Abstract: A valve actuator having an electric drive motor with a motor shaft and having an output shaft linked to the motor shaft to drive movement of a valve, the actuator further having a control system arranged to provide a first closed loop control of the actuator output shaft and including a controller coupled to a first position sensor to sense the position of the actuator output shaft, and to a second position sensor to sense the position of the motor shaft and to enable determination of the speed of the motor shaft, the control system being configured to respond to sensed signals from the first and second sensors and adjust the motor speed/position accordingly.

Abstract: A downhole releasable connector is described for releasably connecting a wireline to a downhole tool. The connector comprises a first portion arranged to be connected to a wireline and a second portion arranged to be connected to a downhole tool. A locking arrangement is arranged to lock the first and second portions together when in a first position and to release the first and second portions from each other when in a second position. A reversible drive mechanism is provided to move the locking arrangement between the first and second portions. As the drive mechanism is reversible, it is able to lock and unlock the locking arrangement and so release and reconnect the first and second portions of the connector so that it can be tested prior to use providing increased confidence in the tool and allowing inspection of critical parts within the release mechanism.

Abstract: A valve actuator having an electric drive motor with a motor shaft and having an output shaft linked to the motor shaft to drive movement of a valve, the actuator further having a control system arranged to provide a first closed loop control of the actuator output shaft and including a controller coupled to a first position sensor to sense the position of the actuator output shaft, and to a second position sensor to sense the position of the motor shaft and to enable determination of the speed of the motor shaft, the control system being configured to respond to sensed signals from the first and second sensors and adjust the motor speed/position accordingly.

Abstract: A facility for accurately computing taxes is described. In various embodiments, the facility receives configuration information, receiving a set of tax-related information, storing the received the tax-related information, and employs the stored tax-related information to calculate taxes for a transaction. In various embodiments, a system calculates taxes. The system comprises an administration component that stores administrative information relating to jurisdictions in which a business operates, a tax data component that stores at least tax rates relating to the jurisdictions in which the business operates, and a tax law library component that stores tax rules associated with the jurisdictions in which the business operates and indicates which of the tax rates to apply for a transaction.

Abstract: A facility for accurately computing taxes is described. In various embodiments, the facility requests transaction information from a universal connector, requests a tax service provider to calculate taxes based on the transaction information, and reports the calculated taxes. In various embodiments, the facility additionally receives business practice change information and requests the tax service provider to calculate taxes based on the business practice change information.