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71.
Design of a 3780-point IFFT processor for TDS-OFDM 总被引:2,自引:0,他引:2
Zhi-Xing Yang Yu-Peng Hu Chang-Yong Pan Lin Yang 《Broadcasting, IEEE Transactions on》2002,48(1):57-61
This correspondence presents a design of 3780-point IFFT processor for TDS-OFDM terrestrial DTV transmitter using FPGA. It demonstrates the algorithm design and error analysis of the processor, which can achieve a throughput of 7.56M complex IFFT operations per second. This design meets the signal-to-quantization noise ratio requirement of the TDS-OFDM system. It consists of two FPGA and one dual-port RAM. The data stream pipeline algorithm is implemented 相似文献
72.
CASE与MIS的开发 总被引:1,自引:0,他引:1
本文介绍CASE技术的基本思想与构成,CASE工具在MIS开发中的作用,概要介绍国内流行的CASE产品并对其作出评述。 相似文献
73.
A novel and systematic method is presented for the complete determination of dyadic spectral Green's functions directly from Maxwell's equations. With the use of generalized scalarizations developed in this paper, four general and concise expressions for the spectral Green's functions for one-dimensionally inhomogeneous multilayer structures, excited by three-dimensional electric and magnetic current sources, are given in terms of modal amplitudes together with appropriate explicit singular terms at the source region. It is shown that Maxwell's equations in spectral-domain can be reduced, by using dyadic spectral eigenfunctions, to two sets of z-dependent inhomogeneous transmission-line equations for the modal amplitudes. One set of the transmission-line equations are due to the transverse current sources and the other set due to the vertical current sources. Utilizing these equations, network schematizations of the excitation, transmission and reflection processes of three-dimensional electromagnetic waves in one-dimensionally inhomogeneous multilayer structures are achieved in a full-wave manner. The determination of the spectral Green's functions becomes so simple that it is accomplished by the investigation of voltages and currents on the derived equivalent circuits. Examples of singleand multilayer structures are used to validate the general expressions and the equivalent circuits 相似文献
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75.
本文设计了一种应用于油气藏永久性实时动态监测系统。该系统用光纤Bragg光栅(FBG)传感器作为井下永久性传感器,测量目的层的温度、压力等参数的模拟信号;在井口建立数据采集处理系统,将模拟信号解调成数字信号;通过GPRS无线移动通信网络传输到监测中心的数据库服务器上,并以Web形式发布到Internet网络上,同时提供移动用户浏览接口,且当数据异常时可以发送报警短消息。该系统实现了油气藏的远程实时动态监测,可以为油藏管理人员和技术人员及时、准确地做出决策提供可靠依据。 相似文献
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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
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本文介绍了给水联合处理的原理及其优点以及在望亭电厂的1台300MW亚临界燃油直流炉上进行这项处理的工业性试验的过程、效果及存在问题。最后作者对给水联合处理能否取得成效的关键提出了意见。 相似文献
80.
大型石油化工企业供配电系统 总被引:2,自引:1,他引:1
根据大型石油化工企业供配电特点 ,介绍了石油化工企业内三种主要的供配电方式 ,并对其进行了较详细的分析比较 相似文献