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111.
112.
Hiroyuki Kamano 《中国物理 C》2009,33(12):1077-1084
We present an overview of a research program for the excited nucleon states in Excited Baryon Analysis Center (EBAC) at Jefferson Lab. Current status of our analysis of the meson production reactions based on the unitary dynamical coupled-channels model is summarized, and the N* pole positions extracted from the constructed scattering amplitudes are presented. Our plans for future developments are also discussed. 相似文献
113.
The positive extended KdV equation with self-consistent sources (eKdV+ ESCSs) is firstly presented and its related linear auxiliary equation is derived. The generalized binary Darboux transformation (DT) is applied to construct some new solutions of the eKdV+ ESCSs such as N-soliton solution, N-double pole solution and nonsingular N-positon solution. The properties of these solutions are analyzed. Moreover, the interaction of two solitons is discussed in detail. 相似文献
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Narrow-track perpendicular write heads are reviewed. Because of the strong magnetic interaction between the write head and double-layered medium in perpendicular recording, various types of media are also considered. Current technology is discussed to illustrate design issues; then, for areal densities beyond 1 Tb/in2, future technological requirements, including single-pole-type (SPT) heads for discrete track and bit-patterned media, are examined based on numerical simulations. 相似文献
117.
We study the characteristics of microstrip ring exhibiting photonic band gap properties. Since the stop band is caused by the reflection of electromagnetic waves at the narrow gap introduced in the ring, the geometry of the ring can influence on the characteristics of stop band. The center frequency of the stop band is determined mainly by the outer ring radius when the line width of the circular ring is rather narrow. But it is determined mainly by the mean ring radius when the ring is not a circular form or the line width of circular ring is wide. The frequency range of the stop band can be varied by a reactive component mounted on the gap. The presence of capacitor (inductor) on the gap decreases (increases) the center frequency and the frequency range of the stop band. Moreover, the stop band can be widened by modifying the geometry of ring. These properties can be useful in the applications to the compact microwave circuits, tunable filters and microwave switches. 相似文献
118.
图腾柱PFC变换器具有效率高,损耗低等优点,本文介绍了其工作原理及电流校正控制方式,提出了一种基于平均电流的电压前馈控制策略,并进行了主电路的参数计算.利用本文所提出的控制策略,可以使数字控制系统在极短的时间内对外界电压突变做出反映,提高系统响应时间和稳定性.并通过Simulink搭建了系统仿真模型,仿真表明该控制方法... 相似文献
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120.
A. Goyal E. D. Specht D. M. Kroeger T. A. Mason D. J. Dingley G. N. Riley 《Journal of Electronic Materials》1995,24(12):1865-1868
The microstructure of high-Jc Bi-2223 powder-in-tube tapes was studied using x-ray and electron diffraction. Although the c-axis is nominally aligned perpendicular
to the tape surface (FWHM∼20‡), x-ray phi scans and pole figures show no evidence of any in-plane texture, either macroscopically
or locally. Electron backscatter diffraction patterns acquired in a scanning electron miscroscope (SEM) were used to measure
individual grain orientations. Grain boundary misorientation between adjacent grains was described by rotation angles and
axes (i.e. the disorientation) and compared with theoretical values of ideal coincidence site lattices (CSLs). Data collected
from over 113 spatially correlated grains resulting in 227 grain boundaries, show that over 40% of the boundaries are small
angle. In addition, 8% of the boundaries were found to be within the Brandon criterion for CSLs (larger than ⌆1 and less than
⌆50). Grain boundary “texture maps” derived from the SEM image and orientation data reveal the presence of percolative paths
between low energy boundaries. 相似文献