Results 61 to 70 of about 35,610 (162)
四川大学学报. 自然科学版, 1985 用倒扭摆法测试了18 Ni马氏体时效钢的低频内耗.发现在降温中于165℃附近出现正马氏体相变内耗峯.在升温中于700℃附近出现反马氏体相变内耗峯.内耗峯的高度与T/f(T—温度变化速率,f—振动频率)成线性关系,恒温测量时,相变内耗降为背景值.还观察到相变过程中,切变模量发生软化.我们认为这个内耗是由外加切应力促进或加速接近临界的马氏体胚芽的界面位错滑移所引起.
何思明 +3 more
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Modeling seed germination data to meet biodiversity conservation needs in the Mediterranean
Conservation Biology, EarlyView.Workflow to assess the availability and quality of germination data and assign species' thermal risk in the Mediterranean. (a) Assessment of data availability, including the phylogenetic distribution of the number of records (i.e. available germination data); (b) data quality assessment; and (c) assignment of climate risk categories for species that ...
Diana María Cruz‐Tejada +2 more
wiley +1 more source
Gaoya dianqi, 2010 单相自动重合闸是保证电力系统安全稳定的重要举措,在国内外超高压/特高压电力系统中得到了广泛的应用。笔者分析了相电流突变量选相原理及在高压输电线路单相自动重合闸中的应用。用MATLAB7.0仿真了相电流差突变量选相和相电流突变量选相方法,并结合继电保护模块和单相重合闸模块进行仿真分析。结果表明,应用MATLAB对单相自动重合闸故障选相进行仿真分析可获得很好的效果,对理解单相自动重合闸的原理很有帮助。
胥杰 +5 more
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Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
International Journal of Applied Linguistics, EarlyView.ABSTRACT Artificial intelligence (AI) tools now permeate English academic writing. However, evidence on how feedback modalities align with student differences and with psychological mechanisms remains limited. Prior work often reduced learning styles to simple matches with delivery modes and treated learning engagement and writing anxiety as peripheral.
Yi Ren +3 more
wiley +1 more source
四川大学学报. 自然科学版, 2011 在小波变换轮廓术中,采用一维小波变换去解调变形结构条纹包含的物体面形分布时,小波处理所带来的误差分布同被测物体的面形分布及其变化率存在联系.为了减小小波变换轮廓术中相位提取的误差,从小波变换的相关实质出发,提出了利用神经网络的强大学习能力和函数逼近功能来校正相位.该方法以提取相位的一阶和二阶差分、小波尺度因子等相关计算量作为多层前馈型反向传播网络的输入,通过对复杂样本的训练,实现了输入与误差之间的非线性映射.计算机模拟和实验验证了用神经网络校正相位方法的有效性.
蒋模华, 陈文静, 郑志平
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Synthesizing Empirical Research on Learner Metacognition in Second Language Writing
International Journal of Applied Linguistics, EarlyView.ABSTRACT Despite considerable research interest in learner metacognition in second language (L2) writing, there is not yet a review that synthesizes the existing empirical findings and discusses their implications. To fill the void, this systematic review synthesized 39 empirical studies on learner metacognition in L2 writing and examined their salient
Chen Li, Icy Lee, Zhicheng Mao
wiley +1 more source
Ba6Ti2Nb8O30和Sr6Ti2Nb8O30陶瓷的驰豫铁电性能
四川大学学报. 自然科学版, 2005 作者用固相烧结方法合成了具有充满型钨青铜结构的Ba6Ti2Nb8O30和Sr6Ti2Nb8O30陶瓷.不同频率下Ba6Ti2Nb8O30和Sr6Ti2Nb8O30陶瓷介电常数随温度的变化的规律表明,这两种陶瓷的铁电-顺电相变具有明显的驰豫铁电相变特征,相变弥散指数分别为1.95与1.41.它们在1MHz时的居里温度分别为155℃和160℃,两者的居里温度十分相近.同时,对其介电性能的电场可调性进行了初步研究.当外加电场为2kV/cm、频率为10kHz时 ...
袁媛, 陈湘明
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International Journal of Applied Linguistics, EarlyView.ABSTRACT Multilingual students in Anglophone universities often operate in survival mode. While translanguaging supports learning, critical gaps remain in understanding how translanguaging pedagogies transform and sustain motivation in English‐dominant contexts.
Melissa Jufenna Slamet, Julie Choi
wiley +1 more source
The Development and Validation of the Chinese Vocabulary Levels Test
International Journal of Applied Linguistics, EarlyView.ABSTRACT In response to the increasing need for effective Chinese vocabulary assessments, this study developed the Chinese Vocabulary Levels Test (CVLT), a test designed for intermediate‐level Chinese as a second or foreign language (CSL/FL) learners, based on the vocabulary lists (levels 4–6) from the Chinese Proficiency Grading Standards for ...
Shiwei Qi, Ailan Fu
wiley +1 more source
Zhongguo shiyan zhenduanxue, 2006 目的筛查与脑胶质瘤发病相关基因的单核苷酸多态性,进一步寻找胶质瘤易感基因。方法收集入院脑胶质瘤病人的血液。应用PCR扩增的方法对肿瘤相关的基因的特定片段进行扩增。利用变性高效液相色谱技术进行筛查。双向DNA直接测序,在GENBANK进行对比找到突变的碱基,并进行分析。结果变性高效液相色谱筛查后表明,在HLA-DMA基因中检测到了已知杂和性突变,并发现新的突变,HLA-DMA4EC杂合性缺失突变。结论变性高效液相色谱技术在筛查基因的SNPs方面显示了其快速、高通量和准确的特点。HLA ...
徐保锋 +4 more
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