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101.
102.
We present four techniques for modeling and animating faces starting from a set of morph targets. The first technique involves obtaining parameters to control individual facial components and learning the mapping from one type of parameter to another through machine learning techniques. The second technique is to fuse visible speech and facial expressions in the lower part of a face. The third technique combines coarticulation rules and kernel smoothing techniques. Finally, a new 3D tongue model with flexible and intuitive skeleton controls is presented. The results of eight animated character models demonstrate that these techniques are powerful and effective. 相似文献
103.
介绍了SPAC 315C馈线终端综合保护器在馈线端为6kV/0.4kV变压器线路中的实际运用,并阐述其主要功能和特点。 相似文献
104.
105.
Jing Li Jiyang Wang Huaijin Zhang Shouren Zhao Xiaoxia Wang 《Materials Research Bulletin》2004,39(9):1329-1334
Single crystal of erbium, ytterbium-codoped yttrium aluminum tetraborate Er,Yb:YAl3(BO3)4(Er,Yb:YAB) has been grown by the flux method. The absorption spectrum in the visible and NIR regions of Er,Yb:YAl3(BO3)4 crystal are measured at room temperature and fluorescence spectrum of Er,Yb:YAl3(BO3)4 crystal are also measured at room temperature, excited by 976 nm laser. Not only the strong NIR emission peaks located at 1548 nm was observed, but also the visible up-conversion luminescence has been found. The specific heat of the Er/Yb:YAB crystal at room temperature is 0.81 J/g °C. 相似文献
106.
L. Marchin 《Materials Research Bulletin》2004,39(12):1973-1983
This paper describes the synthesis of some thorium phosphate compounds with different Th/P ratio (1/2, 2/3 and 3/4) by a spray pyrolysis technique. The so-prepared rough compounds were annealed at different temperatures for 2 h and then analyzed by mainly X-ray diffraction on powder and infrared spectroscopy. Every rough compound is composed by very badly crystallized ThO2 phase polluted by carbon residue. An annealing treatment at 800 °C leads to the thorium diphosphate phase, α-ThP2O7 in every case. At 900 °C, such a phase is decomposed into a thorium phosphate diphosphate phase (Th4(PO4)4P2O7, called TPD). However, a thorium excess in the initial mixture (Th/P = 3/4) leads also to observe the ThO2 phase. The TPD phase is stable up to 1200 °C and does not react with the ThO2 compound. Beyond 1200 °C, the TPD phase is slowly decomposed into a thorium phosphate compound which should be a thorium oxide phosphate; this compound does not contain any diphosphate species. 相似文献
107.
H.P. Li 《Materials Research Bulletin》2004,39(12):1881-1894
Self-propagating high-temperature synthesis (SHS), or the so-called micropyretic/combustion synthesis, is a technique whereby a material is synthesized by the propagation of a combustion front across a powder. Heterogeneous distributions of porosities are common during self-propagating high-temperature synthesis when powders are pressed and the conventional modeling treatments thus far have only considered uniform systems. Heterogeneities in the porosity are thought to result in local variations of such thermophysical/chemical parameters for the reactants as density and thermal conductivity further changing the combustion temperature, the propagation velocity, and the propagation pattern of a combustion front. This study investigates the impact of porosity variations during self-propagating high-temperature synthesis with Ti + 2B. In addition, the simulations for the propagation of combustion fronts across a non-uniform compact where the porosity is monotonically decreased or increased along the specimens due to die wall friction are also carried out. 相似文献
108.
经测试得出,在临界[C]为0.2%~0.8%、供氧强度为定值时,脱碳速度主要取决于[C]向钢渣反应界面的扩散。70t UHP DC电弧炉脱碳实践表明,采用熔清后全程小角度吹氧,熔池沸腾良好后再喷碳粉造泡沫渣,渣碱度为2.0~2.5,避免形成低碱度泡沫渣,在临界[C]范围内进行通电脱碳操作,利用电路磁场搅拌作用,促进[C]向反应界面扩散,可避免大沸腾事故的发生。 相似文献
109.
针对传统的Run_Length压缩算法在应对极端数据时所遇到的问题,提出了改进极端数据影响的措施,采取调整计数长度和调整传统Run_Length算法的策略,不用特定字符作为压缩标志,而使用特殊字节位来用作压缩标志,并调整了区分计数字节和数据字节的方法,改进后的算法,大大提高了重复数据长度大于63和大于127的数据的压缩率,为Run_Length算法有针对性应用提供了改进方案,同时,给出了Run_Length压缩算法的C 程序代码。 相似文献
110.
介绍以AT89C2051单片机为核心的滚动式广告窗控制系统原理,并给出了超声波发射、接收电路,步进电机控制电路等硬件电路和软件结构流程图,该系统实现了静态广告画面旋转的自动控制,提高了广告宣传的效果。 相似文献