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71.
This study investigated macroscopic inhomogeneous deformation occurring in single-crystal Ni–Mn–Ga foils under uniaxial tensile loading. Two types of single-crystal Ni–Mn–Ga foil samples were examined as-received and after thermo-mechanical training. Local strain and the strain field were measured under tensile loading using laser speckle and digital image correlation. The as-received sample showed a strongly inhomogeneous strain field with intermittence under progressive deformation, but the trained sample result showed strain field homogeneity throughout the specimen surface. The as-received sample is a mainly polycrystalline-like state composed of the domain structure. The sample contains many domain boundaries and large domain structures in the body. Its structure would cause large local strain band nucleation with intermittence. However, the trained one is an ideal single-crystalline state with a transformation preferential orientation of variants after almost all domain boundary and large domain structures vanish during thermo-mechanical training. As a result, macroscopic homogeneous deformation occurs on the trained sample surface during deformation. 相似文献
72.
The dual-microphone voice activity detection (VAD) technique is proposed by applying discriminative weight training to achieve optimal weighting of spatial features available within the dual-microphone VAD. Since the motivation behind our method is to use the relevant spatial information available from the two microphones, we employ the phase difference, coherence, and power level difference ratio (PLDR) as a feature vector, and then use this feature vector to derive the maximum a posteriori (MAP) probabilities. Then, we combine each MAP probability based on a discriminative weight training, i.e., the minimum classification error (MCE) method to offer an optimal VAD decision in a spectral domain, which successfully represents the dynamic evolution of speech over time even in the non-stationary noise environments. The proposed dual-microphone VAD algorithm outperforms conventional dual-microphone VAD methods based on only single feature among the PLDR, phase difference, and spectral coherence. 相似文献
73.
数字化信息系统实验室( Digital Information System Laboratory)(简称DISLab)的引入可以简化物理实验的操作、加快数据采集与处理的速度并提高精度,因此,将DISLab用于课堂演示和微课制作,可以使抽象的理论更加形象化、实验过程动态化,更易于学生对知识的理解和接受。本文以向心力研究实验为例,说明了通过DISLab实验的微课的设计和录制,可以训练物理师范生从学生视角出发,设计教学内容和教学思想、引导学生跟随实验过程进行思考,提高物理师范生的教学技能。 相似文献
74.
本文介绍了作者在工科力学教学中进行的三层次训练与考核,并阐述了它们在训练及培养学生探索未知的能力方面的重要作用。 相似文献
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高职院校实践教学平台的形式多样,校内生产性实训基地是其中之一。化学工程学院纯净水生产车间是陕西国防工业职业技术学院综合考虑化工专业的特殊性进行设计建设的。介绍了车间的设计与建设,描述了车间的运行及教学模式,认为车间的投入运行大大提高了学生的综合实践能力。 相似文献
78.
This study investigates the academic and clinical preparation a speech-language pathologist receives in the area of voice. The purpose is to determine how to structure continuing education and specialty training in vocology, defined as the science and practice of voice habilitation. Surveys were sent to the graduate programs in speech-language pathology accredited by the American Speech-Language-Hearing Association (ASHA) in 1994, and again in 1999. Results from the 1994 survey indicated that students received limited information and clinical experience in handling typical voice cases. Although most programs required a voice disorders course, fewer mandated coursework in normal voice production or clinical experience with voice patients. The follow-up survey showed that the educational environment in 1999 is similar to that in 1994. It is evident that the programs are in compliance with the Educational Training Board model developed by ASHA for basic clinical competence, but no structure for specialty training has yet emerged. 相似文献
79.
“知行统一” 的观念在教育界已深入人心,但是要做到切实履行却非易事。经过为期九年的精心打造,上海交通大学开设的创新型实践课程“结构模型设计与制作” 初步实现了“学与行” 的有机融合,教学效果显著,深受学生欢迎。本文是对该课程的总结与反思,希望对我国相关工科教学改革起到有益的借鉴作用。 相似文献
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