Abstract: An apparatus and methods are provided for a front plate having a diverging central bore for firearm sound suppressors that improves noise and flash characteristics during firing a weapon. The central bore is disposed between a back surface and a front surface of the front plate. An untapered portion of the central bore extends from the back surface to a diverging portion that opens toward the front surface. The diverging portion includes a curvature profile configured to allow for more controlled expansion of high-pressure propellant gases exiting of the suppressor through the central bore. The curvature profile provides an included angle of the central bore that decreases secondary flash events accompanying the expulsion of propellant gases accompanying a fired bullet exiting the suppressor through the central bore. The curvature profile exhibits a cross-sectional area of the central bore that is proportional to a distance along the diverging portion.

Abstract: A drill string for drilling a borehole. The drill string may include a downhole motor operable to rotate the drill string and a centralizer assembly. The centralizer assembly may include an outer housing, a lower sub threadably engaged with the outer housing, and a centralizer. The centralizer may include a single eccentric blade, an internal shoulder positioned between the outer housing and the lower sub, and an alignment profile to align the centralizer in an azimuthal position relative to the drill string. The centralizer may be retainable in the aligned azimuthal position by the alignment profile and the internal shoulder being engaged by the outer housing and the lower sub.

Abstract: A welded assembly includes a first object, a second object, and an interlayer. The interlayer is an ESD coating deposited on the first object, and the second object is welded to the coating. The second object may be a material that has thermally sensitive properties, such as a shape-memory material. The second weld may also be made by ESD. The interlayer may be made of more than one layer. The layer or layers may be deposited of a material chosen for its compatibility with one, the other, or both of the material of the first object and the material of the second object.

Abstract: A system and method for intelligently detecting a duplicate address attack is described. The system and method comprise transferring a first address conflict check message; receiving a first address conflict check response message; performing intelligent Duplicate Address Detection (DAD) to determine if the duplicate address attack is valid; and if the duplicate address attack is valid, then reporting the duplicate address attack to a monitoring server. An intelligent switch that detects the DAD attack blocks further address conflict check response messages from the attacker's MAC address.

Abstract: A stabilizer for use in a wellbore may include a downhole tubular configured to couple to a downhole conveyance in a wellbore, as well as two or more helical blades extending radially outward from the downhole tubular. The two or more helical blades are oriented about the downhole tubular to form respective flow paths between adjacent blades. Further, each blade of the two or more helical blades may include a line-of-sight face and a gauge ramp. The line-of-sight face is formed adjacent a leading inner blade wall of the blade at a lower end of the blade and is angularly offset from the leading inner blade wall. The gauge ramp extends from an outer surface of the downhole tubular toward an outer blade surface of the blade proximate the lower end of the blade.

Abstract: A drilling system can be used to drill a borehole. The drilling system may include a first housing defining a main fluid flow path and a second housing defining a bypass flow path toward an annulus of a wellbore. A flow control choke may be positioned between the first housing and the second housing. The flow control choke may include a rotatable section and a stationary section that is stationary relative to the rotatable section. The stationary section may have a curved interface with the rotatable section for restricting a flow of a drilling fluid through the bypass flow path.

Abstract: A pulsed power drilling (PPD) component includes a functional gradient of material from a first portion to a second portion of the PPD component. The functional gradient of material provides a greater wear resistance of the first portion relative to the second portion and a greater electrical conductivity or resistivity of the second portion relative to the first portion.

Abstract: Systems and methods for cold-spraying coatings on rotors in motor assemblies for improving reliability of motor assembly use downhole in wellbores is provided. For example, a motor assembly can include a stator positioned downhole in a wellbore and rotor coupled to the wellbore. The rotor can include a base material and a first coating deposited onto the base material via cold spraying for reducing damage to the rotor. The first coating may include sprayed particles that have a melting point temperature that is higher than a temperature of a gas used in the cold spraying. In some examples, the rotor may include a second coating deposited onto the first coating via cold spraying, high velocity oxygen fuel coating, or high velocity air fuel. The first coating may have a first hardness that is less than a second hardness of the second coating.

Abstract: An apparatus and methods are provided for a gas regulator valve for adjusting cycle speeds of direct gas impingement operated firearms. The gas regulator valve comprises a gas inlet for receiving expanding gases from a fired cartridge and a gas tube for directing the expanding gases to a bolt carrier comprising a firearm. The gas inlet is disposed at the front of an upper receiver comprising the firearm. The gas tube directs the expanding gases into a carrier key of the bolt carrier. The gas regulator valve includes a plug for controlling gas flow through the gas tube. An actuator disposed on a side of the upper receiver enables operating the plug. The actuator enables a practitioner to adjust the flow of expanding gases without moving the firearm out of a shooting position. The actuator includes a key that may be turned by a rim of an ammunition cartridge.

Abstract: A monitor system with dual audio or multiple audio feature for simultaneously monitoring one or more target subjects is disclosed. The monitor system includes a plurality of camera devices and a base station. The plurality of camera devices is arranged to capture video data and sound data of the one or more target subjects independently and simultaneously. The base station is configured to receive the video data and the sound data from the plurality of camera devices, and present the video data and the sound data uninterruptedly. The base station comprises a display panel partitioned into a plurality of regions for displaying multiple views simultaneously using a split-screen technique. The base station outputs an audio signal by combining the sound data from the plurality of camera devices into a single audio signal.

Abstract: An apparatus and methods are provided for a front plate having a diverging central bore for firearm sound suppressors that improves noise and flash characteristics during firing a weapon. The central bore is disposed between a back surface and a front surface of the front plate. An untapered portion of the central bore extends from the back surface to a diverging portion that opens toward the front surface. The diverging portion includes a curvature profile configured to allow for more controlled expansion of high-pressure propellant gases exiting of the suppressor through the central bore. The curvature profile provides an included angle of the central bore that decreases secondary flash events accompanying the expulsion of propellant gases accompanying a fired bullet exiting the suppressor through the central bore. The curvature profile exhibits a cross-sectional area of the central bore that is proportional to a distance along the diverging portion.

Abstract: A downhole motor or pump assembly that includes a stator and a rotor rotatable within the stator. The stator includes a tubular housing and an overlay deposited by cold spray onto an interior of the housing to form overlay lobes along a first length of the stator. The downhole motor or pump may be used to perform downhole operations.

Abstract: Systems and methods for cold-spraying coatings on rotors in motor assemblies for improving reliability of motor assembly use downhole in wellbores is provided. For example, a motor assembly can include a stator positioned downhole in a wellbore and rotor coupled to the wellbore. The rotor can include a base material and a first coating deposited onto the base material via cold spraying for reducing damage to the rotor. The first coating may include sprayed particles that have a melting point temperature that is higher than a temperature of a gas used in the cold spraying. In some examples, the rotor may include a second coating deposited onto the first coating via cold spraying, high velocity oxygen fuel coating, or high velocity air fuel. The first coating may have a first hardness that is less than a second hardness of the second coating.

Abstract: Certain aspects and features relate to a drilling system usable to drill a borehole. The drilling system may include a first housing defining a main fluid flow path and a second housing defining a bypass flow path toward an annulus of a wellbore. A flow control choke may be positioned between the first housing and the second housing. The flow control choke may include a rotatable section and a stationary section that is stationary relative to the rotatable section. The stationary section may have a curved interface with the rotatable section for restricting a flow of a drilling fluid through the bypass flow path.

Abstract: A welding process involves a fixture for holding a workpiece and a welder, or welding electrode. The fixture imposes ultrasonic vibration on the workpiece. The welder vibrates during vibration, and is operable at a first voltage for welding and a second voltage for peening. The peening may occur while the weldmetal is crystallizing. The welding process may be a process of welding two part as together, or of filling a groove or other feature, or of applying or restoring a surface, or of applying a hard facing or ceramic to a parent metal or object. The weldmetal may be the same, or substantially the same, as the parent metal, or it may be different. The different material may be a ceramic material.

Abstract: A downhole motor or pump assembly that includes a stator and a rotor rotatable within the stator. The stator includes a tubular housing and an overlay deposited by cold spray onto an interior of the housing to form overlay lobes along a first length of the stator. The downhole motor or pump may be used to perform downhole operations.

Abstract: A pulsed power drilling (PPD) component includes a functional gradient of material from a first portion to a second portion of the PPD component. The functional gradient of material provides a greater wear resistance of the first portion relative to the second portion and a greater electrical conductivity or resistivity of the second portion relative to the first portion.

Abstract: An apparatus and methods are provided for a front plate having a diverging central bore for firearm sound suppressors that improves noise and flash characteristics during firing a weapon. The central bore is disposed between a back surface and a front surface of the front plate. An untapered portion of the central bore extends from the back surface to a diverging portion that opens toward the front surface. The diverging portion includes a curvature profile configured to allow for more controlled expansion of high-pressure propellant gases exiting of the suppressor through the central bore. The curvature profile provides an included angle of the central bore that decreases secondary flash events accompanying the expulsion of propellant gases accompanying a fired bullet exiting the suppressor through the central bore. The curvature profile exhibits a cross-sectional area of the central bore that is proportional to a distance along the diverging portion.

Abstract: An apparatus and methods are provided for a suppressor to be coupled with a muzzle end of a barrel of a firearm to reduce muzzle blast and muzzle flash. The suppressor comprises a housing having a proximal end and a distal end. A front portion within the housing comprises a series of cylindrical gas expansion chambers for attenuating the temperature and energy of propellant gases accompanying a projectile fired from the firearm. An annular gas expansion chamber surrounds the cylindrical gas expansion chambers and directs a portion of the propellant gases from a rear portion of the suppressor to peripheral vents disposed at the distal end. Lateral chambers within the rear portion deflect and rebound a portion of the propellant gases before passing them into the annular gas expansion chamber. Ledges within the annular gas expansion chamber direct the propellant gases distally through suppressor toward the peripheral vents.

Abstract: A drill string for drilling a borehole. The drill string may include a downhole motor operable to rotate the drill string and a centralizer assembly. The centralizer assembly may include an outer housing, a lower sub threadably engaged with the outer housing, and a centralizer. The centralizer may include a single eccentric blade, an internal shoulder positioned between the outer housing and the lower sub, and an alignment profile to align the centralizer in an azimuthal position relative to the drill string. The centralizer may be retainable in the aligned azimuthal position by the alignment profile and the internal shoulder being engaged by the outer housing and the lower sub.