Wellbore instability is a quite common event during drilling, and causes many problems such as stuck pipe and lost circulation. It is primarily due to the inadequate understanding of the rock properties, pore pressure, and earth stress environment prior to well construction. This study aims to use the existing relevant logs, drilling, and other data from offset wells to construct a precise mech...

Rapid fluctuation with a frequency dependence of 1/f (with α≃ 1−2) is characteristic of radiation from black-hole objects. Its origin remains poorly understood. We examine the three-dimensional magnetohydrodynamical (MHD) simulation data, finding that a magnetized accretion disk exhibits both 1/f fluctuation (with α≃2) and a fractal magnetic structure (with the fractal dimension of D∼1.9). The ...

Inadequate hole cleaning can lead to many problems in horizontal and directional wells. In this work, we tried to investigate the cutting transport phenomenon by an experimental directional drilling simulator, considering the differences between the operational and experimental conditions. The inclination, fluid type (water, foam, viscous, and dense), rotary speed (0 and 110 rpm), nozzle bit si...

We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20 M⊙. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no events that could be identified as gravitational wa...

Recent near-IR (NIR) and X-ray observations of Sagittarius A*’s spectrum have yielded several strong constraints on the transient energization mechanism, justifying a re-examination of the stochastic acceleration model proposed previously for these events. We here demonstrate that the new results are fully consistent with the acceleration of electrons via the transit-time damping process. But m...

The first detection of gravitational waves (GWs) from a binary black hole merger in 2015 was a milestone in modern physics, and just recently awarded with the Nobel Prize. However, despite the unparalleled sensitivity of the LIGO detectors, there still exist challenges in the analysis of the recorded data. We apply CONVWAVE, a dilated, fully convolutional neural net directly on the time series ...

An empirical relation between 'canonical' X-ray states in black hole X-ray binaries and radio emission is presented. In the Low/Hard state a quasi-continuous radio-emitting jet is produced. In the the High/Soft state the jet is not observed. In the Very High state and at major state transitions, which may correspond physically to rapid and/or significant changes in the inner accretion disc radi...

The analysis of foundation vibrations and geotechnical earthquake engineering problems in civil engineering requires characterization of dynamic soil properties using geophysical methods. Dynamic structural analysis of the superstructures also requires knowledge of the dynamic response of the soilstructure, which, in turn relies on dynamics soil properties. Machine vibrations, blasting and seis...

We consider the gravitational magnification of light for binary systems containing two compact objects: white dwarfs, a white dwarf and a neutron star or a white dwarf and a black hole. Light curves of the flares of the white dwarf caused by this effect were built in analytical approximations and by means of numerical calculations. We estimate the probability of the detection of these events in...