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71.
72.
Kitamura Y Shogenji R Yamada K Miyatake S Miyamoto M Morimoto T Masaki Y Kondou N Miyazaki D Tanida J Ichioka Y 《Applied optics》2004,43(8):1719-1727
The authors have proposed an architecture for a compact image-capturing system called TOMBO (thin observation module by bound optics), which uses compound-eye imaging for a compact hardware configuration [Appl. Opt. 40, 1806 (2001)]. The captured compound image is decomposed into a set of unit images, then the pixels in the unit images are processed with digital processing to retrieve the target image. A new method for high-resolution image reconstruction, called a pixel rearrange method, is proposed. The relation between the target object and the captured signals is estimated and utilized to rearrange the original pixel information. Experimental results show the effectiveness of the proposed method. In the experimental TOMBO system, the resolution obtained is four times higher than that of the unit image that did not undergo reconstruction processing. 相似文献
73.
High-power aging tests on 1.3 ?m double-channel planar buried-heterostructure (DC-PBH) lasers with a reflective coated mirror have been performed. Stable operation for over 6000 h has been demonstrated under constant power conditions of 20 and 30 mW from the front facet at 50°C. 相似文献
74.
Recent experimental evidence on spike-timing-dependent plasticity and on phase precession (i.e., the theta rhythm dependent firing of rat hippocampal cells) associates the contribution of phase precession to episodic memory. This article aims at clarifying the role of phase precession in memory storage. Computer simulations show that the memory storage in the behavioral timescale varies in timescale of the temporal sequence from half a second to several seconds. In contrast, the memory storage caused by traditional rate coding is restricted to the temporal sequence within 40 ms. During phase precession, memory storage of a single trial experience is possible, even in the presence of noise. It is therefore concluded that encoding by phase precession is appropriate for memory storage of the temporal sequence in the behavioral timescale. 相似文献
75.
Summary
Poly(N-hydroxyethyl-L-glutamine) (PHEG) hydrogels were prepared by aminolysis of
poly( -benzyl L-glutamate) with 2-aminoethanol and hydrophobic or hydrophilic
crosslinkers, and the effect of the hydrophobicity of the crosslinkers was evaluated.
The swelling properties, tensile properties and enzymatic degradation behavior were
studied in phosphate buffered saline (PBS). The swelling ratio and degradation rate of
these hydrogels were highly dependent on the hydrophobicity of the crosslinkers,
while tensile properties were dependent on the swelling ratio, but not on the
hydrophobicity of the crosskinkers. 相似文献
76.
The structures of water, partitioned in cation-exchange resin particles, were studied on the basis of fluorescence dynamics of Nile Blue A (NB). The fluorescence lifetime of NB in the resin was longer than that in water and increased with increasing cross-linking density of the resin (rho). The results demonstrated that the water structures in the resin were significantly different from those in water and dependent on rho. A study on solvation dynamics of NB in the resin, reflecting structured water around the ion-exchange group, revealed the roles of "bound water" molecules in the water structures, since the solvent relaxation time (tauS) in the resin was much longer than that in water and depended on p; tauS increased from 34 to 55 ps with increasing rho from 2 to 8%. The origin of the rho dependence of tauS was discussed in terms of the separation distance between the ion-exchange groups, and the effects of the counterion of the ion-exchange group on the solvation processes were also discussed. 相似文献
77.
Hiroyuki Hirakata Yoshimasa Takahashi Do Van Truong Takayuki Kitamura 《International Journal of Fracture》2007,145(4):261-271
In order to elucidate the role of plasticity on interface crack initiation from a free edge and crack propagation in a nano-component,
delamination experiments were conducted by a proposed nano-cantilever bend method using a specimen consisting of ductile Cu
and brittle Si and by a modified four-point bend method. The stress fields along the Cu/Si interface at the critical loads
of crack initiation and crack propagation were analyzed by the finite element method. The results reveal that intensified
elastic stresses in the vicinity of the interface edge and the crack tip are very different, although the Cu/Si interface
is identical in both experiments. The plasticity of Cu was then estimated on the basis of the nano-cantilever deflection measured
by in situ transmission electron microscopy. The plasticity affects the stress fields; the normal stress near the interface
edge is intensified while that near the crack tip is much reduced. Both the elasto-plastic stresses are close to each other
in the region of about 10 nm. This suggests that the local interface fracture, namely, the crack initiation at the interface
edge and the crack propagation along the interface, is governed by elasto-plastic normal stress on the order of 10 nm. 相似文献
78.
T. Kitamura 《Chemical Engineering Communications》2013,200(6):795-804
In order to increase the photocatalytic activity on TiO2 thin film per its external surface area, the structure of flat thin film was modified by adding a small amount of polyethylene glycol (PEG) to TiO2 sol solution. By firing PEG contained in a TiO2 gel film, a porous structure was developed. The photocatalytic activities of the thin films prepared thus were evaluated by the degradation of 2-propanol in the aqueous solutions under black light illumination. The photocatalytic activity of TiO2 thin film prepared with added PEG 400 by 2.6 wt% or PEG 2000 by 9.5 wt% was increased by about 30% as compared to that prepared without added PEG. 相似文献
79.
Naoyuki Takaki 《Progress in Nuclear Energy》2000,37(1-4):223-228
Neutronic potential of water-cooled reactor on the efficient use of Uranium by multiple recycling of all actinides have been examined after a brief-review of alternative coolants to sodium which are applicable for fast neutron reactors. The water-cooled reactor which was designed to have tight lattice and lower Hydrogen/Heavy-Metal number density ratio (H/HM<0.5) showed enough neutronic potential to make the fuel cycle closed for actinides and could be feasible to be operated not as a breeder but as a self-fuel sustainer. The recycle system requires no external fissile supply and generates no actinide as waste except for the inevitable recovery loss, therefore the Uranium resource could be efficiently used and sustained for a long period similar to the case of sodium cooled system. 相似文献
80.
Mitsutoshi Okada Tohru Hisamatsu Takayuki Kitamura 《Journal of Thermal Spray Technology》2009,18(1):90-95
A superalloy with a thermal barrier coating (TBC) simulating a gas turbine blade is exposed to a high-temperature environment
to develop a method for predicting the local temperature and Al content in a bond coat (BC). The Al content decreases with
an increase in the test time due to the Al transport induced by the oxidation of the BC and the interdiffusion between the
BC and the substrate. This brings about Al-decreased layer (ADL) at the boundary between the BC and the top coat. The thickness
of the ADL increases in proportion to the square root of the test time, and the temperature dependence of the growth rate
shows an Arrhenius-type behavior. Based on this relation, the local temperature of an in-service blade can be estimated by
measuring the ADL thickness when the operation time is known. The Al content decreases in proportion to the ADL thickness.
The prediction method of the Al content based on the relation is also presented. 相似文献