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231.
Effects of instructions on an individual's verbal behavior 总被引:1,自引:0,他引:1
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235.
A. Caicedo C. Cuevas G.M. Mophou G.M. N’Guérékata 《Journal of The Franklin Institute》2012,349(1):1-24
We prove in this paper the existence and uniqueness of mild solutions to some functional differential and functional integro-differential equations with infinite delay in Banach spaces which approach almost automorphic functions at infinity. We also discuss the existence of S-asymptotically mild solutions. The results are new. 相似文献
236.
作为我国基础研究"国家队"的重要组成部分,联合型SKL已经成为我国开展高水平基础研究的重要基地,但其原始创新和集成创新能力有限,且不同类型的联合型SKL自主创新绩效差异显著。首次运用SWOT法对我国联合型SKL自主创新进行了比较全面系统的分析。研究表明,我国联合型SKL在自主创新方面具有各自的优势和劣势,面临不同的威胁和发展的机遇。因此,发挥多种策略的协同功能,就成为提升我国联合型SKL自主创新能力的应对之策。 相似文献
237.
Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively. 相似文献
238.
Alberta Silvestri Serena Tonietto Francesco D’Acapito Gianmario Molin 《Journal of Cultural Heritage》2012,13(2):137-144
This work reports mainly the results of an X-ray Absorption Spectroscopy (XAS) study carried out on coloured glass tesserae from the palaeo-Christian mosaic which decorated the votive chapel of St. Prosdocimus (Padova) until its replacement with the current frescoes of Renaissance age, and which is one of the only two known mosaics in the Veneto region (Italy). The study aims at clarifying how the different local structure, oxidation state and quantity of copper influenced colour. Analysis of high-resolution Cu-K edge X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) spectra showed that copper is present as cuprite (Cu2O) in orange samples and as metallic copper in red and brown ones. These phases are responsible for both the colour and opacity of the samples. In addition, Cu1+ ions linked to the oxygen atoms of the glass framework were identified in ratios of about 60% and 30% of total copper in orange and red/brown samples, respectively. In blue and green samples, copper is dispersed in the glass matrix as a mixture of Cu1+ and Cu2+ ions, and no crystalline phases are visible. In this context, the Cu1+ and Cu2+ contents in glass were also quantified thanks to suitable standards, demonstrating that, when Cu2+ is the main chromophorous ion, colour intensity is directly correlated to its content in the glass. In particular, in green and blue samples, coloured by copper, Cu2+ content varies from 26% to 56% of total copper, and the higher contents of Cu2+ are shown by more intensely coloured samples. It should be stressed here that the green colour of the analysed tesserae is given by the physical interaction of blue colour, due to Cu2+ ions, and yellow colour, due to Pb antimonates used as opacifiers. 相似文献
239.
D. A. Kuz’mina 《Scientific and Technical Information Processing》2010,37(3):207-216
Questions about the construction of linguistic tools of an integrated databank on geology on a unified basis considering the
polydisciplinarity and comparison of generally adopted information retrieval languages are examined. A system model of thematic
classification for the integration of heterogeneous geological information on the basis of research problems is offered. Using
the example of the common rubricators at the bibliographic (VINITI rubricator of the Russian Academy of Sciences) and factographic
levels (VSEGEI dictionaries) generalized models are presented, viz., the organization of a thematic polydisciplinary space,
the integration of geoecological data, and the thematic classifications of radiogeological data, volcanic danger, and mineralogical-planetological
subjects. 相似文献
240.
Efficient algorithms for ranking with SVMs 总被引:1,自引:0,他引:1
RankSVM (Herbrich et al. in Advances in large margin classifiers. MIT Press, Cambridge, MA, 2000; Joachims in Proceedings
of the ACM conference on knowledge discovery and data mining (KDD), 2002) is a pairwise method for designing ranking models.
SVMLight is the only publicly available software for RankSVM. It is slow and, due to incomplete training with it, previous
evaluations show RankSVM to have inferior ranking performance. We propose new methods based on primal Newton method to speed
up RankSVM training and show that they are 5 orders of magnitude faster than SVMLight. Evaluation on the Letor benchmark datasets
after complete training using such methods shows that the performance of RankSVM is excellent. 相似文献