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171.
硬件演化原理及实现方法研究 总被引:7,自引:4,他引:3
文章对基于Virtex系列FPGA的硬件外部演化技术进行了研究,对演化算法的流程进行了分析,介绍了演化硬件的概念、原理、JBits API软件以及Virtex器件结构。基于JBits软件,采用外部演化的方式对电路进行演化,并通过仿真实例证明了这种方法的有效性。 相似文献
172.
173.
174.
Split Plot Experiments: Taguchi's Ina Tile Experiment Reanalyzed 总被引:1,自引:0,他引:1
175.
1 INTRODUCTIONUltrafiltration(UF )isamembraneseparationprocesswhichhasfoundwideapplicationsinsuchfieldsaspetroleum ,textile ,bioseparation ,pharma cy ,food ,wastewatertreatment,preparationofdrinkingwater[13] .Manyresearchershavedevotedthemselvestoimprovingthe permeationfluxoftheUFmembraneunderthesamerejection ,andprevent ingtheformationofafoulinglayeronthesurfaceofUFmembrane .Manynovelmembranematerialsandvariousmodificationtechnologieshavebeendevel oped ,somemodificationmethods ,suchas… 相似文献
176.
MD Caversaccio P Zb?ren M Vischer H Tsch?ppeler 《Canadian Metallurgical Quarterly》1996,44(8):440-444
From 1989-1993 we performed rigid bronchoscopies in 86 children in whom foreign body aspirations were suspected. In 72 cases, foreign bodies were identified in the tracheobronchial tree. In the remaining 14, no foreign body was found. Boys outnumbered girls. The most common type of foreign body was a peanut. The predilection of the foreign body was to fall into the right main bronchus. If the history indicated foreign body aspiration, a chest x-ray was not found to be necessary except for forensic interest. 相似文献
177.
Nanzad Tsevegsüren Kurt Aitzetmüller 《Journal of the American Oil Chemists' Society》1996,73(12):1681-1684
Seeds of nine Central Asian species of Boraginaceae were investigated for the first time for their oil content and for the
fatty acid composition of their seed oils by capillary gas chromatography. Levels of γ-linolenic acid ranged from 6.6 to 13.0%
and levels of stearidonic acid ranged from 2.4 to 21.4% of total seed fatty acids. The seed oil ofHackelia deflexa exhibited the highest stearidonic acid content (21.4%) that has been found so far in nature. Other high contents of this
fatty acid were in threeLappula species (17.2 to 18.1%). Seed oils ofCynoglossum divaricatum andAmblynotus rupestris contain considerable amounts ofcis-11-eicosenoic (5.3 to 5.8%) andcis-13-docosenoic acid (7.0 to 9.7%) besides γ-linolenic (10.2 to 13.0%) and stearidonic acid (2.4 to 6.5%), which distinguish
these oils from those of other Boraginaceae genera.
This paper was presented as a poster at 10th Minisymposium and Workshop on Plant Lipids, Sept. 3–6, 1995, in Berne, Switzerland. 相似文献
178.
Mutual exclusion and general synchronization of concurrent processes (‘tasks’) are well-known principles for constructing reliable real-time systems. This paper shows how to implement these principles under a typical commercial operating system which provides incomplete synchronization operations. The problem of synchronizing erroneous tasks is discussed briefly. 相似文献
179.
180.
A number of different surface chemistries have been developed in recent years to render semiconductor nanocrystals (NCs) stable in water and biocompatible. However, most of these surface modifications affect NCs' photophysical properties, calling for a method to simultaneously monitor colloidal and fluorescence properties. Fluorescence correlation spectroscopy (FCS) combined with ensemble spectroscopic methods and Monte Carlo simulations were used to interpret and derive photophysical as well as colloidal properties of four different NC surface treatments. Using a novel FCS scheme with alternating laser excitation at two different intensities, we first ruled out influences from optical gradient forces (optical trapping). We then compared concentration of emitting particles, brightness per particle, saturation intensity, blinking (intermittency), hydrodynamic radius, and propensity for aggregation of the different bioconjugated NCs. This approach was successfully applied during the development and optimization of peptide-coated NCs. 相似文献