156results about "Reference comparison" patented technology

System and method providing surveillance of an asset such as a process and / or apparatus by providing training and surveillance procedures that numerically fit a probability density function to an observed residual error signal distribution that is correlative to normal asset operation and then utilizes the fitted probability density function in a dynamic statistical hypothesis test for providing improved asset surveillance.

The present invention relates to current measurement apparatus 100. The current measurement apparatus 100 comprises a measurement arrangement 110, 114 which is configured to be disposed in relation to a load 108 which draws a current signal, the measurement arrangement being operative when so disposed to measure the load drawn current signal. The current measurement apparatus 100 also comprises a signal source 112 which is operative to apply a reference input signal to the measurement arrangement 110, 114 whereby an output signal from the measurement arrangement comprises a load output signal corresponding to the load drawn current signal and a reference output signal corresponding to the reference input signal. The current measurement apparatus 100 further comprises processing apparatus 116 which is operative to receive the output signal and to make a determination in dependence on the reference output signal and the load output signal, the determination being in respect of at least one of the load drawn current signal and electrical power consumed by the load.

The invention relates to a single-chip bridge-type magnetic field sensor which comprises a substrate, reference arms, sensing arms, shielding structures and bonding pads, wherein each reference arm and each sensing arm are respectively provided with at least two rows / lines of reference element strands and sensing element strands, each reference element strand and each sensing element strand are formed by one or multiple identical magneto-resistor sensing elements which are electronically connected, the reference element strands and the sensing element strands are arranged and placed in a staggered mode, each magneto-resistor sensing element is one kind of sensing elements selected from AMR, GMR or TMR, each shielding structure is corresponding arranged on each reference element strand, one sensing element strand is located at the interval position between two shielding structures, and one shielding structure is a long-strip-shaped array which is made of soft magnetic materials permalloy. The single-chip bridge-type magnetic field sensor can be achieved in three bridge structures such as quasi bridge, half bridge and full bridge. The single-chip bridge-type magnetic field sensor has the advantages of being small in size, low in cost, small in offset, high in sensitivity, and good in linearity and temperature stability.

The invention provides a single chip difference free layer push-pull type magnetic field sensor electric bridge and a preparation method thereof. The magnetic field sensor electric bridge comprises a substrate, a staggered soft magnetic flux concentrator array and a GMR spin valve or a TMR magnetic resistor sensor unit array which is placed on the substrate and has an X-direction magnetic sensitive direction. Each soft magnetic flux concentrator comprises edges parallel to the X axis, edges parallel to the Y axis and four corners, and the four corners are sequentially marked as A, B, C and D from the upper left position in the clockwise direction. Magnetic resistor sensor units are placed at the gaps between the soft magnetic flux concentrators. Meanwhile, the magnetic resistor sensor units corresponding to the corners A and the corners C of the soft magnetic flux concentrators and the magnetic resistor sensor units corresponding to the corners B and the corners D are defined as push magnetic resistor sensor units and pull magnetic resistor sensor units respectively. The push magnetic resistor sensor units are electrically connected to form one or more push arms, the pull magnetic sensor units are electrically connected to form one or more pull arms, and the push arms and the pull arms are electrically connected to form a push-pull type sensor bridge. According to the single chip difference free layer push-pull type magnetic field sensor electric bridge and the preparation method therefore, the power consumption is low, the magnetic field sensitivity is high, and a magnetic field in the Y direction can be measured.

The present invention provides an apparatus for measuring electrical impedance comprising: two input electrodes contacted to a subject for measuring impedance; a difference amplifier to which two signals inputted to the two input electrodes are inputted; a device for extracting a common mode component of two signals inputted to the two input electrodes; the third electrode contacted to the subject for measuring impedance; the first multiplier to which the common mode component is inputted; the first filter coupled with the first multiplier; the second multiplier coupled with the first filter; wherein a feedback signal outputted from the second multiplier is inputted to the third electrode.

Methods and apparatuses for detection of a presence of a load. A method may include, for example, applying and subsequently removing a supply voltage across the pair of nodes, comparing an electrical potential at one of the pair of nodes at a time after the supply voltage is removed with a reference value, and generating a signal having a value that depends upon an outcome of the comparison.

One or more embodiments are directed to a resistance bridge measurement circuit configured to perform an internal self-check. The resistance bridge measurement circuit may include two or more internal resistors. In one embodiment, the resistance bridge measurement circuit may be configured to measure a first voltage across one of the resistors and a second voltage across a combination of the two resistors. The measured voltages may be converted to a resistance ratio and compared to an expected value. In another embodiment, the resistance bridge measurement circuit may be configured to measure a third voltage across the other of the two resistors and a fourth voltage across a combination of the two resistors. The measured voltages may be converted to corresponding resistance ratios, summed and compared to an expected value.

An indicating instrument for a vehicle includes a step motor including a field winding, a pointer, a stopper device for stopping the pointer, which is rotating in a zero-reset direction, at a stopper position, a detecting device for detecting induced voltage of the field winding at each of detecting points, a control device for performing zero-reset control, whereby a drive signal is controlled to rotate the pointer in the zero-reset direction. In a state of abnormal detection in which the induced voltage larger than a predetermined set value is detected at a zero point; and the induced voltage equal to or smaller than the set value is detected at a next detecting point to the zero point, the control device assumes synchronization loss of the step motor and continues the zero-reset control until an assumptive electrical angle corresponding to a rotational position of the pointer reaches the zero point.

Disclosed is a magnetoresistive magnetic field gradient sensor, comprising a substrate, a magnetoresistive bridge and a permanent magnet respectively disposed on the substrate; the magnetoresistive bridge comprises two or more magnetoresistive arms; each magnetoresistive arm consists of one or more magnetoresistive elements; each magnetoresistive element is provided with a magnetic pinning layer; the magnetic pinning layers of all the magnetoresistive elements have the same magnetic moment direction; the permanent magnet is disposed adjacent to each magnetoresistive arm to provide a bias field, and to zero the offset of the response curve of the magnetoresistive element; the magnetoresistive gradiometer includes wire bonding pads that can be electrically interconnected using wire bonding to an ASIC or to the lead frame of a semiconductor chip package.

A constant contact reference wheel system includes a vehicle carrying a water reservoir, and a constant contact reference wheel. The constant contact reference wheel includes a frame having a first end and a second end, an attachment mechanism carried by the first end removably coupling the frame to the vehicle, a wheel structure having a rim for rolling contact with a soil surface, and a reference cell carried by the frame. A water pathway extends from the water source to the rim. The rim exudes water for contact with the soil surface, and the reference cell is in fluid communication with the water pathway.

An aerosol particle spectrometer utilizes a high voltage central electrode and a series of annular, axially arranged collector electrodes maintained at ground, for collecting positively charged particles suspended in an aerosol flowing between the electrodes. Each collector electrode provides current to an integrating electrometer including circuitry that rapidly charges and discharges the integrating capacitor during a brief reset cycle, to generate accurate particle characterizing information based on low currents, with high bandwidth and high dynamic range, virtually in real time.

A method of performing loadflow calculations for controlling voltages and power flow in a power network by reading on-line data of given / specified / scheduled / set network variables / parameters and using control means, so that no component of the power network is overloaded as well as there is no over / under voltage at any nodes in the network following a small or large disturbances. The invented generalized Super Super Decoupled Loadflow (SSDL) calculation method is characterized in that 1) modified real power mismatch at any PQ-node-p is calculated as RPp=[ΔPp′+(Gpp′ / Bpp′)ΔQp′] / Vp2, which takes different form for different manifestation of the generalized version SSDL-X′X′ method, 2) transformed values of known / given / specified / scheduled / set quantities in the diagonal elements of the gain matrix [YV] of the Q-V sub-problem are present, and 3) transformation angles are restricted to maximum of −48° particularly for the most successful version SSDL-YY method, and these inventive loadflow calculation steps together yield some processing acceleration and consequent efficiency gains, and are each individually inventive. The other two Super Super Decoupled Loadflow methods: BGX′ version (SSDL-BGX′) and X′GpvX′ version (SSDL-X′GpvX′) are characterized in the use of simultaneous (1V, 1θ) iteration scheme thereby calculating mismatches only once in each iteration and consequent efficiency gain.

A method of calibrating an individual sensor of a particular sensor type whose output varies non-linearly with at least one measured quantity and at least one operating condition, comprises producing a set of calibration curves for each of a number of sample sensors of the particular sensor type, each curve showing the variation of the sample sensor output with the at least one measured quantity at a different value of the operating condition for the particular sensor type of said individual sensor, said set of curves covering the required operating range for the particular sensor type. The resulting sets of calibration curves of the plurality of sensors derived are then averages and the results used to produce a generic calibration surface for the particular sensor type showing the variation of the sensor reading with the at least one measured quantity across the required operating range. Individual calibration measurements are then taken for a number of different values of the measured quantity for the individual sensor at just a small number of discrete values for the at least one operating condition which fall within the full range of operating values for the at least one operating condition for which the sensor is to be calibrated. The individual calibration readings are then used to map the generic calibration surface to the individual calibration measurements of the individual sensor in order to fit it to the individual sensor.