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51.
52.
Kojima Hiroomi Kinoshita Yasuaki Hikita Mitsuaki Tabuchi Toyoji 《Electronics letters》1980,16(12):445-446
Velocity and propagation loss of surface shear waves are measured on free-space and metallised surfaces of LiNbO3 crystals along the x-axis of rotated Y-cut plates as a function of rotation about the x-axis between 35° and 70°. The coupling factor obtained from the velocities is 0.20 for a 35° rotated Y-cut plate and 0.09 for a 70° plate. The coupling factor changes linearly with the rotation angle. The propagation losses over the whole range measured here are less than 5 dB/cm on both free-space and on metallised surfaces. These losses are fairly low and very favourable for fabricating s.a.w. filters. 相似文献
53.
54.
The electrochemical oxidation of a high surface area carbon black (1000 m2/g) was investigated in 96% H3PO4 at 135°C. The total anodic current, the amount of CO2 evolved and the oxygen content of the carbon were all measured as a function of time and potential. Two anodic processes occurred: the formation of a surface oxide and the evolution of CO2. Both decreased with time but at different rates so that CO2 evolution eventually became the major reaction. Various mechanisms to define the corrosion processes are discussed. 相似文献
55.
A comprehensive econometric model was developed to evaluate potential impacts of recombinant bovine somatotropin (rbST) approval in Japan. Three novel features of the analyses include 1) investigation of impact of rbST on herd-size structure, 2) determination of economic feasibilities of rbST adoption by herd size, and 3) evaluation of policies to mitigate negative effects of rbST approval. Simulation analysis was conducted over a 10-yr projected period assuming rbST was approved in Japan in 2001. Nine hypothetical scenarios were simulated to examine sensitivity of simulation results. Simulation results indicate that rbST approval would accelerate structural change in Japan's dairy industry toward fewer, larger farms. Negative effects of rbST on farm income are projected to be more severe for smaller farms, because of higher costs, lower profit-earning ability, lower milk yields, and lower adoption rates of rbST. Larger farms benefit from rbST adoption if milk demand is maintained. However, if concerns about rbST induce significant milk demand decreases, even the largest farms' income and cow numbers will decrease. Thus, Japan's dairy industry could be caught in a double downward spiral of declining milk prices and production. Assuming rbST is approved, small farms would benefit by using the technology, but they fare best if rbST is not approved. Two policies could be effective in mitigating possible farm income losses. First, lost farm income can be offset if dairy cooperatives can exercise greater market power to control fluid milk marketings. Second, because generic milk advertising has positive effects on both milk demand and farm income, increasing check-off rates to fund more advertising could ease farm income losses. 相似文献
56.
In this study, the spatial local optimization method was improved to obtain high precision of optical flow for cases in which
the object movement changes substantially and a method to trace the loci of moving objects was considered. In the spatial
local optimization method, the precision of the optical flow when the object movement changes substantially becomes a problem.
Therefore, to make the object movement relatively small, we obtained flow vectors from the image sequence to drop the resolution
of the original input image sequence to half the initial resolution. flow vectors were then obtained from the original input
image sequence that were smaller than the threshold value. We show that the precision of the optical flow when the object
movement changes substantially is improved by this method. Method used to trace the loci of moving objects was demonstrated.
We obtained clusters from histograms of flow vectors and pursued each cluster. We show that it is possible to trace moving
objects by this method.
This work was presented, in part, at the 7th International Symposium on Artificial Life and Robotics, Oita, Japan, January
16–18, 2002 相似文献
57.
58.
A. Maeda K. Kinoshita Y. Inoue H. Kitano T. Nishizaki T. Sato K. Shibata N. Kobayashi 《Journal of Low Temperature Physics》2003,131(5-6):969-973
We investigated the microwave surface impedance in Zn doped YBa2Cu3O
y
. For low Zn concentrations, crossover frequency
p
and viscosity of vortex do not change significantly (at maximum, factor of 2). This is in sharp contrast to the dramatic change in the zero-field quasiparticle scattering time. The robust nature of viscosity on the impurity doping suggests that the quasiparticle scattering time in the vortex core is determined by a different mechanism from that outside the core. 相似文献
59.
Capacitance-voltage (C-V) characteristics of double-gate ultrathin silicon-on-insulator (SOI) MOSFETs are numerically investigated in detail. The measured back-gate bias dependence is reproduced by the Poisson-Schrodinger solver including the highly precise physical models for many-body interactions of carrier-carrier and carrier-ion, and for incomplete ionization of doping impurities in whole semiconductor regions of n+poly-Si/oxide/SOI/oxide/p-Si capacitor including the volume inversion. In addition, we study the higher subband effect at higher temperature in detail, in order to deduce the impacts of self-heating and nonstatic transport 相似文献
60.
Kojima H. Kinoshita O. Hayakawa N. Endo F. Okubo H. Yoshida M. Ogawa T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(6):1492-1497
From the viewpoint of mitigating global warming by SF6 gas, this paper discusses breakdown (BD) characteristics of different electronegative gas mixtures with N2O gas as SF6 gas substitutes for quasi-uniform electric field under lightning impulse voltage applications. Experimental results revealed the positive synergism in breakdown strength of binary N2O / CO2 and ternary N2O / CO2 / O2 gas mixtures, respectively. Furthermore, N2 gas as a retardant gas was also mixed with the electronegative gas mixtures in order to reduce the electron energy into the effective levels of electron attachment ability by the electronegative gas mixtures. As the result, ternary N2O / CO2 / N2 and quaternary N2O / CO2 / O2 / N2 gas mixtures could exhibit the significant synergistic effect in breakdown strength. The optimum mixture rate of quaternary N2O / CO2 / O2 / N2 gas mixtures was consistent with that estimated by assuming the independent contribution of component gases to the improvement of impulse BD characteristics. 相似文献