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991.
It is well-known that linear correlation information is very useful in establishing the statistical properties of random noise or vibration waves. As the amount of data increases, however, calculating the linear correlation function by the usual multiplicative operations for large amounts of data can be very troublesome, and so some simplified practical methods of detecting the correlation function are desirable. In this paper, a practical method of detection of a linear correlation function latent in random noise or vibration waves is proposed, based on use of the conditional probability distribution. First, a general expression for the bivariate joint probability distribution for discrete level sampling is introduced in the form of a series expansion in orthonormal functions. The expansion coefficients give principally the information on linear and non-linear correlations, so that a general expression for the correlation function can be derived by conditional averaging. A new simplified version of this detection method is then presented, which does not require higher order statistical information. Finally, the effectiveness of the method is confirmed experimentally by applying it to some actual street noise in Hiroshima City. 相似文献
992.
S. Nakashima S. Oima A. Mitsuishi T. Nishimura T. Fukumoto Y. Akasaka 《Solid State Communications》1981,40(7):765-768
Recovery of crystallinity in ion-implanted and c.w.-laser annealed polycrystalline silicon films has been examined by the Raman spectroscopy. The variation of the Raman frequency and width with laser annealing and thermal annealing shows the presence of uniform strain in the laser annealed polysilicon. It is found that the subsequent thermal annealing releases the strain. 相似文献
993.
A. Pyatenko K. Shimokawa M. Yamaguchi O. Nishimura M. Suzuki 《Applied Physics A: Materials Science & Processing》2004,79(4-6):803-806
We have successfully produced silver nanoparticles by irradiating an Ag target with a 532-nm laser beam in pure water. By working with high laser power and small spot sizes, we were able to synthesize very small spherical particles with a typical size of 2–5 nm. The influence of the beam spot size, the laser power, and the ablation time were studied, and the possible mechanisms of particle formation are discussed. PACS 79.20.Ds; 81.07.-b 相似文献
994.
The magnetic hyperfine splitting frequencies of187WFe,182Re(j
π=2+)Ni,183ReNi,186ReNi,186ReFe and203PbFe in a zero external magnetic field have been determined by the NMR-ON method at about 7 mK as 225.56(6), 130.9(1), 98.17(4),
136.6(4), 1007.0(3) and 58.43(3) MHz, respectively. With the knowng-factors ofg(186Re, 1−)=1.739(3) andg(203Pb, 5/2−)=0.27456(20), the following hyperfine fields were deduced:B
HF(186ReNi)=−103.05(35) kG;B
HF(186ReFe)=−759.7(13) kG;B
HF(203PbFe)=+279.18(25) kG. Taking hyperfine anomalies into account, theg-factor of183Re was deduced as |g(183Re, 5/2+)|=1.267(6). With the assumption of Knight shift factorK=0, theg-factors of182Re and187W and the hyperfine field of187WFe were determined as |g(182Re, 2+)|=1.63(5), |g(187W, 3/2−)|=0.414(10) andB
HF(187WFe) =−714(18) kG. The large hyperfine anomaly was deduced to be183W Δ187W =−0.124(22). 相似文献
995.
Akihiko Nishimura Hironori Ohba Koichi Ogura Takemasa Shibata 《Optics Communications》1994,110(5-6):561-564
The absolute values of the oscillator strength ƒ were measured for the six spectral lines of Gd by means of laser absorption spectroscopy with the atomic vapor produced by electron beam heating. The ƒ values obtained for the transition are 0–17381 cm−1, 215–17750 cm−1, 533–17795 cm−1, 999–18070 cm−1, 999–17931 cm−1, 1719–18070 cm−1 were obtained to be 0.0036, 0.012, 0.014, 0.019, 0.0075 and 0.039, respectively. The error of ƒ values was 24% due to uncertainty of metastable states' density. 相似文献
996.
The structure of the “condensed” phase of a finite nucleus is investigated by a HF calculation with a HO-type potential, one-pion-exchange potential and one-rho-meson-exchange potential. The pion field expectation value is also calculated from this nuclear source wave function and compared with the pion field of the normal phase. The time-dependent Schroedinger equation is solved for a certain approximated model of a heavy-ion reaction to see the dynamical growth of the pion field expectation value and its behaviour on such a time scale. The growth of the pion field itself is also investigated to see whether it is a normal growth or that of the condensed phase. 相似文献
997.
998.
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1000.
E. Teramoto F. Yabe K. Fukushima H. Narahara Y. Kiyono S. Togasi M. Kadono N. Nishimura T. Muramatsu 《Journal of Terramechanics》1996,33(2):113-123
A high speed half-tracked truck using a new type of metal-coreless rubber track for traveling and load-carrying both on- and off-road was developed. In this application a conventional embedded-metal rubber track was examined in a first step, and was found to be unsuitable because of its chain-type structure. Then a new type of positive drive metal-coreless rubber track with endless spiral cable reinforcement was developed to meet all of the desired performance, i.e. low driving resistance, low heat build-up due to flexing, low noise, low vibration, light weight, good flexibility, low wear, etc. The development of this track, along with the use of properly matched undercarriage and suspension, has renewed interest in the use of half-tracked trucks. This truck is based on a conventional four-wheel-drive dump truck of two tonnes payload with its rear wheels converted into rubber tracks. Both high mobility off-road and traveling speed faster than 60 km/h on-road are obtained without detracking of the rubber tracks from the undercarriage. Therefore, the truck is capable of transporting its load between on- and off-road without transshipment. An identical driver's license for the same category as the original truck has been granted by the Japanese Ministry of Transportation since 1992. In this paper, the structure of the truck, the metal-coreless rubber track developed especially for high-speed traveling, the test results, and some market applications are reported. 相似文献