Abstract: A method for offshore dual-drive core drilling with three layers of casings under surge compensation is provided. According to the method, a drilling vessel is located at set latitude and longitude coordinates by a dynamic positioning system; drill pipes are stabilized by a seabed template; torques and drilling pressures can be transmitted during drilling of the casings by means of surge compensation of the casings at a wellhead; during drilling for sampling, the surge compensation can compensate to a certain extent for a change in water depth caused by rising or falling tides, or surge, thereby preventing the casings from colliding with equipment and ensuring the safety of wellhead operation; and the drilling of three layers of casings is achieved by means of dual driver heads to effectively protect a wellbore wall, such that high core-drilling rate and good core-drilling quality are achieved during drilling for sampling.

Abstract: The invention provides a managed pressure drilling system. The system comprises a rotating sealing device and a drill string assembly comprising a plurality of drill pipe members. Each drill pipe member has a first tool joint having a first tool joint outer diameter; a second tool joint having a second tool joint outer diameter; and a tubular body between the first and second tool joints having a tubular body outer diameter. In at least one section of the drill string the first tool joint outer diameter, the second tool joint outer diameter and the tubular body outer diameter are substantially the same. The rotating sealing device is configured to form a fluid seal against at least a part of the at least one section of drill string.

Abstract: A flow splitting device for gas reverse circulation drilling, including: an upper joint for connecting with a double-wall drill pipe; an inner tube which is arranged in the upper joint and defines a first passageway in communication with an inner chamber of the double-wall drill pipe, a second passageway in communication with an annular space in the double-wall drill pipe formed between the inner tube and the upper joint; a lower joint, having an upper end fixedly connected with the upper joint and a lower end for connecting with a drill tool; and a flow guiding member provided between the upper joint and the lower joint. A flexible sealing mechanism is provided outside the upper joint. The flexible sealing mechanism extends radially outward relative to the upper joint and the lower joint to form a sealing contact with a wellbore wall.

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 fluid end assembly of a hydraulic fluid pump includes a housing, a plug member, a lock cover, and at least one retention pin. The housing may include at least one bore. The plug member may be positioned at least partially within the at least one bore. The lock cover may be coupled to the housing and configured to retain the plug member within the at least one bore during operation of the fluid end assembly. The at least one retention pin may extend at least partially through a portion of the lock cover to retain the lock cover in a rotational position that retains the plug member at least partially within the bore.

Abstract: A tool includes an internal assembly configured to be positioned at least partially within a body. The tool also includes a collet configured to be positioned at least partially within the body and axially-adjacent to the internal assembly. The collet includes a plurality of fingers that are circumferentially-offset from one another. At least one of the fingers includes a protrusion that extends radially-outward and is configured to be positioned at least partially within a recess formed in an inner surface of the body to secure the collet in place with respect to the body. The tool also includes a collet pin configured to be positioned at least partially within the body, axially-adjacent to the internal assembly, and at least partially within the collet. The collet pin is configured to contact the internal assembly to secure the internal assembly in place within the body.

Abstract: A downhole tool has a tubular body defining an outer wall. A port is defined in the outer wall and a plug is received in the port. The plug is detachably connected to the outer wall and expellable into an annulus between the tubular body and a wellbore in which the downhole tool is placed upon the application of pressure in an interior of the tubular body.

Abstract: A friction reduction system includes a housing including a central axis and a central passage, a valve disposed in the housing and including a first valve body and a second valve body wherein the first valve body is permitted to rotate relative to the second valve body, and a mandrel coupled to the second valve body and permitted to travel axially relative to the housing, wherein a first net pressure force is applied against the mandrel that corresponds to a drilling fluid pressure of a drilling fluid in response to flowing the drilling fluid through the valve and transitioning the valve from a closed configuration to an open configuration, and wherein a second net pressure force is applied against the mandrel that corresponds to a wellbore fluid pressure in response to flowing the drilling fluid through the valve and transitioning the valve from the open configuration to the closed configuration.

Abstract: A subsea assembly including; a foundation, a support device; and a subsea equipment adapter frame is provided. The foundation, support device and subsea equipment adapter frame are separate modular components that can be installed separately. The foundation may be a suction anchor. A method of installing and uninstalling the subsea assembly is also provided.

Abstract: A method of cleaning production tubing in a producing petroleum well comprising the steps: i) providing collection tool configured for both selectively collecting debris while residing downhole to obtain collected debris as well as selectively releasing collected debris while residing downhole; ii) lowering collection tool to specific location at certain depth into production tubing of the producing petroleum well where there is at least a partial choking of local production flow due to accumulated debris deposited on production tubing; iii) collecting accumulated debris with collection tool to obtain collected debris; iv) pulling collection tool to production zone of production tubing or downstream of production zone where there will be enough production flow during production to ensure lifting capacity for collected debris; and v) releasing collected debris into production zone of production tubing to obtain released debris being lifted by production flow when production is running.

Abstract: A downhole transducer assembly capable of being safely operated at a variety of pressures and depths may include a turbine rotatable by a fluid pressure differential rotationally fixed to a rotor in a generator. To reduce the rotational speed of the turbine and rotor, a pressure regulator may limit a fluid pressure differential by controlling the volumetric flow. One or more nozzles may be configured to automatically regulate a nozzle diameter, and therefore the pressure drop across the nozzle. A surge protector may be connected to the generator.

Abstract: A telemetry tool comprising a tube comprising a side wall comprising an exterior side wall surface spaced a distance apart from an interior side wall surface. The tube comprises first and second flanged end connectors suitable for connecting the tube in a telemetry tool string, the tube comprising a major and minor axial bore. The minor axial bore being enclosed within the side wall. The exterior side wall surface is circular in cross section and the interior side wall surface comprises a substantially kidney shaped cross section forming a convex portion of the side wall. The minor axial bore may be enclosed within the convex portion of the side wall. The tool further comprises inductive couplers disposed within the convex portion of the side wall. Alternatively, the inductive couplers may be disposed within the end connectors. The couplers are connected by a cable running through the minor axial bore.

Abstract: An insert for installation on an inner pipe member of a dual-pipe member assembly. The insert is interposed between an external shoulder formed on the inner pipe member and an internal shoulder formed in an outer pipe member. Shoulder-to-shoulder impacts between pipe members results in wear to the insert, rather than to either pipe member. The insert has the shape of an unclosed loop and is positioned within an endless external groove formed in the inner pipe member.

Abstract: A threaded product is provided having an external thread form on a tubular pin member comprises load and stab flanks on either side of a crest, along with smooth transitions between the crest and flanks. An elliptical root between the flanks aids in reducing stress and forms a dope volume between a non-conforming crest of an internal thread form of a tubular box member. Flanks of the internal thread of the box member contact flanks of the external thread of the pin member to form areas of mating contact on either side of the thread.

Abstract: A sonic-powered method is provided for horizontal directional drilling. The method includes positioning a drilling apparatus at one end of a desired path for a generally horizontal bore to be formed, and attaching a drill bit and a drill rod to a drill head. The method also includes advancing the drill bit and the drill rod into and through the ground along the desired path by advancing the drill head to move along the drill mast. A sonic oscillator of the apparatus applies sonic energy in the form of high frequency vibrations to the drill rod and the drill bit to cause the drill bit to penetrate through an underground formation in front of the drill bit along the desired path. The sonic vibrations help efficiently penetrate through different materials in underground formations. The drilling apparatus can also use sonic vibrations to install drill casings to stabilize the bore.

Abstract: A downhole tool control system for a drill string rotary steerable tool that includes a body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port. A spool in the inner chamber is movable into a plurality of positions to direct and control the timing and duration of the flow of drilling fluid to energize pistons of the rotary steerable tool, and to de-energize the pistons. The spool includes a first passage in fluid communication with a drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port.

Abstract: A method and system for determining a position of a linearly translating member. The method may comprise transmitting an excitation into a linearly translating member through one or more couplers from an acoustic device disposed in an outer housing, recording a reflected excitation from the linearly translating member with the acoustic device, and identifying a position of the linearly translating member with respect to the acoustic device. The system may comprise an outer housing, a linearly translating member disposed within the outer housing, an acoustic device disposed in the outer housing and configured to transmit an excitation at various frequencies and various amplitudes and record returned excitation frequencies and amplitudes and time of travel, and an information handling system in communication with the acoustic device.

Abstract: Drill collars may be constructed using solid-state welding processes. Solid-state welding produces robust drill collars with high fatigue lifespans and permits individual segments of the drill collar to be optimized based on their intended use. A drill collar may be formed of a first segment with a different material, density, modulus of elasticity and/or geometry than an adjacent second segment fused thereto. If a segment of a drill collar is damaged in use, the damaged segment may be removed and replaced, possibly without de-rating the drill collar. Methods of forming the solid-state welds may include friction welding adjacent segments to one another such that features in each segment are circumferentially aligned when the weld is formed. Supplemental energy sources may provide additional heat at the welded surfaces to ensure the segments are effectively fused.

Abstract: A vibration isolating coupler including a first coupler portion, a second coupler portion including an external surface and an internal surface portion, and a vibration isolating portion extending between the first coupler portion and the second coupler portion. The vibration isolating portion including a first solid annular portion and a second solid annular portion. The vibration isolating portion including a plurality of slots extending from the first solid annular portion toward the second solid annular portion forming a plurality of vibration isolating elements. Each of the plurality of vibration isolating elements is disconnected from adjacent ones of the plurality of vibration isolating elements by a corresponding one of the plurality of slots. The plurality of vibration isolating elements enabling torsional rotation of the first coupler portion relative to the second coupler portion.

Abstract: An apparatus for retaining a transmission line within a drill string component is disclosed. In one embodiment, such an apparatus includes a drill string component comprising a bore having an internal diameter. A slot is formed in the internal diameter to receive a transmission line. A first feature within the slot is configured to engage a corresponding second feature on the transmission line and thereby retain an end of the transmission line. A sleeve is inserted into the internal diameter to keep the transmission line within the slot. A corresponding system is also disclosed.

Abstract: An apparatus for retaining a transmission line within a drill string component includes a drill string component comprising a bore having an internal diameter. A slot is formed in the internal diameter to receive a transmission line. A first feature within the slot is configured to engage a corresponding second feature on the transmission line and thereby retain an end of the transmission line. The first feature comprises a first angled surface configured to contact and engage a corresponding second angled surface of the second feature. The first and second angled surfaces are oriented such to keep the transmission line retained within the slot when tension is placed on the transmission line. A corresponding system is also disclosed.

Abstract: Trenchless methods for forming a curved hole channel with a steel sleeve and pipeline lifting are provided, including steps of: (T1) drilling a straight hole channel, and inserting the steel sleeve into the straight hole channel; (T2) inserting a guiding pipe into the steel sleeve, and determining a bending direction of a hole channel to be formed; and (T3) inserting a flexible steel-wire pipe into the guiding pipe, and punching to form the curved hole channel. With applying the creative trenchless method for forming the curved hole channel, a specially-made grouting pipe is accurately inserted to a bottom of a subsiding pipeline section, so that a polymer material is conveniently injected to a bottom of a disease position. Though utilizing an expansion force generated by the polymer material, the subsiding pipeline section is uplifted, so as to realize trenchless repairing.

Abstract: An apparatus for retaining a transmission line within a drill string component includes a drill string component comprising a bore having an internal diameter. A slot is formed in the internal diameter to receive a transmission line. A shoulder within the slot is configured to engage a tension anchor attached to the transmission line. The tension anchor is configured to hold tension in the transmission line. The tension anchor includes a first component that is attached to the transmission line, and a second component that is threaded onto the first component. In certain embodiments, the second component contains a connector configured to enable connection to the transmission line. A corresponding system is also disclosed.

Abstract: A window mill is positionable in a wellbore having an annulus. The window mill includes a mill body having an outer surface, a conduit extending axially through the mill body, and a flow port extending from the conduit through the outer surface. A nozzle shuttle including a nozzle is arranged in the conduit. The nozzle shuttle selectively extending over the flow port. A selectively openable port adapter extends between the flow port and the nozzle shuttle. The selectively openable port adapter is responsive to fluid pressure to fluidically expose the conduit to the annulus through the flow port.

Abstract: A system includes a sensor carrier and an integrated data recorder. The sensor carrier includes an outer sub body and an inner sub body. The inner sub body is coupled to the outer sub body by a support leg. The inner sub body includes a recess formed therein. The sensor carrier includes a flow path defined as the space between the outer sub body, the inner sub body, and the support leg. The integrated data recorder is positioned within the recess of the inner sub body such that the integrated data recorder is substantially at the centerline of the sensor carrier. The integrated data recorder includes a sensor package including one or more drilling dynamics sensors, a processor, a memory module, and an electrical energy source.

Abstract: An adapter is provided which allows an external driving tool to drive a driven tool such as an intraosseous needle assembly, where the external driving tool would otherwise be incompatible with the needle assembly. The adapter includes a driver connector having a bore, where the bore is to receive an external driver of the external driving tool. The adapter further includes a driver attached to the driver connector. A cross-sectional shape of the bore is different than a cross-sectional shape of the attached driver. The attached driver includes resilient legs which assist in securing the adapter to the needle assembly. The resilient legs may include protuberances to secure the adapter.

Abstract: Embodiments and methods relate to pulling and installing a product line along an underground arcuate path beneath an obstacle, including pulling the product line for an extended length (i.e. a length that might otherwise be deemed impracticable) along the underground arcuate path beneath the obstacle. Embodiments also relate to a pulling apparatus for installing a product line using a casing along an underground arcuate path beneath an obstacle, having a casing pull head connected to the casing, a product line pull head assembly connected to the product line, and a pull bracket connected to the product line pull head assembly and to the casing pull head sleeve frame.

Abstract: The invention relates to a working machine and a method for working the ground with the working machine, having a mast, along which, by means of a positioning means, a rotary head is moved vertically, by which a telescopic Kelly rod having at least two Kelly bars is displaced and guided. According to the invention the Kelly bars are locked or unlocked automatically by means of a control, wherein by means of a first detection means a rotation angle of at least one Kelly bar is detected and/or by means of a second detection means a force, torque or pressure change is detected in a hydraulic system. By the control a locking and/or unlocking of the Kelly bars is determined depending on the detected rotation angle and/or the detected change.

Abstract: A “Riser Concept” Method and Apparatus includes the bottom-up construction of vertical risers from underground passes through the soil, using a pipe jacking equipment. The pipe jacking equipment vertically push the riser pipe from underground pass upwards through soil formations to waterbody, air intake, terrain surface or like. The method and mechanism can be applied either in traditionally bored tunnel or in tunnel bored by tunnel boring machine.

Abstract: A radial bearing assembly is provided. The radial bearing assembly includes polycrystalline diamond elements, each having an engagement surface in sliding engagement with an opposing engagement surface. The opposing engagement surface includes a diamond reactive material. The radial bearing assembly may be deployed in a variety of components and applications, including in rotor and stator assemblies. Also provided are methods of use of the radial bearing assembly, as well as methods of designing the radial bearing assembly.

Abstract: A tubular engagement interface for interfacing the coupling of two movably engaged tubulars is disclosed. The tubular engagement interface includes a body. The body includes a body engagement surface. A polycrystalline diamond element is coupled with the body, and includes a diamond engagement surface. The tubular engagement interface may be coupled with an inner wall of a first tubular, such that the body engagement surface, the diamond engagement surface, or combinations thereof are engaged with an opposing engagement surface of an outer wall of a second tubular. Alternatively, the tubular engagement interface may be coupled with the outer wall of the second tubular, such that the body engagement surface, the diamond engagement surface, or combinations thereof are engaged with an opposing engagement surface of the inner wall of the first tubular.

Abstract: A system for use in securing bits against rotation in a motor grader may include a bit, with the bit having a shank. The shank may include a locking portion. The system may include an adapter board including a hole configured to receive the shank of the bit. The system may also include an anti-rotation plate configured to engage the locking portion of the shank of the bit such that the anti-rotation plate constrains the bit against rotation with respect to the adapter board.

Abstract: A tubular engagement interface for interfacing the coupling of two movably engaged tubulars is disclosed. The tubular engagement interface includes a body. The body includes a body engagement surface. A polycrystalline diamond element is coupled with the body, and includes a diamond engagement surface. The tubular engagement interface may be coupled with an inner wall of a first tubular, such that the body engagement surface, the diamond engagement surface, or combinations thereof are engaged with an opposing engagement surface of an outer wall of a second tubular. Alternatively, the tubular engagement interface may be coupled with the outer wall of the second tubular, such that the body engagement surface, the diamond engagement surface, or combinations thereof are engaged with an opposing engagement surface of the inner wall of the first tubular.

Abstract: An integrated drill chuck for installing mine roof bolts includes a single integrated piece, the single integrated piece including a body defining a receiving cavity, where the receiving cavity is configured to receive and secure a bit having a square-shaped end and a bit having a hex-shaped end. A drill for installing mine roof bolts is also disclosed. A method for installing mine roof bolts is also disclosed.

Abstract: The disclosure relates to the field of electric power infrastructure and repurposing existing oil and gas pipeline, or other pipelines which are no longer in use for their original purpose, for installation of conduits and electrical cables/conduits, typically underground, for electric power transmission.

Abstract: The disclosure relates to the field of electric power infrastructure and repurposing existing oil and gas pipeline, or other pipelines which are no longer in use for their original purpose, for installation of conduits and electrical cables/conduits, typically underground, for electric power transmission.

Abstract: An interchangeable die comprises a die head, on which a die feature is formed, and a die shank extending in an axial direction from the die head. The die shank includes a first axial shank section, which is adjacent to the die head, and a second axial shank section, which is arranged on the opposite axial side of the first axial shank section from the die head. The first axial shank section has a first diameter and the second axial shank section has a second diameter smaller than the first diameter. The die shank is introducible into a shank receptacle of a die receiving section of a joining tool. A fastening contour for fastening the interchangeable die to the joining tool is formed on the interchangeable die. The fastening contour is configured such that a plug-and-turn connection is establishable between the interchangeable die and the joining tool.

Abstract: A polycrystalline diamond compact drill bit includes a steel body connector and a matrix crown. The matrix crown is provided with multiple main blades extending axially. A rear end surface of the matrix crown is provided with a connecting block projecting backwardly. A front end surface of the steel body connector is provided with a connecting groove having a shape matching a shape of the connecting block. The connecting block is inserted into the connecting groove to form an interference fit with the connecting groove. The rear end surface and the front end surface are fitted to each other. The periphery of the connecting block is provided with an inner positioning hole. A periphery of the steel body connector is provided with an outer positioning hole penetrating into the connecting groove at a position corresponding to the inner positioning hole.

Abstract: Embodiments and methods relate to pulling and installing a product line along an underground arcuate path beneath an obstacle, including pulling the product line for an extended length (i.e. a length that might otherwise be deemed impracticable) along the underground arcuate path beneath the obstacle. A sealing/locking mechanism is located at one end of an outer pipe and at an end of an inner pipe at a position within the underground arcuate path.

Abstract: A steering column assembly includes a first shaft and a second shaft telescopically engaged with the first shaft. The steering column assembly includes a bore extending through the first shaft to the second shaft. A plug is disposed in and occludes the bore. The plug is resiliently expandable relative to the first shaft.

Abstract: An electric submersible pump system can include a shaft; at least one impeller operatively coupled to the shaft; and a bearing assembly that rotatably supports the shaft, where at least one component of the electric submersible pump includes a volumetric composite material that includes polycrystalline diamond material and at least one metallic material.

Abstract: A coupler includes a main body that has an inner bore. The inner bore has a non-circular profile and a longitudinal axis. The coupler includes a cross aperture disposed in the main body. The cross aperture has an axis that is nonintersecting with the longitudinal axis of the main body. The coupler also includes a sleeve that is positioned around an exterior surface of the main body. The sleeve has at least one drilling fluid flow passage.

Abstract: A processing system 100 includes a heat insulating pipe 12, a temperature measuring device 19, and a control device 20. The heat insulating pipe 12 has an inner pipe and an outer pipe. An airtight space is formed between the inner pipe and the outer pipe. A fluid having a temperature lower than that of an indoor space in which the heat insulating pipe 12 is placed is flown within the inner pipe. The temperature measuring device 19 measures a temperature of a surface of the heat insulating pipe 12. The control device 20 is controls a pressure within the airtight space by controlling an exhaust device 16 configured to exhaust a gas within the airtight space based on the temperature of the surface of the heat insulating pipe 12 and a dew-point temperature calculated from a humidity and the temperature of the indoor space.

Abstract: A method of forming a short-hop communications transceiver includes creating, in a conductive tool body, an annular cavity that is electromagnetically coupled to an external tool surface by a surface gap that encircles the tool body. The method further includes positioning material having high magnetic permeability in the annular cavity. The method further includes coupling electrical leads from an electronics module to opposite sides of the surface gap. The method further includes operating the electronics module to perform short-hop telemetry by driving or sensing a voltage signal across the surface gap.

Abstract: A rock drilling shank adaptor includes an elongate body having an internal flushing bore and an entry hole through the sidewall of the adaptor in fluid communication with the internal bore. The adaptor wall at the region of the entry hole is reinforced such that an internal diameter of the flushing bore at the reinforced region is less than an internal diameter of the bore at a position axially beyond the reinforced region.

Abstract: A bearing (12) for a downhole apparatus (10) comprises a body (42) and an upset portion (44). The upset portion (44) extends radially outwards from the body (42), the body (42) and the upset portion (44) defining a channel (46) for receiving fluid flow for lubricating the bearing (12).

Abstract: An assembly for use in a wellbore can include a drill string having an outer housing and a thrust bearing sleeve positioned within the outer housing of the drill string. The assembly can also include a stationary thrust bearing positioned within the thrust bearing sleeve and coaxially around a mandrel extending through a longitudinal length of the thrust bearing sleeve. The assembly can further include an interlocking component including a first end coupled to the stationary thrust bearing and a second end positioned in a recessed portion of a housing of the drill string for preventing the stationary thrust bearing from rotating about a central axis of the mandrel, and for allowing the stationary thrust bearing to rotate about one or more axes perpendicular to the central axis. The assembly can include a flexible member for opposing a rotational force applied to the stationary thrust bearing by another thrust bearing.

Abstract: Aspects of the disclosure can relate to an apparatus including a first member having a first bearing surface formed from a hard material (e.g., a diamond-based material, such as a polycrystalline diamond material), and a second member coupled to an input shaft to translate (e.g., rotate, slide, etc.) with respect to the first member. The second member has a second bearing surface formed from a hard material, and the second bearing surface is to bear against the first bearing surface. In embodiments of the disclosure, the first and second members can be for devices including, but not necessarily limited to: solenoids, generators and/or motors (e.g., out-runner radial flux generators, axial flux generators, radial flux generators/motors, roller vane motors, etc.), gearboxes, rotary data swivels, digital actuators, filters (e.g., inner rotating filters), valves (e.g., proportional valves), sensors (e.g., pressure differential sensors), and so forth.

Abstract: Various drill bits, drilling systems and related methods are provided. In one embodiment, a drill bit comprises a bit body having a face and a shank, at least one insert having a convex engagement surface coupled with the face and at least one wear insert coupled with the shank. In one particular embodiment, the at least one wear insert may be positioned immediately adjacent a coupling end of the shank. The at least one wear insert may include a superabrasive table which may be bonded with a substrate. The at least one wear insert includes a wear surface defined in the superabrasive table. In one embodiment, the superabrasive table may comprise polycrystalline diamond. Similarly, the inset having a convex engagement surface may include a superabrasive material, such as polycrystalline diamond, bonded with a substrate. Such a drill bit may be used, for example, in a top hammer percussion drilling operation.

Abstract: A downhole tool comprises a 360-degree wear band placed circumferentially around a portion of the largest outer diameter (OD) of the tool. In some embodiments, the wear band comprises fiber, resin, and a hard mineral. In some embodiments, the hard mineral comprises alumina oxide, carbide, poly crystalline diamond, or combinations thereof. In some embodiments, the wear band has a thickness of from about 0.001 inch to about 0.5 inch or wherein the wear band has a width of from about 0.01 inch to about 1.0 inch or wherein the wear band is flush with the largest OD of the tool. In some embodiments, the portion of the largest outer diameter of the tool is a part of a mule shoe, or a gage ring, or a bottom sub. Methods of making such a wear band are also disclosed.