147 results about "Circumflex" patented technology

A microporous polyolefin battery separator membrane is extremely high in porosity, high in puncture strength, very low in shrinkage and with shutdown temperature of 130–140 degrees C. and melt integrity greater than 165 degrees C. It is made of UHMWPE having a weight-average molecular weight of 1×10⁶ or more and an inert filler. A second microporous polyolefin battery separator has a shutdown temperature of between 95 and 110 degrees C. and a melt integrity of more than 165 degrees C. It is made from an UHMWPE having a weight-average molecular weight of 1×10⁶ or more, a shutdown (LMWPE) having a weight-average molecular weight of 4500 or less and an inert filler. Both membranes have a thickness of 5–75 microns, a porosity of 30–95%, an air permeability of 1–200 sec/10 cc, an average pore diameter of 0.001 to 1 micron and puncture strength of more than 300 grams/25 {circumflex over (l)}¼ m.

A method for tracking coronary artery motion includes constructing (11) a centerline model of a vascular structure in a base phase image in a sequence of 2D images of coronary arteries acquired over a cardiac phase, computing (12), for each pixel in a region-of-interest in each subsequent image, a velocity vector that represent a change in position between the subsequent image and base phase image, calculating (13) positions of control points in each phase using the velocity vectors, and applying (14) PCA to a P×2N data matrix X^T constructed from position vectors (x, y) of N centerline control points for P phases to identify d eigenvectors corresponding to the largest eigenvalues of XX^T to obtain a d-dimensional linear motion model {circumflex over (α)}_p, in which a centerline model for a new image at phase p+1 is estimated by adding {circumflex over (α)}_p to each centerline control point of a previous frame at phase p.

A system and method for obtaining an OIS coordinate frame comprising an electronic control unit configured to determine a local 3D electric field loop, create a zero mean version of E(t) over a depolarization interval, compute an Ė value at each of a plurality of time intervals, compute an initial estimate of ŵ from a cross product of E and the Ė value for each of the plurality of time intervals, average the initial estimate of ŵ from each of the plurality of time for a best estimate of ŵ, determine a plurality of â(θ) values and using the corresponding {circumflex over (n)}(θ) values, compute a composite match score, and choose at least one best value for â and a best value for {circumflex over (n)}.

This invention relates to a system for estimating the position, speed and orientation of a vehicle (10), comprising means for determining the components of two noncollinear constant unit vectors _b, _b according to vehicle body axes; means for determining the components of said noncollinear constant unit vectors {right arrow over (g)}_t, {right arrow over (e)}_t according to Earth's axes; means for determining the three components of angular velocity _b of the vehicle in body axes; means for correcting said angular velocity _b with a correction u_ω and obtaining a corrected angular velocity {circumflex over (ω)}_b=_b+u_ω; a control module (14) implementing a control law to calculate said correction u_ω, where said control law is:

u_ω=σ(_b×ĝ_b+<?img id="custom-character-00007" he="3.13mm" wi="1.78mm" file="US20070213889A1-20070913-P00901.TIF" alt="custom character" img-content="character" img-format="tif" ?>_b×ê_b)  [1]

where σ is a positive scalar,

such that upon using said corrected angular velocity {circumflex over (ω)}_b=_b+u_ω as input to a module for integrating the kinematic equations, the latter are stable in the ISS sense and the error in the estimation of the direction cosine matrix {circumflex over (B)} and of the Euler angles {circumflex over (Φ)} is bounded.

A method of controlling the grid-side current of a single-phase grid-connected converter having an LCL filter connected between the output of the converter and the grid. The method includes measuring a grid voltage (v_S) and at least one signal in a group of signals consisting of a grid-side current (i₀), a converter-side current (i₁) and a capacitor voltage (v_C0). The method includes estimating the fundamental component (v_S,1) of the grid voltage (v_S), forming a grid-side current reference (i₀*), a converter-side current reference (i₁*) and a capacitor voltage reference (v_C0*) for the grid-side current of the LCL filter using the fundamental component of the grid voltage (v_S,1), forming estimates for the non-measured signals in said group of signals, forming a grid-side current difference term (ĩ₀), a converter-side current difference term (ĩ₁) and a capacitor voltage difference term ({tilde over (v)}_C0) from the differences between the references and measured/estimated values of said signals, forming an injection term for damping the resonance of the LCL filter by using an active damping injection mechanism (ADI), in which the grid-side current difference term (ĩ₀), the converter-side current difference term (ĩ₁) and the capacitor voltage difference term ({tilde over (v)}_C0) are used, forming an estimate of harmonic distortion term ({circumflex over (φ)}) using the grid-side current difference term (ĩ₀), and controlling the output voltage (e) of the converter on the basis of the grid voltage, formed injection term and formed estimate of the harmonic distortion term ({circumflex over (φ)}) to produce a grid side (i₀) current corresponding to the current reference.

Disclosed herein is a hybrid error concealment method. The hybrid error concealment method of the present invention includes a first step of calculating a side match distortion, measured when a motion vector for an arbitrary intra-frame is assumed to be zero, and the intra-frame is temporally reconstructed, a second step of applying temporal error concealment when the side match distortion, calculated at the first step, is less than a predetermined low threshold value, a third step of applying spatial error concealment when the side match distortion, calculated at the first step, is greater than a predetermined high threshold value, and a fourth step of performing error concealment based on {circumflex over (m)}{circumflex over (b)}(x,y)=α·{circumflex over (m)}{circumflex over (b)}_t(x,y)+β·{circumflex over (m)}{circumflex over (b)}_s(x,y) when the side match distortion, calculated at the first step, exists between the low threshold value and the high threshold value. According to the present invention, the hybrid error concealment method improves PSNR performance compared to a conventional spatial error concealment algorithm used in H.264, and obtains greatly improved performance characteristics, particularly when motion is small and the value of a quantization parameter is relatively low.

A system and method is provided for estimating a sequence of N bits ({circumflex over (x)}₀{circumflex over (x)}₁ . . . {circumflex over (x)}_N−1) corresponding to a received sequence of M digital data (r₀r₁ . . . r_M−1). The method includes determining candidate sequences of M_RS digital data from a reduced reference sequence space comprising 2^{N<sub2>RS </sub2>}reduced reference sequences of M_RS reference digital data (s₀s₁ . . . s_{M<sub2>RS</sub2>−1}), M_RS being less than M, and 2^{N<sub2>RS </sub2>}being less than or equal to 2^N. The method further includes making up each candidate sequence with remaining reference symbols to obtain at least one complete candidate sequence of M digital data, and determining the sequence of N bits ({circumflex over (x)}₀{circumflex over (x)}₁ . . . {circumflex over (x)}_N−1) from the complete candidate sequences.

An image capturing device may include a detector including a plurality of sensing pixels, and an optical system adapted to project a distorted image of an object within a field of view onto the sensing pixels, wherein the optical system expands the image in a center of the field of view and compresses the image in a periphery of the field of view, wherein a first number of sensing pixels required to realize a maximal zoom magnification {circumflex over (Z)} at a minimum resolution of the image capturing device is less than a square of the maximal zoom magnification times a second number of sensing pixels required for the minimum resolution.

The invention relates to a code-tracking method and a rake receiver for CDMA communication systems of low complexity yielding stable tracking. Received signal are distributed to a plurality of receiver fingers of a rake receiver. Each receiver finger i is assigned to a signal path of the transmitted signal which is subject to phase shift and power dissipation due to reflection, diffraction and scattering. According to the invention in each receiver finger i an estimation of the timing delay {circumflex over (τ)}⁽ⁱ⁾ is provided and interference from other signal components j are subtracted from signal components of the current signal path i (i≠j) yielding a reliable estimated timing delay {circumflex over (τ)}.

A method for sensorless estimation of rotor speed and position of a permanent magnet synchronous machine the method comprising the steps of calculating first stator flux vector estimate ({circumflex over (ψ)}_d,i+j{circumflex over (ψ)}_q,i) using the flux model and measured stator currents, calculating second stator flux vector estimate ({circumflex over (ψ)}_d,u+j{circumflex over (ψ)}_q,u) using the voltage model and measured stator voltages, comparing the directions of the first and second flux vectors to achieve a first error signal (F_ε), using speed adaptation to achieve estimates for the rotor angular speed ({circumflex over (ω)}_m) and angular position ({circumflex over (θ)}_m) from the first error signal (F_ε), injecting a known voltage signal (u_c) to the stator voltage, detecting a current signal (i_qc) from the stator current to form a second error (ε) signal, which is dependent on the estimation error of the rotor position, augmenting the voltage model by the second error signal (ε) to keep the first and second flux vector estimates aligned and so to correct the rotor angular speed ({circumflex over (ω)}_m) and angular position ({circumflex over (θ)}_m) estimates.

A method for the online determination of values of driving dynamics for a motor vehicle. To improve the quality of the control of a motor vehicle and to reduce the demands placed on the driver, the invention discloses a driving dynamics control including the (1) estimated output quantities ŷ_m in dependence on determined or estimated input quantities u and predetermined or predicted vehicle state variables {circumflex over (x)} and optionally further quantities, (2) comparing the estimated output quantities ŷ_m with measured output quantities y_m, and (3) determining the estimated driving dynamics quantities {circumflex over (x)}(t_k/t_k) in dependence on the measurement result and, as the case may be, further criteria.

A main vector: m{circumflex over ( )}=(mx, my) and a sub-vector: s{circumflex over ( )}=(sx, sy) determining cyclic structure of a basic matrix are defined, and a positional vector for a pixel configuring the basic matrix Pi{circumflex over ( )}=(Pix, Piy) is defined, where the suffix i denotes an i-th pixel configuring the basic matrix. Then, the pixels configuring the basic matrix are arranged in such a manner as to satisfy the cyclic structure, and transformation of Pi{circumflex over ( )}→Pi{circumflex over ( )}+km{circumflex over ( )}+ls{circumflex over ( )} is carried out where k and l are arbitrary integers, and may be negative values. Then a new shape of the basic matrix is obtained with Pi{circumflex over ( )}+km{circumflex over ( )}+ls{circumflex over ( )} as a new pixel positional vector Pi{circumflex over ( )}.

A method and system is disclosed for clock synchronization in a wireless backhaul network, based on the IEEE1588 Precision Time Protocol (PTP). The network comprises a plurality of hubs, each hub serving one or more remote backhaul modules. Each hub comprises a slave clock, which communicates with a master clock through forward and reverse links. The method comprises, for each hub, estimating the frequency drift {circumflex over (α)} and offset {circumflex over (β)} from the forward and reverse links between the master and slave clock, estimating the accuracy of {circumflex over (α)} and {circumflex over (β)}, determining the least congested link, and adjusting the frequency of the slave clock based on {circumflex over (α)} and {circumflex over (β)} from the least congested link. A fixed or variable time window size is selected to achieve a desired accuracy of {circumflex over (α)} and {circumflex over (β)}. The method may comprise estimating a maximum holdover time for maintaining synchronization with a desired confidence level.

A method and system for eliminating echo in a speaker-microphone communication system are provided. The method includes the steps of: performing a noise energy estimating process on a local microphone signal in order to obtain an estimated noise signal, wherein the local microphone signal includes a local voice signal, possible background noise signal, and possible remote voice signal output from a speaker and received by a microphone; performing an echo estimating process on a remote voice signal to obtain an estimated echo signal, wherein the remote voice signal is output from the speaker; determining an error signal from the local microphone signal and the estimated echo signal; calculating a variance (σ_e²) of the error signal and a variance ({circumflex over (σ)}_n²) of the estimated noise signal; calculating a determinant (ξ), wherein the determinant (ξ) corresponds to the variance (σ_e²) of the error signal and variance ({circumflex over (σ)}_n²) of the estimated noise signal; and comparing the determinant (ξ) and a preset threshold, wherein when the determinant (ξ) is lower than the preset threshold, it is determined that double-end talk has not occurred, otherwise, it is determined that double-end talk has occurred.

A method for segmenting an object of interest from an image of a patient having such object. Each one of a plurality of training shapes is distorted to overlay a reference shape with a parameter Thetai being a measure of the amount of distortion required to effect the overlay. A vector of the parameters Thetai is obtained for every one of the training shapes through the minimization of a cost function along with an estimate of uncertainty for every one of the obtained vectors of parameters Thetai, such uncertainty being quantified as a covariance matrix Sigmai. A statistical model represented as {circumflex over (f)}H (Theta,Sigma) is generated with the sum of kernels having a mean Thetai and covariance Sigmai . The desired object of interest in the image of the patient is identified by positioning of the reference shape on the image and distorting the reference shape to overlay the obtained image with a parameter Theta being a measure of the amount of distortion required to effect the overlay. An uncertainty is quantified as a covariance matrix Sigma and an energy function E=Eshape+Eimage is computed to obtain the probability of the current shape in the statistical shape model Eshape(Theta,Sigma)=-log({circumflex over (f)}H) and the fit in the image Eimage.

A circuit and a method for performing pulse width modulation are provided. A pulse density modulator (PDM) is applied to receive the least N bits of the input data and to generate a pulse density modulation signal. The number of pulse of the pulse density modulation signal in 2{circumflex over ( )}N frames correspond to a value of the least N bits of the input data. An adder is applied to generate a PWM data by adding a value of the most M bits of the input data to a value of the pulse density modulation signal generated by the PDM. A pulse width modulator is applied to generate a PWM signal dithering in 2{circumflex over ( )}N frames according to the PWM data generated by the adder, so as to improve the audio quality of pulse width modulation and the Electro-Magnetic Interference (EMI) phenomenon.

The present invention, which addresses the needs described above, resides in an apparatus and method for coupling vascular apertures to a blood supply vessel in a manner that minimizes the time and operator dependent inconsistency in performing vascular anastomoses. In the coronary setting, this concept is fast and can be applied to both conventional and minimally invasive operative techniques. In the preferred embodiment, the present invention relates to an apparatus and method for facilitating end-to-side vascular anastomoses procedure, whereby the present invention acts as a coupling apparatus between a first, blood supplying hollow organ, e.g. the LIMA, radial artery, or a saphenous vein and the side wall of second hollow organ, typically one of the major coronary arteries, such as the left coronary artery (LCA), right coronary artery (RCA) or the circumflex (CX).

Providing a pilot aided phase recovery of a carrier of an input digital signal Z_k having signal fields of L_s symbol signals, L_P pilot symbol signals Z^P_(k) and (L_s−L_P) data symbol signals Z^d_(k), by for each signal field:

• • calculating an unwrapped pilot phase estimate {circumflex over (θ)}_f^(P)(l);
  • initiating with {circumflex over (θ)}_f^(P)(l) a first digital phase locked loop implementing a phase estimate algorithm and calculating a forward phase trajectory {circumflex over (θ)}_F(k) from Z^d_(k), ks varying between 1 and L_s−L_P over the data field (l), {circumflex over (θ)}_F^(P)(l) having L_s−L_P forward phase estimates {circumflex over (θ)}_F(ks);
  • and initiating with {circumflex over (θ)}^(P)_f(l+1) a second digital phase locked loop, implementing a phase estimate algorithm and calculating a backward phase trajectory {circumflex over (θ)}_B(ks) from Z^d(k), ks varying between L_s−L_P and 1 over said data field (l), {circumflex over (θ)}_B(ks) having L_s−L_P backward phase estimates {circumflex over (θ)}_B(ks); and
  • from said phase trajectories calculating a phase correction (e^{−j{circumflex over (θ)}(ks)}).

A method of controlling of an induction machine using an inverter is disclosed with output LC filter. The method includes determining an inverter output current vector (i_A), determining an inverter output voltage vector (u_A), and forming a full-order observer having a system matrix (Â) and gain vector (K). The observer produces an estimated rotor flux linkage vector ({circumflex over (ψ)}_R), an estimated stator current vector (î_s), an estimated stator voltage vector (û_s) and an estimated inverter output current vector (î_A). An estimation error (i_A-î_A) of the inverter output current vector is determined, and a speed adaptation law is formed based on the estimation error of the inverter output current vector for determining an estimate for electrical angular speed ({circumflex over (ω)}_m) of the induction machine. The induction machine is controlled based on the produced estimates and a measured inverter output current.