Shield is a typical mechanical, electrical, hydraulic integration of equipment. Its faults species are complex and diverse. To prevent because machine failure causes economic losses and casualties by shield, this article will introduces rough set theory to the subway shield machine fault diagnosis, propose a method which is based on rough set theory combined with neural network of Metro shield ...

Abstract As one of the main rock-breaking tools on cutterhead shield machine, disc cutter often fails due to abnormal wear, which in turn affects tunneling efficiency order find and replace failed time, a means effectively detect wear state method diagnose failure are required.In this paper, diagnosis combining measurement ARIMA prediction is proposed, theoretical model change law under three c...

In order to respectively reveal the effects of magnetic shield, materials and normal load on the tribo-magnetization, a series of experiments were carried out on a pin-on-block friction tester with a magnetic shield and a three-axis tunneling magneto resistive-type sensor which has high sensitivity and wide linear range. Results showed that the Earth’s magnetic-field can motivate the generation...

The Chamshir water conveyance tunnel (CWCT) with a length of 7.4 km and boring diameter of 5.3 m is excavated using a refurbished single shield TBM, initially designed to work in hard rock formations. This study focuses on engineering geological issues, which are important for checking the suitability of this machine and proposing required modifications for improving its performance in soft roc...

In male rats continually self-administering nicotine (approximately 1.5 mg free base/kg/day), we found a significant increase of nicotinic acetylcholine receptors (nAChRs) labeled by epibatidine (Epb) in 11 brain areas. A large increase of high-affinity Epb binding sites was apparent in the ventral tegmentum/substantia nigra, nucleus tractus solitarii, nucleus accumbens, thalamus/subthalamus, p...

The objective of this study was to evaluate the influence of bull excretory products on the resumption of postpartum luteal function in primiparous, restricted-suckled cows. Hypotheses tested were that resumption of luteal function or proportions of cows that initiate luteal cycling did not differ among cows exposed to a bull (BE), exposed to excretory products of bulls (EPB), not exposed to a ...

Shield tunneling is widely used in urban subway tunnel construction. Old underground pipelines generally have small leakages that are difficult to find. The water leakage significantly reduces the stability of stratum, posing a threat safety shield Therefore, this study established 2D and 3D calculation models for analyzing law diffusion ground under pressure, influences pipeline range length o...