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991.
A Rusek B Bassalleck A Berdoz T Bürger M Burger RE Chrien GE Diebold H En'yo H Fischer GB Franklin J Franz T Iijima K Imai J Lowe R Magahiz A Masaike CA Meyer R McCrady F Merrill S Mihara JM Nelson K Okada PH Pile B Quinn E R?ssle N Saito R Sawafta H Schmitt RA Schumacher RL Stearns R Stotzer R Sukaton R Sutter F Takeutchi DM Wolfe K Yamamoto S Yamashita S Yokkaichi V Zeps R Zybert 《Canadian Metallurgical Quarterly》1996,54(1):R15-R19
992.
T Minami K Gondo T Yamamoto S Yanai K Tasaki K Ueda 《Canadian Metallurgical Quarterly》1996,39(3):326-334
We report the detailed analysis of the generator and propagation of rolandic discharges in benign childhood epilepsy with centrotemporal spikes by means of 37-channel magnetoencephalography with neuromagnetic three-dimensional dipole localization. Equivalent current dipoles of prominent negative sharp waves of rolandic discharges appeared as tangential dipoles in the rolandic region, positive poles being situated anteriorly. These equivalent current dipoles showed a relatively limited localization and regular directions compared with other components. Equivalent current dipoles of preceding small positive waves, positive waves following negative sharp waves, and negative slow waves appeared in the vicinity of negative sharp waves. Equivalent current dipoles of rolandic discharges were located around the generator of somatosensory evoked magnetic fields stimulated at the lower lip. These findings suggest that rolandic discharges are generated through basically a mechanism similar to that for the middle-latency components of somatosensory evoked responses. 相似文献
993.
994.
M. Yamamoto Y. Nagato S. Higashitani K. Nagai 《Journal of Low Temperature Physics》2005,138(1-2):349-354
No Heading A microscopic theory of transverse acoustic impedance of superfluid 3He at low temperatures is presented. we calculate the stress tensor of superfluid 3He as a response to the oscillating rough wall. For that purpose, we extend a quasi-classical theory based on the random S-matrix model to time dependent problems. We show that by virtue of the pair breaking mechanism the transverse impedance can be finite even at T=0 K. This is in contrast to the theories using the quasi-particle distribution function which predict that the impedance tends to zero like a Yosida function.PACS numbers: 67.57.Np, 67.57.Jj 相似文献
995.
An LSI-based user-network interface circuit, applicable to a network terminal (NT) for the integrated services digital network (ISDN) basic interface is developed. Adaptive timing extraction, with a simplified polyphase phase-locked oscillator, is introduced into the circuit for application to both point-to-point and passive bus configurations. This circuit does not require any manual adjustment. In addition to the primitives defined by CCITT between layers one and two, a new primitive is adopted for controlling the transmission of information. This primitive avoids premature transmission due to processing delays in the exchange terminal (ET). The above functions are fabricated on a CMOS gate-array LSI chip with 4000 gates. The performance of the interface circuit is confirmed with special attention to transmission and electrical characteristics 相似文献
996.
997.
Tomoko Akai Koji Kuraoka Danping Chen Yoshihiro Yamamoto Tatsuya Shirakami Kazuyori Urabe Tetsuo Yazawa 《Journal of the American Ceramic Society》2005,88(10):2962-2965
The leaching behavior of Na from soda–lime–silicate glass was investigated by preparing glass powders with average particle diameters of 53 and 19 μm, and leaching in HNO3 at 90°−140°C. A new theoretical equation for Na leaching from a spherical particle is proposed based on the assumption that a rate-determining process is the three-dimensional self-diffusion of Na in glass. The diffusion constant ( D ) of Na in glass was obtained by fitting the experimental data to a theoretical equation. The values of D and activation energy obtained are comparable to those obtained in other studies on larger particles. 相似文献
998.
Amparo Lpez‐Rubio Pilar Hernndez‐Muoz Enrique Gimenez Tomoyuki Yamamoto Rafael Gavara Jose M. Lagarn 《应用聚合物科学杂志》2005,96(6):2192-2202
Ethylene vinyl alcohol (EVOH)–based packaging structures were analyzed in terms of both barrier properties and morphological alterations after a retorting process and as functions of ethylene content. From the results, it was found that the samples do have a substantial decrease in oxygen barrier properties and that the kinetics of recovery strongly depends on the copolymer ethylene fraction. A morphological deterioration was also observed as a result of retorting, particularly for packaging structures composed of EVOH copolymers of low ethylene contents. However, the polymer morphology and barrier properties were restored after a dry thermal treatment of the retorted samples. Interestingly, preannealing of copolymers of low ethylene content rendered them more resistant to the retorting process by means of promoting both a more robust crystallinity and a lower water sorption capacity. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2192–2202, 2005 相似文献
999.
1000.
Yamamoto H. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1989,35(3):572-578
The coding theorem is proved for the system with two noisy channels, each of which is a broadcast channel. It is assumed that the legitimate channel is less noisy than the wiretapped channel. The admissible region of rates and security levels is obtained completely. The relationship of the present results to previous results is examined 相似文献