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911.
Iñigo Navarro Antonio J. López-Martín Carlos A. de la Cruz Alfonso Carlosena 《Analog Integrated Circuits and Signal Processing》2004,41(2-3):159-166
A compact, four-quadrant analog CMOS multiplier featuring wide dynamic range is presented. The capacitive voltage division obtained by the use of Floating-Gate MOS (FGMOS) transistors, and an accurate wide-swing current mirror based on active bootstrapping, allow a wide input range, low harmonic distortion, and high linearity. Simulation and measurement results for a 0.8 μm CMOS prototype demonstrate the validity of the proposed approach. 相似文献
912.
913.
The abstract (or semantic) syntax of the Pascal language is identified, and a linear representation for the trees so formed within the framework of the concrete syntax for that language is imposed. The indentation scheme so formed, augmented with a small number of pragmatic considerations, is compared with several previously proposed formatting schemes for Pascal and an example of the use of this new method is given. 相似文献
914.
Jesús García-Cantalejo Victoriano Baladrn Pedro F. Esteban M. Angeles Santos Germn Bou Miguel A. Remacha Jos L. Revuelta Juan P. G. Ballesta Antonio Jimnez Francisco Del Rey 《Yeast (Chichester, England)》1994,10(2):231-245
We report the sequence of an 18,002 bp DNA fragment from the right arm of Saccharomyces cerevisiae chromosome XI. This segment contains nine complete open reading frames (ORFs), YKR401 to YKR409, and part of another ORF, YKR400, covering altogether 87·2% of the entire sequence. One of them, YKR400, encodes an NAD-dependent 5,10-methylene-tetrahydrofolate dehydrogenase. YKR404, YKR405 and YKR406 correspond to the previously characterized HBS1, MRP-L20 and PRP16 genes, coding for a translation elongation factor, a mitochondrial ribosomal protein and an ATP-binding protein, respectively. The putative product of YKR407 contains the zinc-binding region signature of neutral zinc metallopeptidases. The five other ORFs do not show significant homology to any known protein. The sequence data reported here have been assigned EMBL accession number Z27116. 相似文献
915.
RJ Ippolito 《Canadian Metallurgical Quarterly》1993,57(7):451-455
A variation of Mirizzi's syndrome is described in which common hepatic duct obstruction occurs due to extrinsic compression by an acutely inflamed acalculous gallbladder abutting the common hepatic duct. This case suggests that extrinsic compression and inflammation in the absence of stones can result in complete obstruction of extrahepatic biliary flow. 相似文献
916.
917.
The supermolecular structure of crystallised molecular weight fractions of poly(hexa-methylene oxide), covering the molecular weight range (M) 4.5. × 103 to 8. 5 × 104, was studied by polarised light microscopy and small angle light scattering. Different forms were observed as a function of molecular weight and crystallisation temperatures. Perfect spherulites are formed after rapid crystallisation, and these forms deteriorate as both the molecular weight and crystallisation temperature increase. The morphology in the isothermal crystallisation region corresponds to an intermediate state which represents a transition from spherulites to hedrites. 相似文献
918.
This paper describes the theoretical background and the process of obtaining maximum hop lengths and minimum fading margins (if the terminal or repeater locations are fixed) in any region of the world and gives a set of curves providing these characteristics for 1 km with availability of 99.7 % of the time (per 2 500 km), for a given frequency and polarization. Correction factors for other availabilities are also given. 相似文献
919.
Antonio Gonzalez 《国际智能系统杂志》1995,10(4):357-371
A step-by-step methodology for learning fuzzy rules is presented. This methodology tries to be general enough to give a framework within which different learning methods in an environment of uncertainty and imprecision could be developed. the final product will always be an uncertainty distribution on the different rules representing the behavior of the system. the particular uncertainty distribution depends on the concrete functions selected in each step of the process. the learning approach can also be considered as a way to construct uncertainty measures from data. © 1995 John Wiley & Sons, Inc. 相似文献
920.