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- OPEN ACCESS ARTICLE
- Condition Monitoring of an Industrial Oil Pump Using a Learning Based Technique
- Sound & Vibration, Vol.54, No.4, pp. 257-267, 2020, DOI:10.32604/sv.2020.05055
- Abstract This paper proposes an efficient learning based approach to detect the faults of an industrial oil pump. The proposed method uses the wavelet transform and genetic algorithm (GA) ensemble for an optimal feature extraction procedure. Optimal features, which are dominated through this method, can remarkably represent the mechanical faults in the damaged machine. For the aim of condition monitoring, we considered five common types of malfunctions such as casing distortion, cavitation, looseness, misalignment, and unbalanced mass that occur during the machine operation. The proposed technique can determine optimal wavelet parameters and suitable statistical functions to exploit excellent features via an…
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Downloads:172
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- An Exact Solution for Acoustic Simulation Based Transmission Loss Optimization of Double-Chamber Silencer
- Sound & Vibration, Vol.54, No.4, pp. 215-224, 2020, DOI:10.32604/sv.2020.011516
- Abstract The optimization of the acoustic silencer volume is very important to develop it and to get high-performance, the importance of the silencer was appeared in industrial field to eliminate the noise of the duct by efficient and economical method. The main goal of this research is to optimize the transmission loss (TL) by analytical method of the Double-Chamber Silencer (DCS), the TL has been selected as the main parameter in silencer because it does not based on the source or the termination impedances. First we calculated the power transmission coefficient (PTC) and the TL of an acoustic silencer, then used…
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Downloads:183
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- Cost Optimized Non-Contacting Experimental Modal Analysis Using a Smartphone
- Sound & Vibration, Vol.54, No.4, pp. 225-236, 2020, DOI:10.32604/sv.2020.011513
- Abstract The vibrations behavior analysis is an essential step in the mechanical design process. Several methods such as analytical modelling, numerical analysis and experimental measurements can be used for this purpose. However, the numerical or analytical models should be validated through experimental measurements, usually expensive. This paper introduces an inexpensive smartphone as an accurate, non-intrusive vibrations’ behavior measurement device. An experimental measurement procedure based on the video processing method is presented. This procedure allows the measurement of the natural frequencies and the mode shapes of a vibrating structure, simply by using a smartphone built-in camera. The experimental results are compared to…
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Downloads:1513
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- Frequencies Rotation at High Sound Pressure Levels Toward Low Frequencies
- Sound & Vibration, Vol.54, No.4, pp. 237-246, 2020, DOI:10.32604/sv.2020.011086
- Abstract Today, analyzing of sound pressure level and frequency is considered as an important index in human society. Sound experts believe that analyzing of these parameters can help us to better understanding of work environments. Sound measurements and frequency analysis did to fix the harmful frequency in all sections in Shiraz gas power plant with sound analyzer model BSWA 308. The sound pressure levels (LP) and the one and one-third octave band were continuously measured in A and C weighting networks and slow mode for time response. Excel 2013 and Minitab 18.1 software used for statistical calculations. Results analyzed by Minitab…
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Views:189
Downloads:127
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- Noise Control of a Domestic Refrigerator Using a Natural Material Based Composite
- Sound & Vibration, Vol.54, No.4, pp. 247-256, 2020, DOI:10.32604/sv.2020.011011
- Abstract This paper studies the acoustics of a frost free three door domestic refrigerator. Then, as a case study, the radiated noise reduction in the refrigerator using a natural material base composite is presented. Composites manufactured out of Jute, which is a plant fiber abundantly and cheaply available in India and Bangladesh are used in the noise reduction in the refrigerator. Mostly in this work, composites made out of felts of jute were used as barriers for noise control of the refrigerator. Measured acoustical, thermal and physical properties of various jute composites are reported. Noise sources in the refrigerator were characterized…
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Views:188
Downloads:149
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- Weighing and Prioritizing Noise Control Methods Using the Delphi Technique and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) in an Iranian Tire Manufacturing Factory
- Sound & Vibration, Vol.54, No.3, pp. 201-213, 2020, DOI:10.32604/sv.2020.08651
- Abstract Undoubtedly, noise has become a major hazardous issue in today’s industrial world, with a lot of people suffering from exposure to excessive noise in their work environments. This study was conducted to weigh and prioritize noise control methods in an Iranian tire manufacturing complex in Iran. The Delphi method and the Technique for Order Preference by Similarity and an Ideal Solution (TOPSIS) were utilized for this purpose. This cross-sectional, descriptive study was conducted in the baking hall of an Iranian tire manufacturing factory in 2016. To weigh and prioritize noise control methods, Analytic Hierarchy Process (AHP) and TOPSIS were applied.…
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Views:702
Downloads:392
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- Frequencies of Lock Gate Structure Coupled with Reservoir Fluid
- Sound & Vibration, Vol.54, No.3, pp. 179-200, 2020, DOI:10.32604/sv.2020.010679
- Abstract This study determines the natural frequencies of the lock gate structure, considering the coupled effect of reservoir fluid on one side using the finite element method (FEM). The gate is assumed to be a uniformly thick plate, and its material is isotropic, homogeneous, and elastic. The reservoir fluid is assumed to be inviscid and incompressible in an irrotational flow field. The length of the reservoir domain is truncated using the far boundary condition by adopting the Fourier series expansion theory. Two different assumptions on the free surface, i.e., undisturbed and linearized, are considered in the fluid domain analysis. The computer…
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Views:8909
Downloads:3339
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- Cochlear Synaptopathy Following Noise Exposure in Guinea Pigs: Its Electrophysiological and Histological Assessments
- Sound & Vibration, Vol.54, No.3, pp. 163-177, 2020, DOI:10.32604/sv.2020.09880
- Abstract Exposure to high level of noise, may cause the permanent cochlear synaptic degeneration. In present study, a model of noise induced cochlear synaptopathy was established and the electrophysiological and histological metrics for its assessment was designed. 6 guinea pigs were subjected to a synaptopathic noise (octave band of 4 kHz at 104 dB SPL, for 2-h). The amplitude growth curve of Auditory Brainstem Response (ABR) wave-I and wave-III latency shift in presence of noise were calculated. These indexes were considered in pre-exposure, 1 day post exposure (1DPE), 1 week post exposure (1WPE) and 1 month post exposure (1MPE) to noise.…
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Views:627
Downloads:371
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- Position and Velocity Time Delay for Suppression Vibrations of a Hybrid Rayleigh-Van der Pol-Duffing Oscillator
- Sound & Vibration, Vol.54, No.3, pp. 149-161, 2020, DOI:10.32604/sv.2020.08469
- Abstract In this paper, we used time delay feedback to minimize the vibrations of a hybrid Rayleigh–van der Pol–Duffing oscillator. This system is a one-degree-offreedom containing the cubic and fifth nonlinear terms and an external force. We applied the multiple scales method to get the solution from first approximation. Graphically and numerically, we studied the system before and after adding time delay feedback at the primary resonance case (Ω ≌ ω). We used MATLAB program to simulate the efficacy of different parameters and the time delay on the main system.
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Views:795
Downloads:434
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- Assessment of Effects of Concomitant Exposure to Sound, Heat, and Physical Workload Changes on Physiological Parameters in Five Different Combination Modes, a Controlled Laboratory Study
- Sound & Vibration, Vol.54, No.3, pp. 139-148, 2020, DOI:10.32604/sv.2020.08810
- Abstract Exposure to sound, heat, and increased physical workload can change physiological parameters. This study was conducted to evaluate the effect of concomitant exposure to sound, heat, and physical workload changes on physiological parameters in controlled laboratory conditions. This experimental crosssectional study was conducted in 35 male university students with a mean age of 25.75 years and a mean BMI of 22.69 kg/m2 . Systolic and diastolic blood pressure and heart rate were measured after 15 min rest in the laboratory, 5 and 10 min after starting the experiment, and then after 20 min in controlled laboratory conditions in five combination…
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Views:714
Downloads:378
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