8 results about "Field frequency" patented technology

The invention discloses a strong dispersion dielectric grating guided mode resonance optical filter insensitive to angles. The filter is based on a strong-dispersion sub-wavelength dielectric grating structure, and the resonant wavelength shows the characteristic of being insensitive to the change of an incident angle. By reducing the thickness of the grating layer and the grating line width, the angle sensitivity of the device can be further reduced. The insensitivity of the wavelength of the device to the angle mainly depends on the intrinsic dispersion characteristic of an excited optical mode in the device, that is, the frequency of the optical mode with strong dispersion changes slowly along with in-plane wave vectors, so that the change of the far-field frequency response along with the angle is obviously slowed down. Based on the principle, an angle-insensitive metasurface device can be designed by using a strong dispersion optical mode. The design method provided by the invention is not only suitable for an optical filter, but also can be popularized to other metasurface devices with strict requirements on angle sensitivity, and has wide application prospects in the fields of optical communication, hyperspectral and multispectral imaging, sensing and the like.

The invention discloses a new energy unit-station level frequency modulation parameter measurement and identification method based on frequency response analysis, and the method comprises the steps: enabling an obtained model to give consideration to the frequency modulation control precision and the adaptability to a plurality of operation conditions through constructing a closed-loop design of offline modeling-online correction-regular updating; a systematic technical path is provided for improving the frequency modulation performance of a new energy station, so that the frequency safety of a novel power system is guaranteed; comprising the following steps: off-line constructing a frequency modulation model of a first-layer unit level of a new energy station through principle analysis; constructing a second-layer station-level frequency modulation coordination control model of the new energy station; establishing a multi-dimensional frequency response deviation quantitative index system; designing a frequency modulation parameter correction optimization model in combination with measurement data of a field frequency test or an online frequency response event to obtain online measurement and discrimination parameters of the new energy unit-field station level frequency modulation model; and a regular updating mechanism is established, and frequency modulation parameters are re-identified and corrected.

The utility model discloses an embedded loop type RFID tag, and relates to the technical field of RFID tags. Comprising an antenna and a chip, and the chip is connected above the antenna through a conductive adhesive; the antenna is in a sheet shape, an opening is formed in the middle of the antenna, a connecting arm is arranged in the opening, a binding area is arranged in the middle of the connecting arm, and the binding area is used for being connected with a chip; a loop loop area is formed in the opening and located on the inner side of the connecting arm, and a radiation area is formed on the antenna and located on the outer side of the loop loop area. According to the utility model, during working, the tag antenna innovatively adopts a loop loop area embedded antenna design and a loop loop area overall embedded design, and the loop loop area is provided with different embedded depths, so that the far and near field frequency point adjustment and performance optimization of the tag can be realized.

A method for starting an EC motor having a stator and a rotor, comprising the steps of determining a first position of the rotor when the rotor is stationary by means of discrete signal injection, accelerating the rotor by means of a controlled rotating field, determining a speed of the rotor on the basis of a back EMF after reaching a predetermined rotating field frequency, comparing the speed determined, with a first predetermined speed value, and, if the speed determined is greater than the first predetermined speed value, determining a second position of the rotor on the basis of the back EMF and changing to a closed-loop operation on the basis of the back EMF.

A method of starting an EC motor comprising a stator and a rotor, comprising the steps of: a) determining a first position of the rotor when the rotor is at rest (101) by discrete signal injection; b) achieving acceleration of the rotor (103) by a controlled rotating field; c) determining a rotational speed of the rotor based on a back electromotive force after a predetermined rotating field frequency is reached in step b) (105); d) comparing the rotational speed determined in step c) to a first predetermined rotational speed value (107); and e) if the rotational speed determined in step c) is greater than the first predetermined rotational speed value: determining a second position of the rotor based on the back electromotive force, and switching to a closed loop operating mode based on the back electromotive force (109).

This invention discloses a method, system, and device for early warning of operational risks in information systems, specifically relating to the field of operational security and risk early warning technology. The method includes the following steps: collecting user data to generate an operation log correlation index; generating a data transmission integrity coefficient based on the operation log correlation index; generating a multi-source data correlation matrix based on the integrity coefficient; generating a multi-dimensional abnormal correlation threshold based on the multi-source data correlation matrix; and generating an operational risk warning level and handling suggestions based on the multi-dimensional abnormal correlation threshold. This invention improves the effectiveness of early warning for operational risks in information systems through multi-stage data processing, multi-technology integration, and multi-dimensional analysis. It collects and cleans user operation behavior data, combines a baseline log template with precise time windows to statistically analyze field frequencies, and improves the accuracy of the operation log correlation index, laying a reliable data foundation for subsequent analysis.

The invention discloses a method for determining transmit-receive distance based on detection depth of a controllable source audio magnetotelluric method, and the method comprises the steps: carrying out the simulation calculation of an electromagnetic field of a uniform geodetic model through employing a fast Hankel transformation method, mainly calculating the Cannius apparent resistivity and impedance phase under the conditions of different transmit-receive distances and different geodetic resistivity; determining the lowest far-field frequency, and concluding a formula for calculating the lowest far-field frequency by using a field source condition; and a detection depth calculation formula is further deduced according to the formula. Verifying the correctness of the calculation formula of the lowest far-field frequency and the calculation formula of the detection depth by using a field test mode, determining the lowest far-field frequency of the actually measured data and the corresponding apparent resistivity, calculating the actually measured detection depth, and comparing the actually measured detection depth with a theoretical value calculated by using a formula derived by induction; in order to conveniently judge the lowest far-field frequency in the CSAMT data, AMT data is also collected for comparison.

The application discloses a kind of turbulent flow adaptive steel casing intelligent leveling hoisting multi-modal control method and system, the method includes: in steel casing hoisting operation area, multiple-source sensor is laid out, and the original signal of each sensor is collected in real time, the observation of each sensor is obtained by normalizing the original signal, according to the preset multi-modal perception fusion function, the observation of each sensor is fused into fusion perception field;The corresponding frequency domain field is obtained by Fourier transform to fusion perception field, and the probability of frequency domain field frequency energy in each spectral energy box is calculated to calculate local spectral entropy, according to frequency domain field and local spectral entropy, turbulent flow adaptive frequency spectrum is calculated;The current attitude error vector of steel casing is mapped to by mapping operator through turbulent flow adaptive frequency spectrum, and according to target leveling attitude vector, tracking weight matrix and energy consumption balance penalty term, control vector is solved, and leveling instruction of each lifting point is generated by anti-normalization to control vector.