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11.
Byelikov A Adachi T Fujita H Fujita K Fujita Y Hatanaka K Heger A Kalmykov Y Kawase K Langanke K Martínez-Pinedo G Nakanishi K von Neumann-Cosel P Neveling R Richter A Sakamoto N Sakemi Y Shevchenko A Shimbara Y Shimizu Y Smit FD Tameshige Y Tamii A Woosley SE Yosoi M 《Physical review letters》2007,98(8):082501
The Gamow-Teller strength distributions below the particle threshold in 138La and 180Ta, deduced from high-resolution measurements of the (3He,t) reaction at 0 degrees, allow us to evaluate the role of charged-current reactions for the production of these extremely rare nuclides in neutrino-nucleosynthesis models. The analysis suggests that essentially all 138La in the Universe can be made that way. Neutrino nucleosynthesis also contributes significantly to the abundance of 180Ta but the magnitude depends on the unknown branching ratio for population of the long-lived isomer. 相似文献
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Kenji Sakamoto Kiyoaki Usami Kazushi Miki 《Molecular Crystals and Liquid Crystals》2015,611(1):153-159
Photo-alignment efficiency of polyimide containing azobenzene in the backbone structure (Azo-PI) is significantly enhanced by exposing the precursor (polyamic acid: Azo-PAA) film to alkyl-amine vapor prior to photo-alignment. In this study, we have investigated the relationships between the alkyl-amine vapor treatment time, the swelling ratio of Azo-PAA films, and the photo-induced in-plane anisotropy. We found that: the Azo-PAA film swells on exposure to alkyl-amine vapor, and the swelling finally saturates; and the photo-induced in-plane anisotropy is correlated very closely with the swelling ratio. In addition, we pointed out the importance of the process order of alkyl-amine vapor treatment and photo-alignment. 相似文献
14.
R. Minami A. Kasugai K. Takahashi N. Kobayashi Y. Mitsunaka K. Sakamoto 《International Journal of Infrared and Millimeter Waves》2006,27(1):13-24
A high efficiency launcher of quasi-optical (QO) mode converters for high power gyrotrons have been designed and tested. A
helical cut launcher radiates the RF power via its straight cut onto the first phase correcting mirror. The launchers have
been optimized for the TE31.8 mode at 170 GHz and TE22.6 mode at 110 GHz by numerically optimizing a launcher surface. The helical cut of the launcher has been optimized by taking
the taper angle into account. Further more, the amplitude of the surface perturbation have been optimized for improved focusing
in order to reduce the diffraction losses at the helical cut. Low power measurement shows a good agreement with the design.
High efficiency characteristics of the design have also been calculated on the assumption of frequency downshift due to the
thermal expansion of the cavity and stepwise frequency tuning by changing the operating mode. Besides, the possibility of
high efficiency launcher for higher mode is discussed, and these results give the prospect to high efficiency long pulse gyrotrons. 相似文献
15.
Susumu Kuwamura Yuuki Yoshinoya Noriaki Miura Fumiaki Tsumuraya Makoto Sakamoto Naoshi Baba 《Optical Review》2011,18(1):19-26
A bispectral method for astronomical speckle imaging utilizes an average speckle bispectrum of an object to derive its Fourier
phase. There has been, however, a problem in conventional bispectral algorithm owing to difficulty in processing bispectral
data in a four-dimensional (4D) space. In this paper, we propose an implementation to overcome this problem, where a one-dimensional
(1D) object projection is reconstructed from a two-dimensional (2D) average bispectrum of speckle projections, and object
projections so obtained at various angles are then tomographically combined into a 2D object image. In this tomographic approach,
processes are separable into those for individual projection angles, implying that bispectral data required to be stored at
a time are from 4D to 2D and computation time can be substantially reduced by parallelizing angle-by-angle processes. We have
performed experiments using simulated and observed data, and have demonstrated the feasibility of the present approach with
an achievable accuracy comparable to that of a conventional approach. 相似文献
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The following first order nonlinear differential equation with a deviating argument $ x'(t) + p(t)[x(\tau (t))]^\alpha = 0 $ is considered, where α > 0, α ≠ 1, p ∈ C[t 0; ∞), p(t) > 0 for t ≧ t 0, τ ∈ C[t 0; ∞), lim t→∞ τ(t) = ∞, τ(t) < t for t ≧ t 0. Every eventually positive solution x(t) satisfying lim t→∞ x(t) ≧ 0. The structure of solutions x(t) satisfying lim t→∞ x(t) > 0 is well known. In this paper we study the existence, nonexistence and asymptotic behavior of eventually positive solutions x(t) satisfying lim t→∞ x(t) = 0. 相似文献
19.
A bayesian approach to binary response curve estimation 总被引:1,自引:0,他引:1
Makio Ishiguro Yosiyuki Sakamoto 《Annals of the Institute of Statistical Mathematics》1983,35(1):115-137
Summary The purpose of the present paper is to propose a practical procedure for the estimation of the binary response curve. The
procedure is based on a model which approximates the response curve by a finely segmented piecewise constant function. To
obtain a stable estimate we assume a prior distribution of the parameters of the model. The prior distribution has several
parameters (hyper-parameters) which are chosen to minimize an information criterion ABIC. The procedure is applicable to data
consisting of observations of a binary response variable and a single explanatory variable. The practical utility of the procedure
is demonstrated by examples of applications to the dose response curve estimation, to the intensity function estimation of
a point process and to the analysis of social survey data. The application of the procedure to the discriminant analysis is
also briefly discussed.
The Institute of statistical mathematics 相似文献
20.
Hiroshi Maejima Yuji Kanetada Hitoshi Sunahori Azusa Murase Takuya Otani Nozomi Sakamoto Osamu Yoshimura Yoshiko Tobimatsu 《Physical Therapy Research》2008,11(1):7-13
The objective of this study was to assess the effect of comprehensive exercise program widely accepted as a community-based physical intervention for the prevention of falling in the elderly persons on their controlling standing balance. Twenty-six community-dwelling elderly persons (13 males and females; 69.8 ± 2.8 years old) participated in this study. Daily exercise was comprised of walking for more than 30 min, stretching, muscle strengthening and balance exercise without exercise equipments. The intervention was continued for three months. Indicators of standing balance related to static balance, dynamic balance and postural response were measured before and after the intervention. As an effect of the intervention on static balance, the sway of center of pressure (COP) in the static stance significantly increased. In the dynamic balance, significant improvements were observed in one leg standing time, the 10-m gait time, functional reach. Additionally, the maximal movable length of COP which subjects can move voluntarily to right and left significantly increased. In the postural response, the integrated electromyography (IEMG) induced by postural response for sudden postural perturbation significantly decreased in the lower leg muscles. Since less muscular activities were sufficient to maintain posture, it was suggested that postural response was elicited more efficiently following the intervention. This study suggested that the comprehensive exercise program, which has been widely introduced as community-based interventions for the prevention of falling, have extensive effects on the control of standing balance covering static balance, dynamic balance and postural response in the elderly persons. 相似文献