Terms Of Dynamic Analysis Research Articles

Static and Dynamic Analysis of Coupled Vibration of Suspension Bridge Structure Under Earthquake Action

This article investigates the coupled vibration problem of suspension bridge structures under earthquake action, and conducts static and dynamic analysis using computer algorithms. In terms of static analysis, complex structures are divided into many small elements, and the stress and deformation of each element are calculated through finite element analysis, thereby obtaining the static characteristics of the entire structure. In terms of dynamic analysis, the seismic response analysis method based on time history considers seismic action as a time-varying external excitation, and calculates and simulates the dynamic response of the suspension bridge structure. In order to achieve efficient and accurate calculations, this article also adopts optimization algorithms and numerical calculation methods. Through a comprehensive study of statics and dynamics analysis, the key characteristics and regularities of coupled vibration of suspension bridge structures under earthquake action have been obtained. These research results not only provide important theoretical guidance and technical support for related engineering practices, but also provide useful references and inspirations for dynamic analysis and optimization design of similar structures. Meanwhile, using computer algorithms and simulation software for static and dynamic analysis can significantly reduce analysis costs and time, improve analysis accuracy and efficiency, and have broad application prospects.

Analysis of regional differences in green energy efficiency in countries along “the Belt and Road” Initiative zone—Based on super efficiency DEA model and Malmquist index method

This study uses the super-efficiency DEA model and Malmquist index analysis to evaluate the green energy efficiency of 58 countries along “the Belt and Road” Initiative zone from 2012 to 2021 and uses Tobit regression to analyze the external environmental influences on their green energy efficiency. The results of the study show that in the static analysis, The overall green energy efficiency of 58 countries along the “the Belt and Road” initiative area is low, and there are obvious regional differences; In terms of dynamic analysis, the Malmquist Index shows a slight fluctuation trend from 2012 to 2021. Tobit regression models show that external factors such as economic strength, energy consumption structure, industrial structure, and R&D expenditure are significantly and positively related to green energy efficiency. Based on this, this study proposed that countries should make good use of their resource advantages to improve the overall green energy efficiency of “the Belt and Road” Initiative zone according to local characteristics; strengthen inter-regional cooperation and exchange among countries, and implement outbound strategies to create a favorable development environment for green energy efficiency in “the Belt and Road” Initiative zone. Create a favorable development environment for green energy efficiency in “the Belt and Road” Initiative region.

Estimating the Long-Run Determinant of the Efficiency of the Stock Market in India

One of the prominent views is that development in a stock market has a positive impact on economic growth. The role of the stock market becomes important as it leads to capital formation in an economy which is used for producing goods and services in it, leading to growth in the real sector. However, it is only possible if the stock market is efficient enough to mobilise saving from a deficit spender unit to a surplus spender unit. Therefore, our study proposes to estimate the determinant of stock efficiency with the help of a fully modified ordinary least-squares model. The result of the analysis indicates that although both the risk-free interest rate and market capitalisation have a positive and significant impact on stock return, the impact of market capitalisation is larger. In terms of dynamic analysis, the error correction model shows that the speed of adjustment is around 50 per cent or time taken for re-establishing the long-run equilibrium is about two years. As market capitalisation is one of the important determinants of the efficiency of a stock market, the government should bring new reforms in the capital and money markets so that new financial innovations can be introduced in the market. Simultaneously, the regulation should be made to provide higher protection to the investor which further helps them to increase their confidence in the market.

Random fatigue. A new frequency domain criterion for the damage evaluation of mechanical components

The evaluation of the fatigue behavior of mechanical systems and components subjected to random loads is increasingly being addressed to the frequency domain environment both in terms of dynamic analysis and in terms of results post-processing.The procedure set out in the paper (bands method) is formulated without assumptions about the shape of the Power Spectral Density (PSD) function to be analyzed, in order to obtain a criterion that can be applied to any typology of the related random process. The basic idea of the proposed approach is that each PSD function can be divided into frequency bands, for each of them a Rayleigh distribution could be associated and that the aforementioned distributions could be opportunely combined to obtain the actual damage. The method is theoretically developed and numerically validated on a particular subset of PSD functions by comparing the results obtained with those carried out by the time domain damage evaluation reference method and a frequency domain direct approach (Dirlik’s method).With regard to the time domain reference criterion the stress time histories are generated by the indirect method (a previously defined authors’ method), the cycles spectra are obtained by Rain Flow Counting, (RFC) and the damage is evaluated by Palmgren–Miner’s rule.

Synthesis of Constructive-Functional Parameters to Improving the Dynamic Behavior of Automatic Mechanisms

Producing of mechanisms for automatic tool (ATCM), for machining centers requires higher performance, in terms of: the reduction of effective time for tool, simplification of kinematic chain, the increasing of reliability and operational safety, the reduction of weight of the entire subassembly, the increasing of positioning accuracy in handling tools. The paper presents how these desiderate can be achieved by improving the dynamic behavior. The objectives of the paper focused on the development of a methodology which allows judicious choice of functional-constructive parameter values, still from the design phase in order to achieve an optimization of the dynamic behavior of mechanisms for automatic tool change. The inclusion of dynamic model for the actuation (hydraulic) in full dynamic model has the advantage that it takes into account real parameters which are involved in the operation of these mechanisms. This paper develops a methodology that allows judicious choice of functional-constructive parameter values, still from the design stage. To obtain a version that is the closest to optimal functioning, in terms of dynamic analysis of the mechanism, the authors propose to develop a method of multi-criteria evaluation on dynamic characteristic parameters. This method ensures the choosing the closest to optimal functioning, in terms of dynamic analysis of mechanism.

Dynamics of magnetic fluid support grinding of Si 3N 4 ceramic balls for ultraprecision bearings and its importance in spherical surface generation

Spherical surface generation mechanism is analyzed using magnetic fluid support grinding of ceramic balls as an example. Grinding experiments of Si 3N 4 ceramic balls were carried out with an emphasis on investigating the effect of dynamic behavior of ball support system on the performance of ball grinding. In the experiment, four different types of supports were used, which are gum sheet/magnetic fluid support, steel sheet/magnetic fluid support, steel sheet/colloid fluid support and steel sheet/air support. It is found that the gum sheet/magnetic fluid support gives the fastest improvement in sphericity during grinding and the best sphericity among the four types of supports. The experimental results were discussed in terms of dynamic analysis, and it was concluded that dynamics of grinding system must be taken into consideration in order to understand comprehensively the spherical surface generation mechanism.