731 results about "Angular frequency" patented technology

To provide an induced power transmission circuit that transmits, from a transmission antenna (1) connected to a power supply circuit, an AC power having an angular frequency ω to a spaced reception antenna (2) with an excellent efficiency, thereby transmitting it to a load circuit. The induced power transmission circuit comprises a circuit the two ends of which are coupled by a capacitor (C1) and in which the power supply circuit is connected in series to a midway port (1) (P1) of the transmission antenna (1) having an effective self-inductance L1; and a circuit the two ends of which are coupled by a capacitor (C2) and in which the load circuit is connected in series to a midway port (2) (P2) of the reception antenna (2) having an effective self-inductance L2; wherein for a coupling coefficient k of the electromagnetic induction between the antennas and for a phase angle β having an arbitrary value, the angular frequency ω is set to the square root of the reciprocal of a value of L2×C2×(1+k*cos (β)), the output impedance of the power supply circuit is set to approximately kωL1*sin (β), and the input impedance of the load circuit is set to approximately kωL2*sin (β). There is also provided an impedance converting circuit that converts the circuit impedances.

Method and apparatus for radiance processing by demultiplexing in the frequency domain. A frequency domain demultiplexing module obtains a radiance image captured with a lens-based radiance camera. The image includes optically mixed spatial and angular frequency components of light from a scene. The module performs frequency domain demultiplexing on the radiance image to generate multiple parallax views of the scene. The method may extract multiple slices at different angular frequencies from a Fourier transform of the radiance image, apply a Fourier transform to each of the multiple slices to generate intermediate images, stack the intermediate images to form a 3- or 4-dimensional image, apply an inverse Fourier transform along angular dimension(s) of the 3- or 4-dimensional image, and unstack the transformed 3- or 4-dimensional image to obtain the multiple parallax views. During the method, phase correction may be performed to determine the centers of the intermediate images.

A method characterized by making modulated light having a predetermined modulation frequency component, incident to a scattering medium, receiving the modulated light having propagated inside the scattering medium to acquire measurement signals, detecting signals of the foregoing modulation frequency component from the measurement signals, obtaining amplitudes and inclinations of phase against modulation angular frequency, of the signals of the foregoing modulation frequency component, calculating a difference between absorption coefficients being primary information, based on a predetermined relation among the amplitudes, the inclinations of phase against modulation angular frequency and the difference between absorption coefficients, and calculating a difference of concentration of an absorptive constituent being secondary information, based on the difference between absorption coefficients.

The invention belongs to the technical field of digital signal processing, and provides a high-efficiency measurement method of a sinusoidal signal frequency in undersampling and an implementation device which can estimate parameters such as frequency and the like under the condition of undersampling and can finish precise frequency measurement. The invention adopts the technical scheme that traditional FFT spectrum analysis and all phase FFT spectrum analysis are adopted to obtain a peak value spectrum G (q) and a peak value spectrum Ga (q); a phase value is directly read from the peak valuespectrum to take the square of a G (q) modulus to obtain a power spectrum value Pg (q); after performing modulus division on Pg (q) and Ga (q), amplitude estimation is obtained to take the differenceof the phase value of G (q) and the phase value of g(q), and the difference divided by tau=(N-1) / 2 to obtain frequency offset estimation delta k; and finally delta k delta omega and q delta omega aresuperposed to obtain digital angular frequency estimation which directly serves as the phase estimation and the amplitude estimation of the measured signal. The invention is mainly used for undersampling measurement in digital signal processing.

A technology of acquiring and processing light field data for images is provided. A light field data acquisition apparatus includes a modulator with an attenuation pattern to spatially modulate a 4D light field for an image, and a sensor to acquire 2D signals of the spatially modulated 4D light field. By utilizing the attenuation pattern of the modulator, more spatial data may be acquired in a low angular frequency region than that acquired in a high angular frequency region.

A signal processor is configured to perform a process equivalent to performing a series of fixed-to-rotating coordinate conversion, a predetermined process and then rotating-to-fixed coordinate conversion, while maintaining linearity and time-invariance. The signal processor performs a process given by the following matrix G:G=[F(s+jω0)+F(s-jω0)2F(s+jω0)-F(s-jω0)2j-F(s+jω0)-F(s-jω0)2jF(s+jω0)+F(s-jω0)2]where F(s) is a transfer function representing the predetermined process, ω0 is a predetermined angular frequency and j is the imaginary unit.

A method and an apparatus for aligning a phased array antenna, and a phased array antenna are provided. A method for aligning a phased array antenna according to an embodiment of the present invention includes: receiving signals from respective antenna array subunits; performing phase shifting on the signals from the respective antenna array subunits, combining phase-shifted signals, where the signals are from the respective antenna array subunits, and obtaining a first signal, where a receiving beam corresponding to the first signal is a rotating receiving beam; rotating, by the rotating receiving beam, around a transmitting / receiving beam according to a preset angular frequency by using the transmitting / receiving beam as a rotation axis; calculating power values of respective first signals in a case that the rotating receiving beam rotates through different angles; and adjusting, according to the power values, a direction of the transmitting / receiving beam to align a phased array antenna.

The invention is an apparatus used for measuring flexible material flexural fatigue, with property of being consisted of crank block rack mechanism, force and displacement sensor, upper and lower cartridge, optical plummet centering system, up-and-down and rotation driving system and control circuit, program and signal collection system, finishing measurement of fixed point flexural fatigue and relaxation creep behaviour of flexible material with stationary load and stretch effectively and accurately. The index property measured are endurance failure time, endurance limit strength and limiting strain, relaxation time, sample thickness or diameter. The apparatus has simple but practical structure, convenient installation and replacement, many tunable parameters containing sample length, fixed points position and their distance, bending rotational angle and angular frequency, original load and stretch, accurate measurement, and can avoid influence of move of application point in bending, offset of sample and vibration.

An external mask-based radiance camera may be based on an external, non-refractive mask located in front of the main camera lens. The mask modulates, but does not refract, light. The camera multiplexes radiance in the frequency domain by optically mixing different spatial and angular frequency components of light. The mask may, for example, be a mesh of opaque linear elements, which collectively form a grid, an opaque medium with transparent openings, such as circles, or a pinhole mask. Other types of masks may be used. Light may be modulated by the mask and received at the main lens of a camera. The main lens may be focused on a plane between the mask and the main lens. The received light is refracted by the main lens onto a photosensor of the camera. The photosensor may capture the received light to generate a radiance image of the scene.

An electric power steering system includes: a band-stop filter 15a having a transfer function G1(s) for suppressing resonance, and a phase compensator 15b having a transfer function G2(s). The above function G1(s) is represented by an expression G1(s)=(s2+2ζ11ω1+ω12) / (s2+2ζ12ω1+ω12), where s: a Laplace operator, ζ11: a damping coefficient, ζ12: a damping coefficient, and ω1: an angular frequency. On the other hand, the above function G2(s) is represented by an expression G2(s)=(s2+2ζ21ω2+ω22) / (s2+2ζ22ω2+ω22), where s: a Laplace operator, ζ21: a damping coefficient, ζ22: a damping coefficient, and ω1: an angular frequency. Furthermore, the above damping coefficients ζ21, ζ22 satisfy an expression ζ2124 ζ22≧1. Thus, a filter such as a phase compensator may attain a design freedom while preventing the increase of arithmetic load, whereby both the suppression of resonance and a good assist response in a normal steering speed region, for example, may be achieved.

Effects of diffraction of a spectral beam from an edge of the micromirrors are reduced in order to optimize the passband in a wavelength selective switch. The effects of diffraction on the pass band may be reduced by appropriate modification of the edges of the micromirrors, by modification of the input and / or output ports to allow for attenuation by rotation of the micromirror about the switching axis, by using rotation of the micromirror about both the attenuation axis and the switching axis to achieve the desired level of attenuation, by inserting an aperture at a focal plane or external to the device to reduce the magnitude of the micromirror edge diffraction transmitted to any or all output ports, or by appropriate filtering of angular frequencies with a diffraction grating used to separate a multi-channel optical signal into constituent spectral beams.

The invention discloses a current type wireless power supply system load self-adapting control method. The method comprises steps of measuring the current value Idc of a direct current power supply of a current type wireless power supply system; calculating the load value RL of a load circuit in accordance with the current value Idc of the direct current power supply; calculating a minimum angle frequency value omega meeting the preset transmission efficiency eta in accordance with the load value RL of the load circuit; and adjusting a variable component of a primary side resonant network, and enabling the resonance angular frequency omega 0 of the primary side resonant network to be equal to omega. The method the advantages that a wireless communication module is not used, the design cost is low, only a parameter is measured, the detection error is little, the accuracy is high, the circuit design is simple, the implementation is easy, the system determines the variation condition of the load circuit in accordance with the real-time detected current value of the direct current power supply, the parameter of the primary side resonant network is changed in accordance with the change of the load circuit, the working efficiency of the system is improved and the system has high working efficiency when the load is changed dynamically.

The present invention provides a space rotating magnetic field generating device of random rotating axle, the coil part (2) is three groups pairwise orthogonal Helmholtz coils, every group coil is made up of three groups winding Helmholtz coils, and three groups coil connect each phase of three-phase current respectively. According to parameter of rotating magnetic field (1) required by user, rotating axle direction angle Theta, Phi determines initial position of rotating magnetic field Gamma, angular frequency of rotating magnetic field Omega and amplitude of rotating magnetic field B0, CPU (311) obtains variation magnetic field produced by three groups coils: BX,BYand BZ, and obtains impulse width and frequency of corresponding modulating signal, three groups waveform generators (312) of control power source part (3) inversion produce three groups three-phase current, supply for three groups coils, and produces three direction variation magnetic field. The required rotating magnetic field (1) is obtained after the three variation magnetic fields are overlapped in space. Impulse width and frequency of every waveform generator (312) modulating signal can be adjusted for changing rotating axle of rotating magnetic field, amplitude, frequency and initial position.

A plasma device which is provided with a container, a gas supply system, and an exhaust system. The container is composed of a first dielectric plate made of a material capable of transmitting microwaves. An antenna for radiating microwaves is located on the outside of the container, and an electrode for holding an object to be treated is located inside the container. The microwave radiating surface of the antenna and the surface of the object to be treated with plasma are positioned in parallel and opposite to each other. A wall section of the container other than that constituting the first dielectric plate is composed of a member of a material having electrical conductivity higher than that of aluminum, or the internal surface of the wall section is covered with the member. The thickness (d) of the member is larger that (2 / μ0σ)1 / 2, where σ, μ0 and ω respectively represent the electrical conductivity of the member, the permeability of vacuum and the angular frequency of the microwaves radiated from the antenna.

The invention relates to an online identification method on the rotor resistance of an asynchronous motor, and the method is used for optimizing resistance parameters in the vector control with a speed transducer. The invention includes the following procedures of collecting the electromagnetic torque Te and the psi 2parameter of the flux linkage of a rotor, identifying the rotor resistance according to the electromagnetic torque Te and the psi 2 parameter of the flux linkage of the rotor by the formula that r2 is equals to 3 / 2Pn omegas psi <2>2 / Te, among which the p n is the number of the pole-pair of the motor, and the omega s is the slip angular frequency, taking the identified rotor resistance as the parameter to implement the vector control of the motor. The online identification method of the invention can identify the rotor resistance of the asynchronous motor on line on the vector control of the motor with the speed transducer by a voltage model method, thereby being simple and practical, and having higher precision. The invention can identify the resistance parameter of the rotor on line accurately under any condition that load exists, and the resistance parameter is stable. Experiments prove that the invention can obtain right resistance parameter of the motor rotor accurately whether the motor is in cold state or in hot state.

The invention discloses a method for measuring the electrical conductivity of solution, comprising the following steps of: exciting electrodes by adopting a sinusoidal signal with stable voltage amplitude and fixed frequency; carrying out two-channel high-speed A / D transformation on an excitation voltage signal and a current signal of electrode response at the same time; computing voltage effective value U, current effective value I and active power P; dividing the current effective value I by the voltage effective value U to obtain an apparent resistance m, computing a power factor cosine theta and tangent absolute value n of a power factor angle theta, and computing the resistance value Rx between the electrodes by utilizing the following formula, wherein the omega in the formula is angular frequency of the excitation signal and Cp expresses the sum of distributed capacitances between the electrodes and electrode leads; and obtaining the electrical conductivity by utilizing the formula G=K / Rx, wherein the K is an electrode constant. By adopting the invention, adverse effects of electrode polarization, electrode interelectrode and electrode lead distributed capacitances to the measurement of electrical conductivity of the solution can be completely eliminated, and the electrical conductivity of the solution can accurately measured.

The invention discloses a method for determining an initial position angle of a rotor of a permanent-magnetic synchronous motor. The method comprises the steps of: inputting a high-frequency rotary voltage vector signal with an amplitude value as U, an angular frequency as omega and an initial phase position as thetaci to obtain an alpha-axis current ialpha and a beta-axis current ibeta; converting the ialpha and the ibeta into a coordinate which rotates synchronously for the angular frequency omega to obtain a d-axis current id and a q-axis iq; performing low-pass filtering on the id and iq to obtain Idf and Iqf; calculating a predicted value thetari of the initial position angle of the rotor by utilizing a formula; inputting a pulse voltage vector in the stator winding, wherein the angle is equal to thetari; obtaining the d-axis current and an integral under the action of the pulse voltage vector, thereby obtaining sigmaI0; after 3 ms-10 ms, inputting another pulse voltage vector to the stator winding, wherein the angle is equal to thetari plus 180 degrees; obtaining the d-axis current and an integral under the action of the other pulse voltage vector, thereby obtaining sigmaIpi; and comparing the absolute values of the sigmaI0 and the sigmaIpi, wherein if the absolute value of the sigmaIpi is greater than the absolute value of the sigmaIpi, the initial position angle of the rotor is equal to thetari; otherwise, the initial position angle of the rotor is equal to thetari plus 180 degrees. The method for determining the initial position angle of the rotor of the permanent-magnetic synchronous motor, disclosed by the invention, has the advantages of simple treatment process and high detection precision.

The invention relates to a microporous membrane. The membrane can have an average thickness of 23 ?m or more, an air permeability in a range of about 20 sec / 100 cm3 to 100 sec / 100 cm3, a pin puncture strength of 2,450 mN or more, and a heat shrinkage ratio of 12% or less at 105° C. The membrane can be produced from a polyolefin solution made by combining a membrane-forming solvent and at least one polyolefin resin containing polyethylene having a viscoelastic angular frequency ??0#191 of at least about 0.01 rad / sec.

In an apparatus for detecting a distance and improving the SN ratio of received signals, an angular frequency (ω1) of sinusoidal wave signals generated by a sinusoidal wave generator is brought into synchronism with an angular frequency (ω) of burst pulse signals, and signals received by a transmitter / receiver microphone are orthogonally demodulated by using sinusoidal wave signals of the synchronized angular frequency. A microcomputer adds up the vectors of the demodulated signals for only a period of time equal to a section of transmitting the transmission waves from the transmitter / receiver microphone. A distance to a body is detected by using the received signals of which the vectors are added up.

A shaker movement permits an arbitrary path of motion in a shaker's shaking action. The shaker movement comprises independent control over the "X" and "Y" directions of the shaking actions by a pair of track assemblies, each track assembly comprising a pair of fixed rods and a pair of sliding rods that are interconnected with each other in a rectangular, grid-like pattern. Motion in both directions can be driven by a single motor utilizing independent pulley-and-belt systems or by two synchronized motors which are connected to a sliding rod of each track assembly. By altering the relative amplitude, phase angle, and frequency between the "X" and "Y" directions, the shaking action can follow a desired path. The shaker path can be varied from the traditional circular orbital motion or linear motion, to a new group of shaking patterns in which the direction of the shaking movement can reverse. The new patterns of shaker movement cause the liquid being shaken to be more thoroughly mixed, with less power input, and at a lower angular frequency than is practical with traditional paths of motion. This results in higher rates of gas transfer to and from the liquid, resulting in greater growth of a bacterial culture, and for higher rates of mass transfer at equivalent levels of energy input.

The present general inventive concept relates to apparatuses and / or methods for measuring an in-phase and quadrature (IQ) imbalance. In one embodiment, a detector can measure an error caused by an IQ imbalance using a first IQ signal including a desired signal and a corresponding image signal by the IQ imbalance. The detector can include a derotator to derotate the first IQ signal by a first angular frequency to obtain a second IQ signal and derotate the first IQ signal by a second angular frequency to obtain a third IQ signal, a DC estimator to obtain a fourth IQ signal corresponding to a DC component of the second IQ signal and a fifth IQ signal corresponding to a DC component of the third IQ signal and a controller can determine a gain error or a phase error from the fourth IQ signal and the fifth IQ signal.

A method of generating a single photon, includes preparing an optical resonator including a resonator mode of a resonance angular frequency ωc, preparing a material contained in the optical resonator, including a low energy state |g> and a high energy state |e>, and including a transition angular frequency ωa between |g>−|e> that is varied by an external field, applying, to the material, light of an angular frequency ωl different from the resonance angular frequency ωc, and applying a first external field to the material to vary the transition angular frequency ωa to resonate with the angular frequency ωl, such that a state of the material is changed to |e>, and then applying a second external field to the material to vary the transition angular frequency ωa to resonate with the resonance angular frequency ωc, such that the state of the material is restored to |g>.

A control apparatus for an induction motor is provided and includes a rotating-speed locked loop and a feed-forward magnetizing-axis angular position emulator. The rotating-speed locked loop emulates a speed control loop of the induction motor for producing an emulated torque current and an emulated rotor angular speed. The feed-forward magnetizing-axis angular position emulator receives the emulated torque current and the emulated rotor angular speed for producing a feed-forward estimated magnetizing-axis angular position, wherein according to the feed-forward estimated magnetizing-axis angular position, a first voltage controlling the induction motor is transformed from a synchronous reference coordinate system of the induction motor to a static reference coordinate system of the induction motor, and a two-phase current detected from the induction motor is transformed from the static reference coordinate system to the synchronous reference coordinate system. The state the stator angular frequency is at zero can be skipped through the apparatus.

The invention provides an inverse Q filtering method for a seismic wave signal. The method comprises the following steps: extracting a quality factor Q value from the seismic wave signal collected from a seismic channel; performing time-frequency transformation on the collected seismic wave signal so as to acquire a seismic wave frequency spectrum shown in the specification, wherein tau is a travel-time and omega is an angular frequency; and performing inverse Q filtering on the seismic wave frequency spectrum by utilizing the following formula shown in the specification, so as to acquire the seismic wave frequency spectrum U (tau, omega) after inverse Q filtering, wherein gamma is equal to 1 / (phiQ); omega h is the highest frequency within the seismic bandwidth; sigma 2 is a stable factor; i is an imaginary part unit; tau' in exponential terms is an integration variable, and the value range of the integration variable is within an integrating range from omicron to tau; and the quality factor Q is related to the integration variable tau'. The high-frequency component is not pressed in the stabilizing treatment process in the inverse Q filtering method provided by the invention, so the inverse Q filtering method has the advantages that the resolution ratio is increased but the high-frequency noise is not increased, and the signal to noise ratio (SNR) is increased.

The invention discloses a three-phase alternating current phase sequence detecting device and a method thereof. The detecting device comprises a three-phase alternating current sampling module, a coordinate system transformation module, an angular frequency signal acquirement module and a phase sequence direction judgment module. The detecting device includes the following detecting method: A. the three-phase alternating current sampling module samples the instantaneous values of current three-phase alternating current to obtain a sampling instantaneous value; B. the coordinate system transformation module converts the sampling instantaneous value into a two-phase synchronous rotating coordinate system from a three-phase static coordinate system, and q axis component xq can be worked out; C. the angular frequency signal acquirement module receives xq and obtains an error signal; the error signal can be adjusted to change the value of the xq; the acquired value of the angular frequency Omega 0 can be output to a feedback channel module thereof and the phase sequence direction judgment module; the feedback channel module outputs Omega 0 to the coordinate system transformation module; D. the phase sequence direction judgment module distinguishes the mark of Omega 0 and determines the phase sequence direction. The device provided by the invention can detect the real-time condition of the phase sequence. The device provided by the invention is simple and practical and has excellent capacity of resisting disturbance.

A micro power grid frequency control method and a system are provided, wherein the method comprises the steps of obtaining d-axis and q-axis components of an output voltage, an output current and a filtering inductance current of an LC filter at the grid side of an inversion power supply; obtaining the output reactive power, the output active power and an output voltage amplitude of the LC filter in combination with the d-axis and the q-axis components of the output voltage and the output current; obtaining a virtual excitation electromotive force by taking the output reactive power and the output voltage amplitude as the input of a virtual excitation controller; obtaining an active power increment by inputting an output angular frequency of a virtual synchronous generator controller into a frequency controller; and obtaining a d-axis and a q-axis reference instruction value and an output angular frequency of the inverter output voltage by taking the output active power, the virtual excitation electromotive force, the active power increment and the d-axis component and the q-axis component of the filtering inductance current as the input of the virtual synchronous generator controller. According to the invention, the micro power grid frequency change caused by load disturbance can be effectively inhibited; and the island micro power grid can be operated stably.