background and aims: since using city power for welding process is not allowed, diesel generators are used as a power supply in construction industries. they could be introduced as a main source of noise pollution. the purposes of this study were to assess and control noise pollution produced by construction diesel generators in hamadan, iran. methods: in this descriptive, cross-sectional study...

the doubly fed induction generator (dfig) is one of the most popular technologies used in wind power systems. with the growing use of dfigs and increasing power system dependence on them in recent years, protecting of these generators against internal faults is more considered. loss of excitation (loe) event is among the most frequent failures in electric generators. however, loe detection stud...

The human body contains a near-infinite supply of energy in chemical, thermal, and mechanical forms. However, the majority implantable wearable devices are still operated by batteries, whose insufficient capacity large size limit their lifespan increase risk hazardous material leakage. Such can be used to exceed battery power limits devices. Moreover, novel materials fabrication methods create ...

This report describes the development of a hand-powered centrifuge to determine hematocrit values in low-resource settings. A hand-powered centrifuge was constructed by using a salad spinner. Hematocrit values were measured by using the hand-powered device, and results were compared with those of a benchtop centrifuge. The packed cell volume (PCV) measured with the hand-powered device correlate...

Entrance of intermittent renewable power energy sources has brought in benefits mainly associated with emission reduction to help the climate change cause and reduce pollution. However, entrance generation sources, wind solar that are by nature not come without its own challenges. Future grids will see continued elevation instantaneous penetration levels may potentially be as high 100% for some...

The portable generators are the main means of compensating the shortage of national electricity power as in Iraq. However, their noise causes a huge disturbance, uncomforting and loss of concentration of the nearby resident. This problem requires a solution because most shops and residential houses use generators. Covering method is a simple and relatively low cost one for reduction of generato...

This study presents an innovative and simple way to increase the rate of heat transfer in a spiral plate heat exchanger model. Several circular cross-section rods, as continuous vortex generators, have been inserted within the spiral plate heat exchanger in the cross-stream plane. The vortex generators are located at various azimuth angles of α=30◦, 60◦, 90◦, and 120◦ with non-dimensional diame...

Energy harvesters with higher power and direct-current (DC) output are of great significance for the energy supply electronic devices. Here, we demonstrate rotary disk multi-phase freestanding-electret generators (MFEGs) enhanced low ripple via a novel design. This design can enhance by reduction generator capacitance improvement transferable charge density through positively utilizing edge eff...