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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
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Thompson M.G. Marinelli C. Tan K.T. Williams K.A. Penty R.V. White I.H. Kaiander I.N. Sellin R.L. Bimberg D. Kang D.-J. Blamire M.G. Visinka F. Jochum S. Hansmann S. 《Electronics letters》2003,39(15):1121-1122
Hybrid modelocking of monolithic quantum dot lasers is reported for the first time. A marked performance improvement over passive modelocking is demonstrated. Both hybrid and passive modelocking at /spl sim/10 GHz are achieved for the first time in quantum dot lasers. 相似文献
147.
148.
Wu D Tan DM Baird M DeCampo J White C Wu HR 《IEEE transactions on medical imaging》2006,25(3):335-344
A novel perceptually lossless coder is presented for the compression of medical images. Built on the JPEG 2000 coding framework, the heart of the proposed coder is a visual pruning function, embedded with an advanced human vision model to identify and to remove visually insignificant/irrelevant information. The proposed coder offers the advantages of simplicity and modularity with bit-stream compliance. Current results have shown superior compression ratio gains over that of its information lossless counterparts without any visible distortion. In addition, a case study consisting of 31 medical experts has shown that no perceivable difference of statistical significance exists between the original images and the images compressed by the proposed coder. 相似文献
149.
This paper presents a novel approach for transient and distortion analyses for time-invariant and periodically time-varying
mildly nonlinear analog circuits. Our method is based on a frequency domain Volterra series representation of nonlinear circuits.
It computes the nonlinear responses using a nonlinear current method that recursively solves a series of linear Volterra circuits
to obtain linear and higher-order responses of a nonlinear circuit. Unlike existing approaches, where Volterra circuits are
solved mainly in the time domain, the new method solves the linear Volterra circuits directly in the frequency domain via
an efficient graph-based technique, which can derive transfer functions for any large linear network efficiently. As a result,
both frequency domain characteristics, like harmonic and intermodulation distortion, and time domain waveforms can be computed
efficiently. The new algorithm takes advantage of identical Volterra circuits for second- and higher-order responses, which
results in significant savings in driving the transfer functions. Experimental results for two circuits—a low-noise amplifier
and a switching mixer—are obtained and compared with SPICE3 to validate the effectiveness of this method. 相似文献
150.
A novel ISI-free pulse is presented that has smaller maximum distortion, a more open receiver eye, and a smaller probability of error in the presence of symbol timing error than the Nyquist pulse for the same excess bandwidth 相似文献