in the form of passive seismic methods, broadband seismometers have been used in hydrocarbon exploration. the frequency bandwidth typically studied is in the range of 1–6 hz. the observations on low frequency band of microtremors are used to calculate the spectral ratio of vertical and horizontal components (v/h) and power spectral density (psd). attributes based on the v/h ratio and the psd ha...

Background and Aim: Exposure to impact noise (short-term, high intensity) higher than permitted levels results in injury to the auditory system. Armed forces are one of the occupational groups exposed to these types of noises resulting from gunshots. In this study, relevant articles and research on the adverse effects of impact noise, hearing loss, and tinnitus in armed forces and effective con...

Periodic noises are unwished and spurious signals that create repetitive pattern on images and decreased the visual quality. Firstly, this paper investigates various methods for reducing the effects of the periodic noise in digital images. Then an adaptive optimum notch filter is proposed. In the proposed method, the regions of noise frequencies are determined by analyzing the spectral of noisy...

A novel low noise trans-impedance amplifier is proposed using low cost 0.18 µm CMOS technology. A resistive-capacitive feedback is used to extend the bandwidth of the amplifier. As the structure is inductor less, it is suitable for low cost integrated optical interconnects. In this paper Improved Particle Swarm Optimization have applied to determine optimal trans-resistance and noise of propose...

To study the possible interference of low frequency noise on performance and annoyance, subjects categorised as having a high- or low sensitivity to noise in general and low frequency noise in particular worked with different performance tasks in a noise environment with predominantly low frequency content or flat frequency content (reference noise), both at a level of 40 dBA. The effects were ...

We experimentally demonstrate a low-phase-noise tenfold frequency multiplier based on compact integrated optical comb (OFC) generator. The Indium Phosphide (InP) monolithically OFC is flexible scheme using cascaded modulators. extremely broadly tunable in wavelength and repetition frequency, making it interesting for high-spectral-purity mm-waves applications. generation with 2.6 GHz spacing 19...