Systems, tools and techniques for measuring downhole parameters are provided. The techniques involve providing a downhole tool with a sensing apparatus. The sensing apparatus has at least one source positionable about the downhole tool, at least one sensor electrode positionable about a front face of the downhole tool for measuring electrical signals from the source, and a raised insulating cover positionable along the front face of the downhole tool for defining at least one contact surface. The raised insulating cover extends over at least a portion of the sensor electrode whereby the sensor electrode is positionable adjacent to the subterranean formation for electrically coupling thereto without direct contact therewith.

Systems, tools and techniques for measuring downhole parameters are provided. The techniques involve providing a downhole tool with a sensing apparatus. The sensing apparatus has at least one source positionable about the downhole tool, at least one sensor electrode positionable about a front face of the downhole tool for measuring electrical signals from the source, and a raised insulating cover positionable along the front face of the downhole tool for defining at least one contact surface. The raised insulating cover extends over at least a portion of the sensor electrode whereby the sensor electrode is positionable adjacent to the subterranean formation for electrically coupling thereto without direct contact therewith.

A data communications system and associated method of data transmission for transmitting data over a three phase power system between a surface and a sub-surface location for an arrangement such as an oil field electrical submersible pump, on each of the three conductors of a three phase cabled connection with an isolation mechanism operable to isolate any given conductor when a fault associated with that conductor is detected. With the system providing a separate AC signal and data transfer on each conductor isolation can be achieved while enabling continued operation.

A method of processing electromagnetic signal data includes: disposing a downhole tool in a borehole in an earth formation, the downhole tool including at least one electromagnetic transmitter; performing a downhole electromagnetic operation, the operation including transmitting an electromagnetic pulse from the transmitter into the formation and measuring a time domain transient electromagnetic (TEM) signal over a selected time interval following a transmitter turn-off time; transforming the measured time domain TEM signal into a frequency domain TEM signal measured; and applying an inversion technique to the transformed frequency domain TEM signal to estimate one or more formation parameters.

A magnetic resonance imaging apparatus according to an embodiment includes a processor and a memory. The memory stores processor-executable instructions that, when executed by the processor, cause the processor to receive an operation of setting an application condition concerning a local excitation pulse that is a radio frequency (RF) pulse for local excitation applied to a local region different from an imaging region; generate a waveform of the local excitation pulse based on the application condition; and set an imaging condition such that an index value calculated from the waveform of the local excitation pulse does not exceed a limit value.

A method for recording a magnetic resonance image data set includes providing a magnetic resonance sequence. The magnetic resonance sequence includes at least one radio-frequency pulse and a slice-selection gradient pulse applied during or before the radio-frequency pulse, which is configured as non-constant. The method includes providing at least one correction term for compensating a magnetic field change of the slice-selection gradient pulse. The magnetic field change is ascertained via a transfer characteristic of the gradient system of the magnetic resonance system. The method also includes recording at least one magnetic resonance image data set with the magnetic resonance sequence using the correction term.

A sensor for the location of metallic objects and also an associated method comprise a plurality of transmitting coils (2.1, 2.2) and at least one receiving coil (1.9) which are arranged such as to be inductively coupled to one another and overlap to a partial extent for the purposes of decoupling the interaction therebetween, whereby there can be obtained a point of optimal cancellation of the interaction. Due to the fact that a flow of current is passed through the transmitting coils (2.1, 2.2) by a sensor electronic system, equal flows of current through the transmitting coils have an effect upon the at least one receiving coil (1.9) which results in a local point of optimal cancellation which moves in a first direction when there is a flow of current in a first transmitting coil (2.1), whereas it moves in another direction when there is a flow of current in a further transmitting coil (2.2), and due to the fact that there is provided a control circuit for the regulation of the currents in the transmitting coils which leads to a displacement of the local point of optimal cancellation which causes cancellation of the received signal, a simple and effective sensor is thereby produced.

A local radio frequency (RF) coil assembly (A) defining a pediatric patient receiving region (12) to be mounted to a patient support table (B) of an MRI scanner (E). The local RF coil assembly (A) includes a rigid coil body (16,18) operatively connected to an adjustable coil part (20) along a hinge axis (26). A carrier (F) is configured to receive a pediatric patient (C) and be positioned into engagement with the local RF coil assembly (A). An interlock assembly (51) holds the adjustable coil part (20) in a selected position (50) when the carrier (F) interacts with the adjustable coil part (20). At least one bearing (34, 36) is configured to pivot and bias the adjustable coil part (20) relative to the carrier (F) and gravity bias the interlock assembly and the carrier (F) into an interlocking engagement. The adjustable coil part (20) is gravity biased to the open position (28) when the carrier (F) is removed.

In a method to determine a complete parameter of a pulse sequence composed of multiple pulse sequence modules for operating a magnetic resonance examination apparatus parameter information of the pulse sequence modules is stored in a memory in leaves and nodes of a tree structure, and the parameter information stored in the tree structure is evaluated to determine the complete parameter of the pulse sequence.

In an image creating device, an obtainer obtains the phase of a magnetic resonance signal generated from a target object upon application of a static magnetic field and a high-frequency magnetic field to the target object (step S102). A calculator calculates a change level of the obtained phase per a predetermined distance in a direction of the static magnetic field (step S103). A generator generates an image representing a positional distribution of a parameter depending on the calculated change level (step S106).