A model for the calculation of the spreading and deposition of drilling mud and cuttings has been developed. The calculations are based on a Lagrangian particle approach, which means that the properties of the discharge are represented by moving particles in the model domain. The initialization of the particles is based on the output from an Eulerian near-field underwater plume model. In additi...

The extraction of hydrocarbons from shale formations using horizontal drilling with high volume hydraulic fracturing (unconventional shale gas and tight oil extraction), while derived from methods that have been used for decades, is a relatively new innovation that was introduced first in the United States and has more recently spread worldwide. Although this has led to the availability of new ...

INTRODUCTION A novel neurostimulation system allows steering current in horizontal directions by combining segmented leads and multiple independent current control. The aim of this study was to evaluate directional DBS effects on parkinsonian motor features and adverse effects of subthalamic neurostimulation. METHODS Seven PD patients implanted with the novel directional DBS system for bilate...

BACKGROUND Anatomic femoral tunnel placement for single-bundle anterior cruciate ligament (ACL) reconstruction is now well accepted. The ideal location for the tibial tunnel has not been studied extensively, although some biomechanical and clinical studies suggest that placement of the tibial tunnel in the anterior part of the ACL tibial attachment site may be desirable. However, the concern fo...

Horizontal wells can significantly improve the gas production and are expected to be an efficient exploitation method for industrialization of natural hydrates (NGHs) in future. However, near-wellbore hydrate is highly prone decomposition during drilling process, owing disturbance aroused by factors such as fluid temperature, pressure, salinity. These issues result engineering accidents bit sti...

Efforts to identify alternative sources of energy have focused on extracting natural gas from vast shale deposits. The Marcellus Shale, located in western New York, Pennsylvania, and Ohio, is estimated to contain enough natural gas to supply the United States for the next 45 years. New drilling technology-horizontal drilling and high-volume hydraulic fracturing of shale (fracking)-has made gas ...

Catadioptric Omni-Directional Stereo Vision (ODSV) technology is the combination of omni-directional imaging and stereo vision, which has wide application potentials on robot vision and large-scale video surveillance [1-4]. Fig.1 gives the framework of ODSV technology, which includes four major parts: the design of omni-directional stereo vision imaging system, unwarping of omni-directional ste...

This article describes the structure and the working principle of the blind hole drilling device, by application in the production practice proves its feasibility. At present, we commonly used electrical discharge machining and welding method to solve the problem. However, these methods have the low processing efficiency, low manufacturing precision and high cost defect. This paper developed an...

For the current coal mine directional drilling MWD equipment and system are independent of each other, resulting in different forms data at bottom hole, forming islands; Based on B/S architecture mode, by comparing measurement while mode format, requirement module comprehensive acquisition is analyzed; background database integrated collection set up to develop development mine. The verificatio...