Abstract Ventilation duct systems are indispensable for air purification and room temperature management in industrial commercial buildings. The noise generated by blowers ventilating spaces should be as low possible. In addition, to power the wireless nodes monitoring ventilation conditions such pressure at any positions all ducts, electric is preferred situ without batteries wired supply. thi...

Kualitas akustik yang baik menjadi salahsatu syarat untuk Masjid baik. bisa diukur dari tingkat kejelasan ucapan (Clarity), kecukupan kekerasan suara (Sound Pressure Level-SPL) dan gema tidak terlalu panjang mengganggu aslinya. Kondisi kurang bagus dialami oleh Baitul Manshurin YBIBM terletak di Kp. Cijambe, Ds. Cinunuk , Kec. Cileunyi Kab. Bandung. kualitas berdasarkan hasil observasi ruangan ...

the aim of the present study was to assess the industrial noise pollution and its effects on the blood pressure of workers during activities intextile factory in ilam,which is situated in west of iran. a cross-sectional study was performed on a group included 81 workers and 30 people as sample and control group, respectively. a questionnaire was filled out and then the other measurements includ...

The paper presents the preliminary results of experimental investigation four various loudspeakers used for driving synthetic jet actuator. parameters, characteristic velocity, pressure inside cavity, device sound level (SPL), and heat sink thermal resistance, were presented input power frequency. resonance frequency was determined based on electrical impedance. highest momentum velocity achiev...

Heavy-duty diesel engines equipped with turbochargers is an effective way to alleviate energy shortage and reduce gas emissions, but their compressor aerodynamic noise emissions have become important issue that needs be addressed urgently. Therefore, study the emission characteristics of a during full operating range, experimental numerical simulation methods were used analyze emissions. The re...

Objective: This work aims to reduce the acoustic noise level of transcranial magnetic stimulation (TMS) coils. TMS requires high currents (several thousand amperes) be pulsed through coil, which generates a loud impulse whose peak sound pressure (SPL) can exceed 130 dB(Z). poses risk hearing and elicits unwanted neural activation auditory brain circuits. Methods: We propose new double-containme...

Abstract Severe service control valves or better, high-pressure reducing can see inlet pressures in excess of 4000 psi. Such are found industries ranging from gas petroleum wells, to chemical plants and steam-producing power (Goodwin, “Specifying Control Valves for Service Conditions”, INTECH FOCUS, November (2022), p. 20). convert high levels kinetic energy through a process conversion sound-p...

Experiment 1 investigated gap detection for random and low-fluctuation noise (LFN) markers as a function of bandwidth (25-1600 Hz), level [40 or 75 dB sound pressure level (SPL)], and center frequency (500-4000 Hz). Gap thresholds for random noise improved as bandwidth increased from 25 to 1600 Hz, but there were only minor effects related to center frequency and level. For narrow bandwidths, t...

Abstract The large acoustic noise of 80-110 dB during magnetic resonance imaging (MRI) scanning harms patients’ comfort and health. can be reduced by hardware modification or active control, but these methods are expensive, difficult, not very effective. In this study, a sequence optimization method is used to mitigate the problem while maintaining image quality. 4 th order polynomial function ...

OBJECTIVE The aim of this work is to study the hitherto unclear aerodynamic parameters of the pseudo-glottis following total laryngectomy. These parameters include airflow rate, sub-pseudo-glottic pressure (SubPsG), efficiency and resistance, as well as sound pressure level (SPL). PATIENTS AND METHODS Eighteen male patients who have undergone total laryngectomy, with an age range from 54 to 7...