The purpose of this study is to establish a control method to make borehole trajectory smoother. Considering that the complexity of rotary steerable drilling trajectory control and uncertainty of underground work, analysis of the deficiencies for the traditional trajectory control and the rotary steerable drilling trajectory deviation vector control theory, introduced the concept of "trend Angl...

Abstract: Permanent magnetic linear motors(PMLMs) are easier to accelerate and achieve higher precision than rotary motors. Hence, they have a broad range of applications in the manufacturing industry and other motion control fields. Owing to the structural variation, however, the models of permanent magnet linear motors and rotary motors are different. As a result, their motion control systems...

Atom implantation in graphene or graphene nanoribbons offers a rich opportunity to tune the material structure and functional properties. In this study, zigzag graphene nanoribbons with Ti or Sn adatoms stabilised on a double carbon vacancy site are theoretically studied to investigate their sensitivity to sulfur-containing gases (H2S and SO2). Due to the abundance of oxygen in the atmosphere, ...

Abstract Introduction: The aim of this study was to evaluate the efficacy of two rotary instrument systems (ProTaper and Revo-s File) in removing calcium hydroxide residues from root canal walls Materials and Methods:Thirty human  maxillary incisors were instrumented with the ProTaper System up to the F2 instrument, irrigated with 2.5% NaOCl,and filled with a calcium hydroxide intracanal dr...

introduction: retreatment is performed in teeth with unsuccessful root canal therapy or persistent apical lesion. the most important factor for achieving successful retreatment is thorough cleaning and reshaping. niti files and rotary instruments are widely used for the removal of obturatants. this study compared the ability of mtwo and d-race retreatment systems to remove residual gutta-percha...

Aim The Self-Adjusting File (SAF) system has been recommended for use in permanent teeth since it offers more conservative and effective root-canal preparation when compared to traditional rotary systems. However, no study had evaluated the usage of SAF in primary teeth. The aim of this study was to evaluate and compare the use of SAF, K file (manual instrumentation) and Profile (traditional ro...

OBJECTIVES To evaluate modifications in root canal morphology following instrumentation with orifice openers using Computerized Tomography (CT). STUDY DESIGN Experimental in vitro study. A preoperative CT was performed on 49 molars to measure the root canal cross-sections. After preparing the canals with 6 different nickel-titanium (Ni-Ti) rotary system orifice opener type instruments and Gat...