9results about How to "Reduce the sampling frequency" patented technology

The invention relates to the field of water quality evaluation, in particular to a rain source type river water quality evaluation method and system.The method comprises the steps that a sensor of a water quality monitoring system monitors micro-rain detection data of a micro-rain event, and the water quality monitoring system adjusts the sampling frequency of the sensor through an adaptive algorithm; obtaining water quality monitoring data through a micro-pollution mutation detection method; constructing a water quality recovery model of the micro-rain event through nonlinear kinetic analysis, and predicting a peak value and recovery time of water quality change of the micro-rain event; identifying a significant sudden change point of water quality change through a chaos theory algorithm, and adjusting the sampling frequency of the sensor through fuzzy logic control; key pollutants are obtained according to the peak value of the water quality change and the recovery time, and the key pollutants and pollution source data are subjected to data correlation analysis to judge the pollution source. The problems that the impact and the influence of a micro-rain event on the river water quality are not fully considered, so that the water quality evaluation is not timely and accurate enough, and the water quality change cannot be effectively captured and a pollution source cannot be analyzed are solved.

The invention relates to the technical field of power system detection and protection, and discloses a ground fault detection and protection method, system and device. The method comprises the following steps: according to a sampling frequency fT, respectively collecting currents of a head end and a tail end of the DC filter to obtain a head end current sequence and a tail end current sequence; according to the head end current sequence and the tail end current sequence, an absolute value obtained by differencing the head end current and the tail end current collected at the same moment is divided by a set coefficient C to obtain a point-line distance D; according to the time window length T, accumulating the point-line distances D calculated by the corresponding head end current and tail end current to obtain the sum Ds of the point-line distances; and determining the fault type according to the sum Ds of the point-line distances and the setting value Dset. According to the method, the fault of the power transmission line can be monitored in real time by collecting the currents at the head end and the tail end of the direct current filter, when the fault occurs, the currents at the head end and the tail end of the direct current filter synchronously change, the sum Ds of the point-line distances obtained through calculation is matched and compared with the setting value Dset, and the fault type can be rapidly judged; the efficiency and accuracy of fault type judgment are effectively improved.

The application belongs to the technical field of emergency help equipment, and provides an emergency help signal panoramic projection device, method and terminal, the device can continuously detect the spatial posture and rotating motion state of itself through the environment positioning module, generate corresponding posture data and direction data, the control module can obtain the data and determine the real-time projection pointing angle of the device, and then when the device rotates, the projection control instruction corresponding to the real-time projection pointing angle is generated and sent to the image projection module, so that the image generation unit in the image projection module drives the corresponding rotating transformation of the help image, and the light source in the image projection module irradiates the help image to project the visual help signal which is right and complete. The scheme realizes omnidirectional controllable intelligent projection, can make the help signal cover all directions, at the same time ensures that the projected image can be clearly observed, is more easily identified by the rescuer, reduces the delay caused by signal blur, and improves the probability of being rescued by the help seeker.

The application relates to the field of power system data acquisition and edge computing, and discloses a multi-source heterogeneous data pre-acquisition and edge intelligent processing method, which comprises the following steps: using a modal division mechanism, combining the operation state of power equipment, and performing condition correction on an adaptive sampling frequency to obtain a corrected sampling frequency, so as to acquire multi-source heterogeneous data; extracting fusion core features from multi-dimensional feature vectors; substituting the fusion core features into a general fault judgment model and a time sequence prediction model to respectively output equipment fault prediction results and time sequence prediction results, and obtaining early warning information; based on the fusion core features, the early warning information and the equipment fault prediction results of each acquisition node, and combined with the Lymerzi complexity theory, the spatio-temporal coupling law is identified; and based on the spatio-temporal coupling law and the time sequence prediction results, edge end decision suggestions are provided for source-grid-load-storage collaborative regulation. The application effectively improves the power system data processing efficiency and the power grid operation and maintenance regulation level.

The application discloses a bridge structure self-adaptive sampling monitoring method and device suitable for an extreme road environment, and belongs to the technical field of bridge structure health monitoring.The core target of the application is to solve the problems of repeated arrangement of existing monitoring equipment, road-bridge data fragmentation, and low self-adaptive sampling regulation precision.Through innovative design of a road-bridge multiplexing integrated sensing node, single-node multi-parameter and full-scene monitoring are realized, and the arrangement cost and construction difficulty are reduced; through construction of a self-adaptive sampling strategy based on fuzzy logic control, a feasible algorithm model is given, continuous dynamic regulation of sampling parameters is realized, monitoring precision and low power consumption are taken into account, deep collaborative linkage of road environment monitoring and bridge structure monitoring is realized, and the safe operation of the bridge structure under the extreme road environment is ensured.

The invention discloses a miniaturized Beidou III dual-frequency down-conversion board, comprising a dual-frequency down-conversion module, wherein the dual-frequency down-conversion module is arranged between a low-noise amplifier and a whole mainboard of a receiver, and comprises a feeding circuit, an amplifying circuit, a power dividing circuit, a B3 filtering circuit, a B1c filtering circuit, a frequency conversion processing circuit, and a power conversion circuit. The invention completes the superheterodyne receiving function of Beidou III satellite navigation signals, and provides corresponding intermediate frequency digital signal output, thereby providing intermediate frequency information for Beidou III satellite positioning and navigation solution.

The invention relates to the technical field of power system detection and protection, and discloses a fault detection and protection method, system and device based on a high-voltage direct-current power transmission system. The method comprises the following steps: according to a sampling frequency # imgabs0 #, respectively collecting the current at the head end and the tail end of the DC filter to obtain a head end current sequence and a tail end current sequence; multiplying the head end current and the tail end current collected at the same moment to obtain a judgment sequence; according to the time window length T, determining that the total data number of the judgment sequence in the time window length T is NT and the total point number smaller than 0 is N1, and determining that the percentage of the total point number N1 in the total data number NT is K; and determining the fault type according to the percentage K and the setting value Kset. According to the method, the fault of the power transmission line can be monitored in real time, when the fault occurs, the current synchronization at the head end and the tail end of the direct current filter changes, the fault type can be quickly judged, and the efficiency and the accuracy of judging the fault type are effectively improved.

The present invention discloses a vibration feedback control system of a gantry-type dicing machine, and the present invention relates to the technical field of vibration measurement and control of dicing machines. The vibration feedback control system of the gantry-type dicing machine includes a vibration detection module, a vibration signal processing module, a vibration analysis module, and a vibration control decision generation module. The vibration detection module is composed of sensors arranged at the spindle, the body, and the processing surface of the dicing machine, a signal adjustment unit, and a data acquisition card. The vibration analysis module includes a vibration model and an analysis unit. The present invention realizes the integration of multiple groups of vibration signals, which facilitates the subsequent identification unit to perform overall identification of the correlation coefficient waveforms of multiple vibration sources. Based on the overall identification of a single vibration source, the identification time and identification process are greatly shortened and simplified, and the integration of dicing machine vibration and the shortening of signal data processing time are realized.

The application provides a target detection method based on FMCW-OAM radar target imaging. Since the vortex electromagnetic wave carries the orbital angular momentum OAM, more target information can be provided in radar imaging and target detection. The vortex phase is added in the traditional frequency-modulated continuous wave FMCW radar, the azimuth angle imaging performance of the FMCW radar is improved, the measurement accuracy is not affected by the actual azimuth angle of the target, the distance and the speed of the target, and the azimuth angle detection range is widened. Compared with the pulse OAM radar, the FMCW-OAM radar has the advantages of small short-distance detection blind area, high measurement accuracy, low power consumption and low sampling frequency.