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221.
Douglas Cenzer André Nies 《Proceedings of the American Mathematical Society》2004,132(1):239-249
Let be the lattice of classes of reals. We show there are exactly two possible isomorphism types of end intervals, . Moreover, finiteness is first order definable in .
222.
Influence of a preceding auditory stimulus on evoked potential of the succeeding stimulus 总被引:4,自引:0,他引:4
WANGMingshi LIUZhongguo ZHUQiang LIUJin WANGLiqun LIUHaiying 《科学通报(英文版)》2004,49(10):1032-1037
In the present study, we investigated the influ.ence of the preceding auditory stimulus on the audi-tory-evoked potential (AEP) of the succeeding stimuli, whenthe human subjects were presented with a pair of auditorystimuli. We found that the evoked potential of the succeedingstimulus was inhibited completely by the preceding stimulus,as the inter-stimulus interval (ISI) was shorter than 150 ms.This influence was dependent on the IS1 of two stimuli, theshorter the ISI the stronger the influence would be. The in-hibitory influence of the preceding stimulus might be causedby the neural refractory effect. 相似文献
223.
This study aimed to verify whether the resonant voice based on Lessac's Y-Buzz can be perceived by listeners as resonant and different from habitual voice and to compare them to determine whether this sound exploration improves the vocal production. Nine newly graduated actors, six men and three women without voice complaints, were the subjects. They received a session of Lessac's Y-Buzz training from the primary investigator. Before training, they were asked to sustain the vowel /i/ at comfortable frequency and habitual loudness. After training, they were requested to sustain the Y-Buzz they had learned at a comfortable frequency and habitual loudness. Three speech-language pathologists (SLP) trained in voice developed an auditory-perceptive analysis. The pre- and posttraining voice samples were randomly spliced together, edited, and presented in pairs to perceptual judges who were asked to identify the most resonant of the pair. The voice samples were also acoustically compared through the Hoarseness Diagram and acoustic measures using the VoxMetria Software (CTS, version 2.0s, Brazil). The Y-Buzz trials were identified as resonant voice in 74% of the comparisons. The acoustic measures showed a statistically significant decrease of irregularity (P = 0.002) and shimmer (P = 0.38). The Hoarseness Diagram demonstrated how the resonant voice moved toward the normality for irregularity and noise components. The results showed that the resonant voice based on the Y-Buzz can be identified as resonant and different from normal voicing in the same subject, and it apparently implies a better vocal production demonstrating a significant decrease of shimmer and irregularity through the Hoarseness Diagram evaluation. 相似文献
224.
中国蝙蝠听觉和回声定位研究进展 总被引:1,自引:0,他引:1
蝙蝠在中国的种类丰富,共有7科31属117种,对其特殊的回声定位功能进行了分析研究.主要从回声定位蝙蝠的捕食策略,声通讯,听觉系统特化;回声定位和蝙蝠行为状态,生态位,体形,性别的关系;以及听觉的神经生理学和神经组织化学方面,对中国蝙蝠听觉和回声定位研究进展做了综述,提出了存在的问题,并对其研究方向进行了展望. 相似文献
225.
226.
一种基于听觉模型的抗噪语音识别特征提取方法 总被引:5,自引:2,他引:5
提出了一种新的语音识别特征提取方法。该方法是建立在听觉模型的基础上,通过计算语音的上升过零率作为频率信息并通过非线性幅度加权相结合来获取语音特征。仿真实现了中小词汇量、孤立词的语音识别,得到了较好的实验结果,证明了此方法具有较强的抗噪声性能。 相似文献
227.
Akio Honda Hiroshi Shibata Jiro Gyoba Kouji Saitou Yukio Iwaya Yôiti Suzuki 《Applied Acoustics》2007,68(8):885-896
Transfer effects of playing an auditory game with a virtual auditory display (VAD) were investigated. Furthermore, we analyzed the effects of playing the VAD game on sound localization performance under subjects’ own head-related transfer functions (HRTFs) and HRTFs fitted from those of 16 other adults. Participants performed sound localization tasks initially and 2 weeks later to show the effects. The VAD game players were of three groups, using own HRTFs, fitted HRTFs, and no playing (control). The VAD game-playing results revealed that: (1) the hit rate of the sound localization task for real sound sources increased approximately 20%; (2) the vertical and horizontal localization error decreased significantly; (3) sound localization performance using fitted HRTFs was similar to performance using own HRTFs. Follow-up tests revealed that transfer effects persisted more than 1 month, suggesting that the effects of playing the VAD game transfer to sound localization performance. 相似文献
228.
JIN XinChun QI XueLian YANG XiaoFei LI BaoMing 《科学通报(英文版)》2007,52(18):2532-2542
It is known that consolidation of fear conditioning requires de novo protein synthesis in the amygdala. However, there is controversy about the role of protein synthesis in post-retrieval extinction of fear memory. The present study investigated the effect of protein synthesis inhibition (PSI) in the baso- lateral nucleus of amygdala (BLA) on post-retrieval extinction of auditory fear memory. Intra-BLA infu- sion of the protein synthesis inhibitor anisomycin ‘0’ h post-retrieval facilitated the extinction, but was ineffective if the memory was not retrieved. Anisomycin had no effect on the extinction when it was infused 6 h post-retrieval. The present results suggest that there exists a protein-synthesis-dependent mechanism in the BLA that retards extinction of auditory fear memory. 相似文献
229.
230.
本文阐述了玉米(Zea mays L.掖单2号)离体根氧化还原活性与缓冲液浓度及洗涤时间之间的相互关系,并测定了呼吸速率和ATP含量的变化。 相似文献