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291.
静电驱动悬臂梁数模转换器设计、分析与模拟 总被引:1,自引:0,他引:1
提出了一种新型的微电子机械数模转换器 (MEMDAC)———静电驱动悬臂梁数模转换器 .与传统的静电驱动悬臂梁执行器相比 ,新的结构能更精确地控制梁的挠度 .文中给出了此MEMDAC的设计、分析和模拟过程 .有限元(FEA)分析表明此MEMDAC的最大输出位移为 1 5 1μm ,分辨率为 0 1μm ,其最大非线性误差为 0 0 3μm . 相似文献
292.
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
293.
294.
295.
Shams-Zadeh-Amiri A.M. Xun Li Wei-Ping Huang 《Quantum Electronics, IEEE Journal of》2003,39(9):1086-1098
Radiation patterns of scattered fields with arbitrary azimuthal orders in multilayer planar waveguides and laser cavities with circularly symmetric gratings are formulated based on the volume current method. Full-wave Green's function analysis based on the integral transform method lies at the heart of this approach. Unlike the conventional approach, the dyadic Green's function relates some auxiliary fields to some auxiliary sources in the spectral domain. These auxiliary functions are defined to facilitate the spectral domain formulation in the cylindrical coordinate system and the use of transfer matrix method for obtaining a closed-form solution of the spectral Green's function in multilayer planar structures. More importantly, it is shown that the far-field pattern of the scattered field can be expressed directly in terms of the auxiliary fields in the Hankel transform domain. 相似文献
296.
微波功率放大器预失真线性化技术分析 总被引:2,自引:2,他引:0
给出了两种基本形式的预失真线性化电路,对其工作原理和技术特点进行了分析。 相似文献
297.
Huang J.C. Newell S. Galliers R.D. Shan-Ling Pan 《Engineering Management, IEEE Transactions on》2003,50(1):89-99
This paper presents an exploratory case study of the investment banking arm of a multinational banking corporation (Invebank) and its attempt to introduce component-based development (CBD). Based on a logic of opposition and utilizing literature on organizational culture and metaphors as an analytical device, issues confronting Invebank in CBD adoption are identified. In particular, problems in CBD implementation were encountered because, while CBD requires extensive knowledge sharing and collaboration, subcultural differences in Invebank meant that this proved difficult to enact. Thus, the paper considers the complexities of subcultural differences in firms and provides a salutary reminder that the implementation of corporate-wide integrative "solutions" such as CBD, may be problematic. Further, there is more to the issue of organizational subcultural differences than the oft-cited business-information technology (IT) divide. Nevertheless, the case demonstrates that subcultural differences should not simply be viewed as a threat. Rather, the recognition and discussion of these differences can provide a stimulus for identifying limitations of the policies surrounding technology implementation and use that if changed could help to maximize the benefits of the technology. Simplistic entreaties to knowledge sharing and the nurture of collaboration and consensus are, thus, brought into question. Implications for further research into the implementation of integrative software solutions like CBD in multifunctional and multifarious organizations are also considered. 相似文献
298.
Chengju Huang 《The Journal of communication》2003,53(3):444-459
Wilbur Schramm's "Soviet" communist model and J. Herbert Altschull's "Marxist" approach have been widely used as general theoretical frameworks to examine press systems in the Marxist world in general and China in particular. Though a growing literature suggested significant changes in Chinese journalism in the past 2 decades, very few studies have sent a direct challenge to the 2 models' theoretical wisdom through the Chinese case. This article finds neither of the 2 models is sufficient in conceptualizing the Chinese case because of Chinese news media's transitional nature and the 2 models' inner theoretical flaws as normative press theories. Furthermore, realizing the growing conflict between normative media theories and accelerated post-Cold War global media transformation, the author suggests using a transitional media approach to revisit the traditional normative media approach and calls for a more systematic study of the transitional phenomenon of global media systems. 相似文献
299.
谢家麟 庄杰佳 黄永章 张令翊 林绍波 赵春农 李立华 吴钢 王钢 李承泽 傅恩生 苏憬 钟元元 王言山 李永贵 应润杰 杨学平 李有猛 韩斌 吴庆武 张玉珍 潘卫民 王建伟 张黎文 郭康柱 畅祥云 李亚南 戴立盛 徐金强 陆辉华 汪伯嗣 任廉重 田瑞生 《中国物理 C》1994,18(8):763-768
北京自由电子激光(BFEL)装置于1993年底在10.68μm处实现了饱和振荡.输出激光能量为3mJ,饱和平顶宽度2μs.对应饱和振荡平均功率为210kW(宏脉冲),峰值功率约为20MW,比自发辐射高8个量级,单程小讯号净增益为24%,转换效率为0.45%,与理论预期结果相符.光束质量接近衍射极限.目前装置可工作于9-11μm. 相似文献
300.
给出了有两层基片的微带线与频率有关的混合模分析,应用傅里叶交换域分析及新的矩阵研究推导出色散特性.除了波导波长以外,还根据功率一电流的定义计算了特征阻抗,波导波长和特征阻抗与频率的关系及其数据值结果,并将其与有关文献的结果相比较,其一致性很好. 相似文献