Abstract: Methods and apparatuses for controlling a trajectory of a borehole being drilled into the earth are provided. The apparatus includes a drilling system including a drill tubular, a disintegrating device, and a steering system coupled to the drill tubular configured to steer the drilling system, the drilling system configured to drill the borehole by receiving control outputs from at least one control unit for controlling parameters of the drilling system, the at least one control unit configured to provide the control outputs to the steering system, the at least one control unit being configured to provide a depth-based control output.

Abstract: A multiple solar cell having at least two partial cells, at least being formed from a direct semiconductor, having an upper partial cell facing the light and a lower partial cell facing away from the light, an upper bandgap of the upper partial cell being greater than a lower bandgap of the lower partial cell, and an intermediate layer arranged on the lower partial cell side facing away from the light. An optical element including a lower mirror element is arranged on the intermediate layer side facing away from the light, and has a partial element having structural elements arranged in a lateral direction on the intermediate layer side facing away from the light. The structural elements have a mean spacing less than or equal to 1.3 times a spacing value that results from a ratio of a wavelength of the lower bandgap to a refractive index of the lower partial cell or the lower mirror element has a roughness having a root-mean-square value of less than 50 nm.

Abstract: A method for estimating a probability of a drilling dysfunction or a drilling performance indicator value occurring includes entering drilling-related data having a probability distribution into a mathematical model of a drill string drilling a borehole penetrating the earth and entering drilling parameters into the model for drilling the borehole. The method further includes performing a plurality of drilling simulations using the model, each simulation providing a probability of the drilling dysfunction occurring or a probability of a drilling performance indicator value occurring with associated drilling parameters used in the simulation, selecting a set of drilling parameters that optimizes a drilling objective using the probabilities of the drilling dysfunction occurring or the probabilities of a drilling performance indicator value occurring; and transmitting the selected set of drilling parameters to a signal receiving device.

Abstract: A glazing unit is provided for producing an aesthetically pleasing effect. The glazing unit may include at least one polymer with a first structured surface to which a photonic structure is applied. The surface can reflect a first partial spectrum of incident electromagnetic radiation, and can transmit a second partial spectrum of incident electromagnetic radiation. A reflected proportion corresponds to a higher harmonic and is in a visible spectral range.

Abstract: An embodiment of a method of detecting and correcting for spiraling in a downhole carrier includes: deploying the carrier in a borehole in an earth formation as part of a subterranean operation; acquiring time based data from at least one sensor disposed at the carrier; acquiring time and depth data, the time and depth data correlating time values with depths of the carrier; generating a depth based profile based on the time based data and the time and depth data; generating a frequency profile by transforming the depth based profile into the frequency domain; detecting a spiraling event based on an amplitude of the frequency profile; and taking corrective action based on detecting the spiraling event.

Abstract: A glazing unit is provided for producing an aesthetically pleasing effect, comprising or consisting of at least one pane, said pane having a first structured surface to which a three-dimensional photonic structure is applied and the average refractive index of the photonic structure being higher than approximately 1.6 or higher than approximately 1.8 or higher than approximately 1.95. A method of producing such a glazing unit and the use thereof is also provided.

Abstract: Examples of techniques for model-based parameter and state estimation for directional drilling in a wellbore operation are provided. In one example implementation according to aspects of the present disclosure, a computer-implemented method includes receiving, by a processing device, measurement data from the wellbore operation. The method further includes performing, by the processing device, an online estimation of at least one of a parameter to generate an estimated parameter and a state to generate an estimated state, the online estimation based at least in part on the measurement data. The method further includes generating, by the processing device, a control input to control an aspect in the wellbore operation based at least in part on the at least one of the estimated parameter and the estimated state. The method further includes executing a control action based on the control input to control the aspect of the wellbore operation.

Abstract: Methods and apparatuses for controlling a trajectory of a borehole being drilled into the earth are provided. The apparatus includes a drilling system including a drill tubular, a disintegrating device, and a steering system coupled to the drill tubular configured to steer the drilling system, the drilling system configured to drill the borehole by receiving control outputs from at least one control unit for controlling parameters of the drilling system, the at least one control unit configured to provide the control outputs to the steering system, the at least one control unit being configured to provide a depth-based control output.

Abstract: Methods and apparatuses for controlling a trajectory of a borehole being drilled into the earth are provided. The apparatus includes a drilling system including a drill tubular, a disintegrating device, and a steering system coupled to the drill tubular configured to steer the drilling system, the drilling system configured to drill the borehole by receiving control outputs from at least one control unit for controlling parameters of the drilling system, the at least one control unit configured to provide the control outputs to the steering system, the at least one control unit being configured to provide depth-based control.

Abstract: Methods and systems for controlling drilling operations are provided. The methods and systems include conveying a drilling tool into a bore and operating the drilling tool to drill in a direction, creating, with an azimuthal sensing device, a first signal at a first time and a second signal at a second time, wherein each of the first signal and the second signal are indicative of the direction of the drilling tool, and each of the first signal and the second signal are affected by at least one of an unknown but substantially constant offset error or an unknown but substantially constant scale factor error, comparing the first signal with the second signal, and adjusting the drilling direction based on the comparison of the first signal with the second signal.

Abstract: Apparatus and methods for estimating an azimuth of at least part of a bottomhole assembly (BHA) in a borehole intersecting an earth formation, the BHA comprising magnetic material. Methods include conveying the BHA into the borehole; using a first sensor disposed on the BHA to produce a first measurement of a component of a magnetic field at a first borehole depth; estimating the axial component at the first borehole depth in dependence upon the first measurement; estimating an azimuth of at least a part of the BHA at the first borehole depth using the axial component; and controlling drilling operations with the BHA in dependence upon the azimuth. The magnetic field includes an axial component and a plurality of non-axial components unaligned with the axial component. The magnetic field is affected by the magnetic material and the first measurement is representative of at least one non-axial component of the plurality.

Abstract: A glazing unit is provided for producing an aesthetically pleasing effect, comprising or consisting of at least one pane, said pane having a first structured surface to which a three-dimensional photonic structure is applied and the average refractive index of the photonic structure being higher than approximately 1.6 or higher than approximately 1.8 or higher than approximately 1.95. A method of producing such a glazing unit and the use thereof is also provided.

Abstract: Examples of techniques for model-based parameter and state estimation for directional drilling in a wellbore operation are provided. In one example implementation according to aspects of the present disclosure, a computer-implemented method includes receiving, by a processing device, measurement data from the wellbore operation. The method further includes performing, by the processing device, an online estimation of at least one of a parameter to generate an estimated parameter and a state to generate an estimated state, the online estimation based at least in part on the measurement data. The method further includes generating, by the processing device, a control input to control an aspect in the wellbore operation based at least in part on the at least one of the estimated parameter and the estimated state. The method further includes executing a control action based on the control input to control the aspect of the wellbore operation.

Abstract: Methods and systems for controlling drilling operations are provided. The methods and systems include conveying a drilling tool into a bore and operating the drilling tool to drill in a direction, creating, with an azimuthal sensing device, a first signal at a first time and a second signal at a second time, wherein each of the first signal and the second signal are indicative of the direction of the drilling tool, and each of the first signal and the second signal are affected by at least one of an unknown but substantially constant offset error or an unknown but substantially constant scale factor error, comparing the first signal with the second signal, and adjusting the drilling direction based on the comparison of the first signal with the second signal.

Abstract: Methods may include conveying a BHA comprising magnetic material in the borehole to a first borehole depth; using a magnetic sensor disposed on the BHA to produce a first magnetic measurement of a component of a magnetic field at the first borehole depth, the magnetic field including an axial component of the magnetic field oriented along a longitudinal axis of the BHA and a plurality of non-axial components unaligned with the axial component, wherein the magnetic field is affected by the magnetic material and wherein the first magnetic measurement is representative of at least one non-axial component of the plurality; estimating the axial component at the first borehole depth in dependence upon the first magnetic measurement; estimating an azimuth of the BHA at the first borehole depth using the axial component; and controlling drilling operations with the BHA in in dependence upon the azimuth.

Abstract: An embodiment of a method of detecting and correcting for spiraling in a downhole carrier includes: deploying the carrier in a borehole in an earth formation as part of a subterranean operation; acquiring time based data from at least one sensor disposed at the carrier; acquiring time and depth data, the time and depth data correlating time values with depths of the carrier; generating a depth based profile based on the time based data and the time and depth data; generating a frequency profile by transforming the depth based profile into the frequency domain; detecting a spiraling event based on an amplitude of the frequency profile; and taking corrective action based on detecting the spiraling event.

Abstract: Measurements made by a near-bit magnetic sensor on a bottomhole assembly are used to determine the azimuth of the BHA. The sensor may be uncalibrated. The measurement may include a cross-axial component of the magnetic field. The method may include estimating the axial component of the near-bit magnetic field using the measurement. The method may include using the estimated azimuth of the BHA for controlling a direction of drilling. The method may include estimating the component Hxy. The method may include correcting the estimated axial component using an offset between a gravitational toolface and a magnetic toolface.

Abstract: An embodiment of a method of detecting and correcting for spiraling in a downhole carrier includes: deploying the carrier in a borehole in an earth formation as part of a subterranean operation; acquiring time based data from at least one sensor disposed at the carrier; acquiring time and depth data, the time and depth data correlating time values with depths of the carrier; generating a depth based profile based on the time based data and the time and depth data; generating a frequency profile by transforming the depth based profile into the frequency domain; detecting a spiraling event based on an amplitude of the frequency profile; and taking corrective action based on detecting the spiraling event.

Abstract: Methods and apparatuses for controlling a trajectory of a borehole being drilled into the earth are provided. The apparatus includes a drilling system including a drill tubular, a disintegrating device, and a steering system coupled to the drill tubular configured to steer the drilling system, the drilling system configured to drill the borehole by receiving control outputs from at least one control unit for controlling parameters of the drilling system, the at least one control unit configured to provide the control outputs to the steering system, the at least one control unit being configured to provide depth-based control.

Abstract: An apparatus for drilling a borehole into an earth formation includes: a drill bit configured to be rotated to drill into the formation; a drill tubular coupled to the drill bit and configured to rotate the drill bit; a steering device coupled to the drill string and configured to impart a force on the drill string to control a direction of drilling; and a controller configured to communicate a control signal to the steering device. The control signal includes information for directing actuation of the steering device for steering the drill bit in an intended drilling direction. The controller is further configured to direct the steering device to provide a compensating force on the drill string that prevents or reduces an azimuthal deviation from the intended drilling direction due to drill bit walking.