Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2024-02-07 Cooperative journals: 《应用力学学报》
Abstract:
The vibro-impact process is simplified by the instantaneous impact model,but the classical Newton’s restitution coefficient model adopted brings errors in the calculation.In this paper,a modified restitution coefficient model is introduced to replace the classical Newton’s model of restitution coefficient,and the stochastic response of a class of vibro-impact systems with bilateral barriers under broad-band noise excitation is investigated.Based on the energy levels of the system,its motion can be categorized into two types:non-colliding vibration and bilateral collision vibration.Subsequently,the average drift and diffusion coefficients for these two types of motion are determined using the energy envelope random averaging method.On this basis,the corresponding Fokker-Planck-Kolmogorov(FPK)equation is established and solved,leading to the steady-state response of the system.For illustration,the proposed method is applied to the Duffing oscillator.The effects of the yield velocity,interval and the noise excitations on the PDFs of stationary responses are examined,and the validation of analytical results is verified by the Monte Carlo simulation data.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2024-02-07 Cooperative journals: 《应用力学学报》
Abstract:
The marine towed system is a typical rigid-flexible multi-body system.It should be pointed out that up to now,the damping effect on dynamics of marine towed cable system has not been fully considered in most of the studies.However,in the structural dynamic analysis of marine towed system,especially in the dynamic response analysis of towed cable rotation process,the damping effect cannot be ignored.The modal characteristics of the cables are also highly complex due to damping.In order to study the influence of Rayleigh damping on the rotation process of towed cable,with the basis of the lumped mass method,the expression form of Rayleigh damping in towed cable system is further sorted and decomposed,and the influence of each damping component is summarized.Some general conclusions are obtained,which have certain guiding significance for actual towing operation at sea.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2024-02-07 Cooperative journals: 《应用力学学报》
Abstract: The on-orbit deployment of the spatial structure involves the complex high-dimensional nonlinear dynamic problems,the analysis on which is one of the challenges in the astrodynamics field and the precondition of performing the control strategy on the on-orbit deployment process.In this paper,taking the 1st deploying stage of the IKAROS solar sail as an example,the flexible stretching hub-beam model is proposed and the dynamic equation for which is presented based on the Hamiltonian variational principle.Employing the complex structure-preserving method which focuses on the local dynamic behaviors of the system,the 1st deploying process of the IKAROS solar sail is simulated under two working conditions(invariable torque and constant power)respectively.The numerical results show that the differences between the rotational velocities of the hub for the two cases are remarkable.The rotational stability of the hub turns bad with the invariable torque,which results in the large work needed in the 1st deploying stage of the IKAROS solar sail and implies that the constant power working condition can save energy in this process.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2024-02-07 Cooperative journals: 《应用力学学报》
Abstract:
This paper introduces a cable damage identification method for cable-stayed bridges based on principal component analysis(PCA)to facilitate efficient cable damage detection.The proposed approach involves collecting the acceleration response of the cable structure when subjected to a moving load.Subsequently,the PCA method is employed to reduce the dimensionality of the time-domain signal.Statistical data are then extracted from the reduced dimension signal,and a multi-order statistical moment fusion index is constructed using the Dempster-Shafer(D-S)evidence theory for identification purposes.Using the Yonghe Bridge in Tianjin as a case study,the paper explores the impact of cable damage degree,load mass,and load moving speed on damage identification accuracy through finite element numerical simulations.The analysis results demonstrate the efficacy of the proposed method,highlighting its robust recognition capabilities and resilience to noise.The developed approach proves to be a promising tool for accurate and timely identification of cable damage in cable-stayed bridges,contributing to enhanced structural safety and maintenance practices.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2022-11-17 Cooperative journals: 《Electrical & Electronic Engineering Research》
Abstract: This article is fully combed the related literature, the application of big data in the archive management innovation with a thorough system of literature analysis, and obtained from file data acquisition, data transmission, data storage, data archives utilization, staff training and safety archives construction aspects of the need to create a file management system based on big data applications. And Finally, this article analyzes the archival management innovation practice and its effect based on big data application in China, and draws the corresponding value conclusion.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2022-11-17 Cooperative journals: 《Electrical & Electronic Engineering Research》
Abstract: In order to improve the quality of photovoltaic power injected into the grid, a high-voltage flexible direct current (Voltage Source Converter-High Voltage Direct Curren, VSC-HVDC) grid-connected scheme based on a micro-synchronous phasor measurement unit (μPMU) coordinated control strategy is proposed. The four-terminal topology of photovoltaic power plants connected to the grid via VSC-HVDC is designed, and two photovoltaic power plants are connected to the grid via VSC-HVDC model using Matlab/Simulink simulation software to simulate when the light intensity is changed, the photovoltaic power plant is out of operation and the grid voltage occurs In the case of sudden changes, the system voltage, power, and AC side frequency can still maintain stable operation, which verifies the feasibility and effectiveness of the transmission scheme, and improves the stability and power quality of the power grid.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2022-11-17 Cooperative journals: 《Electrical & Electronic Engineering Research》
Abstract:
In order to improve the convergence of multi-objective differential evolution (DEMO) algorithm while ensuring well distribution, a new method of center mutation-based DEMO (CM-DEMO) is proposed. Firstly, the form of mutation is improved, the center of the population in the current generation is taken as a base vector, and then the direction of difference vector is determined according to the fitness value of the three random vectors of individuals, secondly, the strategy of adaptive crossover probability is given, the crossover probability is determined according to the distribution of fitness value in the population. Test of benchmark functions show that CM-DEMO algorithm has faster convergence rate. Finally, CM-DEMO is applied to environmental economic dispatch of power system. Compared with other methods, the simulation results obtained demonstrate the feasibility and effectiveness of the proposed algorithm for solving the problem.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2022-11-17 Cooperative journals: 《Electrical & Electronic Engineering Research》
Abstract: In oil and gas exploration and mineral resource exploration, rock sample identification plays an immeasurable role due to its strong operability. Besides the methods of identifying rock samples by gravity, magnetism, remote sensing, electromagnetics, etc. a new way is to establish an automatic identification and classification model of rock samples by using image deep learning methods. This paper uses the transfer learning method to build a deep convolutional neural network model to realize the automatic classification and recognition of rock samples. First, the original data is preprocessed to ensure that it can be better used for model training. Then, based on the deep learning tool framework TensorFlow, this article uses the transfer learning method to migrate the Inception-V3 deep convolutional neural network model. To be trained in the preprocessed target data set, and improve the learning effect of the target task, so that more reasonable image features can be extracted, until it is trained into a neural network model in the target field, and the rock sample can be better classified.
Subjects: Dynamic and Electric Engineering >> Other Disciplines of Dynamic and Electric Engineering submitted time 2022-11-16 Cooperative journals: 《Electrical & Electronic Engineering Research》
Abstract:
It is obvious that the modern agriculture needs the support of modern finance. The agricultural credit guarantee system, is an important means to promote the financial capital into the agriculture industry, and to solve its financing difficulties and its high cost. The designing and application of agricultural guarantee digital system platform will not only be beneficial to accelerate transformation and promotion of the mode of agricultural development, but also be positive significance on the steady growth, promoting the reform, restructuring and livelihood. This paper summarizes the relevant literatures on agricultural guarantee system, designs and develops a set of agricultural guarantee digital system platform based on the application of blockchain and big data technology, and finds it achieves a lot of benefits and good effects based on the practice in China.