Underground tunnel face bolting and pipe umbrella reinforcement are one of the most challenging tasks in construction whether industrial or not, and infrastructures such as roads or pipelines. It is one of the first sectors of economic activity in the world. Through a variety of soil and rock, a cyclic Conventional Tunneling Method (CTM) remains the best one for projects with highly variable gr...

Electronics are used in modern oil and gas exploration to collect, log, and/or process data such as heading and inclination, weight on the bit, vibration, seismic/acoustic response, temperature, pressure, radiation, and resistivity of the strata. High-temperature electronics are needed that can reliably operate in deep-well conditions (up to 250°C). The U.S. Department of Energy Deep Trek progr...

introduction: excessive temperature rise during drilling of the mandible for dental implant placement might damage adjacent osseous tissues. various factors affect temperature rise, including the geometrical parameters of surgical drills, one of which is the drill bit head angle. the aim of this research was to determine suitable drill bit head angle to induce minimum temperature rise during ma...

This study is designed to consider the two important yet often neglected factors, which are factory recommendation and bit features, in optimum bit selection. Image processing techniques have been used to consider the bit features. A mathematical equation, which is derived from a neural network model, is used for drill bit selection to obtain the bit’s maximum penetration rate that corresponds ...

During the drilling process, sealing performance of roller cone bits is severely challenged by complex downhole environment and frequent vibrations. In this paper, a comprehensive thermal–fluid–solid–dynamic multi-field coupling numerical model new-generation single energizer metal seals (SEMS2) developed. The instantaneous SEMS2 studied under periodic vibration, shock, random vibration. Time-d...

In practice, the near-bit signals are usually accompanied by noises generated drilling tool vibration and high-speed rotary. This study introduces discrete wavelet transform to a well area presents new weal signal extraction algorithm, which can eliminate rotary effectively obtain useful gravity attitude based on through hard threshold method. The effectiveness usefulness of our method verified...

application of quantum-dot is a promising technology for implementing digital systems at nano-scale.  quantum-dot cellular automata (qca) is a system with low power consumption and a potentially high density and regularity. also, qca supports the new devices with nanotechnology architecture. this technique works based on electron interactions inside quantum-dots leading to emergence of quantum ...