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1.
Javier Ramírez Antonio García Uwe Meyer-Bäse Fred Taylor Antonio Lloris 《The Journal of VLSI Signal Processing》2003,33(1-2):171-190
Currently there are design barriers inhibiting the implementation of high-precision digital signal processing (DSP) objects with field programmable logic (FPL) devices. This paper explores overcoming these barriers by fusing together the popular distributed arithmetic (DA) method with the residue number system (RNS) for use in FPL-centric designs. The new design paradigm is studied in the context of a high-performance filter bank and a discrete wavelet transform (DWT). The proposed design paradigm is facilitated by a new RNS accumulator structure based on a carry save adder (CSA). The reported methodology also introduces a polyphase filter structure that results in a reduced look-up table (LUT) budget. The 2C-DA and RNS-DA are compared, in the context of a FPL implementation strategy, using a discrete wavelet transform (DWT) filter bank as a common design theme. The results show that the RNS-DA, compared to a traditional 2C-DA design, enjoys a performance advantage that increases with precision (wordlength). 相似文献
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分析了目前公用交换电话网(PSTN)中存在的问题和下一代网络(NGN)的优越性,分析了NGN中的关键技术媒体网关控制技术,探讨了媒体网关控制技术在Alcatel5020MGC中的实际应用,讨论了Alcatel5020MGC的软硬件系统架构。最后强调了在PSTN向NGN发展过程中基于演进产品的方法的重要性。 相似文献
3.
Z. Gruba? 《Materials Letters》2007,61(3):794-798
The initial stage of copper electrodeposition on the electrochemically activated assembly of carbon microelectrodes from an acid solution of copper sulfate was investigated using cyclic voltammetry, potentiostatic pulse technique and electrochemical impedance spectroscopy. Analysis of the experimental current transients has been carried out using a non-linear fitting procedure according to the model that takes into account spherical diffusion towards a disc-shaped microelectrode. The higher values of diffusion coefficient in comparison with those observed on planar electrodes were explained with an increased diffusion caused by the electrode geometry. Impedance spectra showed two time constants, the high-frequency related to the charge transfer process and the low-frequency corresponded to the deposit morphology. 相似文献
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Agnieszka J Klemm Piotr Klemm Kazimierz Rozniakowski Tomasz W Wojtatowicz 《Building and Environment》2002,37(12):1221-1232
This paper present the results of the investigation into a potential application of laser radiation for the detection of phase transition processes occurring on the surface layers of porous materials. An attempt was made to discuss in the approximation equations, the relationships between coefficients of the reflected light, the temperature and humidity of the surrounding environment. Laser light reflected from the porous surface carries information about the roughness of the structure. The presence of water microdrop on the surface of the porous material, as a result of condensation and thus a phase transition, leads to the phase displacement of individual rays, which is represented by different images. Therefore, a comprehensive analysis of the reflected light parameters allows a dynamic study of the phase transition phenomena without mechanical intervention. 相似文献
6.
Reviews the book, ILe choc de l'informatique: Les répercussions psychosociales et le r?le des attitudes by Serge Guimond and Guy Bégin (1987). This monograph is concise and easy to read. The reader knows immediately that technological questions will be explored, as well as the psychological and human questions being attached to the new use of information technology. Three fields are covered, each one the subject of a chapter: 1) computers in the educational circle; 2) computers and work; and 3) computers in the house. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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《Information & Management》2014,51(8):1031-1042
Customer relationship management (CRM) has become one of the most influential technologies in the world, and companies are increasingly implementing it to create value. However, despite significant investment in CRM technology infrastructure, empirical research offers inconsistent support for its positive impact on performance. This study develops and tests a research model analyzing the process through which CRM technology infrastructure translates into organizational performance, drawing on the resource-based view (RBV) and the knowledge-based view (KBV) of the firm. Based on an international sample of 125 hotels, the results suggest that organizational commitment and knowledge management fully mediate this process. 相似文献
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