The circular saw blade body modification by elastic material layer effecting circular saws sound pressure level when idling and cutting

Thinner saw blades cannot resist large lateral cutting forces due to their lower stiffness. In this paper we propose a composite reinforcement method to improve the mechanical properties of circular saw blades. We analyze and simulate the stress and strain fields of our proposed reinforced circular saws by Finite element method. Our analytical results contain not only influences of reinforcing parameters but also loading conditions on the lateral stiffness and the natural frequency of composite saw blades. Here the reinforcing parameters include: 1) the reinforcement location on circular saw blades, 2) the volume fraction of the reinforcements, 3) the number of the reinforcements; and loading conditions include: 1) the cutting force, 2) the rotational speed. Our composite reinforcement model and simulation results can contribute to a better design of circular saw blades.

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Vibration and Noise Damping Treatment for an Excavator Cab

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.889-890.455 ◽

2014 ◽

Vol 889-890 ◽

pp. 455-458

Author(s):

Yong Zhen Mi ◽

Yi Qi Zhou ◽

Li Wang

Keyword(s):

Sound Pressure Level ◽

Sound Pressure ◽

Pressure Level ◽

Material Layer ◽

Contribution Analysis ◽

Damping Material ◽

Great Decline ◽

Chlorobutyl Rubber ◽

Acceleration Signals

Acceleration signals at the mounts of an excavator cab are collected and analyzed, on the basis of which causes of peak values in the sound pressure level (SPL) at the drivers right ear (DRE) are discussed. A damping material layer made up of chlorobutyl rubber is arranged to the cabs panels by simulations according to results of panel acoustical contribution analysis, which indicates a great decline of the SPL peak values.

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A Simulation Model for Analysis of Roll Tensioning of Circular Saw Blade

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1018.57 ◽

2014 ◽

Vol 1018 ◽

pp. 57-66 ◽

Cited By ~ 7

Author(s):

Uwe Heisel ◽

Thomas Stehle ◽

Hadi Ghassemi

Keyword(s):

Simulation Model ◽

Dynamic Behavior ◽

Dynamic Properties ◽

Life Time ◽

Noise Emission ◽

Hand Tools ◽

Circular Saw ◽

Circular Saw Blade ◽

Saw Blade ◽

Circular Saws

Circular saw blades are very widespread in wood machining. They are used in different batches and sizes and in large quantities from hand tools to large machining centers. Because of this huge range of applications the circular saws have gained great importance in the industry. The rising request to improve the cutting quality, reduce the noise emission and increase the life time requires improvement measures for the dynamic behavior of the circular saw blade. The roll tensioning of the circular saw blade has been empirically established as an elegant solution to improve the static and dynamic properties of the circular saw blade. However, there are several influencing parameters for this process that have not yet been studied scientifically accurate. A scientific and economical solution for the study of various roll tensioning parameters is a simulation model based on finite elements method (FEM) that analyzes the effects on the dynamic behavior of circular saw blade. In this work, a simulation model for roll tensioning of circular saw blades is presented. With this simulation model, the residual stresses induced by the roll tensioning can be calculated. This is very relevant for the changing of dynamic properties of the circular saw blade, such as the shifting of eigenvalues and reduction of side run out. Furthermore, this simulation model allows the investigation of various roll tensioning parameters. This investigation helps to gain a better understanding of the relationship between roll tensioning and improvement of dynamic behavior of circular saw blades. Furthermore, it helps to find the optimization potential of the roll tensioning process which is one of the most important parts of the production line of circular saw blades.

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Contributions of Voice and Nonverbal Communication to Perceived Masculinity–Femininity for Cisgender and Transgender Communicators

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-19-00387 ◽

2020 ◽

Vol 63 (4) ◽

pp. 931-947

Author(s):

Teresa L. D. Hardy ◽

Carol A. Boliek ◽

Daniel Aalto ◽

Justin Lewicke ◽

Kristopher Wells ◽

...

Keyword(s):

Fundamental Frequency ◽

Sound Pressure Level ◽

Sound Pressure ◽

Vocal Tract ◽

Presentation Mode ◽

Pressure Level ◽

Presentation Modes ◽

Audiovisual Stimuli ◽

Vocal Tract Resonance ◽

Point Light

Purpose The purpose of this study was twofold: (a) to identify a set of communication-based predictors (including both acoustic and gestural variables) of masculinity–femininity ratings and (b) to explore differences in ratings between audio and audiovisual presentation modes for transgender and cisgender communicators. Method The voices and gestures of a group of cisgender men and women ( n = 10 of each) and transgender women ( n = 20) communicators were recorded while they recounted the story of a cartoon using acoustic and motion capture recording systems. A total of 17 acoustic and gestural variables were measured from these recordings. A group of observers ( n = 20) rated each communicator's masculinity–femininity based on 30- to 45-s samples of the cartoon description presented in three modes: audio, visual, and audio visual. Visual and audiovisual stimuli contained point light displays standardized for size. Ratings were made using a direct magnitude estimation scale without modulus. Communication-based predictors of masculinity–femininity ratings were identified using multiple regression, and analysis of variance was used to determine the effect of presentation mode on perceptual ratings. Results Fundamental frequency, average vowel formant, and sound pressure level were identified as significant predictors of masculinity–femininity ratings for these communicators. Communicators were rated significantly more feminine in the audio than the audiovisual mode and unreliably in the visual-only mode. Conclusions Both study purposes were met. Results support continued emphasis on fundamental frequency and vocal tract resonance in voice and communication modification training with transgender individuals and provide evidence for the potential benefit of modifying sound pressure level, especially when a masculine presentation is desired.

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Computers and Electronics in Agriculture The sensor to estimate the sound pressure level in eggs

Qeios ◽

10.32388/7x11uf ◽

2020 ◽

Author(s):

Iran Oliveira Silva

Keyword(s):

Sound Pressure Level ◽

Sound Pressure ◽

Pressure Level

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Case study: Theoretical calculation model and variable condition analysis research on the water-splashing noise for natural draft wet cooling towers

Noise Control Engineering Journal ◽

10.3397/1/376812 ◽

2020 ◽

Vol 68 (2) ◽

pp. 137-145

Author(s):

Yang Zhouo ◽

Ming Gao ◽

Suoying He ◽

Yuetao Shi ◽

Fengzhong Sun

Keyword(s):

Theoretical Model ◽

Sound Pressure Level ◽

Water Droplet ◽

Water Distribution ◽

Sound Pressure ◽

Cooling Tower ◽

Distribution Patterns ◽

Calculation Model ◽

Pressure Level ◽

Cooling Towers

Based on the basic theory of water droplets impact noise, the generation mechanism and calculation model of the water-splashing noise for natural draft wet cooling towers were established in this study, and then by means of the custom software, the water-splashing noise was studied under different water droplet diameters and water-spraying densities as well as partition water distribution patterns conditions. Comparedwith the water-splashing noise of the field test, the average difference of the theoretical and the measured value is 0.82 dB, which validates the accuracy of the established theoretical model. The results based on theoretical model showed that, when the water droplet diameters are smaller in cooling tower, the attenuation of total sound pressure level of the water-splashing noise is greater. From 0 m to 8 m away from the cooling tower, the sound pressure level of the watersplashing noise of 3 mm and 6 mm water droplets decreases by 8.20 dB and 4.36 dB, respectively. Additionally, when the water-spraying density becomes twice of the designed value, the sound pressure level of water-splashing noise all increases by 3.01 dB for the cooling towers of 300 MW, 600 MW and 1000 MW units. Finally, under the partition water distribution patterns, the change of the sound pressure level is small. For the R s/2 and Rs/3 partition radius (Rs is the radius of water-spraying area), when the water-spraying density ratio between the outer and inner zone increases from 1 to 3, the sound pressure level of water-splashing noise increases by 0.7 dB and 0.3 dB, respectively.

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