Abstract: A system and method for accepting content in a first form, identifying the type of the content, specifying at least a second form, converting the content form from the first to the second form, and continuing conversion for any forms subsequent to the second form. Variant Production Functions create specification-based variant files and supplemental metadata using data from existing resources. A Variant Production Function provides functionality for parsing an existing resource's data, and generating a complete or partial alternate translated form of that resource. The Variant Production Function includes at least the input of the content of the primary target resource file used as the basis for the new variant. Variant Production Functions may be in Auto Generation Configuration Objects, or used as components within a Translation and Transcription Service.

Abstract: In an exemplary embodiment, a computer-implemented method for implementing a test delivery system is provided. The method includes implementing a plurality of interoperable accommodation and accessibility tools, and providing an interface to the test with the plurality of interoperable accommodation and accessibility tools provided on the interface. The method also includes receiving one or more tool settings for a test-taker specifying one or more permitted tools in the plurality of interoperable accommodation and accessibility tools, and customizing the interface based on the one or more tool settings to allow the test-taker access to the one or more permitted tools during the test. The method further includes allowing the test-taker to activate or deactivate each of the one or more permitted tools.

Abstract: In an exemplary embodiment, a computer-implemented method for implementing a test delivery system is provided. The method includes implementing a plurality of interoperable accommodation and accessibility tools, and providing an interface to the test with the plurality of interoperable accommodation and accessibility tools provided on the interface. The method also includes receiving one or more tool settings for a test-taker specifying one or more permitted tools in the plurality of interoperable accommodation and accessibility tools, and customizing the interface based on the one or more tool settings to allow the test-taker access to the one or more permitted tools during the test. The method further includes allowing the test-taker to activate or deactivate each of the one or more permitted tools.

Abstract: The invention relates to a method and an apparatus for use in surveying boreholes. The method of the invention comprises the following steps: providing an instrument package in a leading end of a drillstring, the instrument package comprising first and second single-axis sensors mounted for rotation with the drillstring about the rotational axis of the drillstring, the first sensor being an accelerometer and the second sensor being a magnetic fluxgate or a rate gyro; rotating the drillstring; deriving from the first sensor the inclination angle of the drillstring at the instrument package; and deriving from the second sensor the azimuth angle of the drillstring at the instrument package.

Abstract: A borehole drilling and survey assembly includes a drill string of magnetic material, a non-magnetic drill collar, and a non-magnetic rotary drilling system including a drill bit. A near-bit survey instrument is located in the rotary drilling system at a fixed distance from the junction of the drill string and the drill collar. A second survey instrument is located in the drill collar at a fixed distance from said junction. The survey instruments measure the local values of the component of the earth's magnetic along the borehole axis, and these values are processed to remove the magnetic effects of the drillstring. The survey instruments optionally also measure gravity vector components to enable borehole heading to be derived.

Abstract: A borehole drilling and survey assembly includes a drill string of magnetic material, a non-magnetic drill collar, and a non-magnetic rotary drilling system including a drill bit. A near-bit survey instrument is located in the rotary drilling system at a fixed distance from the junction of the drill string and the drill collar. A second survey instrument is located in the drill collar at a fixed distance from said junction. The survey instruments measure the local values of the component of the earth's magnetic along the borehole axis, and these values are processed to remove the magnetic effects of the drillstring. The survey instruments optionally also measure gravity vector components to enable borehole heading to be derived.

Abstract: The invention relates to a method and an apparatus for use in surveying boreholes. The method of the invention comprises the following steps: providing an instrument package in a leading end of a drillstring, the instrument package comprising first and second single-axis sensors mounted for rotation with the drillstring about the rotational axis of the drillstring, the first sensor being an accelerometer and the second sensor being a magnetic fluxgate or a rate gyro; rotating the drillstring; deriving from the first sensor the inclination angle of the drillstring at the instrument package; and deriving from the second sensor the azimuth angle of the drillstring at the instrument package.

Abstract: A system for controlling the rotation of a roll stabilizable control unit in a steerable rotary drilling assembly comprises an instrument carrier rotatably mounted on a support connected to the drill string. A first rotatable impeller is mounted for rotation by a flow of drilling fluid over the impeller and is coupled to the instrument carrier so as to transmit a torque to it. Sensors carried by the instrument carrier sense the rotational orientation of the instrument carrier and produce a control signal indicative of its rotational orientation, and the torque applied to the instrument carrier by the impeller is controlled, at least partly in response to said signal, so that the instrument carrier can, for example, be roll stabilized if required. A second rotatable impeller is coupled to the instrument carrier for transmitting to it a second torque, which may also be controlled, in the opposite direction to the torque transmitted by the first impeller.

Abstract: The method of the present invention presents a plurality of option panels to a user, each option panel requiring at least one user input which specifies a system option for a selected data processing system. Thereafter, an installation profile is created utilizing these specified system options, including at least a description of the operating system to be utilized and a description of the data processing system hardware configuration. In one embodiment of the present invention this installation profile is then stored in conjunction with a complex multilevel software application on a portable storage media, such as a tape reel. Thereafter, the installation of the complex multilevel software application may be automatically accomplished by reference to the installation profile which contains those values which represent preset installation options.

Abstract: A system for maintaining a downhole instrumentation package in a roll stabilised orientation with respect to a drill string comprises an instrument carrier which is mounted within a drill collar for rotation about the longitudinal axis of the collar. An impeller is mounted on the instrument carrier so as to rotate the carrier relatively to the drill collar as a result of the flow of drilling fluid along the drill collar during drilling. The torque transmitted to the instrument carrier is controlled, in response to signals from sensors in the carrier which respond to the rotational orientation of the carrier, and input signals indicating the required roll angle of the carrier, so as to rotate the carrier in the opposite direction to the drill collar and at the same speed, so as to maintain the carrier non-rotating in space and hence roll stabilised.

Abstract: Borehole surveying methods and apparatus for surveying the true longitudinal magnetic field within a substantially non-magnetic drill collar. A plurality of longitudinal magnetic field measurements are made to provide a longitudinal-position-dependent series of magnetic field measurements BZ(z) which enable the true magnitude of the terrestial magnetic field BZe in the direction of the longitudinal axis of the borehole to be calculated on the basis that BZ(z)=BZe+E(z), where E(z) is the longitudinal-position-dependent longitudinal magnetic field error induced by the magnetism of the drill string and the bottom-hole assembly. Several different methods of calculation are described, including polar and non-polar magnetic error function models.

Abstract: A method of deriving the true magnitude of the terrestial magnetic field in the direction of the longitudinal axis of a borehole at a region of the borehold occupied by an instrumentation package equipped with magnetic vector measuring means for measuring the lateral magnetic vectors Bx and By and further equipped with gravitational vector measuring means for measuring each of the three gravitational vectors Gx, Gy, and Gz.The method comprises the steps of performing said measurements of the magnetic vectors and the gravitational vectors and from said vector measurements solving the equation:Bze=(Bve.Ge-Bx.Gx-By.Gy)/Gzwhere BVe is the vertical component of the terrestial magnetic field at the location of the borehole, and Ge is the terrestial gravity field. The terrestial gravity field Ge may be derived as the square root of the sum of the individual squares of the individual gravity vectors Gx, Gy and Gz, according to the equation:Ge=(Gx.sup.2 +Gy.sup.2 +Gz.sup.2).sup.1/2.

Abstract: A transmitter comprises an impeller assembly rotatable by a liquid flow, and an electrical generator having a stator and a rotor arranged to be driven by the impeller assembly. The impeller assembly comprises a main impeller portion and a secondary impeller portion angularly displaceable relative to one another about the axis of rotation of the impeller assembly in response to a change in load of the generator so as to vary the pressure drop across the rotating impeller assembly. Thus appropriate variation of the load of the generator may be used to control the impeller assembly in such a manner as to transmit pressure signals within the liquid flow. Such a transmitter is particularly suitable for transmitting measurement data to the surface from a measuring instrument at the end of a drill string within a borehole. Furthermore such a transmitter can be constructed so as to be readily retrievable without requiring withdrawal of the drill string from the borehole.

Abstract: An accelerometer has a moving magnet within a housing. The magnet is mounted within a support member connected to the center of a diaphragm so as to permit movement of the magnet along a measurement axis extending in the axial direction of the support member by deformation of the diaphragm and so as to permit movement of the magnet along two mutually orthogonal measurement axes parallel to the diaphragm by flexing of the diaphragm to allow for pivoting of the support member. Furthermore displacement of the magnet with respect to the three mutually transverse measurement axes in response to an applied force is sensed by a pickoff capacitor, and a respective output signal proportional to the component of the applied force along each of the measurement axes is supplied by associated sensing circuitry. Simultaneously the magnet is restored to its null position by associated force coil pairs.

Abstract: The present invention is directed to an assembly for supporting an electrical circuit board within a tube. The assembly comprises a circuit board, an elongated support spine extending longitudinally along the tube and supporting the circuit board and a shock absorbing device for holding the assembly within the tube. The circuit board is disposed parallel to a support surface of the spine with a gap therebetween and a layer of a vibration absorbing material is disposed in the gap between the circuit board and the spine. The vibration absorbing material preferably is an elastomer. Most preferably, the vibration absorbing material comprises a layer of a thixotropic elastomer together with a layer of a silicon elastomer.

Abstract: An accelerometer has a housing defining a chamber, and a magnetizable fluid 11 within the chamber. A permanent magnet is magnetically suspended within the chamber by the magnetizable fluid with its poles oriented along a displacement axis so as to be displaceable from a null position along the displacement axis by an applied force. At least parts of the outer surface of the permanent magnet in the vicinity of its poles are provided with non-magnetizable end members. A sensing arrangement is provided for detecting displacement of the permanent magnet along the displacement axis and for supplying an electrical signal indicative of the applied force. Such an accelerometer is relatively immune to calibration drift and has high measurement accuracy.

Abstract: A down-hole signal generator for a mud-pulse telemetry system comprises a flow constrictor defining a throttle orifice for the mud passing along a drill string, a throttling member displaceable with respect to the throttle orifice to modulate the mud pressure for the purpose of transmitting measurement data up the drill string, and a turbogenerator. The turbogenerator incorporates an annular impeller surrounding a casing and arranged to be driven by the mud passing along the drill string, and a rotatable magnet assembly disposed in a mud-free environment within the casing.

Abstract: An instrument for monitoring the direction of a borehole comprises an elongate casing having its longitudinal axis coincident, in use, with the axis of the borehole, an outer gimbal pivotally mounted within the casing with its pivot axis coincident with the longitudinal axis of the casing, a gyroscope unit mounted in the outer gimbal, a torque motor and a gravity sensor unit. At the beginning of a run the instrument is positioned at the mouth of the borehole. The rate of rotation about an axis transverse to the outer gimbal axis is then sensed by the gyroscope unit, and the outer gimbal is slewed by the torque motor in dependence on the sensed rate so as to align the transverse axis along an East/West direction. The instrument is then moved along the borehole and the rate of rotation about the outer gimbal axis is continually sensed by the gyroscope unit, the outer gimbal being torqued by the motor in dependence on the sensed rate to stabilize the outer gimbal about its axis.

Abstract: A down-hole signal transmitter includes an annular impeller mounted on a cylindrical casing and arranged to be driven by the mud flow passing along a drill string. Each of the impeller and the casing incorporates two sets of magnets with their poles arranged axially relative to one another such that axial movement of the impeller in one direction will tend to be resisted by a force of magnetic repulsion acting between the first set of casing magnets and the second set of impeller magnets and axial movement of the impeller in the opposite direction will tend to be resisted by a force of magnetic repulsion acting between the second set of casing magnets and the first set of impeller magnets. In this way the axial thrust due to the fluid flow is largely taken up. Furthermore the magnetic coupling between the magnet sets in such as to enable driving torque to be transmitted by the impeller to a rotary drive member on which the casing magnets are mounted.

Abstract: A down-hole signal transmitter includes an annular impeller mounted on a cylindrical casing and arranged to be driven by the mud flow passing along a drill string, and an annular stator fixed to the casing upstream of the impeller. The stator has blades canted in one sense relative to the mud flow direction, whereas the impeller has blades parallel to the mud flow direction. The stator blades thereby cause the mud flow to impact on the impeller blades at such an angle that a small or negligible thrust results at the impeller bearings. It is therefore possible to insure a long service life for the bearings.