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1.
本文给出了黑蝉辅助发声器的动力学特性,揭示了发音肌收缩运动的颤动特性。音盖、鼓盖和褶膜的每个振动周期都由与每个单音节的调幅脉冲列(AMPT_(1-3))相对应的子振动(SGV_(a-b,c))组成。与背部振动相比较,SGV_(a-c)具有调音功能的副频带。连续鸣叫时共鸣腔内的气压变化和两侧气门的气流速度分别约7.94—15.88Pa和0.59—0.84cm~3/s,腹部运动时分别增大约7倍和2.6倍。发音肌收缩到临界发声状态产生颤动,同时激励发声膜和调声板-膜产生AMPT_(1-3)和SGV_(a-c)。  相似文献   
2.
In this paper, the dynamic properties of the main sounder (the sounding muscle (SMc) and the sounding membrane (SM)) and the generating mechanism of amplitude-modulation pulse train (AMPT) are given. The acting process of SMc is a quasi-simple harmonic contraction vibration. The amplitudes of soundless and sounding contracting motion are about 17.2 /μm and 29.4/μm, respectively, and the efficiency of dynamic sounding is about 17%, The unsounded motion of SM is a quasi-simple harmonic vibration, and the amplitude is about 7.81/μm. The sounding motion of SM is a complex vibration, and the amplitude is about 12.66 μm. In each syllable of the song, AMPT_(1,2,3) are separately produced by driving vibrations (V_1,2,3)) of three long ribs in the upper half of SM, and the peaks of V_(1,2,3) lead the first pulse of high amplitude in AMPT_(1,2,3) by 0.156 ms, respectively. The membrane structure in the lower half of SM is mainly to transmit contracting movement of SMc.  相似文献   
3.
The dynamic properties of the assistant sounders in the black cicada are given and the twitching properties of Contraction in the sounding muscle are revealed in this paper.For the operculum, tymbal cover and joint membrane, each of their vibration periods consists of three subgroup vibrations (SGV_(a,b,c)) corresponding to amplitude-modulation pulse trains (AMPT_(1,2,3)) in every syllable of synchro song. In comparison with the vibration at dorsum, the SGV_(a-c) have a subband with the function of regulating the tone. During calling song continuously, the pressure change inside the resonant cavity and the airspeed through the spiracles on both sides are about 7. 94—15.88 Paand 0.59—0.84 cm~3/s respectively, and they increase by about 7 and 2.6 times as the abdomen is moved. When the contraction motion of the sounding muscle comes up to the critical Sounding state, it further produces the twitching process, and drives the sounding membrane and the toning plate-membrane to produce AMPT_(1-3) and SGV_(a  相似文献   
4.
黑蚱蝉(C.atrata Fabricius)的复合脉冲型和单脉冲型叫声(CP-和 SP-叫声)分别具有呼叫声和求爱声特性。 CP-叫声的声脉冲由 3个亚脉冲组成,而 SP-叫声为单一脉冲。两者都以约 5000 Hz的主频率为主音的单音调声,但 CP-叫声的主频率幅值比 SP-叫声平均高 10.5 dB。两者发声运动的神经肌肉活动的波形结构虽相似,但 CP-叫声的发声运动由约50 ms的起动过程逐步发展为平稳期,而 SP-叫声快速起动。 SP-叫声发声运动的神经肌肉活动增强而动作周期变慢,其动作电位的宽度、后电位和 EMG的幅值分别比 CP-叫声平稳期内平均增高 52.8%、 88.8%和 26.3%;而声脉冲的潜伏期和重复周期分别平均减慢 49.5%和 38.5%。  相似文献   
5.
In this paper, the geometric structure and the mechanical characteristics of the sounding membrane (SM) are given, and the acting properties of the sounding movement of sM are revealed.SM is an elastic membrane with a non-linear structure. At contracting point, the elastic pressure and the rebounding force are about 0.146 N and 0.044 N, respectively. In the lower half, the rigidity of the convex-like shell increases obviously, its force constant is about 0.4 N/ram. In the upper half, the middle section of the three long ribs narrows, thickens and stiffens, with a breaking pressure of about 0.12N.The forced sounding movement of SM shows that the movement of SM travels along the membrane in the lower half from the contracting point and drives the three long ribs to buckle in turn and to produce a syllable to be basically the same as free song, that is, it consists of the three amplitude-modulation pulse trains of which the main peak frequency of the carrier wave is about 4.8 kHz. The buckling movement of  相似文献   
6.
北京地区蟪蛄蝉(PlatypleurakaempferiFabricurs)的呼叫声和求爱声具有不同的声学特性和行为功能。呼叫低潮声“Zhi-”声和呼叫高潮声“Zhi-”声分别由不规则和规则调幅脉冲组成,声响效果主要取决于主频率分别为7300±61Hz和5819±38Hz的载频带。雌蝉大范围内的飞行趋声反应主要与呼叫高潮声载波的主频特性有关。求爱低潮声“Ou-”声和求爱高潮声“ZhiOu-”声都是由明显失去调幅特性的脉冲组成,声响效果主要取决于基频分别为522±9Hz和594±12Hz的基频带。小范围内的求爱主要与求爱高潮声基频所表征的脉冲时间参数有关。发声机制主要与发声膜结构相适应的三条长肋的激励方式有关。  相似文献   
7.
本文揭示了鸣鸣蝉鸣声的变频特性,并给出了相应的动力学过程。每个单次叫声的前奏和尾声基本上是以主峰频率约4000Hz的基本音(BS)为主音的单音色声,其高潮声多数由5—8个变音节(VTS)“Wéi ying”组成的音变调声。VTS的变频过程由前混音、BS为主音的“Wéi”、中混音和BS的3—5倍频次音(IS_2)为主音的“Ying”组成。BS的1.5—2倍频次音(IS_1)为低强度伴音。变频过程中发音肌的收缩速率虽无明显变化,约220±25Hz,但颤动特性有明显差异,其准正弦和锯齿形颤动分别激发BS,IS_1和IS_2。腹部伴音的上、下运动速度分别平均约2.5—5cm/s和5cm/s。  相似文献   
8.
黑蝉发声膜的长肋可类比为一端夹紧的梁,激励声的基频为3900—5500Hz,与黑蝉鸣声的主峰频率(MPF)的可能范围基本一致。有盖(Op)、鼓盖(TC)和褶膜(JM)可分别类比为一边固定、二边固定其余自由的均匀方板和四边固定的矩形膜,受激振动的基频(f_(OP)~1=940Hz、f_(TC)~1=1200Hz和f_(JM)~1=810Hz),及其f_(OP)~(3,4.5,5,5.5,6)、f_(TC)~(2,2.5,3,3.5)和f_(JM)~(45,65,66,76,77)分别与Op、TC和JM振动的MPF及其主要高频成分基本相一致,共鸣腔和两侧气门可类比为并联谐振电路和并接于输出端的电阻,谐振频率和品质因素与黑蝉鸣声的MPF和调谐度基本相一致。  相似文献   
9.
本文在鸣鸣蝉变音调鸣声基本特性的研究基础上,进一步分析了其发声的原初机制。鸣鸣蝉的每个单次叫声由前奏、含有若干个变音节“Weiying”的高潮声和尾声组成。每个变音节由以基本音(BS)为主的“Wei”和陪音(UP_2)为主的“Ying”合成,陪音(UP_1)为低强度伴音,BS、UP_1和UP_2由发声肌不同特性的颤动分别激励发声膜的长肋LR_2、LR_3和LR_1振动所产生。LR_1和LR_2,3可分别类比为两端张紧的弦和两端铰链中央加载的梁.类比模型发声振动的声学特性,不仅与LR_1,2,3的结构特性相适应,而且与鸣声的声学特性基本相一致.  相似文献   
10.
斑蝉自然鸣声起鸣声和重复声的前奏及高潮声,分别由若干个分别含3个亚脉冲(SP1-3)的脉冲组成。基本音和载频带的主频率(PFb和PFc)份别为338±20Hz和3617±87Hz。起鸣声的前奏合22个脉冲(P1-22),调幅特性逐渐衰变,SP1的载波振荡失去对称性,并与基波叠加,SP2,3近似为正弦波。同时,鸣声由以PFc为主音逐渐转变为以PFb为主音。起鸣的高潮声、重复声的前奏和高潮声都进一步失去调幅特性,载波振荡主要与SP2的基波叠加,其PFc的幅值都比PFb平均低10dB以上,鸣声都是以基本音的PFb为主音。由发声膜的结构来看,其三条长肋的振动频率可能由质量控制逐渐转变为力阻控制,相应的鸣声由以PFc为主音的起鸣前奏逐渐衰变为PFb为主音的高潮声和重复声。  相似文献   
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