基于分类及最佳匹配读音的维吾尔多音词消歧

研究维吾尔语中的多音词现象,根据多音词的不同特点进行分类。利用词性和读音的映射关系消歧第1类多音词。根据词缀连接词干后是否发生元音弱化的特点消歧第2类多音词。提取上下文语境信息,使用最佳匹配读音的方法消歧第3类多音词。采用似然比方法进行关键词选择,并对不同窗口宽度的关键词选取方法进行对比实验。结果表明,该方法可以得到错误率为20.9%的多音词消歧效果。     

Effect of heat treatment and composition on the superconductivity in Pb-Sr-R-Ca-Cu-O oxide system

The effect of compositions, sintering temperatures and furnace atmospheres on the superconducting transition temperatures of several members of the series Pb₂Sr₂R_1−x Ca _x Cu₃O _z (0.0⩽x⩽0.7, R=Y, Gd) has been studied. The effect of partial replacement of Pb, Ca and Y by In has also been studied. The shapes of the resistivity-temperature curves and the zero resistance temperatures are found to be extremely sensitive to the synthesis parameters employed. Superconductivity is not observed in samples treated in oxidizing atmosphere or heated at very high temperatures. Samples sintered in flowing nitrogen showed incomplete transition in resistivity starting at about 75 K and extending down to 15 K. A new and comparatively simple synthesis procedure involving treatment of the samples in vacuum has been employed to obtain nearly single-phase materials showing metallic behaviour. Using this procedure, samples of the above composition, but containing no Ca(i.e. Pb₂Sr₂RCu₃O_z, R=Y and Dy), are also found to be superconducting with zero resistance up to 48 K.     

Interaction of synthetic polyampholytes with anionic and cationic detergents in aqueous solution

Summary The interaction of amphoteric macromolecules with ionic surfactants is accompanied by a strong decrease of the dimensions of the polyelectrolyte chains, but the complex particles are retained from precipitation by the presence of the hydrophylic components of the polyampholyte. The behaviour of the complex polyampholyte-detergent depends both on the nature of amphoteric copolymers and on the ionic detergents.     

TTS语音单元的无损压缩与按需解压缩技术

以波形拼接式维吾尔语音合成系统研发为背景,在已建立的维吾尔语最小发音单位音节和音素作为合成基元的语音库基础上,对语料库中的所有音节、音素进行无损压缩,选择了运算速度快,便于实现的哈夫曼压缩。在解压过程中只解压人们所需的语音单元,而不需要解压整个语料库。实验结果表明,通过哈夫曼压缩算法对语料库进行压缩和解压,减小了语料库的占用空间,同时解压后的语音不失真,解压速度快。     

基于自动机的喀什方言音位变化规则研究

从喀什方言维吾尔语音合成的实际需求出发,在对照文本语料库的基础上,对比分析从标准维吾尔语到喀什方言的音位对应关系,根据增音、减音、换音等变位现象,总结相应的音位变化规则,构造基于有限状态自动机的转换模型及算法.实验结果表明,基于规则的自动转换算法具有良好的运行效果.     

Synthesis and characterization of lanthanum strontium manganite

La_0.85Sr_0.15MnO₃ (LSM) powder has been prepared by co-precipitation. Phase evolution studies by DTA, TGA and XRD indicated initiation of LSM formation above 750 °C. Densification behaviour of LSM powder with and without pore former was different. Sintered LSM was characterized for electrical conductivity, thermal expansion and microstructural development.     

Nucleation sequence on the cation exchange process between Y0.95Eu0.05PO4 and CePO4 nanorods

Nanorods of Y0.95Eu0.05PO4@CePO4 (Y0.95Eu0.05PO4 phase was nucleated first and then a CePO4 phase was nucleated) and CePO4@Y0.95Eu0.05PO4 (CePO4 phase was nucleated first and then Y0.95Eu0.05PO4 phase was nucleated) were prepared at a relatively low temperature of 140 °C in ethylene glycol medium. Based on XRD, TEM and Raman studies it has been inferred that Y0.95Eu0.05PO4@CePO4 sample consists of a mixture of bigger (length around 800-1000 nm and width around of 80-100 nm) and smaller (length around 70-100 nm and width around 10-20 nm) nanorods, having monoclinic CePO4 and tetragonal YPO4 structure, whereas CePO4@Y0.95Eu0.05PO4 sample consists of mainly small nanorods having a single phase CePO4 structure. From the detailed luminescence studies it has been established that there exists significant incorporation of Y3+/Eu3+ ions in the CePO4 phase in CePO4@Y0.95Eu0.5PO4 sample. This has been attributed to the cation exchange taking place between Ce3+ ions in CePO4 host and Eu3+ and Y3+ ions in solution during the synthesis stage. Unlike this, such an exchange is not possible for Y0.95Eu0.05PO4@CePO4 sample synthesized under identical conditions due to the higher solubility product (Ksp) value of YPO4 compared to CePO4. Incorporation of Eu3+ in the CePO4 lattice of CePO4@Y0.95Eu0.5PO4 sample is confirmed by the significant reduction in the lifetime of 5D0 level of Eu3+ and the luminescence intensity from Eu3+, arising due to the electron transfer between the Ce3+/Ce4+ and Eu3+/Eu2+ species. These results are further supported by the non-radiative decay rates and quantum yields calculated from the emission spectrum.