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71.
Fundamental frequency for 10 male-to-female transsexuals at longterm follow-up (FUP0) was compared to fundamental frequency at initial consultation (IF0) and at discharge from treatment (DF0). Fundamental frequency (F0) values for the three occasions were significantly different [F(2,18) = 24.79, P < .0001] Group mean fundamental frequencies were 125.5 Hz at initial consultation, 168.1 Hz at discharge, and 146.5 Hz at follow-up. There was a moderate but nonsignificant correlation [r(8) = 0.474, P > .05 ns] between the number of intervention sessions and mean F0 achieved by subjects at discharge (DF0). There was a significant correlation between the number of treatment sessions and the maintenance of F0 increases [r(8) = 0.745, P < .05], although the size of the correlation was more modest (r = 0.476) when the data from one subject who had received 90 treatment sessions were removed. 相似文献
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ZhangLinghua ZhengBaoyu YangZhen 《电子科学学刊(英文版)》2005,22(4):437-442
This letter proposes an effective and robust speech feature extraction method based on statistical analysis of Pitch Prequency Distributions (PFD) for speaker identification. Compared with the conventional cepstrum, PFD is relatively insensitive to Additive White Gaussian Noise (AWGN), but it does not show good performance for speaker identification, even if under clean environments. To compensate this shortcoming, PFD and conventional cepstrum are combined to make the ultimate decision, instead of simply taking one kind of features into account.Experimental results indicate that the hybrid approach can give outstanding improvement for text-independent speaker identification under noisy environments corrupted by AWGN. 相似文献
73.
Bacterial flagellar filaments can undergo a polymorphic phase transition in both vitro and vivo environments. Each bacterial flagellar filament has 12 different helical forms which are macroscopically represented by different pitch lengths and helix radii. For external mechanical force induced filament phase transitions, there is so far only one experiment performed by Hotani in 1982, who showed a very beautiful cyclic phase transition phenomenon in his experiment on isolated flagellar filaments. In the present paper, we give a detailed mechanical analysis on Hotani's experiments. Through theoretical computations, we obtained a phase transition rule based on the phase transition mechanism. The theoretical analysis provides a foundation facilitating the establishment of phase transition theory for bacterial flagellar filaments. 相似文献
74.
This study sought to examine the specific relationship between phonation threshold pressure (PTP) and voice fundamental frequency (F(0)) across the pitch range. A published theoretical model of this relationship described a quadratic equation, with PTP increasing exponentially with F(0). Prospective data from eight adults with normal, untrained voices were collected. Subjects produced their quietest phonation at 10 randomly ordered pitches from 5% to 95% of their semitone pitch range at 10% intervals. Analysis included curve fitting for individual and group data, as well as comparisons to the previous model. The group data fit a quadratic function similar to that proposed previously, but the specific quadratic coefficient and constant values differed. Four of the individual subjects' data were best fit by quartic functions, two by quadratic functions, and one by a linear function. This preliminary study indicates that PTP may be minimal at a "comfortable" pitch rather than the lowest pitch tested, and that, for some individuals, PTP may be slightly elevated during the passaggio between modal and falsetto vocal registers. These data support the general form of the theoretical PTP-F(0) function for these speakers, and indicate the possibility of potential refinements to the model. Future studies with larger groups of male and female subjects across a wider age range may eventually reveal the specific nature of the function. 相似文献
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Hai Quan Zhang Wen Ke Liu Li Cheng Zhao Wei Huang Shuai Zhang Ying Li Huai Yang 《中国化学快报》2010,21(2):139-142
<正>A novel series of chiral dopants synthesized from(S)-1,2-propanediol and mesogenic carboxylic acids were characterized by FT-IR,~1H NMR,elemental analysis and their helical twisting properties were investigated by doping the chiral dopants into a nematic liquid crystal host(SLC-1717).The results show that,the helical pitch of N~*-LC mixture exhibited a terminal alkyl chain length dependence and the molecular twisting power β also exhibited a temperature dependence(increasing β with increasing temperature). 相似文献
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紫外-可见光谱测定马尾松纸浆树脂中甘油三酯含量 总被引:5,自引:0,他引:5
用紫外光谱法测定马尾松TMP浆和酸性亚硫酸盐浆正己烷抽出物中甘油三酯的含量,探讨了三油酸甘油酯标准物与纸浆树脂的紫外吸光谱图特征与特征峰位置以及测试时间对吸光度值的影响。结果表明,在实验试剂用量范围内,三油酸甘油酯在412 nm的吸光度与浓度成线性关系,线性相关系数为0.971;吸光度随测试时间呈线性降低关系,相关系数为0.990。再现性实验回收率98%~104%,精确度1.27%~4.03%。利用该方法测定了纸浆与酶处理后纸浆抽提物中甘油三酯的含量,评价了酶处理纸浆降解甘油酯的效果。马尾松TMP与酸性亚硫酸盐浆中甘油三酯含量较高,约占总抽提物的50%。酶处理后TMP浆与酸性亚硫酸盐浆中甘油三酯降解率分别达到46.31%和35.55%。 相似文献