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31.
Yukio Iida Masahiro Shibutani Katsuhiko Kobayashi Kazuhiko Ohnuma Yoichi Miyake Toru Noda 《Optical Review》2006,13(2):87-92
The double-pass method is thought to obtain the point spread function (PSF) in human eyes based on two techniques: the symmetric
double-pass method using the same pupil size and the asymmetric double-pass method using a different pupil size. The symmetric
double-pass method provides autocorrelation of the retinal PSF and, thus, the modulation transfer function. The asymmetric
double-pass method provides low-frequency partial-phase information and the partial phase-retrieval algorithm is applied to
obtain the complete-phase information, and to estimate the PSF. The partial phase-retrieval algorithm is based on the iteration
method proposed by Fineup and Kowalczyk and requires a lengthy computation. In this study, we propose a new high-speed phase-retrieval
algorithm based on the property that the real and imaginary parts of optical transfer functions (OTFs) continuously change
in value. 相似文献
32.
Itaru Hibino Minoru Okita Takayuki Inoue Yasuhiro Banno Masahiro Hoso 《Physical Therapy Research》2008,11(1):1-6
Immobilization is often associated with decreased muscle elasticity. This condition is known as muscle contracture; however, the mechanism remains unclear. The purpose of this study was to clarify the mechanism governing muscle contracture in rat soleus muscle by identifying changes in ankle joint mobility, insoluble collagen concentration and type I and type III collagen isoforms following 1- and 3-week immobilizations. Following a 1-week immobilization, range of motion (ROM) of dorsiflexion declined to 90% of the control value; additionally, ROM dropped to 67.5% of the control value after a 3-week immobilization. This finding suggested that ankle joint mobility decreases in conjunction with extended periods of immobilization. Insoluble collagen concentration in soleus muscles, which was unchanged after 1 week of immobilization, increased 3 weeks after immobilization. These results may be indicative of collagen fibers with strong intermolecular cross-links contained in the muscle was made increased relatively by 3 weeks of immobilization. Therefore, the change in intermolecular cross-links may be significant in terms of progress of muscle contracture with longer periods of immobilization. On the other hand, the ratio of type III to type I collagen isoforms in muscular tissue increased following a 1-week immobilization; moreover, this ratio remained constant after 3 weeks of immobilization. These data suggested that muscle immobilization may induce type III collagen isoform expression. The increase in the ratio of type III to type I collagen isoforms do not change in parallel with the increase in the limitation in ROM; however, this phenomenon probably is not closely related to the progress of muscle contracture. The change of collagen isoform in immobilized muscle may be involved in the mechanism governing the progression of muscle fibrosis. 相似文献
33.
The European Physical Journal H - The Japanese theoretical physicist Ryogo Kubo made remarkable contributions to statistical mechanics and condensed matter physics, amongst which his name is most... 相似文献
34.
The pulse lasers, YAG-, CO2-, and N2-lasers, are examined for use in the cleaning of glass. Cleaning is found to be due to the evaporation and sputtering of stains on the glass by the heat energy of the laser light. Only the N2 laser can be used for the cleaning of the exit surface of the glass (the opposite side to the laser). A laser with a high peak power of about 106J/s and short-pulse duration below 100 ns is found to be necessary in practice. 相似文献
35.
We study rule induction from two decision tables as a basis of rough set analysis of more than one decision tables. We regard the rule induction process as enumerating minimal conditions satisfied with positive examples but unsatisfied with negative examples and/or with negative decision rules. From this point of view, we show that seven kinds of rule induction are conceivable for a single decision table. We point out that the set of all decision rules from two decision tables can be split in two levels: a first level decision rule is positively supported by a decision table and does not have any conflict with the other decision table and a second level decision rule is positively supported by both decision tables. To each level, we propose rule induction methods based on decision matrices. Through the discussions, we demonstrate that many kinds of rule induction are conceivable. 相似文献
36.
Roberto M. Serikawa Masahiro Isaka Qinqquan Su Takashi Usui Tatsuya Nishimura Hirokazu Sato 《高压研究》2013,33(1-6):477-489
Abstract Electrochemical evolution of hydrogen gas, oxygen gas and chlorine at the electrodes is the usual reaction in conventional electrolysis of aqueous salt solution. However, here we demonstrate that the electrolysis governing reaction in hydrothermal solutions is different from the electrolysis performed at atmospheric pressure and temperatures up to 100°C. Experimental electrolytic reaction of aqueous salt solution carried out inside a sealed 300-mL batch autoclave showed that; accumulation of hydrogen gas, oxygen gas and chlorine is highly suppressed under hydrothermal (250°C and 7 MPa) conditions. We have also observed that, when organics are present in the aqueous salt solution being hydrothermally electrolyzed, an effective oxidation of organics is accomplished. Furthermore, for hydrothermal electrolytic oxidation (HEO) with oxygen gas added, experimentally observed TOC removal profile demonstrates apparent anodic oxidation electrical current efficiency of almost 200% for highconcentrated acetic acid solutions. 相似文献
37.
In developing a new method to measure the phase distribution of a light wave utilizing the adaptive control of the pupil function with a liquid crystal panel, the optimization procedure for the adaptive control is shown to improve when a local algorithm is adopted. The feasibility of the proposed system is confirmed by computer simulation as well as by some basic experiments. 相似文献
38.
Kenichi Sakamoto Masahiro Yamamoto 《Journal of Mathematical Analysis and Applications》2011,382(1):426-447
We consider initial value/boundary value problems for fractional diffusion-wave equation: , where 0<α?2, where L is a symmetric uniformly elliptic operator with t-independent smooth coefficients. First we establish the unique existence of the weak solution and the asymptotic behavior as the time t goes to ∞ and the proofs are based on the eigenfunction expansions. Second for α∈(0,1), we apply the eigenfunction expansions and prove (i) stability in the backward problem in time, (ii) the uniqueness in determining an initial value and (iii) the uniqueness of solution by the decay rate as t→∞, (iv) stability in an inverse source problem of determining t-dependent factor in the source by observation at one point over (0,T). 相似文献
39.
We consider the approximate controllability by interior control of a partial differential equation with time derivatives of non-integer order. First, we prove the well-posedness of the inhomogeneous problem for the controlled system. Next, we study the dual system and show a weak type of unique continuation property. Finally, we prove the approximate controllability. 相似文献
40.
This paper is concerned with data-based selection of the bandwidth for a data sharpening estimator in nonparametric regression. Two kinds of bandwidths are considered: a bandwidth vector which has a different bandwidth for each covariate, and a scalar bandwidth that is common for all covariates. A plug-in method is developed and its theoretical performance is fully investigated. The proposed plug-in method works efficiently in our simulation study. 相似文献