12835 results about "Estimation methods" patented technology

Systems and methods for minimizing or eliminating transient non-glucose related signal noise due to non-glucose rate limiting phenomenon such as ischemia, pH changes, temperatures changes, and the like. The system monitors a data stream from a glucose sensor and detects signal artifacts that have higher amplitude than electronic or diffusion-related system noise. The system replaces some or the entire data stream continually or intermittently including signal estimation methods that particularly address transient signal artifacts. The system is also capable of detecting the severity of the signal artifacts and selectively applying one or more signal estimation algorithm factors responsive to the severity of the signal artifacts, which includes selectively applying distinct sets of parameters to a signal estimation algorithm or selectively applying distinct signal estimation algorithms.

Systems and methods for minimizing or eliminating transient non-glucose related signal noise due to non-glucose rate limiting phenomenon such as ischemia, pH changes, temperatures changes, and the like. The system monitors a data stream from a glucose sensor and detects signal artifacts that have higher amplitude than electronic or diffusion-related system noise. The system replaces some or the entire data stream continually or intermittently including signal estimation methods that particularly address transient signal artifacts. The system is also capable of detecting the severity of the signal artifacts and selectively applying one or more signal estimation algorithm factors responsive to the severity of the signal artifacts, which includes selectively applying distinct sets of parameters to a signal estimation algorithm or selectively applying distinct signal estimation algorithms.

A method and apparatus for controlling a ventricular assist device are disclosed. The method includes the step of providing a ventricular assist device which can be defined in terms of operational parameters such as pump speed or current. Measuring at least one physiological parameter reflecting a physiological state corresponding to a patient. Correlating at least one physiological parameter measured from the patient to at least one operational parameter using an estimation method. Selecting a physiological state definable by desired values of the physiological parameters. Monitoring at least one operational parameter. Controlling input values of the operational parameter based on output from the monitoring step. The apparatus includes a pump driven by a motive drive and having an impeller. A sensor detects the value of an operational parameter of the pump. A processor provides a statistical correlation between patients physiological parameter and the operational parameter of the pump and adjusts the operational parameter to affect a predetermined optimal physiological state.

The focal length estimation method and apparatus claimed in this application aligns plural overlapping images with one another for constructing an image mosaic. This is accomplished by computing a planar perspective transformation between each overlapping pair of the images, computing from the planar perspective transformation a focal length of each image of the pair, computing from the focal length of each image a focal length transformation, computing a rotational transformation for each of the pair of images whereby a combination of the rotational transformation and the focal length transformation relates the respective image to a three-dimensional coordinate system. Registration errors between the pair of images are reduced by incrementally deforming the rotational transformation of one of the pair of images. The planar perspective transform is a matrix of warp elements, and the focal length is computed as a function of the warp elements, the function being derivable by constraining a first two rows or the first two columns of the matrix to have the same norm and to be orthogonal. The focal length of one image of a pair of images is found by applying the constraint on the matrix columns, while the focal length of the other image of the pair is found by applying the constraint on the matrix rows

System for improving a performance estimation of an operator of a vehicle, comprising a first module implementing a first method for estimating a performance state of vehicle operation, a second module implementing a second method for estimating at least one of a physiological and behavioural state of the operator, a device for sharing an estimated state between one of the first and the second module and the other one of the first and the second module, wherein the implemented estimation method of one of the first and the second module is adjusted based on the state of the other one of the first and the second module, thereby improving the estimation of at least one of the performance state of vehicle operation and the physiological and / or behavioural state of the operator.

A method and apparatus are provided for reducing the number of pilot symbols within a MIMO-OFDM communication system, and for improving channel estimation within such a system. For each transmitting antenna in an OFDM transmitter, pilot symbols are encoded so as to be unique to the transmitting antenna. The encoded pilot symbols are then inserted into an OFDM frame to form a diamond lattice, the diamond lattices for the different transmitting antennae using the same frequencies but being offset from each other by a single symbol in the time domain. At the OFDM receiver, a channel response is estimated for a symbol central to each diamond of the diamond lattice using a two-dimensional interpolation. The estimated channel responses are smoothed in the frequency domain. The channel responses of remaining symbols are then estimated by interpolation in the frequency domain.

Methods and apparatus are provided for inserting data symbols and pilot symbols in an OFDM (orthogonal frequency division multiplexing) transmission resource utilizing frequency hopping patterns for the data symbols and / or the pilot symbols. Data symbols and pilot symbols are allocated for down link (base station to mobile station) and up link (mobile station to bases station) transmission resources in a two-dimensional time-frequency pattern. For each antenna of a MIMO-OFDM (multiple input multiple output OFDM) communication system, pilot symbols are inserted in a scattered pattern in time-frequency and data symbols are inserted in an identical frequency-hopping pattern in time-frequency as that of other antennas.

Conventional position estimation methods require the deployment of more fixed anchors in order to increase the accuracy in a crowded indoor environment, or they suffer from inaccuracies due to multipath fading. The present invention overcomes the problems associated with the prior arts by selecting one or more mobile nodes as virtual anchors when estimating the position of a target mobile node. This takes advantage of the fact that mobile nodes are closer to the target mobile node than the access points in most typical deployments, thus eliminating the need to deploy more access points or fixed anchors for the purpose of position determination. After obtaining an initial estimate of the position of the target mobile node, the target mobile node can serve as virtual anchors to estimate the positions of other mobile nodes, which can then be used to further refine the position estimate of the target mobile node.

An electronic scanning type radar device mounted on a moving body includes: a transmission unit transmitting a transmission wave; a reception unit comprising a plurality of antennas receiving a reflection wave of the transmission wave from a target; a beat signal generation unit generating a beat signal from the transmission wave and the reflection wave; a frequency resolution processing unit frequency computing a complex number data; a target detection unit detecting an existence of the target; a correlation matrix computation unit computing a correlation matrix from each of a complex number data of a detected beat frequency; a target consolidation processing unit linking the target in a present detection cycle and a past detection cycle; a correlation matrix filtering unit generating an averaged correlation matrix by weighted averaging a correlation matrix of a target in the present detection cycle and a correlation matrix of a related target in the past detection cycle; and a direction detection unit computing an arrival direction of the reflection wave based on the averaged correlation matrix.

Methods for estimating genomic copy number and loss of heterozygosity using Hidden Markov Model based estimation are disclosed.

Methods and apparatus for estimating mobile station location include receiving reported signal strengths or other attachment indicator values from a mobile station. The reported signal strengths are compared with characteristic received signal strength values in a coverage area of a mobile network. A mobile switching center determines if a location function is requested and initiates a location estimation process by a mobile location module (MLM). The MLM receives the reported signal strength contours associated with the attachment points. Based on a comparison of the reported attachment indicator values with characteristic values, the MLM provides a mobile location estimate.

The invention discloses a machine vision and inertial navigation fusion-based mobile robot motion attitude estimation method which comprises the following steps of: synchronously acquiring a mobile robot binocular camera image and triaxial inertial navigation data; distilling front / back frame image characteristics and matching estimation motion attitude; computing a pitch angle and a roll angle by inertial navigation; building a kalman filter model to estimate to fuse vision and inertial navigation attitude; adaptively adjusting a filter parameter according to estimation variance; and carrying out accumulated dead reckoning of attitude correction. According to the method, a real-time expanding kalman filter attitude estimation model is provided, the combination of inertial navigation and gravity acceleration direction is taken as supplement, three-direction attitude estimation of a visual speedometer is decoupled, and the accumulated error of the attitude estimation is corrected; and the filter parameter is adjusted by fuzzy logic according to motion state, the self-adaptive filtering estimation is realized, the influence of acceleration noise is reduced, and the positioning precision and robustness of the visual speedometer is effectively improved.

A method and apparatus are provided for encoding and decoding a multi-view moving picture. A method of estimating a disparity vector to encode a multi-view moving picture includes: estimating disparity vectors for a predetermined number of encoded macroblocks; and calculating disparity vectors of macroblocks adjacent to the encoded macroblocks using the estimated disparity vectors. Therefore, it is possible to quickly perform encoding of a multi-view moving picture and enhance compressibility of the multi-view moving picture.

An estimated total camera motion between temporally proximate image frames is computed. A desired component of the estimated total camera motion is determined including distinguishing an undesired component of the estimated total camera motion, and including characterizing vector values of motion between the image frames. A counter is incremented for each pixel group having a summed luminance that is greater than a threshold. A counter may be decremented for pixels that are under a second threshold, or a zero bit may be applied to pixels below a single threshold. The threshold or thresholds is / are determined based on a dynamic luminance range of the sequence. The desired camera motion is computed including representing the vector values based on final values of counts for the image frames. A corrected image sequence is generated including the desired component of the estimated total camera motion, and excluding the undesired component.

Systems and methods for distance measurement in wireless networks are disclosed. A method for measuring distance between nodes or devices in a wireless network comprises estimating a distance between network devices based on a first distance measurement method, estimating the distance based on a second distance measurement method, and processing the first and second distance estimates to determine convergence and to generate an enhanced distance measurement. Additional distance estimates may be combined to further improve accuracy. Convergence information may be provided indicating whether two or more distance estimates converge. In some implementations, the first distance estimate may be generated by a transmission time estimation method, the second distance estimate may be generated by a received signal strength distance estimate, the two estimates may be combined by averaging to generate an enhanced distance estimate, and the difference between the estimates may be compared to a threshold to determine whether the estimates have sufficiently converged to within a desired convergence range.

The invention provides a combined estimation method for lithium ion battery state of charge, state of health and state of function. The combined estimation method comprises the steps that the state of he---alth of a battery is estimated online: open circuit voltage and internal resistance are identified online by adopting a recursive least square method with a forgetting factor, the state of charge is indirectly acquired according to a pre-established OCV-SOC corresponding relation, and then the size of battery capacity is estimated according to cumulative charge and discharge electric charge between two SOC points; the state of charge of the battery is estimated online: the state of charge of the battery is estimated by adopting the Kalman filter algorithm based on a two-order RC equivalent circuit model, and the battery capacity parameter in the Kalman filter algorithm is updated according to the estimation result of battery capacity; and the state of function of the battery is estimated online: the maximum chargeable and dischargeable current is calculated based on the voltage limit and the current limit of the battery according to internal resistance obtained by online identification, and then the maximum chargeable and dischargeable function can be obtained through further calculation.

Disclosed is a multi-dimensional selectivity estimation method using compressed histogram information which the database query optimizer in a database management system uses to find the most efficient execution plan among all possible plans. The method includes the several steps to generate a large number of small-sized multi-dimensional histogram buckets, sampling DCT coefficients which have high values with high probability, compressing information from the multi-dimensional histogram buckets using a multi-dimensional discrete cosine transform(DCT) and storing compressed information, and estimating the query selectivity by using compressed and stored histogram information as the statistics.

Disclosed in the invention is an improved method of a RGB-D-based simultaneously localization and mapping (SLAM) algorithm. The method comprises two parts: a front-end part and a rear-end part. The front-end part is as follows: feature detection and descriptor extraction, feature matching, motion conversion estimation, and motion conversion optimization. And the rear-end part is as follows: a 6-D motion conversion relation initialization pose graph obtained by the front-end part is used for carrying out closed-loop detection to add a closed-loop constraint condition; a non-linear error function optimization method is used for carrying out pose graph optimization to obtain a global optimal camera pose and a camera motion track; and three-dimensional environment reconstruction is carried out. According to the invention, the feature detection and descriptor extraction are carried out by using an ORB method and feature points with illegal depth information are filtered; bidirectional feature matching is carried out by using a FLANN-based KNN method and a matching result is optimized by using homography matrix conversion; a precise inliners matching point pair is obtained by using an improved RANSAC motion conversion estimation method; and the speed and precision of point cloud registration are improved by using a GICP-based motion conversion optimization method.

Methods of improving channel estimation are described, in which pilot symbols are inserted into orthogonal frequency division multiplexing (OFDM) frames at an OFDM transmitter having at least one transmitting antenna, wherein for the or each antenna, historical data regarding channel conditions is obtained so that the scattered pilot symbols are inserted in a scattered pattern dependent upon said historical data. Alternatively, or in addition, an adaptive channel estimation filter is used whose parameters are selected according to analysis of historical data regarding channel conditions.

An average signal point amplitude detection section 15A determines an average position of I and Q components when a received QPSK modulated signal is demodulated and a threshold calculation section 15B determines threshold ths on an IQ plane based on the average signal point position of the received QPSK modulated signal and a theoretical distribution position on the IQ plane of signal points of a 16-value QAM signal. Then, a threshold decision section 14A makes a threshold-decision on the I and Q components of sequentially received QPSK modulated signals using this threshold ths and thereby calculates a simulated bit error rate of the 16-value QAM signal.

A transmitting apparatus, receiving apparatus, communication system, and a signal processing method of each applying a suitable modulation method and transmission path estimation method in accordance with characteristics of the transmission information for improving the transmission efficiency operate so that at the transmission side, the ratio of adding transmission path estimation pilot symbols is suitably controlled in accordance with an aspect of the dat transmitted, for example, the size of the packets transmitted and the state of the transmission path, wherein the transmission data is mapped by the selected modulation method, and the signal is processed in accordance with the method of estimation of the transmission path, and the transmission signal is produced by inverse fast Fourier transform processing and transmitted. At the reception side, the received signal is fast Fourier transformed, the transmission path is estimated by the transmission path estimation method selected at the transmission side, the received signal is correct in accordance with result, and the received data is reproduced in accordance with the modulation method. Therefore, it is possible to always adopt the optimum transmission method in accordance with the attribute of the transmission data etc. and possible to realize an improvement of a transmission efficiency and an enhancement of the quality of communication.

The invention discloses a full convolution neural network (FCN)-based monocular image depth estimation method. The method comprises the steps of acquiring training image data; inputting the training image data into a full convolution neural network (FCN), and sequentially outputting through pooling layers to obtain a characteristic image; subjecting each characteristic image outputted by a last pooling layer sequentially to amplification treatment to obtain a new characteristic image the same with the dimension of a characteristic image outputted by a previous pooling layer, and fusing the twocharacteristic images; sequentially fusing the outputted characteristic image of each pooling layer from back to front so as to obtain a final prediction depth image; training the parameters of the full convolution neural network (FCN) by utilizing a random gradient descent method (SGD) during training; acquiring an RGB image required for depth prediction, and inputting the RGB image into the well trained full convolution neural network (FCN) so as to obtain a corresponding prediction depth image. According to the method, the problem that the resolution of an output image is low in the convolution process can be solved. By adopting the form of the full convolution neural network, a full-connection layer is removed. The number of parameters in the network is effectively reduced.

This invention relates to a mixed reality presentation apparatus for obtaining the position and orientation of an image sensing unit using markers. Whether or not a marker detected in a captured image has suspicion of partial occlusion is determined by checking if a region that neighbors a marker region includes a predetermined color, thus inhibiting information obtained from the marker with suspicion of partial occlusion from being used in position and orientation estimation of the image sensing unit. The precision of the obtained position and orientation can be improved.

Methods and systems for predicting a cell capacity associated with a cell of an electrochemical cell system are provided. In one exemplary embodiment, the method determines a first predicate cell capacity of the cell of the electrochemical cell system. The method further includes measuring a voltage of the cell to obtain a measured voltage. The method further includes determining a corrected predicted cell capacity of the cell based on the first predicted cell capacity, the measured voltage, and a gain factor.

The invention provides a pose estimation method based on RGB-D and IMU information fusion. The method comprises the following steps: S1, after time synchronization of RGB-D camera data and IMU data, the gray image and depth image acquired by the RGB-D camera and the acceleration and angular velocity information collected by the IMU are preprocessed to obtain the characteristics of adjacent frame matching in the world coordinate system. Point and IMU state increment; S2, a visual inertial device in a system is initialized according to system external parameters of a pose estimation system; S3,according to information of the intilized visual inertial device, feature points matching adjacent frames in a global corrdinate system, least squares optimization functions of an IMU state incrementconstruction system; an optimization method is used to iteratively solve the optimal solution of the least squares optimization function, and the optimal solution is used as the pose estimation statequantity; further, loop detection is performed to acquire globally-consistent pose estimation state quantity. Therefore, feature point depth estimation is more accurate, and positioning precision of the system is improved.

The invention discloses a human body attitude calculation method based on quaternion and Kalman filtering. The method comprises determining a vector coordinate system and a navigation coordinate system, determining an attitude matrix, respectively acquiring accelerated speed, angular velocity and magnetic induction intensity signals through an accelerometer, a gyroscope and a magnetometer, carrying out initial alignment on a human body attitude detection system, calculating initial attitude angles such as a pitching angle, a rolling angle and a heading angle, transforming the initial attitude angles into initial quaternion, carrying out system modeling according to a quaternion differential equation, inputting the initial quaternion as a measured value, carrying out data fusion on the attitude data through a Kalman filtering algorithm, outputting an estimated value which is updated quaternion, carrying out normalization processing on the updated quaternion to obtain final posture information, updating the attitude matrix and acquiring updated attitude angles. The human body attitude estimation method effectively improves the accuracy of human posture detection, has a fast response speed, has good stability and instantaneity and has a broad application prospect.

A transmitting apparatus, receiving apparatus, communication system, and a signal processing method for each apply a suitable modulation method and transmission path estimation method in accordance with the characteristics of the transmission information and capable of improving the transmission efficiency. At the transmission side, the method of estimation of the transmission path and the modulation method are selected in accordance with an attribute of the data to be transmitted, for example, the size of a packet to be transmitted, the transmission data is mapped by the selected modulation method, the signal is processed in accordance with the transmission path estimation method, and a transmission signal is created by increase fast Fourier transform processing and transmitted. At the reception side, the received signal is fast Fourier transformed, the transmission path is estimated by the transmission path estimation method selected at the transmission side, the received signal is corrected in accordance with the result, and the received data is reproduced in accordance with the modulation method. Therefore, it is possible to always adopt the optimum transmission method in accordance with the attribute of the transmission data etc. and possible to realize an improvement of a transmission efficiency and an enhancement of the quality of communication.

The invention discloses a gaze estimation method. The gaze estimation method comprises the following steps: finding out calibration error by aligning; then estimating the distance between a face plane and a screen and establishing a three-dimensional model to obtain optical axis information of eyeballs by offset correction of the head and rotary correction of the head; and finally, obtaining the position of a fixation point. According to the gaze estimation method, only a camera is used and no auxiliary equipment is needed; the aim of furthering increasing the estimation precision is achieved by using a correction link by a user; in addition, due to the utilization of estimation of the distance between the face plane and the screen and the offset and rotation correction of the head, limiting conditions are reduced as much as possible, a comfortable use environment for a user is provided and the gaze estimation method has better precision and adaptability of the head motion; and on the basis of an eyeball of a human eye, the gaze estimation method based on a three-dimensional model is established so as to achieve the aim of increasing the estimation precision. According to the gaze estimation method, extra auxiliary equipment is reduced, the adaptability to the head motion is improved, and the better precision for sight light estimation is obtained.