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201.
Ban-Leong Ooi Dao-Xian Xu Pang-Shyan Kooi Fu-jiang Lin 《Microwave Theory and Techniques》2002,50(9):2202-2206
Based on an earlier study by Kuhn and Ibrahim (see IEEE J. Trans. Microwave Theory Tech., vol. 49, no. 1, p. 31-38, 2001) on current crowding, an improved expression incorporating the skin effect for the prediction of series resistance in spiral inductor modeling has been derived. A modified model for the spiral inductor, which accounts for the eddy-current effect, is thus proposed. Relatively good agreements between the measured data and the results generated from the model are obtained 相似文献
202.
Jie Xu 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(9):1789-1800
Alternative formulas for the dyadic Green's function in a rectangular waveguide are presented. These new functions are deduced by modifying part of Rahmat-Samii's derivation procedures by employing the Poisson summation technique. The Green's function obtained owns fast convergence property and is proved to be more suitable for numerical applications. 相似文献
203.
204.
High dielectric constant (high-k) polymer composites are of great interest for embedded capacitor applications. Previously,
we demonstrated that epoxy—aluminum composites are promising for embedded capacitor applications, because they have a high
dielectric constant and a low dielectric loss due to the core—shell structure of the self-passivated aluminum particles. In
this work, to further understand the dielectric behavior of aluminum composites, lower-loss polymers such as silicone, polyimide,
polynorbornene, and benzocyclobutene were explored as matrices for the aluminum composites. It is found that the polymer matrices
can significantly change the dielectric properties of the aluminum composites. A polymer matrix with a lower dielectric constant
generally results in a lower dielectric constant of its aluminum composites. In this regard, polymer—aluminum composites have
a similar dielectric characteristic as polymer—ceramic composites. Thermomechanical properties of aluminum composites were
characterized by a thermomechanical analyzer. 相似文献
205.
In this paper we propose a new protocol called time-space label switching protocol (TSL-SP) in optical burst switching (OBS), and define the terms time-space label (TSL) and time-space routing (TSR). An important concept of response time is introduced in the time label mechanism. The TSL-SP is a new technology that can quickly and efficiently forward data with a label on the optical networks. A two-dimension label switched path (TD-LSP) can be set up, that is maintained and deleted by the TSL-SP. For clearly illuminating the operation principles of the TSL-SP, we propose a new approach of orthogonal time-space coordinates in which the vertical coordinate is the space label and the horizontal coordinate is the time label. The proposed TD-LSP can dramatically reduce the routing failure probability and greatly improve the link network efficiency compared with other signaling protocols. Moreover, we define the time-space label control plane that can achieve the higher efficiency. When the TSL-SP is applied to networks, switching performance can be improved by two orders compared to the switching performance with the conventional OBS signaling protocols. The fundamental goal of TSL-SP is to band the signaling and routing functions together closely. Also, the TSL-SP can reduce the complexity of the network, support automatic service offering, and provide traffic engineering. 相似文献
206.
本文提出了一种快速远场近似(FAFFA)加速的混合物理光学矩量法(POMM),利用FAFFA加速计算矩阵方程中的矩阵矢量积,明显提高了计算效率.对物体表面上的远场组之间的耦合作用推导出了一组简洁的计算公式,并分析了计算复杂度.复杂金属组合体上线天线输入导纳、互导纳和方向性图的计算结果与文献结果一致.利用该方法分析计算了一个舰船模型上线天线的电磁特性.数值结果表明了这种方法的正确性和工程应用中的有效性. 相似文献
207.
本详细描述了移动IP的工作过程,并介绍了移动IP的隧道技术和IPSec,最后对移动IP技术中存在几个热点问题进行了讨论。 相似文献
208.
基于媒体用户访问行为偏好模型的代理缓存算法 总被引:2,自引:0,他引:2
目前,代理缓存技术广泛应用于改善流媒体传输的服务质量.文章从实际用户日志文件的分析出发,利用发现的用户浏览流媒体对象时的行为分布模型,提出了一种新的视频流媒体缓存算法.仿真结果证明,该算法可以通过记录很少的用户访问信息获取较高的性能表现. 相似文献
209.
核心通信网的光分组交换 总被引:1,自引:0,他引:1
文章首先简单说明了新一代通信网需要使用分级交换的由来。接着详细叙述了光分组交换在未来光通信网的应用,包括节点结构、分组格式、输入、输出接口和一些特别重要的技术,如再生、同步、信头处理、缓冲、空间交换和波长转换等。 相似文献
210.
T. Xu J. Stevens J.A. Villa J.T. Goldbach K.W. Guarini C.T. Black C.J. Hawker T.P. Russell 《Advanced functional materials》2003,13(9):698-702
Thin films of block copolymers have been used as templates and scaffolds for the fabrication of arrays of nanostructured materials. In general, a chemical modification of the film or the removal of one of the components by photodegradative methods is required to produce a nanoporous film that serves as a template or scaffold. Here, however, the preferential interaction of one of the components with a solvent is shown to produce a reconstruction of the block copolymer film that, upon drying, leads to the generation of a nanoporous template. The area density of the pores is identical to that of the original copolymer thin film. Since no chemical reactions occurr, the process is fully reversible. Upon heating the copolymer film above its glass‐transition temperature, mobility is imparted to the copolymer and the original copolymer film with oriented domains is recovered. The film reconstruction significantly simplifies the generation of nanoporous templates. 相似文献