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121.
The additivity of flicker responses produced by two different wavelengths λ1 and λ2 was investigated for five adapting levels of 560 nm by the summation-index method. A summation-index value of σ of 0.30 was obtained for all conditions employed, confirming the linear property of the achromatic channel. The additivity of unique chromatic responses, red, yellow, green, and blue, was also investigated with the same method. In this case the wavelengths λ1 and λ2 were chosen in a spectral region to produce one of the four unique colors and the summation index was measured for the color with the cancellation method. A summation index of 0.30 was found for the green and blue sensations and also for the red sensation if both stimuli were from the same spectral region. A slight additivity failure of the enhancement type was found for pairs λ1 and λ2 λ1 was in the short-wavelength region while λ2 was in the long-wavelength region. An additivity failure of the same type was found for the yellow chromatic sensation when λ2 was 607 nm and λ1 was 570, 550, or 533 nm, the last combination giving a summation index of as much as 0.64. The results imply the existence of two different cones whose responses do not add linearly to yield the yellow sensation. 相似文献
122.
Akihiko Ohta Yoshio Maeda Masao Kanao 《International Journal of Pressure Vessels and Piping》1984,15(3):229-240
The mean stress effect on the fatigue properties of two kinds of welded pipes was investigated in cantilever bending. The fatigue strength changed with the mean stress on fillet welded pipes, but did not change on butt welded pipes. The fatigue crack initiated from the toe of weld on the outer surface of fillet welded pipes and from the undercut on the inner surface of butt welded pipes. The measurement of the fatigue crack propagation rate and the residual stress distribution through the thickness of pipe revealed that the difference in the fatigue properties between fillet and butt welded pipes arose from the weld-induced residual stress, tension on the inner surface and compression on the outer surface. It is suggested that the production of compressive residual stress along the inner surface would be an effective means for improving the fatigue strength of butt welded pipes. 相似文献
123.
Masao Iwai Hiroshi Majima Yasuhiro Awakura 《Metallurgical and Materials Transactions B》1982,13(3):311-318
The oxidation of Fe(II) with dissolved molecular oxygen was studied in sulfuric acid solutions containing 0.2 mol · dm−3 FeSO4 at temperatures ranging from 343 to 363 K. In solutions of sulfuric acid above 0.4 mol · dm−3, the oxidation of Fe (II) was found to proceed through two parallel paths. In one path the reaction rate was proportional
to both [Fe−2+]2 andp
o
2 exhibiting an activation energy of 51.6 · kJ mol−1. In another path the reaction rate was proportional to [Fe2+]2, [SO
4
2
−], andp
o
2 with an activation energy of 144.6 kJ · mol−1. A reaction mechanism in which the SO
4
2
− ions play an important role was proposed for the oxidation of Fe(II). In dilute solutions of sulfuric acid below 0.4 mol
· dm−3, the rate of the oxidation reaction was found to be proportional to both [Fe(II)]2 andp
o
2, and was also affected by [H+] and [SO
4
2
−]. The decrease in [H+] resulted in the increase of reaction rate. The discussion was further extended to the effect of Fe (III) on the oxidation
reaction of Fe (II). 相似文献
124.
125.
126.
Masao?ShimizuEmail author Masatoshi?Okutomi 《International Journal of Computer Vision》2005,63(3):207-224
Area-based image matching and sub-pixel displacement estimation using similarity measures are common methods that are used in various fields. Sub-pixel estimation using parabola fitting over three points with their similarity measures is also a common method to increase the matching resolution. However, few investigations or studies have explored the characteristics of this estimation.This study analyzed sub-pixel estimation error using two different types of matching model. Our analysis demonstrates that the estimation contains a systematic error depending on image characteristics, the similarity function, and the fitting function. This error causes some inherently problematic phenomena such as the so-called pixel-locking effect, by which the estimated positions tend to be biased toward integer values. We also show that there are good combinations of the similarity functions and fitting functions.In addition, we propose a new algorithm to greatly reduce sub-pixel estimation error. This method is independent of the similarity measure and the fitting function. Moreover, it is quite simple to implement. The advantage of our novel method is confirmed through experiments using different types of images. 相似文献
127.
Polyethylene and polypropylene films were irradiated by γ-irradiation from a Co60 source in butadiene gas flow and in liquid butaidne. Irradiating in the butadiene gas flow is particularly convenient because the gas state monomer is available directly and little homopolymer is produced. In this case, there is a retardative effect on the grafting near the surface of the film and the grafting rate shows the maximum values at 50–60°C. for high-density PE (PEH) and PP. Irradiating in the liquid butadiene decreases the retardative effect near the surface. The effect of dose rate I on the grafting rate Rp is represented by Rp ∞ I1/4 in this case. The grafting rate is always higher in PEH than in low-density PE (PEL). Results of x-ray diffractometry and electron microscopy indicate that the grafting reaction occurs predominantly near the surface of the crystallite (lamella) of PE and the grafting rate is not affected by the overall crystallinity of the trunk polymer but by the configurational structure, such as the degree of branching or side-chain length. 相似文献
128.
129.
Permeation, diffusion and dissolution of hydrogen isotopes, methane and inert gases through/in a tetrafluoroethylene film 总被引:1,自引:0,他引:1
Masao Matsuyama Hitoshi Miyake Kan Ashida Kuniaki Watanabe 《Journal of Nuclear Materials》1982,110(2-3):296-300
Tetrafluoroethylene (TFE) is widely used for conventional tritium handling systems such as vacuum seals, tubing and so on. We measured the permeation of the three hydrogen isotopes, methane and the inert gases through a TFE film at room temperature by means of the time-lag method in order to establish the physicochemical properties which determine the solubility and diffusivity of those gases. It was found that the diffusion constant of the inert gases changed exponentially with the heat of vaporization and the solubility was an exponential function of the Lennard-Jones force constant of the gases. On the other hand, hydrogen isotopes and methane deviated from these relations. It is concluded that chemical interactions between the solute and the solvent play an important role for the dissolution and the diffusion of these gases in TFE. 相似文献
130.
The interaction of various anions with poly(l-arginine) and its two homologues, poly(l-homoarginine) and poly(l-α-amino-γ-guanidinobutyric acid), has been studied in the neutral pH region. These polypeptides were found to change their conformations from coil to helix due to I?, ClO?4 and SCN?, and among them poly(l-homoarginine) and poly(l-arginine) were found to change conformation at smaller concentrations of the anions than poly(l-lysine). The helix of poly(l-homoarginine) was induced in the lyotropic series of the counteranions. Using the van't Hoff enthalpies for the transition of the polypeptides and the transition enthalpies obtained from calorimetry, the various thermodynamic parameters of the transitions were calculated by use of a theory based on the non-specific and the specific binding interactions of the anions with the charged sites on the polypeptides. The binding constants of ClO?4 and SCN? with poly(l-homoarginine) and poly(l-arginine) were found to be four times as large as those with poly(l-lysine). The free energy changes of the transitions from coil to helix of poly(l-homoarginine) and poly(l-arginine) were found to be more negative than that of poly(l-lysine). From these results, the guanidinium ion can be concluded to form easily the ion pair with the anions on the polymer surface, thus allowing poly(l-homoarginine) and poly(l-arginine) to change their conformations at smaller concentrations of the anions than poly(l-lysine). 相似文献