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31.
交叉语言信息检索研究进展 总被引:2,自引:0,他引:2
Web上多种语言描述的信息形成“信息过载”,如何在传统的单语言信息检索技术的基础上开展对交叉语言信息检索的研究已经成为一项重要的研究课题。交叉语言信息检索的特殊性,给用户理解带来不少的困惑,同时缺乏完整的技术分析。该文全面分析了信息检索系统的原理和交叉语言信息检索系统的特殊技术。 相似文献
32.
33.
冯志伟 《术语标准化与信息技术》2007,(3):39-43
本文介绍了机器翻译发展的曲折过程,特别是介绍了世界上第一次机器翻译试验的许多鲜为人知的历史资料,说明了机器翻译对于语言学研究提出的各种新问题。 相似文献
34.
以现有通信网络平台PLMN(陆基移动通信网)和PSTN(公用电话交换网)的成熟技术为基础,实现电器设备的远程控制。主要以常见双音多频解码集成电路MT8870为核心,通过个人通信终端,以PLMN与PSTN通信网作为传输介质,以DTMF双音多频信号、振铃信号、回铃音信号等作为系统控制命令,对多路电器设备实现实时远程控制。 相似文献
35.
利用泛克里格方法消除MT噪音 总被引:2,自引:1,他引:1
对大地电磁测深(MT)资料,计算其变差函数;对这些变差函数进行回归分析,求得理论模拟变差函数;然后用泛克里格法估计大地电磁场信号,达到消除电磁场信号噪音的目的。通过实际资料的应用,效果比较理想。 相似文献
36.
以雄性昆明种小鼠为实验对象,连续服用褪黑激素(MT)51d建立动物模型。分别测试血红蛋白(Hb)含量、血清谷丙转氨酶(SGPT)活性、血清谷草转氨酶(SGOT)活性、超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量与总抗氧化能力(T-AOC)。结果表明,连续服用MT后,对小鼠Hb含量、肝SOD活性及SGOT活性无显著性影响(P>0.05),可使SGPT活性、血清及肝MDA含量显著下降(P<0.01)。肝T-AOC明显升高(P<0.05)。实验结果提示,MT具有很强的抗氧化能力,对机体的抗氧化系统有明显的辅助作用。 相似文献
37.
N. Droushiotis F. Dal Grande M. H. Dzarfan Othman K. Kanawka U. Doraswami I. S. Metcalfe K. Li G. Kelsall 《Fuel Cells》2014,14(2):200-211
Two types of micro‐tubular hollow fiber SOFCs (MT‐HF‐SOFCs) were prepared using phase inversion and sintering; electrolyte‐supported, based on highly asymmetric Ce0.9Gd0.1O1.95(CGO) HFs and anode‐supported based on co‐extruded NiO‐CGO(CGO)/CGO HFs. Electroless plating was used to deposit Ni onto the inner surfaces of the electrolyte‐supported MT‐HF‐SOFCs to form Ni‐CGO anodes. LSCF‐CGO cathodes were deposited on the outer surface of both these MT‐HF‐SOFCs before their electrochemical performances were compared at similar operating conditions. The performance of the anode‐supported MT‐HF‐SOFCs which delivered ca. 480 mW cm–2 at 600 °C was superior to the electrolyte‐supported MT‐HF‐SOFCs which delivered ca. six times lower power. The contribution of ohmic and electrode polarization losses of both FCs was investigated using electrochemical impedance spectroscopy. The electrolyte‐supported MT‐HF‐SOFCs had significantly higher ohmic and electrode polarization ASR values; this has been attributed to the thicker electrolyte and the difficulties associated with forming quality anodes inside the small (<1 mm) lumen of the electrolyte tubes. Further development on co‐extruded anode‐supported MT‐HF‐SOFCs led to the fabrication of a thinner electrolyte layer and improved electrode microstructures which delivered a world leading 2,400 mW cm–2. The newly made cell was investigated at different H2 flow rates and the effect of fuel utilization on current densities was analyzed. 相似文献
38.
A.V. Kuznetsov 《International Communications in Heat and Mass Transfer》2011,38(10):1317-1321
This paper is motivated by recent experimental research that demonstrated pharmacological efficiency of axonal transport drug delivery. The purpose is to develop a model of this process and to study how the rate of destruction of pharmaceutical agent complexes (PACs) affects their transport in the axon. The model includes two populations of PACs: PACs in the state when they are driven retrogradely (from the axon terminal toward the neuron soma) by dynein motors and PACs residing in the accumulated state (but can still be re-released to the dynein-driven state). The coupling between the kinetic states is accounted for by first-order reactions. Utilizing Laplace transform, analytical solutions for concentrations of these two populations of PACs are obtained. The effect of PAC destruction is investigated for different values of other parameters. It is shown that the shapes of the waves describing the PAC concentrations can be significantly affected by transport parameters. 相似文献
39.
Tamar Opher 《The Science of the total environment》2009,407(15):4490-4496
Pollutants accumulated on road pavement during dry periods are washed off the surface with runoff water during rainfall events, presenting a potentially hazardous non-point source of pollution. Estimation of pollutant loads in these runoff waters is required for developing mitigation and management strategies, yet the numerous factors involved and their complex interconnected influences make straightforward assessment impossible. Data-driven models (DDMs) have lately been used in water and environmental research and have shown very good prediction ability. The proposed methodology of a coupled MT-GA (model tree-genetic algorithm) model provides an effective, accurate and easily calibrated predictive model for EMC (event mean concentration) of highway runoff pollutants. The models were trained and verified using a comprehensive data set of runoff events monitored in various highways in California, USA. EMCs of Cr, Pb, Zn, TOC and TSS were modeled, using different combinations of explanatory variables. The models' prediction ability in terms of correlation between predicted and actual values of both training and verification data was mostly higher than previously reported values. Sensitivity analysis was performed to examine the relative significance of each explanatory variable and the models' response to changes in input values. 相似文献
40.
DTMF信号收、发芯片 MT8888原理及应用 总被引:6,自引:0,他引:6
MT8888芯片是MITEL公司采用CMOS工艺生产的一种低功耗、高集成度的DTMF信号收、发芯片,它可方便地与微机接口。文中介绍了MT8888的主要功能结构及控制指令,给出了它的具体应用电路。 相似文献