch of cosmic reionization (EoR), due to the existence of the ionized bubbles around galaxy overdensities easing the escape of Lyα emission from the partly neutral intergalactic medium. The available HSC data suggest that the slope of the EW-overdensity correlation does not evolve from the post-reionization epoch z = 5.7 to the EoR z = 6.6 beyond the moderately large statistical errors.
- Published
- 2019
3. SILVERRUSH. VI. A simulation of Lyα emitters in the reionization epoch and a comparison with Subaru Hyper Suprime-Cam survey early data
- Author
-
Akio K. Inoue, Kazuhiro Shimasaku, Ikkoh Shimizu, Masayuki Umemura, Yuichi Harikane, Kenji Hasegawa, Ryo Higuchi, Akira Konno, Takatoshi Shibuya, Chien-Hsiu Lee, Hidenobu Yajima, Masami Ouchi, Yoshiaki Ono, Tomoaki Ishiyama, and Haruka Kusakabe
- Subjects
Physics ,010308 nuclear & particles physics ,Space and Planetary Science ,Epoch (reference date) ,Intergalactic medium ,0103 physical sciences ,Dark Ages ,Astronomy ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,010303 astronomy & astrophysics ,01 natural sciences ,Reionization - Abstract
The survey of Lyman $\alpha$ emitters (LAEs) with Subaru Hyper Suprime-Cam, called SILVERRUSH (Ouchi et al.), is producing massive data of LAEs at $z\gtrsim6$. Here we present LAE simulations to compare the SILVERRUSH data. In 162$^3$ comoving Mpc$^3$ boxes, where numerical radiative transfer calculations of reionization were performed, LAEs have been modeled with physically motivated analytic recipes as a function of halo mass. We have examined $2^3$ models depending on the presence or absence of dispersion of halo Ly$\alpha$ emissivity, dispersion of the halo Ly$\alpha$ optical depth, $\tau_\alpha$, and halo mass dependence of $\tau_\alpha$. The unique free parameter in our model, a pivot value of $\tau_\alpha$, is calibrated so as to reproduce the $z=5.7$ Ly$\alpha$ luminosity function (LF). We compare our model predictions with Ly$\alpha$ LFs at $z=6.6$ and $7.3$, LAE angular auto-correlation functions (ACFs) at $z=5.7$ and $6.6$, and LAE fractions in Lyman break galaxies at $5, Comment: PASJ in press, 30 pages, 20 figures
- Published
- 2018
4. The stellar mass, star formation rate and dark matter halo properties of LAEs at z ∼ 2
- Author
-
Peter Capak, Akira Konno, Yuichi Harikane, John D. Silverman, Haruka Kusakabe, Kimihiko Nakajima, Kazuhiro Shimasaku, Masami Ouchi, Ryosuke Goto, and Takuya Hashimoto
- Subjects
Physics ,Stellar mass ,Stellar population ,010308 nuclear & particles physics ,Star formation ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Mass ratio ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Dark matter halo ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Spectral energy distribution ,Halo ,Large Magellanic Cloud ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present average stellar population properties and dark matter halo masses of $z \sim 2$ \lya emitters (LAEs) from SED fitting and clustering analysis, respectively, using $\simeq$ $1250$ objects ($NB387\le25.5$) in four separate fields of $\simeq 1$ deg$^2$ in total. With an average stellar mass of $10.2\, \pm\, 1.8\times 10^8\ {\mathrm M_\odot}$ and star formation rate of $3.4\, \pm\, 0.4\ {\mathrm M_\odot}\ {\rm yr^{-1}}$, the LAEs lie on an extrapolation of the star-formation main sequence (MS) to low stellar mass. Their effective dark matter halo mass is estimated to be $4.0_{-2.9}^{+5.1} \times 10^{10}\ {\mathrm M_\odot}$ with an effective bias of $1.22^{+0.16}_{-0.18}$ which is lower than that of $z \sim 2$ LAEs ($1.8\, \pm\, 0.3$), obtained by a previous study based on a three times smaller survey area, with a probability of $96\%$. However, the difference in the bias values can be explained if cosmic variance is taken into account. If such a low halo mass implies a low HI gas mass, this result appears to be consistent with the observations of a high \lya escape fraction. With the low halo masses and ongoing star formation, our LAEs have a relatively high stellar-to-halo mass ratio (SHMR) and a high efficiency of converting baryons into stars. The extended Press-Schechter formalism predicts that at $z=0$ our LAEs are typically embedded in halos with masses similar to that of the Large Magellanic Cloud (LMC); they will also have similar SHMRs to the LMC, if their SFRs are largely suppressed after $z \sim 2$ as some previous studies have reported for the LMC itself., 34 pages, 15 figures, 6 tables. Accepted for publication in PASJ
- Published
- 2018
5. Great Optically Luminous Dropout Research Using Subaru HSC (GOLDRUSH). I. UV Luminosity Functions at $z \sim 4-7$ Derived with the Half-Million Dropouts on the 100 deg$^2$ Sky
- Author
-
Masami Ouchi, Masayuki Tanaka, Mohammad Akhlaghi, Yoshiaki Ono, Masayuki Akiyama, Satoshi Miyazaki, Yutaka Komiyama, Marcin Sawicki, Yoshiki Matsuoka, Lihwai Lin, Suraphong Yuma, Michael Rauch, Jun Toshikawa, Kazuhiro Shimasaku, Kimihiko Nakajima, Tohru Nagao, Yoshiaki Taniguchi, Shiang-Yu Wang, Chris J. Willott, Yuichi Harikane, John D. Silverman, Akira Konno, Jean Coupon, Nobunari Kashikawa, Masamune Oguri, Takatoshi Shibuya, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Centre de Recherche Astrophysique de Lyon ( CRAL ), École normale supérieure - Lyon ( ENS Lyon ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), and École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL)
- Subjects
Physics ,010308 nuclear & particles physics ,media_common.quotation_subject ,[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph] ,Dropout (communications) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Luminosity ,galaxies: high-redshift ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,galaxies: formation ,galaxies: evolution ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
We study the UV luminosity functions (LFs) at $z\sim 4$, $5$, $6,$ and $7$ based on the deep large-area optical images taken by the Hyper Suprime-Cam (HSC) Subaru strategic program (SSP). On the 100 deg$^2$ sky of the HSC SSP data available to date, we make enormous samples consisting of a total of 579,565 dropout candidates at $z\sim 4-7$ by the standard color selection technique, 358 out of which are spectroscopically confirmed by our follow-up spectroscopy and other studies. We obtain UV LFs at $z \sim 4-7$ that span a very wide UV luminosity range of $\sim 0.002 - 100 \, L_{\rm UV}^\ast$ ($-26 < M_{\rm UV} < -14$ mag) by combining LFs from our program and the ultra-deep Hubble Space Telescope legacy surveys. We derive three parameters of the best-fit Schechter function, $\phi^\ast$, $M_{\rm UV}^\ast$, and $\alpha$, of the UV LFs in the magnitude range where the AGN contribution is negligible, and find that $\alpha$ and $\phi^\ast$ decrease from $z\sim 4$ to $7$ with no significant evolution of $M_{\rm UV}^\ast$. Because our HSC SSP data bridge the LFs of galaxies and AGNs with great statistical accuracy, we carefully investigate the bright end of the galaxy UV LFs that are estimated by the subtraction of the AGN contribution either aided with spectroscopy or the best-fit AGN UV LFs. We find that the bright end of the galaxy UV LFs cannot be explained by the Schechter function fits at $> 2 \sigma$ significance, and require either double power-law functions or modified Schechter functions that consider a magnification bias due to gravitational lensing., Comment: 30 pages, 13 figures, accepted for publication in PASJ special issue
- Published
- 2018
6. SILVERRUSH. IV. Lyα luminosity functions at z = 5.7 and 6.6 studied with ∼1300 Lyα emitters on the 14–21 deg2 sky
- Author
-
Yoshiaki Taniguchi, Kimihiko Nakajima, Hisanori Furusawa, Akira Konno, Masami Ouchi, Yuichi Harikane, Yoshiaki Ono, Nobunari Kashikawa, Tomotsugu Goto, Masakazu A. R. Kobayashi, Masamune Oguri, Masaru Kajisawa, Takatoshi Shibuya, Haruka Kusakabe, Satoshi Miyazaki, Kazuhiro Shimasaku, Shiang-Yu Wang, Ryo Higuchi, Akio K. Inoue, Yutaka Komiyama, and Tohru Nagao
- Subjects
Physics ,010308 nuclear & particles physics ,media_common.quotation_subject ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Cosmology ,Luminosity ,Space and Planetary Science ,Sky ,0103 physical sciences ,Dark Ages ,010303 astronomy & astrophysics ,Reionization ,media_common ,Luminosity function (astronomy) - Published
- 2017
7. SILVERRUSH. II. First catalogs and properties of ∼2000 Lyα emitters and blobs at z ∼ 6–7 identified over the 14–21 deg2 sky*
- Author
-
Kimihiko Nakajima, Hisanori Furusawa, Yoshiaki Taniguchi, Haruka Kusakabe, Rieko Momose, Masami Ouchi, Ryo Higuchi, Takatoshi Shibuya, Masakazu A. R. Kobayashi, Yoshiaki Ono, Tohru Nagao, Yutaka Komiyama, Yuichi Harikane, Chien-Hsiu Lee, Akira Konno, Masaru Kajisawa, Tomotsugu Goto, Masayuki Tanaka, Nobunari Kashikawa, Shiang-Yu Wang, Suraphong Yuma, and Kazuhiro Shimasaku
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,media_common.quotation_subject ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics ,media_common - Abstract
We present an unprecedentedly large catalog consisting of 2,230 > L* Lya emitters (LAEs) at z=5.7 and 6.6 on the 13.8 and 21.2 deg2 sky, respectively, that are identified by the SILVERRUSH program with the first narrowband imaging data of the Hyper Suprime-Cam (HSC) survey. We confirm that the LAE catalog is reliable on the basis of 96 LAEs whose spectroscopic redshifts are already determined by this program and the previous studies. This catalogue is also available on-line. Based on this catalogue, we derive the rest-frame Lya equivalent-width distributions of LAEs at z~5.7-6.6 that are reasonably explained by the exponential profiles with the scale lengths of ~120-170A, showing no significant evolution from z~5.7 to z~6.6. We find that 275 LAEs with a large equivalent width (LEW) of >240A are candidates of young-metal poor galaxies and AGNs. We also find that the fraction of LEW LAEs to all ones is 4% and 21% at z~5.7 and z~6.6, respectively. Our LAE catalog includes 11 Lya blobs (LABs) that are LAEs with spatially extended Lya emission whose profile is clearly distinguished from those of stellar objects at the >~ 3sigma level. The number density of the LABs at z=6-7 is ~ 10^-7-10^-6 Mpc^-3, being ~ 10-100 times lower than those claimed for LABs at z~ 2-3, suggestive of disappearing LABs at z>~6, albeit with the different selection methods and criteria for the low and high-z LABs., 19 pages, 11 figures. Accepted for publication in PASJ special issue
- Published
- 2017
8. SILVERRUSH. III. Deep optical and near-infrared spectroscopy for Lyα and UV-nebular lines of bright Lyα emitters at z = 6–7†‡
- Author
-
Suraphong Yuma, Hisanori Furusawa, Akira Konno, Haruka Kusakabe, Yuichi Harikane, Rieko Momose, Takatoshi Shibuya, Tomotsugu Goto, Shiang-Yu Wang, Masayuki Tanaka, Yutaka Komiyama, Kimihiko Nakajima, Chien-Hsiu Lee, Ryo Higuchi, Crystal L. Martin, Shiro Mukae, Michael Rauch, Tohru Nagao, Masakazu A. R. Kobayashi, Nobunari Kashikawa, Takashi Kojima, Kazuhiro Shimasaku, Masami Ouchi, Yoshiaki Ono, Yoshiaki Taniguchi, and Masaru Kajisawa
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,formation [galaxies] ,010308 nuclear & particles physics ,Near-infrared spectroscopy ,Spectral properties ,FOS: Physical sciences ,Flux ,Astronomy and Astrophysics ,Astrophysics ,Astronomy & Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,early universe ,Luminosity ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Emission spectrum ,Spectroscopy ,010303 astronomy & astrophysics ,high-redshift [galaxies] ,Astronomical and Space Sciences ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Line (formation) - Abstract
We present Lya and UV-nebular emission line properties of bright Lya emitters (LAEs) at z=6-7 with a luminosity of log L_Lya/[erg s-1] = 43-44 identified in the 21-deg2 area of the SILVERRUSH early sample developed with the Subaru Hyper Suprime-Cam (HSC) survey data. Our optical spectroscopy newly confirm 21 bright LAEs with clear Lya emission, and contribute to make a spectroscopic sample of 96 LAEs at z=6-7 in SILVERRUSH. From the spectroscopic sample, we select 7 remarkable LAEs as bright as Himiko and CR7 objects, and perform deep Keck/MOSFIRE and Subaru/nuMOIRCS near-infrared spectroscopy reaching the 3sigma-flux limit of ~ 2x10^{-18} erg s-1 for the UV-nebular emission lines of He II1640, C IV1548,1550, and O III]1661,1666. Except for one tentative detection of C IV, we find no strong UV-nebular lines down to the flux limit, placing the upper limits of the rest-frame equivalent widths (EW_0) of ~2-4 A for He II, C IV, and O III] lines. Here we also investigate the VLT/X-SHOOTER spectrum of CR7 whose 6 sigma detection of He II is claimed by Sobral et al. Although two individuals and the ESO-archive service carefully re-analyze the X-SHOOTER data that are used in the study of Sobral et al., no He II signal of CR7 is detected, supportive of weak UV-nebular lines of the bright LAEs even for CR7. Spectral properties of these bright LAEs are thus clearly different from those of faint dropouts at z~7 that have strong UV-nebular lines shown in the various studies. Comparing these bright LAEs and the faint dropouts, we find anti-correlations between the UV-nebular line EW_0 and UV-continuum luminosity, which are similar to those found at z~2-3., Comment: 26 pages, 12 figures. Accepted for publication in PASJ special issue
- Published
- 2017
9. Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program Strategy and Clustering Properties of ~2,000 Lya Emitters at z=6-7 over the 0.3-0.5 Gpc$^2$ Survey Area
- Author
-
Kimihiko Nakajima, Akira Konno, Kazuhiro Shimasaku, Masayuki Umemura, Kenji Hasegawa, Yuichi Harikane, Yuichi Matsuda, Masao Mori, Masaru Kajisawa, Masami Ouchi, Yoshiaki Ono, Shiang-Yu Wang, Masakazu A. R. Kobayashi, Yoshiaki Taniguchi, T. Saito, Takatoshi Shibuya, Akio K. Inoue, Yutaka Komiyama, Ryo Higuchi, and Tohru Nagao
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Cosmology ,Identification (information) ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Cluster analysis ,010303 astronomy & astrophysics ,Reionization ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present the SILVERRUSH program strategy and clustering properties investigated with $\sim 2,000$ Ly$\alpha$ emitters at $z=5.7$ and $6.6$ found in the early data of the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey exploiting the carefully designed narrowband filters. We derive angular correlation functions with the unprecedentedly large samples of LAEs at $z=6-7$ over the large total area of $14-21$ deg$^2$ corresponding to $0.3-0.5$ comoving Gpc$^2$. We obtain the average large-scale bias values of $b_{\rm avg}=4.1\pm 0.2$ ($4.5\pm 0.6$) at $z=5.7$ ($z=6.6$) for $\gtrsim L^*$ LAEs, indicating the weak evolution of LAE clustering from $z=5.7$ to $6.6$. We compare the LAE clustering results with two independent theoretical models that suggest an increase of an LAE clustering signal by the patchy ionized bubbles at the epoch of reionization (EoR), and estimate the neutral hydrogen fraction to be $x_{\rm HI}=0.15^{+0.15}_{-0.15}$ at $z=6.6$. Based on the halo occupation distribution models, we find that the $\gtrsim L^*$ LAEs are hosted by the dark-matter halos with the average mass of $\log (\left < M_{\rm h} \right >/M_\odot) =11.1^{+0.2}_{-0.4}$ ($10.8^{+0.3}_{-0.5}$) at $z=5.7$ ($6.6$) with a Ly$\alpha$ duty cycle of 1 % or less, where the results of $z=6.6$ LAEs may be slightly biased, due to the increase of the clustering signal at the EoR. Our clustering analysis reveals the low-mass nature of $\gtrsim L^*$ LAEs at $z=6-7$, and that these LAEs probably evolve into massive super-$L^*$ galaxies in the present-day universe., Comment: 16 pages, 10 figures. Accepted for publication in PASJ special issue
- Published
- 2017
10. GOLDRUSH. II. Clustering of Galaxies at $z\sim 4-6$ Revealed with the Half-Million Dropouts Over the 100 deg$^2$ Area Corresponding to 1 Gpc$^3$
- Author
-
Yen-Ting Lin, John D. Silverman, Takatoshi Shibuya, Yutaka Komiyama, Yuichi Harikane, Sheng Chieh Lin, Akira Konno, Atsushi J. Nishizawa, Jean Coupon, Shun Saito, Jun Toshikawa, Kazuhiro Shimasaku, Surhud More, Peter Behroozi, Masami Ouchi, Yoshiaki Ono, Masayuki Akiyama, and Satoshi Miyazaki
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Cluster analysis ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present clustering properties from 579,492 Lyman break galaxies (LBGs) at z~4-6 over the 100 deg^2 sky (corresponding to a 1.4 Gpc^3 volume) identified in early data of the Hyper Suprime-Cam (HSC) Subaru strategic program survey. We derive angular correlation functions (ACFs) of the HSC LBGs with unprecedentedly high statistical accuracies at z~4-6, and compare them with the halo occupation distribution (HOD) models. We clearly identify significant ACF excesses in 10", Comment: 34 pages, 27 figures, PASJ in press
- Published
- 2017
11. The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
- Author
-
Hiroaki Aihara, Nobuo Arimoto, Robert Armstrong, Stéphane Arnouts, Neta A Bahcall, Steven Bickerton, James Bosch, Kevin Bundy, Peter L Capak, James H H Chan, Masashi Chiba, Jean Coupon, Eiichi Egami, Motohiro Enoki, Francois Finet, Hiroki Fujimori, Seiji Fujimoto, Hisanori Furusawa, Junko Furusawa, Tomotsugu Goto, Andy Goulding, Johnny P Greco, Jenny E Greene, James E Gunn, Takashi Hamana, Yuichi Harikane, Yasuhiro Hashimoto, Takashi Hattori, Masao Hayashi, Yusuke Hayashi, Krzysztof G Hełminiak, Ryo Higuchi, Chiaki Hikage, Paul T P Ho, Bau-Ching Hsieh, Kuiyun Huang, Song Huang, Hiroyuki Ikeda, Masatoshi Imanishi, Akio K Inoue, Kazushi Iwasawa, Ikuru Iwata, Anton T Jaelani, Hung-Yu Jian, Yukiko Kamata, Hiroshi Karoji, Nobunari Kashikawa, Nobuhiko Katayama, Satoshi Kawanomoto, Issha Kayo, Jin Koda, Michitaro Koike, Takashi Kojima, Yutaka Komiyama, Akira Konno, Shintaro Koshida, Yusei Koyama, Haruka Kusakabe, Alexie Leauthaud, Chien-Hsiu Lee, Lihwai Lin, Yen-Ting Lin, Robert H Lupton, Rachel Mandelbaum, Yoshiki Matsuoka, Elinor Medezinski, Sogo Mineo, Shoken Miyama, Hironao Miyatake, Satoshi Miyazaki, Rieko Momose, Anupreeta More, Surhud More, Yuki Moritani, Takashi J Moriya, Tomoki Morokuma, Shiro Mukae, Ryoma Murata, Hitoshi Murayama, Tohru Nagao, Fumiaki Nakata, Mana Niida, Hiroko Niikura, Atsushi J Nishizawa, Yoshiyuki Obuchi, Masamune Oguri, Yukie Oishi, Nobuhiro Okabe, Sakurako Okamoto, Yuki Okura, Yoshiaki Ono, Masato Onodera, Masafusa Onoue, Ken Osato, Masami Ouchi, Paul A Price, Tae-Soo Pyo, Masao Sako, Marcin Sawicki, Takatoshi Shibuya, Kazuhiro Shimasaku, Atsushi Shimono, Masato Shirasaki, John D Silverman, Melanie Simet, Joshua Speagle, David N Spergel, Michael A Strauss, Yuma Sugahara, Naoshi Sugiyama, Yasushi Suto, Sherry H Suyu, Nao Suzuki, Philip J Tait, Masahiro Takada, Tadafumi Takata, Naoyuki Tamura, Manobu M Tanaka, Masaomi Tanaka, Masayuki Tanaka, Yoko Tanaka, Tsuyoshi Terai, Yuichi Terashima, Yoshiki Toba, Nozomu Tominaga, Jun Toshikawa, Edwin L Turner, Tomohisa Uchida, Hisakazu Uchiyama, Keiichi Umetsu, Fumihiro Uraguchi, Yuji Urata, Tomonori Usuda, Yousuke Utsumi, Shiang-Yu Wang, Wei-Hao Wang, Kenneth C Wong, Kiyoto Yabe, Yoshihiko Yamada, Hitomi Yamanoi, Naoki Yasuda, Sherry Yeh, Atsunori Yonehara, Suraphong Yuma, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Universitat de Barcelona, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille ( LAM ), and Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Aix Marseille Université ( AMU ) -Centre National d'Etudes Spatiales ( CNES )
- Subjects
media_common.quotation_subject ,FOS: Physical sciences ,01 natural sciences ,0103 physical sciences ,14. Life underwater ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,[ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,media_common ,Summit ,geography.geographical_feature_category ,Cosmologia ,010308 nuclear & particles physics ,Astronomy ,Astronomy and Astrophysics ,Survey research ,Galaxies ,Galàxies ,Cosmology ,Geography ,Space and Planetary Science ,Sky ,Magnitude (astronomy) ,Subaru Telescope ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2m Subaru telescope on the summit of Maunakea in Hawaii. A team of scientists from Japan, Taiwan and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg$^2$ in five broad bands ($grizy$), with a $5\,\sigma$ point-source depth of $r \approx 26$. The Deep layer covers a total of 26~deg$^2$ in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg$^2$). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey., Comment: 14 pages, 7 figures, 5 tables. Corrected for a typo in the coordinates of HSC-Wide spring equatorial field in Table 5
- Published
- 2017
12. First Data Release of the Hyper Suprime-Cam Subaru Strategic Program
- Author
-
Naoshi Sugiyama, Surhud More, Chiaki Hikage, Nobuo Arimoto, Shiro Mukae, Paul T. P. Ho, Chien-Hsiu Lee, Hiroaki Aihara, Hisanori Furusawa, Tomoki Morokuma, Suraphong Yuma, Masato Onodera, Nobunari Kashikawa, Masao Hayashi, Nobuhiro Okabe, Fumihiro Uraguchi, Masamune Oguri, Song Huang, Tsuyoshi Terai, Yukie Oishi, James Bosch, Yukiko Kamata, Philip J. Tait, Yoshiyuki Obuchi, Yen-Ting Lin, Haruka Kusakabe, Yoshihiko Yamada, Yoko Tanaka, Anton T. Jaelani, Anupreeta More, Masahiro Takada, S. Koshida, Rachel Mandelbaum, Masami Ouchi, Atsushi J. Nishizawa, Nobuhiko Katayama, Tomonori Usuda, Akira Konno, Kazuhiro Shimasaku, Robert Armstrong, Yoshiaki Ono, Hiroyuki Ikeda, Joshua S. Speagle, Tomotsugu Goto, Ryoma Murata, Masayuki Tanaka, Yusuke Hayashi, Yuma Sugahara, J. Furusawa, Hitomi Yamanoi, Yoshiki Matsuoka, Rieko Momose, Kuiyun Huang, Sherry Yeh, Yuji Urata, Robert H. Lupton, Michitaro Koike, Shoken Miyama, Michael A. Strauss, James E. Gunn, Shiang-Yu Wang, Krzysztof G. Hełminiak, Yuki Okura, Hisakazu Uchiyama, Melanie Simet, Yoshiki Toba, Ikuru Iwata, Lihwai Lin, Ryo Higuchi, Jean Coupon, Nao Suzuki, Hung-Yu Jian, Takashi Kojima, Hiroshi Karoji, Paul A. Price, Takatoshi Shibuya, Andy D. Goulding, Tomohisa Uchida, Hiroko Niikura, Steven J. Bickerton, Manobu Tanaka, Mana Niida, Edwin L. Turner, Yasushi Suto, Hironao Miyatake, Sogo Mineo, Yuichi Harikane, Dustin Lang, Bau-Ching Hsieh, Hitoshi Murayama, Tohru Nagao, François Finet, Alexie Leauthaud, Masashi Chiba, Fumiaki Nakata, Yousuke Utsumi, M. Onoue, Satoshi Kawanomoto, Takashi Hattori, Masatoshi Imanishi, Tadafumi Takata, Seiji Fujimoto, Yutaka Komiyama, Keiichi Umetsu, Elinor Medezinski, David N. Spergel, Tae-Soo Pyo, Naoki Yasuda, Hiroki Fujimori, and Satoshi Miyazaki
- Subjects
Image quality ,media_common.quotation_subject ,FOS: Physical sciences ,01 natural sciences ,7. Clean energy ,Field (computer science) ,Computer graphics (images) ,0103 physical sciences ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Solar and Stellar Astrophysics (astro-ph.SR) ,media_common ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,High Energy Astrophysical Phenomena (astro-ph.HE) ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Pipeline (software) ,Astrophysics - Astrophysics of Galaxies ,Object detection ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,13. Climate action ,Space and Planetary Science ,Sky ,Data quality ,Astrophysics of Galaxies (astro-ph.GA) ,Subaru Telescope ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered imaging survey aimed at addressing some of the most outstanding questions in astronomy today, including the nature of dark matter and dark energy. The survey has been awarded 300 nights of observing time at the Subaru Telescope and it started in March 2014. This paper presents the first public data release of HSC-SSP. This release includes data taken in the first 1.7 years of observations (61.5 nights) and each of the Wide, Deep, and UltraDeep layers covers about 108, 26, and 4 square degrees down to depths of i~26.4, ~26.5, and ~27.0 mag, respectively (5sigma for point sources). All the layers are observed in five broad bands (grizy), and the Deep and UltraDeep layers are observed in narrow bands as well. We achieve an impressive image quality of 0.6 arcsec in the i-band in the Wide layer. We show that we achieve 1-2 per cent PSF photometry (rms) both internally and externally (against Pan-STARRS1), and ~10 mas and 40 mas internal and external astrometric accuracy, respectively. Both the calibrated images and catalogs are made available to the community through dedicated user interfaces and database servers. In addition to the pipeline products, we also provide value-added products such as photometric redshifts and a collection of public spectroscopic redshifts. Detailed descriptions of all the data can be found online. The data release website is https://hsc-release.mtk.nao.ac.jp/., 34 pages, 20 figures, 7 tables, moderate revision, accepted for publication in PASJ
- Published
- 2017
13. SILVERRUSH. VII. Subaru/HSC Identifications of Protocluster Candidates at z ∼ 6–7: Implications for Cosmic Reionization
- Author
-
Eiichi Egami, Akio K. Inoue, Roderik Overzier, Nobunari Kashikawa, Yi-Kuan Chiang, Shogo Ishikawa, Tomotsugu Goto, Kenji Hasegawa, Takashi Kojima, Masayuki Tanaka, Ryo Higuchi, Kei Ito, Akira Konno, Takatoshi Shibuya, Jun Toshikawa, Masami Ouchi, Yoshiaki Ono, Seiji Fujimoto, Yutaka Komiyama, and Yuichi Harikane
- Subjects
International research ,Physics ,010504 meteorology & atmospheric sciences ,Space and Planetary Science ,0103 physical sciences ,Library science ,Astronomy and Astrophysics ,Christian ministry ,010303 astronomy & astrophysics ,01 natural sciences ,0105 earth and related environmental sciences - Abstract
FIRST program from the Japanese Cabinet Office; Ministry of Education, Culture, Sports, Science and Technology (MEXT); Japan Society for the Promotion of Science (JSPS); Japan Science and Technology Agency (JST); Toray Science Foundation; NAOJ; Kavli IPMU; KEK; ASIAA; Princeton University; National Aeronautics and Space Administration [NNX08AR22G]; National Science Foundation [AST-1238877]; Ehime University; KAKENHI through the Japan Society for the Promotion of Science [23244025, 15H02064]; World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan; Hayakawa Satio Fund - Astronomical Society of Japan
- Published
- 2019
14. [Untitled]
- Author
-
Tatsuaki FURUMOTO, Takashi UEDA, Akira HOSOKAWA, Masaaki WAGA, Naruyoshi SUGIHARA, and Akira KONNO
- Published
- 2009
15. Multifold curdlan gel formation by dialysis into aqueous solutions of metal salts
- Author
-
Masumi Sato, Takao Yamamoto, Masahiro Nobe, Akira Konno, and Toshiaki Dobashi
- Subjects
chemistry.chemical_classification ,Aqueous solution ,Polymers and Plastics ,Magnesium ,Potassium ,Sodium ,Inorganic chemistry ,chemistry.chemical_element ,Salt (chemistry) ,Curdlan ,Calcium ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,refractive index gradient ,chemistry ,Materials Chemistry ,medicine ,dialysis ,Ferric ,curdlan ,liquid crystalline gel ,Physical and Theoretical Chemistry ,liesegang ring ,medicine.drug - Abstract
We have found that the dialysis of curdlan dissolved in alkaline solution into aqueous solutions of metal salts yielded multifold gel structures. Aqueous sodium chloride and potassium chloride as well as pure water induced isotropic gels. Aqueous calcium salts induced liquid crystalline gel with refractive index gradient/amorphous gel alternative structure. Aqueous salts of trivalent aluminum and ferric cations induced a rigid liquid crystalline gel, which shrank above a threshold concentration of each salt. On the other hand, Liesegang ring-like pattern was observed with aqueous solutions of mixed salts of calcium chloride and magnesium chloride. The patterns have been classified to discuss the mechanism of forming the variety of structures.
- Published
- 2005
16. Numerical Analysis for Propellant Management in Rocket Tanks
- Author
-
Takehiro Himeno, Toshinori Watanabe, and Akira Konno
- Subjects
Propellant ,business.product_category ,Buoyancy ,Level set method ,business.industry ,Mechanical Engineering ,Aerospace Engineering ,Structural engineering ,Mechanics ,engineering.material ,Physics::Fluid Dynamics ,Fuel Technology ,Rocket ,Space and Planetary Science ,Storage tank ,engineering ,Wetting ,Liquid oxygen ,business ,Displacement (fluid) - Abstract
To track the three-dimensional behavior of liquid surfaces in storage tanks on orbit, a numerical scheme based on the level set method was developed. For the verification of the numerical methods, experimental data were acquired through the observation of the unsteady deformations of liquid surfaces in cylindrical containers under low-gravity conditions in a drop tower. Primary emphasis was placed on the dynamic behavior of the liquid surface and the displacement of the contact line on the solid wall. Based on the results, the boundary condition for surface tension was discussed and the model of wetting phenomena was adequately introduced into the computation. Compared with the experimental data, the corresponding numerical results showed good agreement. With the developed code, the flowfields at the draining process in the liquid oxygen (LO X ) tank for the upper-stage propulsion system of an H-IIA launch vehicle under low-gravity conditions were also investigated. It was found that the buoyancy induced by a slight acceleration was efficient to prevent dip growth and that the serviceable propellant in the launch-vehicle tank could thereby be increased in a realistic situation.
- Published
- 2005
17. Improvement of Inlet Flow Characteristics of LE-7A Liquid Hydrogen Pump
- Author
-
Kunio Hirata, Akira Konno, Tomoyuki Hashimoto, Masaharu Uchiumi, Satoshi Kobayasi, and Kenjiro Kamijo
- Subjects
geography ,geography.geographical_feature_category ,Materials science ,Suction ,Mechanical Engineering ,Aerospace Engineering ,Mechanical engineering ,Mechanics ,Inlet ,Fuel Technology ,Critical speed ,Space and Planetary Science ,Cavitation ,Inducer ,Turbopump ,Liquid hydrogen ,Backflow - Abstract
LE-7A engine inducers require high head rise and high suction performance in spite of cavitating conditions because a low-speed, low-pressure pump is not used in front of the main pump in the LE-7A engine. During the development phase, use of the LE-7A fuel turbopump with an original inducer resulted in a noticeable deterioration of suction performance near the required net positive suction head. When the pump inlet pressure was gradually reduced, the inducer caused sudden remarkable head degradation, and the rotor vibration was greatly amplified because the frequency of the vibration almost coincided with that of the second critical speed of the turbopump. This vibration was caused by a rotating-stall-type phenomenon, which is considered to be closely related to backflow cavitation at the inducer inlet. Improvement of the inducer was indispensable for enhancement of the reliability of the hydrogen turbopump. Thus, an inlet flow coefficient larger than that of the original inducer was selected to reduce the inlet backflow. A redesign of the original inducer and test results of the hydrogen turbopump with the newly developed inducer are reported.
- Published
- 2003
18. Fundamental Study of Extendible Nozzle and Dual-Bell Nozzle for Reusable Rocket Engine
- Author
-
Masahiro Atsumi, Akinaga Kumakawa, Eijiro Namura, Akira Konno, Kazuo Kusaka, Hiroshi Aoki, Makoto Tadano, Keiichi Hasegawa, and Masahiro Sato
- Subjects
Physics ,Fundamental study ,business.industry ,Nozzle ,Rocket engine ,Bell nozzle ,Aerospace engineering ,business - Abstract
近い将来の再使用型ロケットエンジンの性能向上の一案として,伸展ノズルやデュアルベルノズルが有望であると考えられている.そこで,これらのノズルの基本特性を把握するために,4種のノズル(標準ノズル,伸展途中の過渡状態を模擬したステップノズル,デュアルベルノズルおよび可動伸展ノズル)を用いて,高空性能燃焼試験を実施した.試験で計測したノズル性能,圧力分布および熱伝達率等のデータをCFD解析結果と比較検討した.その結果,デュアルベルノズルの性能は標準ノズルやステップノズルよりも低く,現状のノズルコンターはさらに改良の余地があることが判明した.また,可動伸展ノズルの伸展時には,固定ノズルと伸展ノズル隙間からの燃焼ガスの逆流は認められず,ノズル壁面の熱伝達率は過渡的に約20%増加することが判明した.これらの現象はCFD解析結果とも一致し,CFD解析によってノズルのステップ流れや逆流が予測できる目処を得た.
- Published
- 2003
19. Cocoa extract protects against early alcohol-induced liver injury in the rat
- Author
-
Takehiko Uesugi, Akira Konno, Ronald G. Thurman, Stephen McKim, Erwin Gäbele, Helmut Sies, Mathias Froh, and Gavin E. Arteel
- Subjects
medicine.medical_specialty ,Necrosis ,Flavonoid ,Biophysics ,Weight Gain ,medicine.disease_cause ,Biochemistry ,Enteral administration ,Catechin ,Lipid peroxidation ,chemistry.chemical_compound ,Enteral Nutrition ,Internal medicine ,medicine ,Animals ,Liver Diseases, Alcoholic ,Molecular Biology ,Inflammation ,Liver injury ,chemistry.chemical_classification ,Aldehydes ,Cacao ,Ethanol ,Plant Extracts ,Chemistry ,Cocoa Extract ,Proteins ,food and beverages ,Alanine Transaminase ,medicine.disease ,Rats ,Celiac Disease ,Disease Models, Animal ,Endocrinology ,medicine.symptom ,Oxidative stress ,Phytotherapy - Abstract
Oxidants have been shown to be involved in alcohol-induced liver injury. This study was designed to determine whether cocoa flavonoid extract, composed mostly of epicatechin and epicatechin oligomers, protects against early alcohol-induced liver injury in rats. Male Wistar rats were fed high-fat liquid diets with or without ethanol (10-14 g/kg per day) and cocoa extract (400 mg/kg per day) continuously for 4 weeks using an enteral feeding protocol. Mean body weight gains ( approximately 4 g/day) were not significantly different between treatment groups. Cocoa extract did not affect average daily urine ethanol concentrations ( approximately 200mg/dL). After 4 weeks, serum alanine amino transferase levels of the ethanol group were increased nearly fourfold (110+/-16 IU/L) compared to control values (35+/-3 IU/L); this effect of ethanol was blocked by cocoa extract (60+/-6 IU/L). Additionally, enteral ethanol caused severe fat accumulation, mild inflammation, and necrosis in the liver; cocoa extract significantly blunted these changes. Increases in liver TNFalpha protein levels caused by ethanol were completely blocked by cocoa extract. Further, ethanol significantly increased the accumulation of protein adducts of 4-hydroxynonenal, a product of lipid peroxidation serving as an index of oxidative stress; again this was counteracted by the addition of cocoa extract. These results indicate that dietary flavanols such as those found in cocoa can prevent early alcohol-induced liver injury.
- Published
- 2002
20. [Untitled]
- Author
-
Takanori Kawaguchi, Akira Konno, Shinya Terashima, Ryoichi Motoki, and Yutaka Hoshino
- Subjects
Cancer Research ,Pathology ,medicine.medical_specialty ,biology ,medicine.drug_class ,Colorectal cancer ,Lectin ,General Medicine ,Monoclonal antibody ,medicine.disease ,Staining ,Oncology ,Antigen ,Cancer cell ,medicine ,Cancer research ,biology.protein ,Immunohistochemistry ,Antibody - Abstract
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer.
- Published
- 2002
21. A New Constraint on Reionization from the Evolution of the LyαLuminosity Function atz∼ 6–7 Probed by a Deep Census ofz= 7.0 LyαEmitter Candidates to 0.3L*
- Author
-
Tomonori Totani, Masafusa Onoue, Akifumi Seko, Masanori Iye, Jun Toshikawa, Kazuaki Ota, Y. Fudamoto, Nobunari Kashikawa, Akira Konno, Takatoshi Shibuya, Akie Ichikawa, Fumiaki Nakata, and Masakazu A. R. Kobayashi
- Subjects
Physics ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,Cosmology ,Luminosity ,Constraint (information theory) ,Space and Planetary Science ,0103 physical sciences ,Dark Ages ,010303 astronomy & astrophysics ,Reionization ,Luminosity function (astronomy) ,Common emitter - Published
- 2017
22. Determination of full material constants of ScAlN thin film from bulk and leaky Lamb waves in MEMS-based samples
- Author
-
Jun-ichi Kushibiki, Yasuo Yamamoto, Michio Kadota, Shuji Tanaka, Yuji Ohashi, Masayoshi Esashi, and Akira Konno
- Subjects
Microelectromechanical systems ,Microscope ,Materials science ,business.industry ,law.invention ,Resonator ,Lamb waves ,Optics ,law ,Material constants ,Ultrasonic sensor ,Thin film ,Phase velocity ,Composite material ,business - Abstract
The full material constants of a 40% Sc-AlN thin film were systematically determined. First, 4 kinds of MEMS resonators and a Lamb wave resonator were used to determine the material constants as much as possible. The other unknown material constants together with the material constants which needed more accurate estimation were determined based on ultrasonic microspectroscopy and parameter fitting. The phase velocity versus frequency (v-f) characteristics of A 0 and S 0 mode leaky Lamb waves in a self-suspended ScAlN film were measured using an ultrasonic microscope, and then theoretical v-f characteristics were fitted to the measured ones by tuning the material constants as parameters.
- Published
- 2014
23. Two-Phase Flow Behavior in a Liquid Propellant Tank
- Author
-
Takehiro Himeno, Toshinori Watanabe, and Akira Konno
- Subjects
Propellant ,Propellant tank ,Materials science ,Level set method ,Suction ,Liquid-propellant rocket ,business.industry ,Mechanical Engineering ,Numerical analysis ,Flow (psychology) ,Structural engineering ,Mechanics ,Condensed Matter Physics ,Two-phase flow ,business - Abstract
To give appropriate assesment of propellant management systems for space application, the behavior of two-phase flows under low gravity conditions was both experimentally and numerically studied. By use of a numerical analysis method with C-CUP(CIP Combined Unified Procedure)scheme coupled with Level Set method and CSF(continuum Surface Force)model, the flow fields in a liquid rocket propellant tank were simulated. Main concern was placed on the generation of a deep dip of the gas phase. The numerical results were compared with corresponding experimental data obtained in a drop tower, and they showed good agreement. The generation of the dip was clearly revealed, and the phenomenon of gas suction was properly reproduced in the simulation. The effect of gravity force on the dip generation was studied, and it was found that the dip generation was alleviated with increase in the gravity force.
- Published
- 2000
24. Performance and Damage Evaluation of a Regeneratively Cooled Thrust Engine Coated with ZrO2/Ni Functionally Graded Materials. Evaluation Test Results of a Chamber Partially Coated with ZrO2/Ni FGM Made by the Electroforming Method
- Author
-
Makoto Tadano, Akira Konno, Yoichiro Miki, Yukio Kuroda, Masayuki Niino, and Masahiro Sato
- Subjects
Fluid Flow and Transfer Processes ,Materials science ,Mechanical Engineering ,Delamination ,chemistry.chemical_element ,engineering.material ,Chamber pressure ,Thermal barrier coating ,Surface coating ,chemistry ,Coating ,Electroforming ,engineering ,Physical and Theoretical Chemistry ,Composite material ,Combustion chamber ,Carbon - Abstract
A combustion chamber partially coated with ZrO 2 /Ni functionally graded materials (FGM) was cyclically tested, using a bipropellant of nitrogen tetroxide (NTO)/ monomethyl hydrazine (MMH) at a chamber pressure (P c ) of 0.9 MPa, to show the effect of such coatings on the life span of the chamber. This thermal barrier coatings were applied using a process that employed the electroforming method. The C * efficiency (ηC * ) for the durability tests of the partially ZrO 2 /Ni FGM-coated chamber was 97% at P c =0.9 MPa and mixture ratio (MR) of NTO/MMH=1.65. At the cylindrical section of the chamber, the thermal barrier coating subsequent to composed of pure ZrO 2 remained partially intact. However, the inner surface coating of the chamber throat section suffered premature delamination. The typical damage mode observed in a carbon fiber-reinforced carbon matrix (C/C) chamber of a bipropellant engine in our previous study was also seen near the injector face. In the cycle durability tests, the damage to the coating was inspected by means of the Replica method. After a total of 260 firing tests, a profile of the coating damage was obtained by means of a computer-aided micro-analyzer (CMA) system.
- Published
- 1999
25. Characterization of curdlan in aqueous sodium hydroxide
- Author
-
Mitsuo Nakata, Tsuyoshi Kawaguchi, Yuzo Kodama, and Akira Konno
- Subjects
Persistence length ,Aqueous solution ,Polymers and Plastics ,Intrinsic viscosity ,Organic Chemistry ,Analytical chemistry ,Curdlan ,Solvent ,Viscosity ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Radius of gyration ,Static light scattering - Abstract
Curdlan ((1 → 3)-β-D-glucan) was found to be fractionated through liquid—liquid phase equilibrium with the mixture dimethyl sulfoxide + lithium chloride as a solvent and acetone as a precipitant. Light scattering and viscosity measurements were made on solutions of fractionated samples in 0.3 M NaOH in the range of the molecular weight Mw, from 5.3 × 104 to 2.0 × 106. The observed intrinsic viscosity [η] was analysed by the Yamakawa—Fujii—Yoshizaki theory of a wormlike chain, and the persistence length, molecular weight per unit contour length and molecular diameter were determined roughly as 6.8 nm, 890 g nm−1 and 1.1 nm, respectively. These molecular parameters represented the molecular weight dependence of [η] and the mean-square radius of gyration 〈s2〉z, reasonably indicating an effect of the excluded volume at large Mw. Detailed behaviour of curdlan in 0.3 M NaOH could not be revealed on account of a large uncertainty caused by microgel aggregates in the light scattering measurements.
- Published
- 1998
26. ScAlN Lamb wave resonator in GHz range released by XeF2 etching
- Author
-
Michio Kadota, Hideki Hirano, Kazuhiko Kano, Masahiro Sumisaka, Shuji Tanaka, Akihiko Teshigahara, Ken-ya Hashimo, Masayoshi Esashi, and Akira Konno
- Subjects
Resonator ,Materials science ,Lamb waves ,business.industry ,Etching (microfabrication) ,Wide-bandgap semiconductor ,Optoelectronics ,Thin film ,Reactive-ion etching ,business ,Piezoelectricity ,Electron-beam lithography - Abstract
Recently, it was reported that the piezoelectric characteristic of AlN was enhanced by doping Sc, and that 40% Sc-doped AlN (Sc0.4Al0.6N) had approximately 5 times higher piezoelectricity than pure AlN. In this study, we designed, fabricated and evaluated Lamb wave resonators using a Sc0.4Al0.6N thin film. First, we examined elastic constants c44E and c44D of Sc0.4Al0.6N using a thickness-shear wave resonator excited by parallel electric field, and then designed Lamb wave resonators using revised material constants. The Lamb wave resonators were fabricated by electron beam lithography, reactive ion etching, XeF2 release etching etc. The maximum and average electromechanical coupling coefficients were 8.3% and 6.8%, respectively, for 2.6 GHz devices working in S0 mode.
- Published
- 2013
27. Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program strategy and clustering properties of ∼2000 Lyα emitters at z = 6-7 over the 0.3-0.5 Gpc2 survey area.
- Author
-
Masami OUCHI, Yuichi HARIKANE, Takatoshi SHIBUYA, Kazuhiro SHIMASAKU, Yoshiaki TANIGUCHI, Akira KONNO, Masakazu KOBAYASHI, Masaru KAJISAWA, Tohru NAGAO, Yoshiaki ONO, INOUE, Akio K., Masayuki UMEMURA, Masao MORI, Kenji HASEGAWA, Ryo HIGUCHI, Yutaka KOMIYAMA, Yuichi MATSUDA, Kimihiko NAKAJIMA, Tomoki SAITO, and Shiang-Yu WANG
- Subjects
ASTRONOMICAL surveys ,ASTRONOMICAL instruments ,IMAGING systems in astronomy ,DARK matter ,GALACTIC halos - Abstract
We present the SILVERRUSH program strategy and clustering properties investigated with ∼2,000 Lyα emitters at z=5.7 and 6.6 found in the early data of the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey exploiting the carefully designed narrowband filters. We derive angular correlation functions with the unprecedentedly large samples of LAEs at z=6−7 over the large total area of 14−21 deg2 corresponding to 0.3−0.5 comoving Gpc2. We obtain the average large-scale bias values of bavg=4.1±0.2 (4.5±0.6) at z=5.7 (z=6.6) for ≳L∗ LAEs, indicating the weak evolution of LAE clustering from z=5.7 to 6.6. We compare the LAE clustering results with two independent theoretical models that suggest an increase of an LAE clustering signal by the patchy ionized bubbles at the epoch of reionization (EoR), and estimate the neutral hydrogen fraction to be xHI=0.15
+0.15 −0.15 at z=6.6. Based on the halo occupation distribution models, we find that the ≳L∗ LAEs are hosted by the dark-matter halos with the average mass of log(⟨Mh⟩/M⊙)=11.1+0.2 −0.4 (10.8+0.3 −0.5 ) at z=5.7 (6.6) with a Lyα duty cycle of 1 % or less, where the results of z=6.6 LAEs may be slightly biased, due to the increase of the clustering signal at the EoR. Our clustering analysis reveals the low-mass nature of ≳L∗ LAEs at z=6−7, and that these LAEs probably evolve into massive super-L∗ galaxies in the present-day universe. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
28. SILVERRUSH. II. First catalogs and properties of ~2000 Lyα emitters and blobs at z ~ 6-7 identified over the 14-21 deg2 sky.
- Author
-
Takatoshi SHIBUYA, Masami OUCHI, Akira KONNO, Ryo HIGUCHI, Yuichi HARIKANE, Yoshiaki ONO, Kazuhiro SHIMASAKU, Yoshiaki TANIGUCHI, KOBAYASHI, Masakazu A. R., Masaru KAJISAWA, Tohru NAGAO, Hisanori FURUSAWA, Tomotsugu GOTO, Nobunari KASHIKAWA, Yutaka KOMIYAMA, Haruka KUSAKABE, Chien-Hsiu LEE, Rieko MOMOSE, Kimihiko NAKAJIMA, and Masayuki TANAKA
- Subjects
ASTRONOMICAL catalogs ,ASTRONOMICAL surveys ,GALACTIC redshift ,GALAXY spectra ,REDSHIFT - Abstract
We present an unprecedentedly large catalog consisting of 2230 ≳ L* Lyα emitters (LAEs) at z = 5.7 and 6.6 on the 13.8 and 21.2deg
2 sky, respectively, that are identified by the SILVERRUSH program with the first narrow-band imaging data of the Hyper Suprime-Cam (HSC) survey. We confirm that the LAE catalog is reliable on the basis of 96 LAEs whose spectroscopic redshifts are already determined by this program and previous studies. This catalogue is also available online. Based on this catalogue, we derive the rest-frame Lyα equivalent-width distributions of LAEs at z ≃ 5.7~6.6 that are reasonably explained by the exponential profiles with scale lengths of ≃ 120~170Å, showing no significant evolution from z ≃ 5.7 to z ≃ 6.6. We find that 275 LAEs with large equivalent widths (LEWs) of >240Å are candidates of young metal poor galaxies and AGNs. We also find that the fraction of LEW LAEs to all LAEs is 4% and 21% at z ≃ 5.7 and z ~ 6.6, respectively. Our LAE catalog includes 11 Lyα blobs (LABs) that are LAEs with spatially extended Lyα emission with a profile that is clearly distinguished from those of stellar objects at the ≳3σ level. The number density of the LABs at z = 6~7 is ~10~7 ~10~6 Mpc~3 , being ~10~100 times lower than those claimed for LABs at z ≃ 2~3, suggestive of disappearing LABs at z ≳ 6, albeit with the different selection methods and criteria for the low and high-z LABs. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
29. SILVERRUSH. III. Deep optical and near-infrared spectroscopy for Lyα and UV-nebular lines of bright Lyα emitters at z = 6-7.
- Author
-
Takatoshi SHIBUYA, Masami OUCHI, Yuichi HARIKANE, Michael RAUCH, Yoshiaki ONO, Shiro MUKAE, Ryo HIGUCHI, Takashi KOJIMA, Suraphong YUMA, Chien-Hsiu LEE, Hisanori FURUSAWA, Akira KONNO, MARTIN, Crystal L., Kazuhiro SHIMASAKU, Yoshiaki TANIGUCHI, KOBAYASHI, Masakazu A. R., Masaru KAJISAWA, Tohru NAGAO, Tomotsugu GOTO, and Nobunari KASHIKAWA
- Subjects
NEBULAE ,STELLAR luminosity function ,LUMINOSITY ,OPTICAL spectroscopy ,NEAR infrared spectroscopy ,NEBULA spectra - Abstract
We present Lyα and UV-nebular emission line properties of bright Lyα emitters (LAEs) at z = 6-7 with a luminosity of log L
Lyα /[erg s-1 ] = 43-44 identified in the 21 deg2 area of the SILVERRUSH early sample developed with the Subaru Hyper Suprime-Cam survey data. Our optical spectroscopy newly confirms 21 bright LAEs with clear Lyα emission, and contributes to making a spectroscopic sample of 96 LAEs at z = 6-7 in SILVERRUSH. From the spectroscopic sample, we select seven remarkable LAEs as bright as Himiko and CR7 objects, and perform deep Keck/MOSFIRE and Subaru/nuMOIRCS near-infrared spectroscopy reaching the 3 σ flux limit of ~2 × 10-18 erg s-1 for the UV-nebular emission lines of He II λ1640, C IV λλ1548,1550, and O III]λλ1661,1666. Except for one tentative detection of C IV, we find no strong UV-nebular lines down to the flux limit, placing the upper limits of the rest-frame equivalent widths (EW0 ) of ~2-4 Å for C IV, He II, and O III] lines. We also investigate the VLT/X-SHOOTER spectrum of CR7 whose 6 σ detection of He II is claimed by Sobral et al. Although two individuals and the ESO archive service carefully reanalyzed the X-SHOOTER data that are used in the study of Sobral et al., no He II signal of CR7 is detected, supportive of weak UV-nebular lines of the bright LAEs even for CR7. The spectral properties of these bright LAEs are thus clearly different from those of faint dropouts at z ~ 7 that have strong UV-nebular lines shown in the various studies. Comparing these bright LAEs and the faint dropouts, we find anti-correlations between the UV-nebular line EW0 and the UV-continuum luminosity, which are similar to those found at z ~ 2-3. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
30. GOLDRUSH. II. Clustering of galaxies at z ~ 4-6 revealed with the half-million dropouts over the 100 deg2 area corresponding to 1 Gpc3.
- Author
-
Yuichi HARIKANE, Masami OUCHI, Yoshiaki ONO, Shun SAITO, Peter BEHROOZI, Surhud MORE, Kazuhiro SHIMASAKU, Jun TOSHIKAWA, Yen-Ting LIN, Masayuki AKIYAMA, Jean COUPON, Yutaka KOMIYAMA, Akira KONNO, Sheng-Chieh LIN, Satoshi MIYAZAKI, NISHIZAWA, Atsushi J., Takatoshi SHIBUYA, and John SILVERMAN
- Subjects
GALAXY clusters ,IMAGING systems in astronomy ,GALACTIC halos ,DARK matter ,STAR formation ,GALACTIC redshift ,GALACTIC evolution ,GALAXY formation - Abstract
We present clustering properties from 579492 Lyman-break galaxies (LBGs) at z ~ 4-6 over the 100 deg
2 sky (corresponding to a 1.4 Gpc3 volume) identified in early data of the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. We derive angular correlation functions (ACFs) for the HSC LBGs with unprecedentedly high statistical accuracies at z ~ 4-6, and compare them with the halo occupation distribution (HOD) models. We clearly identify significant ACF excesses in 10" < θ < 90", the transition scale between one- and two-halo terms, suggestive of the existence of the non-linear halo bias effect. Combining the HOD models and previous clustering measurements of faint LBGs at z ~ 4-7, we investigate the dark matter halo mass (Mh) of the z ~ 4-7 LBGs and its correlation with various physical properties including the star formation rate (SFR), the stellar-to-halo mass ratio (SHMR), and the dark matter accretion rate (M˙h) over a wide mass range of Mh/M⊙ = 4 × 1010-4 × 1012 . We find that the SHMR increases from z ~ 4 to 7 by a factor of ~4 at Mh ≃ 1 × 1011 M⊙ , while the SHMR shows no strong evolution in the similar redshift range at Mh ≃ 1 × 1012 M⊙ . Interestingly, we identify a tight relation of SFR/M˙h-Mh showing no significant evolution beyond 0.15 dex in this wide mass range over z ~ 4-7. This weak evolution suggests that the SFR/M˙h-Mh relation is a fundamental relation in high-redshift galaxy formation whose star formation activities are regulated by the dark matter mass assembly. Assuming this fundamental relation, we calculate the cosmic star formation rate densities (SFRDs) over z = 0-10 (a.k.a. the Madau-Lilly plot). The cosmic SFRD evolution based on the fundamental relation agrees with the one obtained by observations, suggesting that the cosmic SFRD increase from z ~ 10 to 4 - 2 (decrease from z ~ 4-2 to 0) is mainly driven by the increase of the halo abundance (the decrease of the accretion rate). [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
31. The stellar mass, star formation rate and dark matter halo properties of LAEs at z ~ 2.
- Author
-
Haruka KUSAKABE, Kazuhiro SHIMASAKU, Masami OUCHI, Kimihiko NAKAJIMA, Ryosuke GOTO, Takuya HASHIMOTO, Akira KONNO, Yuichi HARIKANE, SILVERMAN, John D., and CAPAK, Peter L.
- Subjects
STELLAR mass ,STAR formation ,DARK matter ,LARGE magellanic cloud ,GALACTIC halos - Abstract
We present average stellar population properties and dark matter halo masses of z ~ 2 Lya emitters (LAEs) from spectral energy distribution fitting and clustering analysis, respectively, using ≃ 1250 objects (NB387=25.5) in four separate fields of ≃ 1 deg2 in total. With an average stellar mass of 10.2 ± 1.8 × 10
8 M⊙ and star formation rate of 3.4 ± 0.4 M⊙ yr-1, the LAEs lie on an extrapolation of the star-formation main sequence (MS) to low stellar mass. Their effective dark matter halo mass is estimated to be 4.0... ×1010 M⊙ with an effective bias of 1.22..., which is lower than that of z ~ 2 LAEs (1.8 ± 0.3) obtained by a previous study based on a three times smaller survey area, with a probability of 96%. However, the difference in the bias values can be explained if cosmic variance is taken into account. If such a low halo mass implies a low H I gas mass, this result appears to be consistent with the observations of a high Lya escape fraction. With the low halo masses and ongoing star formation, our LAEs have a relatively high stellar-to-halo mass ratio (SHMR) and a high efficiency of converting baryons into stars. The extended Press-Schechter formalism predicts that at z = 0 our LAEs are typically embedded in halos with masses similar to that of the Large Magellanic Cloud (LMC); they will also have similar SHMRs to the LMC, if their star formation rates are largely suppressed after z ~ 2 as some previous studies have reported for the LMC itself. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
32. Liquid Crystalline Gel Beads of Curdlan
- Author
-
Takao Yamamoto, Toshiaki Dobashi, Akira Konno, Masahiro Nobe, Michiru Koike, and Hiromi Yoshihara
- Subjects
chemistry.chemical_classification ,Materials science ,Chromatography ,chemistry.chemical_element ,Surfaces and Interfaces ,Curdlan ,Polymer ,Calcium ,Bead ,engineering.material ,Condensed Matter Physics ,Amorphous solid ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,visual_art ,Reagent ,Electrochemistry ,visual_art.visual_art_medium ,engineering ,General Materials Science ,Biopolymer ,Thickening agent ,Spectroscopy - Abstract
Curdlan beads consisting of liquid crystalline gel (LCG) and amorphous gel (AG) in alternating layers in a wide range of diameters were newly prepared by interfacial insolubilization reactions using calcium chloride as the setting reagent. The thickness of the liquid crystalline layer was proportional to the diameter of the gel bead, and the proportional constant agreed with that determined for the cylindrical gel prepared by a dialysis method. The proportional constant initially increased with increasing calcium concentration of the dispersing medium and saturated at a high concentration limit. These results suggest that the mechanisms for forming the alternating LCG/AG structures prepared with different boundary conditions are the same. The LCG/AG structure could be controlled by calcium concentration.
- Published
- 2004
33. BRIGHT AND FAINT ENDS OF LyαLUMINOSITY FUNCTIONS ATz= 2 DETERMINED BY THE SUBARU SURVEY: IMPLICATIONS FOR AGNs, MAGNIFICATION BIAS, AND ISM H I EVOLUTION
- Author
-
Akira Konno, Masami Ouchi, Yoshiaki Ono, Kimihiko Nakajima, Kazuhiro Shimasaku, Haruka Kusakabe, and Florent Duval
- Subjects
Physics ,Luminosity (scattering theory) ,Mathematical model ,010308 nuclear & particles physics ,Scattering ,Magnification ,Astronomy and Astrophysics ,Astrophysics ,Inelastic scattering ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Electromagnetic radiation ,Galaxy ,Space and Planetary Science ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Cosmic dust - Abstract
We present the Lya luminosity functions (LFs) derived by our deep Subaru narrowband survey that identifies a total of 3,137 Lya emitters (LAEs) at $z = 2.2$ in five independent blank fields. The sample of these LAEs is the largest, to date, and covers a very wide Lya luminosity range of $\log L_{Ly\alpha} = 41.7-44.4$ erg s$^{-1}$. We determine the Lya LF at $z = 2.2$ with unprecedented accuracies, and obtain the best-fit Schechter parameters of $L^{*}_{Ly\alpha} = 5.29^{+1.67}_{-1.13} \times 10^{42}$ erg s$^{-1}$, $\phi^{*}_{Ly\alpha} = 6.32^{+3.08}_{-2.31} \times 10^{-4}$ Mpc$^{-3}$, and $\alpha = -1.75^{+0.10}_{-0.09}$ showing a steep faint-end slope. We identify a significant hump at the LF bright end ($\log L_{Ly\alpha} > 43.4$ erg s$^{-1}$). Because all of the LAEs in the bright-end hump have (a) bright counterpart(s) either in the X-ray, UV, or radio data, this bright-end hump is not made by gravitational lensing magnification bias but AGNs. These AGNs allow us to derive the AGN UV LF at $z \sim 2$ down to the faint magnitude limit of $M_{UV} \simeq -22.5$, and to constrain the faint-end slope of AGN UV LF, $\alpha_{AGN}=-1.2 \pm 0.1$, that is flatter than those at $z > 4$. Based on the Lya and UV LFs from our and previous studies, we find the increase of Lya escape fraction $f^{Ly\alpha}_{esc}$ from $z \sim 0$ to $6$ by two orders of magnitude. This large $f^{Ly\alpha}_{esc}$ increase can be explained neither by the evolution of stellar population nor outflow alone, but the evolution of neutral hydrogen HI density in inter-stellar medium that enhances dust attenuation for Lya by resonance scattering. Our uniform expanding shell models suggest that the typical HI column density decreases from $N_{HI} \sim 7 \times 10^{19}$ ($z \sim 0$) to $\sim 1 \times 10^{18}$ cm$^{-2}$ ($z \sim 6$) to explain the large $f^{Ly\alpha}_{esc}$ increase., Comment: 18 pages, 10 figures, 5 tables, Accepted for publication in The Astrophysical Journal
- Published
- 2016
34. Effect of heating on formation of curdlan gels
- Author
-
Akira Konno, Atuo Koreeda, Kenji Okuyama, Tokuya Harada, and Akira Harada
- Subjects
chemistry.chemical_classification ,Polymers and Plastics ,Organic Chemistry ,Analytical chemistry ,Curdlan ,Endothermic process ,law.invention ,Crystallinity ,chemistry.chemical_compound ,Differential scanning calorimetry ,chemistry ,law ,Polymer chemistry ,Materials Chemistry ,medicine ,Swelling ,medicine.symptom ,Electron microscope ,Endotherm ,Glucan - Abstract
The characteristics of curdlan preparations that were dehydrated after heating at various temperatures in water were examined by X-ray diffraction, differential scanning calorimetry and electron microscopy. X-Ray diffraction patterns showed that crystallinity was higher in preparations heated to above 80°C, with heated preparations at 170°C having the highest crystallinity. Differential scanning calorimetry showed that the temperature of the endothermic peak caused by swelling decreased and that the peak area became smaller with increasing heating temperatures. Moreover, preparations of (1 → 3)-β- d -glucans of low molecular mass, DPn 131 and 49, with and without heating at 120°C gave similar X-ray diffraction patterns and differential scanning calorimetry curves to those of the original curdlan. The crystallinity was particularly high without heating in the preparation of DP n 49 though the endotherm associated with the breakage of hydrogen bonds was lower and the enthalpy smaller than found for the original curdlan. Electron microscopic studies showed that longer and wider microfibrils were formed in curdlan gels, while shorter microfibrils or crystals were formed with the lower molecular mass samples of (1 → 3)-β- d -glucan, which are incapable of forming gels.
- Published
- 1994
35. The Reality and Evaluation of Mixed-Racial Living in Housing Estates in Johor Bharu Metropolitan Area, Malaysia
- Author
-
Yushi Utaka, Chin Siong Ho, Juichi Yamazaki, Akira Ohgai, and Akira Konno
- Published
- 1993
36. Integrated land use transportation planning in facilitating and guiding the industrialization process in developing countries: The case of the Johor Bahru metropolitan area
- Author
-
Akira Konno and Ho Chin Siong
- Subjects
Economics and Econometrics ,Transportation planning ,Land use ,Strategy and Management ,Mechanical Engineering ,Metropolitan area ,Civil engineering ,Computer Science Applications ,Deregulation ,Industrialisation ,Urbanization ,Automotive Engineering ,Resource management ,Business ,Environmental planning ,Integrated management - Abstract
The developing countries in their effort in promoting and guiding their industrialization program require effective land use and transportation planning to facilitate the urbanization process and optimize the use of resources. The recent rapid industrialization process in the Johor Bahru metropolitan area due to overspill development from Singapore, the Johor (Malaysia) and Batam Island (Indonesia), the Singapore development triangle proposal and policy deregulation of the Johor State government need reexamination of the existing Structure Plan policy (1984) framework for this region. The authors made observations on the current development and land use and transport policy framework of Johor Bahru-Pasir Gudang Structure Plan (1984), Malaysia with a view towards improving the land use and transportation planning approach.
- Published
- 1993
37. Effects of the Addition of Whey Protein Concentrates on the Water-retention Properties and Texture of Ham
- Author
-
Masashiro Kimura and Akira Konno
- Subjects
chemistry.chemical_classification ,Whey protein ,Differential scanning calorimetry ,Isoelectric point ,Chromatography ,chemistry ,Chemical engineering ,Globular protein ,Hydrogen bond ,Sodium ,chemistry.chemical_element ,Sugar ,Endothermic process - Abstract
By alteration of pH values and addition of salts and sugar during the process of ham preparation, the denaturation temperatures of whey protein concentrates (WPC) and their constituents, α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) were investigated by differential scanning calorimetry (DSC). The denaturation temperatures of WPC, α-La, and β-Lg shifted to the higher temperature by alteration of pH values to an isoelectric value for each protein, and addition of sodium chloride. These results may due to alteration of the balance of forces (such as charge-charge interactions, hydrophobic bonding, and hydrogen bonds etc.) which have been implicated in the stabilization of the secondary-tertiary structure of a globular protein according to the change of pH values or addition of sodium chloride. Secondly, effects of the addition of WPC on model hams preparation were studied. The DSC curves of the model ham paste added WPC showed another endothermic peak besides the endothermic peaks that were found in the model ham paste without WPC. From these results, it became evident that WPC, a-La, and β-Lg denaturated at the heating temperature (ca.75°C) in ham preparation process. The ability of water-retention was improved and some properties, such as strength, cohesiveness, elasticity and chewyness, became higher in the ham added WPC.
- Published
- 1993
38. Study of Primary Multiple Cancers Associated with Gastric Cancers. Special Reference to the Lung Cancer and Esophageal Cancer
- Author
-
Akira Konno, Fujio Itou, Tomohisa Ono, Osamu Konno, Masamitsu Ogata, Michihiko Kogure, Jin Inoue, Tomoyuki Kanno, Yutaka Hoshino, Shinya Terashima, Yasushi Teranishi, Ryouichi Motoki, Satoshi Watanabe, and Shin Koyama
- Subjects
Oncology ,CA15-3 ,medicine.medical_specialty ,business.industry ,Gastroenterology ,Cancer ,Esophageal cancer ,medicine.disease ,Internal medicine ,Epidemiology of cancer ,medicine ,Surgery ,CA19-9 ,business ,Lung cancer - Published
- 1993
39. STUDY ON THE METHOD OF READING LANDSCAPE FROM LITERATURE WORKS : A case of Matsusaka settlement from the novel entitled 'The town where there is a castle'
- Author
-
Tomoko Ikeda and Akira Konno
- Subjects
History ,Reading (process) ,media_common.quotation_subject ,Settlement (litigation) ,Archaeology ,media_common - Published
- 1993
40. Development status of H-II rocket cryogenic propulsion systems
- Author
-
Akira Konno, Yoshio Yamada, Mamoru Endo, and Yukio Koyari
- Subjects
Engineering ,Reliability (semiconductor) ,business.product_category ,Rocket ,Geostationary transfer orbit ,business.industry ,Payload ,Aerospace Engineering ,Launch vehicle ,Stage (hydrology) ,Aerospace engineering ,Propulsion ,business - Abstract
The development of H-II launch vehicle was initiated by the National Space Development Agency of Japan in 1985 and has reached its final stage. Based on experiences of the H-I development, both the 1st and the 2nd stages of H-II rocket have employed advanced cryogenic propulsion systems to inject a 4 ton-class payload into geostationary transfer orbit. The second stage is powered by an upgraded version of the H-I's LE-5 cryogenic engine, LE-5A. The qualification firing tests of LE-5A completed in March, 1991 and the captive firing tests of the second stage system are under way. These test results show that its performance and reliability is satisfactory. The first stage uses a newly developed, high performance LH2/LOX engine, LE-7. In the course of the LE-7 development, some technical difficulties were encountered and lead to the delay of the engine qualification firing test and the 1st stage system firing test. This paper presents the current development status of the cryogenic propulsion systems for H-II launch vehicle, placing an emphasis on the test results.
- Published
- 1992
41. A Study of Shoppers Habit and Interrelated Activities of a Large Shopping Centre in the Downtown of Toyokawa City
- Author
-
Hiroyuki Asada, Kenji Nagai, and Akira Konno
- Published
- 1991
42. Process of City Park Planning and the Method of Land Supply for City Park
- Author
-
Kenji Hamada, Jyuichi Yamazaki, Akira Konno, and Kaisei Tei
- Published
- 1991
43. The Characteristic of Valuation of Field Pictures in Townscape Detail Evaluation
- Author
-
Jun-ichi Aoyama, Katsutoshi Kono, and Akira Konno
- Published
- 1991
44. Curdlan: Properties and Application to Foods
- Author
-
Toshio Tawada, Tetsuya Taguchi, Akira Konno, Hiroshi Kasai, Jun Toda, Mamoru Terasaki, and Yukihiro Nakao
- Subjects
Waxy corn ,Chromatography ,Aqueous solution ,Sucrose ,Syneresis ,biology ,Chemistry ,Starch ,Curdlan ,biology.organism_classification ,chemistry.chemical_compound ,Gel strength ,Congelation ,Food Science - Abstract
Gel formation of curdlan at 100–130°C and behaviors of curdlan gels under frozen state were investigated by measuring gel strength and syneresis. Even when aqueous suspensions of curdlan were heated to 100°C or higher, they formed a gel, and gel strength increased with temperature. Curdlan gel was also stable against freezing and thawing. The syneresis of a 4% curdlan gel after freezing and thawing was reduced from 20.6% to about 2.1% by addition of 5% waxy corn starch and to 8.9% by addition of 20% sucrose. Suggested by these findings, new applications to foods have been developed, especially those subject to retorting and/or freezing.
- Published
- 1991
45. A Study on the Characteristic of Valuation of Townscape by Using Modelscope-System Pictures
- Author
-
Yoshitaka Miyamoto, Jun-ichi Aoyama, and Akira Konno
- Published
- 1990
46. A Study on the Works that Regenerate a Shopping District, Seeing the Correspondence Relations between Storekeepers' Conditions and Their Participative Wills
- Author
-
Kenji Nagai, Akira Konno, and Jyuichi Yamazaki
- Published
- 1990
47. A Study on Regional Characteristic and Inhabitants' Activity Areas in the Mountain Village by a Boundary Area of Prefectures
- Author
-
Hiroshi Nagayanagi, Juichi Yamazaki, and Akira Konno
- Published
- 1990
48. The Study on the Frame of Water Use Planning Related with Land Use
- Author
-
Kouichi Bandou, Juichi Yamazaki, and Akira Konno
- Published
- 1990
49. Nuclear Magnetic Resonance Study of Poly(γ-glutamic acid)—Cu(II) and Mn(II) Complexes
- Author
-
Hiroyuki Tanaka, Kunio Hikichi, and Akira Konno
- Subjects
Aqueous solution ,Polymers and Plastics ,Proton ,Inorganic chemistry ,chemistry.chemical_element ,Glutamic acid ,Ion ,Metal ,chemistry.chemical_compound ,Crystallography ,chemistry ,visual_art ,Amide ,Materials Chemistry ,visual_art.visual_art_medium ,Molecule ,Carbon - Abstract
The interactions of poly(γ-glutamic acid) with Cu(II) and Mn(II) ions in aqueous solution were studied by 1H and 13C nuclear magnetic resonances. The addition of Cu(II) ions to poly(γ-glutamic acid) solution selectively broadens the α-proton signal, the side-chain carboxyl carbon signal, and the α-carbon signal. The addition of Mn(II) selectively broadens the α-proton signal, the side-chain carboxyl carbon signal, and the main chain carbonyl carbon signal. It is concluded that the oxygen atom of the side-chain carboxyl group of poly(γ-glutamic acid) binds to Cu(II) and Mn(II) ions in aqueous solution at neutral pH and at room temperature. It is also probable that the nitrogen atom of the amide group binds to Cu(II) and that the oxygen atom of the carbonyl group binds to Mn(II). These groups bound to Cu(II) and Mn(II) ions undergo rapid exchange between the bound and free states, and the life time of the bound state is short, less than 10−4 s for Mn(II) complex.
- Published
- 1990
50. Molecular weight effect on liquid crystalline gel formation of curdlan
- Author
-
Toshiaki Dobashi, Masahiro Nobe, Mitsuo Nakata, Akira Konno, Naomi Kuroda, and Takao Yamamoto
- Subjects
Anions ,beta-Glucans ,Polymers and Plastics ,Macromolecular Substances ,Protein Conformation ,Chemistry, Pharmaceutical ,Analytical chemistry ,Biophysics ,Molecular Conformation ,chemistry.chemical_element ,Bioengineering ,Biocompatible Materials ,Curdlan ,Calcium ,Biophysical Phenomena ,Biomaterials ,chemistry.chemical_compound ,Calcium Chloride ,Suspensions ,Liquid crystal ,Cations ,Polymer chemistry ,Materials Chemistry ,Hydroxides ,Molecule ,Glucans ,Aqueous solution ,Molecular mass ,Dose-Response Relationship, Drug ,Chemistry ,Polysaccharides, Bacterial ,Water ,Random coil ,Elasticity ,Amorphous solid ,Liquid Crystals ,Molecular Weight ,Solutions ,Delayed-Action Preparations ,Gels - Abstract
Curdlan dissolved in alkaline solution forms a unique gel consisting of liquid crystalline gel (LCG) and amorphous gel (AG) in alternating layers by a dialysis into aqueous calcium chloride. The unique structure has been investigated by measuring the birefringence of the gel Deltan, the ratio q of the thickness of LCG layer delta to the gel radius R, and the calcium content in the gel C(Ca) in a wide range of molecular weights of fractionated Curdlan, as well as unfractionated Curdlan as a control. With increasing molecular weight of Curdlan, Deltan increased and q = delta/R decreased, and both became saturated at high molecular weight. Deltan and q for unfractionated Curdlan were smaller and larger, respectively, than those for fractionated Curdlan. C(Ca) was constant irrespective of molecular weight and its distribution, which means that the abundance of calcium ions per glucose unit in the gel does not depend on the degree of orientation of mesogens. These results suggest that the amorphous phase appears when the size of the Curdlan molecules is larger than the average intermolecular distance, resulting from the random coil to triple helix transformation of Curdlan molecules associated with lowering hydroxide anion concentration in the dialysis process.
- Published
- 2005
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.