In rotary-percussion drilling, the impact frequency is a crucial variable that closely linked to operational factors determine efficacy of drilling process, such as rate penetration, bit wear, and rock mass characteristics. Typical identification methods rely on complex simulation models or analysis different sensor signals installed specially adapted setups, which are difficult be implemented ...

OBJECTIVE To evaluate the size of ovarian damage caused by ovarian drilling in polycystic ovary syndrome, the amount of inflicted damage was assessed for the most frequently used ovarian drilling techniques. DESIGN Experimental prospective design. SETTING University clinic. PATIENT(S) Six fresh bovine ovaries per technique. INTERVENTION(S) Carbon dioxide (CO(2)) laser, monopolar electro...

To mine in the underground, method of blasting and blast hole drilling methods are mainly, widely accepted. The done with rotary percussion drill. However, there problems terms difficulty operating mining cost resulting from its failure occurs, thus it is hard for companies to find a way underground efficiently, profitability, safely. From this background, necessary build early detection system...

This paper presents a novel pneumatic Down-The-Hole (DTH) hammer with self-rotation bit used for rock drilling, and the mechanical structure working principle are mainly covered. A unique mechanism ratchet pawl incorporated in DTH is proposed percussion-rotation drilling to break rock. The drill can rotate while pipe stays still because of design reduces friction between borehole. Firstly, rati...

Background: The use of lasers has become increasingly common in the field of medicine and dentistry, and there is a growing need for a deeper understanding of the procedure and its effects on tissue. The aim of this study was to compare the erbium-doped yttrium aluminium garnet (Er:YAG) laser and conventional drilling techniques, by observing the effects on trabecular bone microarchitecture and...

The use of lasers has become increasingly common in the field Background of medicine and dentistry, and there is a growing need for a deeper understanding of the procedure and its effects on tissue. The aim of this study was to compare the erbium-doped yttrium aluminium garnet (Er:YAG) laser and conventional drilling techniques, by observing the effects on trabecular bone microarchitecture and ...