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991.
In this paper, we describe the design, fabrication, and bench study of a millimeter-wave cavity employed as a relativistic klystron output structure. The oxygen-free electronic-grade copper cavity was prepared by electro-discharge machining and diffusion bonding, and cleaned and tuned to 91.4 GHz. Measured cavity characteristics are presented and compared with theory, including quality factor Q, coupling parameter β, scattering matrix S11, and axial electric field profile Ez. This paper provides the basis for an understanding of the cavity as a transfer structure  相似文献   
992.
This paper presents a novel approach for low-power high-performance inner product processor design. The processor is dynamically reconfigurable for computing inner products of input arrays with four or more combinations of array dimensions and precision. The processor mainly consists of an array of 8×8 or 4×4 small multipliers plus two or three arrays of adders. It requires very simple reconfigurable components. The whole network may be reconfigured by using a few control bits for the desired computations, and the reconfiguration can be done dynamically. The design is regular, modular, and can easily be pipelined, and most parts of the network are symmetric and repeatable. A set of low-power high-performance parallel counters is also proposed for the implementation of the design, which could lead to a significant reduction in worst case power dissipation compared with traditional binary-logic based architectures, while showing superiority in speed, VLSI area, and layout simplicity  相似文献   
993.
Via-free broadband microstrip to CPW transition   总被引:1,自引:0,他引:1  
Lin  T.-H. 《Electronics letters》2001,37(15):960-961
A broadband microstrip to coplanar waveguide (CPW) transition is proposed. The design is based on vertical resonant coupling between the microstrip and CPW. The transition does not require via holes, wire bonds, or air bridges. The design of the transitions at C band shows good agreement with return loss better than -15 dB over 2.8-7.5 GHz. The new transition has the advantages of broad bandwidth and easy fabrication  相似文献   
994.
Admission control in time-slotted multihop mobile networks   总被引:4,自引:0,他引:4  
The emergence of nomadic applications have generated a lot of interest in next-generation wireless network infrastructures which provide differentiated service classes. So it is important to study how the quality of service (QoS), such as packet loss and bandwidth, should be guaranteed. To accomplish this, we develop am admission control scheme which can guarantee bandwidth for real-time applications in multihop mobile networks. In our scheme, a host need not discover and maintain any information of the network resources status on the routes to another host until a connection request is generated for the communication between the two hosts, unless the former host is offering its services as an intermediate forwarding station to maintain connectivity between two other hosts. This bandwidth guarantee feature is important for a mobile network to interconnect wired networks with QoS support. Our connection admission control scheme can also work in a stand-alone mobile ad hoc network for real-time applications. This control scheme contains end-to-end bandwidth calculation and bandwidth allocation. Under such a scheme, the source is informed of the bandwidth and QoS available to any destination in the mobile network. This knowledge enables the establishment of QoS connections within the mobile network and the efficient support of real time applications. In the case of ATM interconnection, the bandwidth information can be used to carry out an intelligent handoff between ATM gateways and/or to extend the ATM virtual circuit service to the mobile network with possible renegotiation of QoS parameters at the gateway. We examine via simulation the system performance in various QoS traffic flows and mobility environments  相似文献   
995.
郭效辉  林立 《广东通信技术》2001,21(3):26-27,31
随着波分复用技术在传输网络上的进一步应用,对波分复用系统的维护和故障处理成了广大维护人员关心的重点,本文主要以实际的例子探讨了维护和排障工作的方法和要点,为日常工作提供参考。  相似文献   
996.
Journal of Signal Processing Systems - With the latest development of automation technology, object detection technology has received more and more research attention. Automated object detection...  相似文献   
997.
风格迁移过程中风格元素均匀分布在整个图像中会使风格化图像细节模糊,现有的迁移方法主要关注迁移风格的多样性,忽略了风格化图像的内容结构和细节信息.因此,该文提出结构细化的神经风格迁移方法,通过增加边缘检测网络对内容图像的轮廓边缘进行提取实现风格化图像内容结构的细化,凸显内容图像中的主要目标;通过对转换网络中的常规卷积层的...  相似文献   
998.
Itaconate (ITA) is an emerging powerhouse of innate immunity with therapeutic potential that is limited in its ability to be administered in a soluble form. A library of polyester materials that incorporate ITA into polymer backbones resulting in materials with inherent immunoregulatory behavior is developed. Harnessing hydrolytic degradation release from polyester backbones, ITA polymers result in the mechanism specific immunoregulatory properties on macrophage polarization in vitro. In a functional assay, the polymer-released ITA inhibits bacterial growth on acetate. Translation to an in vivo model of biomaterial associated inflammation, intraperitoneal injection of ITA polymers demonstrate a rapid resolution of inflammation in comparison to a control polymer silicone, demonstrating the value of sustained biomimetic presentation of ITA.  相似文献   
999.
本文跟踪了信息安全及客户信息安全相关标准的进展,并重点对客户信息安全保护的相关标准进行了全面解读,提出需要技术管理相结合的方式对运营商企业的客户信息进行全面保护的方案。  相似文献   
1000.
采用半导体激光器(LD)端面抽运声光调Q的Nd:YVO4激光器做为抽运源,选用周期性极化掺氧化镁铌酸锂晶体(PPMg LN),通过优化抽运光光束质量和模式匹配,获得了中红外光参变振荡器。实验发现,对于确定的LD抽运功率,当重复频率较小,输出功率随着重复频率的增加而增加,但是达到某一重复频率时,输出功率便随着重复频率的增加而减少。改变PPMg LN晶体的周期,实现了中红外2.95~4.16 mm宽带调谐。  相似文献   
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