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121.
122.
Chul Park 《Journal of Quantitative Spectroscopy & Radiative Transfer》1978,20(5):491-498
The sum of the squares of the electronic transition moments, Σ|Re|2, for the E1Σ+ ?X1Σ+ band system of SiO has been determined from absorption measurements conducted in the reflected-shock region of a shock tube. The test gas was produced by shock-heating a mixture of SiCl4, N2O and Ar, and the spectra were recorded photographically in the 150–230 nm wavelength range. The values of the Σ|Re|2 were determined by comparing the measured absorption spectra with those produced by a line-be-line synthetic spectrum calculation. The value of the Σ|Re|2 so deduced at an r-centroid value of 3.0 Bohr was 0.86±0.10 atomic units. 相似文献
123.
K. N. Kocharian V. E. Harutunian R. M. Martirossian A. A. Avakian R. Kh. Kamanchajian Kiejin Lee Jaegab Lee Gwangseo Park 《International Journal of Infrared and Millimeter Waves》1991,12(7):749-755
Transmission spectra of Sr2Ca2Cu4Oy, which is a part of high Tc superconducting system Bi2Sr2Can–1CunOz, and their temperature evolutions were investigated by monochromatic quasioptical submillimeter spectroscopy. Strong increase of high frequency conductivity in the range 80 to 350K was revealed. The obtained results were analyzed on basis of thermally activated carriers model. 相似文献
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125.
O. Yavas P. Leiderer H. K. Park C. P. Grigoropoulos C. C. Poon W. P. Leung N. Do A. C. Tam 《Applied Physics A: Materials Science & Processing》1994,58(4):407-415
The dynamics of liquid-vapor phase-change in the nanosecond time-scale induced by pulsed-laser heating of a liquid on a solid sample is studied by means of optical reflectance and scattering measurements, and the piezoelectric detection technique. The liquids studied include water, ethanol, methanol, IsoproPropyl Alcohol (IPA), and mixtures of water and IPA. The threshold fluence for nucleation is determined with high accuracy using the optical and acoustic signals. Heat diffusion calculations performed for the threshold fluences indicate that the liquids are sufficiently superheated before nucleation sets on. The transient optical reflectance signal is analyzed by an effective-medium theory to provide bubble-growth kinetics, so that the bubble-growth velocity for the test liquids could be estimated. In addition, it is observed that, following the thermally induced nucleation, repetitive acoustic cavitation at the surface of the solid sample occurs, with a time interval related to the speed of sound in the liquid. 相似文献
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129.
Yunjae Jung Haesun Park Ding-Zhu Du Barry L. Drake 《Journal of Global Optimization》2003,25(1):91-111
Clustering has been widely used to partition data into groups so that the degree of association is high among members of the same group and low among members of different groups. Though many effective and efficient clustering algorithms have been developed and deployed, most of them still suffer from the lack of automatic or online decision for optimal number of clusters. In this paper, we define clustering gain as a measure for clustering optimality, which is based on the squared error sum as a clustering algorithm proceeds. When the measure is applied to a hierarchical clustering algorithm, an optimal number of clusters can be found. Our clustering measure shows good performance producing intuitively reasonable clustering configurations in Euclidean space according to the evidence from experimental results. Furthermore, the measure can be utilized to estimate the desired number of clusters for partitional clustering methods as well. Therefore, the clustering gain measure provides a promising technique for achieving a higher level of quality for a wide range of clustering methods. 相似文献
130.
The non-commutative torus C
*(n,) is realized as the C*-algebra of sections of a locally trivial C*-algebra bundle over S with fibres isomorphic to C
*n/S, 1) for a totally skew multiplier 1 on n/S. D. Poguntke [9] proved that A
is stably isomorphic to C(S) C(*( Zn/S, 1) C(S) A Mkl( C) for a simple non-commutative torus A and an integer kl. It is well-known that a stable isomorphism of two separable C*-algebras is equivalent to the existence of equivalence bimodule between them. We construct an A-C(S) A-equivalence bimodule. 相似文献