6 results about "Substitution method" patented technology

The present application relates to a kind of resource optimization method based on RIS auxiliary wireless energy-carrying backscattering communication system, belong to low-power Internet of Things technical field, the present application is aimed at the problem that transmission performance is poor caused by obstruction obstruction and channel perturbation, consider transmission time constraint, energy collection constraint, the maximum interference power constraint allowed by main receiver, channel uncertainty constraint and intelligent metasurface phase shift constraint, construct energy efficiency maximization resource management model based on bounded channel uncertainty, utilize worst criterion method and Cauchy inequality to convert original non-convex optimization problem containing parameter uncertainty into deterministic problem;By variable substitution method, continuous convex approximation method, block coordinate descent method and semi-positive definite programming method, the deterministic problem is converted into convex problem solution, the present application can effectively improve system total energy efficiency, while reducing main user interruption probability, improve signal propagation path.

The invention discloses a double-station RCS (radar cross section) scaling test system and a test method for an electrically large-size target in an indoor compact range. The system comprises a transmitting feed source, a receiving feed source, a transmitting compact range parabolic reflecting surface, a receiving compact range parabolic reflecting surface, a transmitting compact range movable bracket, a receiving compact range movable bracket, a target to be measured, a target placement turntable, a vector network analyzer, a three-port power divider and a control and data processing center, the to-be-measured target comprises two types: one type is a calibration body, and the other type is a scaling target model; and calculating and processing to obtain an RCS value of the scaled target model through a known RCS of the calibration body, a receiving feed source output intermediate frequency signal obtained by measurement of the calibration body and a receiving feed source output intermediate frequency signal obtained by measurement of the scaled target model by utilizing a substitution method. The system is simple in structure and convenient to install, and the testing efficiency is improved.

The invention relates to the technical field of acoustic engineering, in particular to an equivalent substitution method and system for sound propagation analysis of a volume sound source in a complex sound field environment. The method comprises the following steps: establishing a finite element model of a volume sound source containing complex boundary conditions by utilizing engineering software, carrying out truncation processing on a computational domain, and calculating and obtaining sound pressure and normal vibration velocity on a closed integral surface surrounding the volume sound source; based on the sound pressure and the normal vibration velocity, performing external sound field solution on the closed integral surface by adopting a free field sound radiation integral mode to obtain sound pressure distribution on at least two layers of enveloping surfaces located on the outer side of the volume sound source; arranging a plurality of equivalent point sound sources in the volume sound source, constructing an equivalent source solution equation by taking the sound pressure on at least two layers of envelope surfaces as a matching target, and calculating the source intensity of each equivalent point sound source; and based on the positions of the equivalent point sound sources and the corresponding source intensities of the equivalent point sound sources, accumulative calculation of the volume sound sources in a complex sound field environment is realized by adopting a channel propagation method based on the point sound sources, so that propagation analysis is carried out.

The invention provides a system and a method for calibrating dynamic characteristics of a microphone based on a substitution method principle, and relates to the technical field of detection sensing. Based on a substitution method principle, a digital closed-loop control sound horn traveling wave tube calibration device is established, and sound attenuation of sound wave conduits with different lengths under a full frequency band is obtained through a system full frequency band dynamic calibration method, so that a measurement result of a monitoring system can be corrected. In the field of aero-engine acoustic microphones, within an allowable error range, a measurement result of a noise measurement monitoring system can be corrected, that is, the correction amount and a value measured in an experiment are added to obtain a final correction value, the test precision is improved, and the test cost is reduced. The method provides more accurate data for subsequent exploration of the relationship between the sound pressure and other physical quantities, and is suitable for the condition that a standard microphone cannot be obtained due to condition limitation.

The application discloses the technical field of integrated energy system operation and planning, and relates to a kind of energy system multi-energy flow calculation method, device and storage medium based on topological partition, method includes: to the each subsystem of pre-constructed IES mathematical model is topologically partitioned, each subsystem is decomposed into only containing radial subnetwork topology or ring subnetwork topology minimum sub-block;Determine the connecting node of adjacent sub-block and aggregate to form equivalent topology;Each described sub-block is set to balance node, with balance node as reference, based on the subnetwork topology type of equivalent topology, radial subnetwork topology adopts forward-back substitution method to solve sub-block multi-energy flow, and ring subnetwork topology adopts finite element method to solve sub-block multi-energy flow;Based on the state quantity of the connecting node, the calculation results of each sub-block are mapped to original IES topology according to preset rule, and multi-energy flow calculation result is output.The application can alleviate the technical problems that existing technology cannot meet the calculation requirements of complex mixed topology IES.

The application provides a two-stage distribution robust line loss optimization method considering wind and light uncertainty, and belongs to the technical field of new energy sources. First, a day-ahead-real-time two-stage line loss optimization method is constructed. In the day-ahead stage, a multi-scenario sample set capable of reflecting wind and light output uncertainty is generated by combining a K-means clustering algorithm and a conditional generative adversarial network. In the real-time stage, based on the day-ahead optimization result and updated output information, a multi-scenario distribution robust optimization model is used to realize joint correction of line loss and economic dispatch. In the optimization solving process, a forward-backward substitution method is embedded into a power flow calculation model to accurately reflect line transmission loss of the distribution network in the transformer area. Secondly, a distribution robust optimization method based on scenario generation is constructed. A diversified scenario set is generated by using historical wind and light data through K-means clustering and a conditional generative adversarial network, and distribution robust optimization planning and correction are carried out under different scenarios.