功能过强性发声模式主观评估量表的临床应用研究

目的:探究功能过强性发声模式主观评估量表的临床应用。方法:选取2015年5月至2017年5月进行体检的正常嗓音患者(A组)以及同时期就诊的功能性病理嗓音(B组)、器质性病理嗓音患者(C组)各50例作为研究对象,对患者的嗓音障碍指数(voice handicap index,VHI)、GRBAS、硬起音率和声道紧张度进行评价,对主观评估进行效度和信度分析。结果:功能过强性发声模式的主观评估中,Cronbach’α系数为0.899,S-CVI/Ave指数为0.901,KMO检验值为0.867,Bartlett球形检验值P<0.001,表明该方法具有良好的效度和信度。结论:声道紧张度评分评估功能性过强发声模式具有良好的效度和信度,可在临床推广使用。

声带息肉和声带小结的发声模式比较

目的:本研究把声带小结、声带息肉患者根据有否肌紧张性发声模式(MTP)分为两组,旨在初步探讨两者的发声模式差异。方法:根据动态喉镜的检查结果,把56例声带小结、声带息肉患者分为存在和不存在MTP两组,并对MTP组进行分型,运用统计学方法对两者的发声模式特点进行比较。结果:存在MTP声带小结患者占85%,而存在MTP声带息肉患者仅占55.56%,两者之间的差异有统计学意义(P<0.05);MTP发声模式以MTPⅢ型最常见,MTPⅠ型、MTP型Ⅱ次之,MTPⅣ型较少见。结论:声带小结患者中普遍存在MTP,而声带息肉患者中仅部分存在MTP,提示两者的发声模式并不一致。

西安回坊话单字调的声学及发声分析

以两男两女为例,分析了西安回坊话的单字调,得出以下研究结果:第一,在调值上,西安回坊话单字调,每度之间相差3.3个半音。阴平调是中降调,记为31;阳平调是高升调,记为24;上声调是高降调,记为51;去声调是高平调;记为44。第二,在开商模式方面,西安回坊话的阴平调是降,阳平调是平,上声调是降,去声调是平。第三,在速度商模式方面,西安回坊话的阴平调是降,阳平调是升降,上声调是平,去声调是平。

Strength and damage evolution mechanism of rock mass with holes under cyclic loading

The damage and failure law of rock mass with holes is of great significance to the stability control of roadways. This study investigates the mechanical properties and failure modes of porous rock masses under cyclic loading, elucidates the acoustic emission (AE) characteristics and their spatial evolution, and establishes the interrelation among AE, stress, strain, time, and cumulative damage. The results reveal that the rock mass with holes and the intact rock mass show softening and hardening characteristics after cyclic loading. The plastic strain of the rock mass with holes is smaller than that of the intact rock mass, and the stress −strain curve shows hysteresis characteristics. Under uniaxial compression, the pore-bearing rock mass shows the characteristics of higher ringing count, AE energy, b-value peak, and more cumulative ringing count in the failure stage, while it shows lower characteristics under cyclic action. At the initial stage of loading, compared with the intact rock mass, the pore-containing rock mass shows the characteristics of a low b-value. The AE positioning and cumulative damage percentage are larger, and the AE positioning is denser around the hole. The specimen with holes is mainly shear failure, and the complete specimen is mainly tensile shear failure.

Monitoring Tool Wear States in Turning Based on Wavelet Analysis

To monitor the tool wear states in turning, a new way based on the wavelet transformation to get the signal characters, which can reflect the tool wear states, was proposed. Using discrete dyadic wavelet transform, the acoustic emission(AE) signal of cutting process was decomposed; the root mean square(RMS) values of the decomposed signals at different scales were taken as the feature vector; the technique of fuzzy pattern identification was used to real time monitor the tool wear states. Based on choosing the suitable standard samples, this method can correctly identify the tool wear states. Experiments showed that the technique based on wavelet analysis is suitable for real time implementation in manufacturing application.

Effect of heterogeneity on mechanical and acoustic emission characteristics of rock specimen

The influence of heterogeneity on mechanical and acoustic emission characteristics of rock specimen under uniaxial compress was studied with numerical simulation methods.Weibull distribution function was adopted to describe the mesoscopic heterogeneity of rocks.The failure process of heterogeneous rock specimen under uniaxial loading was simulated using FLAC 3D software.Five schemes were adopted to investigate the influence of heterogeneity.The results demonstrate that as the homogeneity increases,the peak strength and brittleness of rocks increase,and the macro elastic modulus improves as well.Heterogeneity has great influence on macro elastic modulus and strength when the homogeneity coefficient is less than 20.0.The volume expansion is not so obvious when the homogeneity increases.As the homogeneity coefficient increases the acoustic emissions modes change from swarm shock to main shock.When the homogeneity coefficient is high,the cumulative acoustic emission events-axial strain curve is gentle before the rock failure.The numerical results agree with the previously numerical results and earlier experimental measurements.

Failure modes and slabbing mechanisms of hard rock with different height-to-width ratios under uniaxial compression

To determine the relationship between slabbing failure and the specimen height-to-width(H/W)ratio and to analyze the conditions,characteristics,and mechanism of slabbing failure in the laboratory,uniaxial compression tests were conducted using six groups of granite specimens.The entire failure process was recorded using strain gauges and high-speed cameras.The initiation and propagation of fractures in specimens were identified by analyzing the monitoring results of stress,strain,and acoustic emission.The experimental results show that changes in the specimen H/W ratio can transform the macro failure mode.When the H/W ratio is reduced to 0.5,the macro failure mode is dominated by slabbing.Low load-bearing ability is observed in specimens with slabbing failure,and the slabbing fractures are approximately parallel to the loading direction.Moreover,the fracture propagation characteristics and acoustic emission signals of slabbing failure specimens show typical tensile failure characteristics,indicating that slabbing failure is essentially a special tensile failure.

Acoustic emission characterization methods of damage modes identification on carbon fiber twill weave laminate

In order to get a deep understanding of composite failure mechanisms, the new advanced signal processing methodologies are established for the analysis of the large number of acoustic emission (AE) data obtained from the quasi-static tension test of carbon fiber twill weave composite. For this purpose, AE signals have been collected and post-processed for tension test, and are analyzed with three signal processing methods: Empirical Mode Decomposition (EMD), Hilbert-Huang Transform (HHT) and modified energy entropy algorithm. AE signals can be decomposed into a set of Intrinsic Mode Functions (IMF) components, results from this study reveal that the peak frequency of IMF components based on Fast Fourier Transform (FFT) corresponds to different damage mechanisms of composite. HHT of AE signals can clearly express the frequency distribution of IMF component in time-scale in different damage stages, and can calculate accurate instantaneous frequency for damage modes recognition. The energy entropy based on EMD is introduced to act as a new relevant descriptor of composite damage modes in order to improve the characterization and the discrimination of the damage mechanisms.

Noise shapes the distribution pattern of an acoustic predator

Noise, an obvious effect of urbanization, has a negative impact on animal vocalizations and the hunting efficiency of acoustic predators. However, the influence of noise pollution on the spatial distribution of populations remains understudied. The aim was to assess the factors shaping the distribution pattern of an acoustic predator （long-eared owl Asio otus） in an urban-farmland matrix. We hypothesized that the probability of an acoustic predator occurring decreases with growing nocturnal noise emission. This owl survey was conducted in Krak6w （S Poland） on 79 ran- domly selected sample plots （1 km x 1 km）. Six habitat variables （area of parks, woodlands, grass- land, arable land, habitat diversity index, and noise pollution） were identified and correlated with the probability of the species＇ occurrence. Proximity to pedestrian routes and roads, habitat frag- mentation, and noise intensity was also defined at nest sites and random sites. Long-eared owls occurred on 37% of the sample plots. Occupied plots had a greater area of grassland and arable land as well as a lower level of noise pollution than the unoccupied ones. A multivariate model revealed that area of grassland and nocturnal noise emission was significantly correlated with the probability of long-eared owls occurring and that the high probability of occurrence recorded on plots with large areas of grassland was reduced by noise pollution. The noise intensity recorded at nest sites was also significantly lower than at random sites. This study suggests that apart from habitat factors, the distribution of acoustic predators in an urban matrix is driven by noise pollu- tion. This highlights the importance of proper landscape management, that is, maintaining large grassland areas and preventing noise from increasing within them.