1642results about How to "Reduce the impact of noise" patented technology

A method and apparatus for reducing the effects of noise on a system for measuring physiological parameters, such as, for example, a pulse oximeter. The method and apparatus of the invention take into account the physical limitations on various physiological parameters being monitored when weighting and averaging a series of measurements. Varying weights are assigned different measurements, measurements are rejected, and the averaging period is adjusted according to the reliability of the measurements. Similarly, calculated values derived from analyzing the measurements are also assigned varying weights and averaged over adjustable periods. More specifically, a general class of filters such as, for example, Kalman filters, is employed in processing the measurements and calculated values. The filters use mathematical models which describe how the physiological parameters change in time, and how these parameters relate to measurement in a noisy environment. The filters adaptively modify a set of averaging weights to optimally estimate the physiological parameters.

A touch sensor includes a touch drive electrode, a touch detection electrode provided opposed to or side by side with the touch drive electrode and forming an electrostatic capacitance between the touch detection electrode and the touch drive electrode, and a touch detection circuit detecting a contact or proximity position of an object on the basis of a detection signal obtained from the touch detection electrode by applying a touch sensor drive signal to the touch drive electrode. The touch drive electrode is split into plural stripe-like electrode patterns. Applying the touch sensor drive signal to part of the electrode patterns forms a drive line at that time. The touch detection circuit performs a detection on the basis of a first detection signal obtained from a first drive line formed in a first period, and a second detection signal obtained from a second drive line formed in a second period.

The invention provides an SAR image registration method based on SIFT and normalized mutual information. The method includes the steps that firstly, a standard image I1 and an image to be registered I2 are input and are respectively pre-processed; secondly, features of the pre-processed image I1 and features of the pre-processed image I2 are extracted according to the MM-SIFT method to acquire initial feature point pairs Fc and SIFT feature vectors Fv1 and Fv2; thirdly, initial matching is carried out through the Fv1 and the Fv2; fourthly, the Fc is screened for the second time according to the RANSAC strategy of a homography matrix model, final correct matching point pairs Fm are acquired, and a registration parameter pr is worked out according to the least square method; fifthly, I2 is subjected to space conversion through affine transformation, and a roughly-registered image I3 is acquired through interpolation and resampling; sixthly, pr serves as the initial value of normalization information registration, I1 and I2 are subjected to fine registration through the normalized mutual information method, a final registration parameter pr1 is worked out, and a registered image I4 is output. The method can be quickly, effectively and stably carried out, and SAR image registration precision and robustness are improved.

Defects in an image forming system may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process direction. A compensation pattern according to this invention has a plurality of halftone regions that are lead by, trained by, and separated by rows of fiducial marks. The fiducial marks allow the printer pixel grid and a scanning pixel grid to be correlated. The gray level in each pixel column of each gray level portion is measured and analyzed to produce a local tone reproduction curve for each pixel column and associated line width. The local tone reproduction curves are then used to compensate for the streak defect when printing.

A linear pre-regulator for cascading with a switching regulator for providing a load current for a circuit or personnel protection device includes a transistor for providing a series variable resistance when a load current changes. The series variable resistance includes a control node, and a control part maintains a substantially fixed voltage at the control node when the current drawn by the switching regulator changes. A storage part may be included to provide a voltage at a drain of a transistor forming the series variable resistance during an OFF-to-ON transition of the transistor.

There is provided a switching power supply device which is capable of reducing an influence of noises and also reducing a consumption current of a control circuit. A pseudo-random number generator circuit (12) generates random number data for determining frequencies of switching signals of MOS transistors (M1) and (M2). A chopping wave oscillation frequency (a frequency of a switching signal) of a chopping wave oscillator (3) randomly changes according to the random number data that is generated by the pseudo-random number generator circuit (12). A current control circuit (1) and a current control circuit (2) control consumption currents that flow in the chopping wave oscillator (3) and an error amplifier (8) according to a change (a change in the frequency of the switching signal) in the random number data that is generated by the pseudo-random number generator circuit (12).

Apparatus, systems and methods of using 70 CFM ventilation fans with heaters for bathrooms having depressibly engageable and depressibly releaseable light covers. The novel ventilation fans and heaters can be mounted to structure in ceilings and inside walls with telescoping suspension brackets that are affixed directly to separate sides of the housing to support the housing against joists and structural supports behind the ceiling. Adjustable louvers on the grill cover allow for outgoing heated air to travel in a different direction into a space from the incoming air travelling into the housing. Plastic type housings around blower wheels reduce undesirable noise effects. The light covers can be easily opened and closed by using depressible engageable fasteners, and depressible release fasteners.

With the objective of definitely generating a biopsy needle on an ultrasonic image, an ultrasonic diagnostic apparatus according to the present invention brings a probe connected thereto into contact with the surface of a body and applies ultrasound thereto, receives signals reflected from within the body and the biopsy needle inserted in the body, and generates ultrasonic images (tomograms) in the body and at the biopsy needle on the basis of the received signals. Picture elements are added every pixels with respect to range-specified portions of these ultrasonic images to thereby generate an ultrasonic image formed by superimposing the respective pixels. Even while the so-superimposed ultrasonic image is being created, ultrasonic images are sequentially stored. The so-superimposed ultrasonic image and the latest ultrasonic image are displayed on an output unit in combination.

The invention relates to an image mosaic method based on neighborhood Zernike pseudo-matrix of characteristic points, which leads image statistical information (Zernike pseudo-matrix) to be interrelated with the characteristic points of an image by using the following steps: firstly, extracting interest points of an inference image and an input image by utilizing a Harris angle detector, and taking rectangular neighborhoods using the interest points as a center as a local characteristic region with characteristic matching; secondly, calculating the Zernike pseudo-matrix to the rectangular characteristic regions to be used as descriptors of the characteristic region, and realizing the matching of the characteristic points through comparing the Euclidean distance of the characteristic vector of the descriptor of each characteristic region. The matching can have less wrong matching points which are eliminated through a RANSAC (RANdom Sample Consensus) algorithm, and the right matching relation can be calculated to realize the image mosaic. The invention can effectively realize the image registration and mosaic with geometric transformation relations of translation, rotation, small scale zooming, and the like, and can be used for image treatment and image synthesis of fields such as communication, multimedia technology, and the like.

A method of operating a metrology instrument includes generating relative motion between a probe and a sample at a scan frequency using an actuator. The method also includes detecting motion of the actuator using a position sensor that exhibits noise in the detected motion, and controlling the position of the actuator using a feedback loop and a feed forward algorithm. In this embodiment, the controlling step attenuates noise in the actuator position compared to noise exhibited by the position sensor over the scan bandwidth. Scan frequencies up to a third of the first scanner resonance frequency or greater than 300 Hz are possible.

Relatively powerful hand-held computing devices, Digital Signal Processors, Audio signal processing technology, voice recognition technology, expert systems, Hidden Markov Models, and/or neural networks are employed in a device capable of real-time automated species identification by listening to bird vocalizations in the field, analyzing their waveforms, and comparing these waveforms against known reference samples. An apparatus for identifying animal species from their vocalizations, comprises a source of digital signal representative of at least one animal candidate vocalization; a feature extractor that receives the digital signal, recognizes notes therein and extracts phrases including plural notes and that produces a parametric representation of the extracted phrases; and a comparison engine that receives the parametric representation of at least one of the digital signal and the extracted phrases, and produces an output signal representing information about the animal candidate based on a likely match between the animal candidate vocalization and known animal vocalizations. A computer-implemented method of identifying animal species, comprises: obtaining a digital signal representing a vocalization by a candidate animal; transforming the digital signal into a parametric representation thereof; extracting from the parametric representation a sequence of notes defining a phrase; comparing the phrase to phrases known to be produced by a plurality of possible animal species; and identifying a most likely match for the vocalization by the candidate animal based upon the comparison. The comparison engine or comparison function may use Hidden Markov Models, expert systems and/or neural networks.

A transformer unit and a power converting device, which lessen the influence of noise caused by an external magnetic flux, while reducing the temperature dependency of a coupling coefficient, and which transfer signals while insulating a low-voltage and a high-voltage side electrically. Air-core type insulated transformers have a first and second winding of a primary winding as a sending side and a first and second winding of a secondary winding as a receiving side. The windings of the primary winding are connected in parallel and are wound so that the directions of magnetic fields generated by an exciting current oppose each other. The windings of the secondary winding are wound so that electromotive forces to be generated by an external magnetic flux cancel each other, and are connected in series so as to raise the electromotive forces by a signal magnetic flux generated by the primary winding.

The present invention relates to voltage measurement apparatus. The voltage measurement apparatus comprises a potential attenuator configured to be electrically connected between first and second conductors, which are electrically coupled to a source. The potential attenuator comprises a first impedance and a reference impedance arrangement in series with each other. The reference impedance arrangement has an electrical characteristic which is changed in a known fashion. The voltage measurement apparatus further comprises a processing arrangement configured: to acquire at least one signal from the reference impedance arrangement, the at least one signal reflecting change of the electrical characteristic in the known fashion; and to determine a voltage between the first and second conductors in dependence on the fashion in which the electrical characteristic is changed being known and the at least one signal.

A sensor unit includes a motion sensor which detects a motion of an object, outputs a detection value, and is mounted on the object through an attachment, a filter which receives the detection value, passes a given frequency band, and is able to change a cutoff frequency of the frequency band, and a control unit which controls the cutoff frequency, wherein the control unit determines the cutoff frequency in accordance with hardness of the attachment.

The invention discloses a method and a system for detection an edge of a blood vessel graphic tissue structure and a blood vessel endangium. The method comprises the following steps: acquiring a two-dimensional ultrasonic blood vessel grayscale image; searching for the central position of a blood vessel on the basis of the structural characteristics of the blood vessel and setting an interesting area; searching a blood vessel cavity and the blood vessel endangium of the interesting area, and/or the initial segmentation boundary between the medial layer of the blood vessel and a blood vessel adventitia, creating an energy functional on the basis of a grayscale distribution function of the segmentation area, and taking the position corresponding to the extreme value of the energy functional as the boundary position between neighbouring areas; and calculating and displaying blood vessel wall parameters. The grayscale distribution-based energy functional is introduced into the detection of the boundary of the tissue structural area; stronger robust estimation is subjected to the edge of the tissue structure by analyzing the grayscale distribution characteristics of each tissue structure; and partial extreme value is avoided.

The embodiments of the invention provide a fault diagnosis method and apparatus for a rolling bearing. The fault diagnosis method for the rolling bearing comprises the following steps: acquiring vibration signals of the rolling bearing, and solving a time-frequency spectrum of the vibration signals; according to the time-frequency spectrum, determining an optimal order component of the vibration signals; according to the optimal order component, performing angle re-sampling on the vibration signals to obtain angle domain signals; and performing envelope analyzing on the angle domain signals, and determining fault positions of the rolling bearing, wherein determination of the optimal order component comprises: setting an equivalent frequency conversion scope and searching for all order components from the time-frequency spectrum; and calculating order energy of the order components and determining the optimal order component from the equivalent frequency conversion scope. The fault diagnosis method and apparatus for the rolling bearing realize automatic and rapid determination of the optimal order component so as to provide a basis for fault diagnosis of the rolling bearing, improve the fault diagnosis accuracy and avoid interference of manual factors.

The invention provides a signal transmission device that transmits a signal applied to a pair of input terminals to a pair of output terminals insulated electrically from the pair of input terminals while reducing the influence of an external noise magnetic field. The signal transmission device has a pair of coils, a pair of magnetic sensors and a signal output section. Each of the coils is connected between the pair of input terminals. Each of the coils generates a magnetic field respectively in response to the input signal applied between the pair of input terminals. A direction of the magnetic field generated by one of the coils is opposite to a direction of the magnetic field generated by the other of the coils. Each of the magnetic sensors corresponds to one of the coils exclusively. Each of the magnetic sensors detects the magnetic field generated by the corresponding coil, and outputs a detection signal in response to the detected magnetic field. The signal output section outputs an output signal to the pair of output terminals. The output signal corresponds to a difference between the pair of detection signals outputted by the pair of magnetic sensors. In the difference, the signal component caused by an external noise magnetic field is canceled. On the other hand, in the difference, the signal component caused by the input signal applied between the pair of input terminals are doubled with respect to the input signal. Thereby, the signal output section outputs the output signal with high S/N ratio.