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1.
耳蜗的声感受是通过将大气压的微小波动转换成沿听神经传导的AP而实现的,HC在这-机-电换能过程中起关键作用。近二十年来,HC换能的生物物理特性研究取得许多重要突破,已在诸多方面从根本上改变了人们对听觉机制的传统认识。本文从HC换能模型、IHC与OHC的功能差异以及耳蜗声分析主动机制等三方面对这一领域进行了讨论与展望。  相似文献   

2.
我省现有7周岁以下聋儿30万名,其中大多数为双耳重度或极重度感音神经性聋。由于目前还没有治疗感音神经性耳聋的有效药物,因此,这些聋儿一般选择配戴合适助听器以补偿听力,让聋儿接受语训开口说话。但是其中一部分聋儿因听力损失严重,使助听器助听效果极差。目前,一种代替正常耳蜗转换功能的人工装置──电子耳蜗使这些生活在无声世界的聋儿重新有了康复希望。电子耳蜗又叫人工耳蜗,是一种把声音信号换成电信号的特殊声电能装置,它能绕过损伤的内耳后细胞,直接刺激听觉,将听觉信号送到大脑,为重度或极重度聋的成人或儿童提供…  相似文献   

3.
他们是一群聋人,和我们想避开人群,享受静谧的心态不同,他们渴望着声音,哪怕是吵杂的、琐碎的,他们都乐意接受.人工耳蜗在这种渴求中应运而生. 抽离前缀"人工",对耳蜗的概念,许多人并不了解.耳蜗在内耳中,形似蜗牛.它感受来自外耳和中耳的声信号,将声音转换为相应的电刺激,从而引发听神经冲动传至听觉中枢,并向大脑皮层传导.大脑再把送达的信息加工、整合,就产生了听觉.  相似文献   

4.
提出了一个用于乐器识别的听觉仿生系统.该系统基于人类听觉系统中对声源识别起关键作用的耳蜗基底膜、内毛细胞、耳蜗核等部位的生理学功能设计出听觉仿生系统,并对乐器特征进行了提取,进而建立模拟听皮层功能的自组织特征映射神经网络,对构建的由7种乐器243个独奏乐曲样本组成的乐器数据库进行分类识别,乐器识别正确率在75%以上.  相似文献   

5.
声舒适是评价建筑室内环境的重要部分,听觉诱发电位是声环境舒适度评价的客观生理指标,听觉诱发电位信号的时频能量特征可以用来评价声环境的舒适性.小波包分析可以探究听觉诱发电位信号时频能量分布规律,分析时运用的小波基不同,产生的结果也不同.为了更好地研究听觉诱发电位信号的时频能量分布,比较了5种小波基函数的时域特点和幅频特性.对16名正常成年人进行了脑干听觉诱发电位实验,将所测16组听觉诱发电位的平均值进行小波包时频能量分析.结果表明,dmey小波分析结果在时频分布上可与实际信号的能量信息相匹配,可以减少各个频带信号分解后的失真问题.选择dmey小波对听觉诱发电位信号进行处理,能够更准确地分析听觉诱发电位信号的时频能量分布,为声环境的舒适性研究提供理论依据.  相似文献   

6.
本文综述了健听者和人工耳蜗植入者的外周听觉系统中的音高感知机制,讨论了人工耳蜗音高感知研究的现状,并介绍了改善人工耳蜗音高感知的研究方向和进展.  相似文献   

7.
介绍一种鸟头侧卧位定向仪的制作、使用及耳蜗内注射HRP的方法,应用该装置可侧卧位固定鸟头;在动物耳蜗内注射示踪物质可对听觉的初级传入中枢进行定位等研究。  相似文献   

8.
为分析中耳的声传递特性,采用声场与结构耦合的人耳有限元模型模拟声音在中耳中正向和逆向传递过程,分别获得外耳道声音激励经听骨链传递到耳蜗的中耳正向压力增益,以及耳蜗声音激励经中耳传递到外耳道的逆向压力增益.通过中耳正、逆向压力增益的乘积来分析声音在中耳往返传递的压力增益,评价中耳对耳声发射传递的影响.在1-3kHz范围内,计算结果显示中耳往返压力增益平均值为-18dB.  相似文献   

9.
音乐流派的自动分类是音乐信息检索系统的重要组成部分.将听觉图像引入音乐流派的分类研究中,用听觉图像模型模拟人耳耳蜗结构,基于音乐流派分类研究常用的GTZAN数据库,将一维音频信号转换为二维听觉图像,对音乐听觉图像进行尺度不变特征转换(SIFT)及空间金字塔匹配(SPM),从局部到整体地提取图像的纹理特征,最后采用LibSVM中线性核函数的支持向量机对音乐流派进行分类.实验结果表明,与同样基于人耳耳蜗结构提出的美尔频率倒谱系数(MFCC)流派分类方法相比,基于听觉图像的流派分类正确率提高15%.  相似文献   

10.
立体声和环绕声像的相关分析   总被引:5,自引:0,他引:5  
提出了立体声重发声像的相关理论分析法。通过对双耳听觉互相关函数的计算,得到声重发时双耳声信号的时间差以及听觉互相关系数I,从而对声像位置和声像的明晰度进行分析,得到了同主观评价实验相一致的结果。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

15.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

16.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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