Papers by Keyword: Impact Analysis

Abstract: River play a very important role in regional landscape structure as an ecological element and corridor, and vegetation is very important for the healthy eco-system of a river. The advances of the research and application of near nature river training and vegetation measures were reviewed. The concept, content and function of ecological river training and near natural river training were discussed.. According to the principle of landscape biology, the positive influence of river vegetation on biodiversity was analyzed through edge effects, corridor effects and interference effects. On the basis of in-site experiments of more then ten sample rivers for years, it was concluded that to meet the needs of biodiversity conservation and maintain river ecosystem healthy and steady, in the design and construction of a river, the ecological function should take into due account, proper habitat conditions for plants and plant communities should be created through suitable plan layout, cross section, slope structure and construction material.

Abstract: A set of Mindlin plates bonded together is subjected to loading by impact, which is considered to represent a generic engineering structure and is analyzed through numerical simulation. The objective is to identify optimum configuration in terms of loading, structural dimensions, material properties and composite layup associated with micrometeorites impacts on spacecraft that will not penetrate into its structure. Following the algorithm developed for the problem, the work comprises an in-depth analysis of a generic flat plate structure subjected to impact and numerical simulation. The analyses are based on dynamic response with emphasis on the elastic region. The direct numerical simulation is carried out in parallel for the analysis, synthesis, parametric study and optimization. As simulation case study, the panel structure response to impact loading by a spherical rigid body at certain velocity perpendicular to the panel plate itself and numerical simulation is carried out as appropriate. Simulation results are validated through comparison with analytical work. The entire scheme carried out in this work is a novel comprehensive approach for the structural design of non-penetrated impact on metallic composites. The results show that the use of composites, in particular the bi-metallic composite, is instrumental in tailoring the plate materials to achieve non-penetrating impact.

Abstract: This paper presents a method of finite element modelling used for the impact analysis of a composite panel. In this research, the composite panel consists of an oxygen mask locking panel of an aircraft. This panel is loaded with one concentrated abuse loading and three uniform distributed abuse loading cases and the stress variation within the composite panel for each load case is determined. In order to assess the impact analysis on the oxygen mask panel of the aircraft, a finite element model is created using Patran as the main application for pre/post-processing and Nastran as the main processor. The paper also presents a comparison between results obtained using the same finite element modelling of the composite panel CAD model of the panel with four load cases with different material types. The results are used to determine the most capable material stresswise.

Abstract: In light of the increasingly prominent environmental problems and disputes of the power transmission transformation engineering, analysis many of the environmental impact of 500 kV power transmission transformation engineering, introduce the related standards of electromagnetic environmental impact, focusing on the analogy analysis and theoretical prediction for the electromagnetic environment around typical 500 kV power transmission transformation engineering , analysis the condition of the power frequency electromagnetic field and radio interference which generated by power transmission transformation engineering effects on the environment. put forward the countermeasures and technical measures to solve and alleviate the problem of environment .

Abstract: This paper presents a novel pin-fixed aseismatic connector for bridges. A feature of this device is that the anchorage areas of both ends are connected with hinges; thus, there are no restrictions with respect to their mounting angles. Additionally, the PC cable of this device is given an appropriate amount of sag; thus, within the range of the sag the structure is capable of absorbing the amount of displacement because of temperature changes and live loads. In addition, this device has a certain shock-cushioning effect because of the rubber material surrounding the hinge pins. However, there is no quantitative evaluation method on the shock-cushioning effect of this device. Therefore, in this study, the shock-cushioning effect of the novel pin-fixed aseismatic connector for bridges is investigated using impact load tests and numerical analysis. It is found that the shock-cushioning effect of this device is almost equal to similar aseismatic connectors. Furthermore, it is also confirmed that their effects can be quantitatively evaluated using impact response analysis.

Abstract: High-speed tensile tests were carried out to investigate strain rate effect on both yield stress and failure strain using ASTM D1822 Type-S specimens made of polycarbonate. Based on test results, parameters for a material model suitable for polymers are determined, and numerical analysis is carried out to simulate test results. The material model is used to simulate tensile test using a dog-bone specimen and Charpy test other than the tensile test of Type-S specimens. It is found that good predictions can be obtained when rate dependent material parameters are used. Further, the high-speed tensile test considered in the present study is suitable for selection of parameters for material modeling of polymers for impact analysis.

Abstract: The purpose of the research is to assess the increase of the muscle strength and power. Movement of the human body when the moving one impacts a stationary or moving body is taken under consideration. The waveform produced by an impact is transformed into frequency domain. The acceleration record is transformed as a complex spectrum, by the use of a Discrete Fourier Transformation. In this paper the applications of the discrete Fourier transform is discussed and it was pointed out that it can be fruitfully applied to analyze movement techniques during competition or training exercises. The acceleration response spectrum contains knowledge about efficiency of certain techniques. It has distinct features which can show that the energy is concentrated around several discrete frequencies. Data from the shape of a frequency response spectra curve can provide the coach and the performer with valuable information on technique and also give information on recommendations with respect to corrections and adjustments that can lead to performance enhancement. In this paper, the technique of a database creation is proposed what allows us to establish a particular set of circumstances under a specified protocol to observe and evaluate the implications of the resulting observations.

Abstract: With the development of electric vehicles technology, especially the development of battery technology and strongly supported by some developed countries in terms of policy, electric vehicle has undergone a rapid expansion in recent years. A lot of electric vehicles are popularized and applied, which will have an impact on power system especially the distribution system. Therefore it is necessary to study the demand characteristics of electric charging and the treatment method and model of access to the network. With this understanding, this article studies the power output model of electric vehicle and analyzes the impact to the distribution network load, the network loss and voltage with different electric vehicles capacity.

Abstract: Under the call of energy conservation and emission reduction in the whole world, the hybrid cars with its good fuel economy become the important vehicle mode. The ordinary passenger is converted into a hybrid passenger, in order to meet the power performance and fuel economy of the hybrid bus and the power control requirements, the ordinary passenger must be modified design mainly equipped with assembly parts. This article mainly design assembly parts arrangement position of the equipped later, and make the front and rear axle load difference of the hybrid passenger and the original passenger be not large, to ensure all performances of the hybrid electric passenger. Then for the whole vehicle arrangement parameters variation, respectively analyze the quality parameters.

Abstract: At present, mechanics properties of composite at home and abroad only include data of the single-layer board. On the basis of researching literature of composite finite element analysis, approaches of setting composite three-dimensional parameters based on the parameters of single-layer material are summarized. By three-dimensional finite element analysis on composite whole cockpit, the impact of uncertain parameters on cockpit analysis results is studied. Adopting maximum stress criteria, maximum strain criteria and Tsai-Wu criteria to evaluate the initial failure of composite whole cockpit, the impact of material uncertain parameters on initial breaking strength prediction of cockpit is studied. The study can provide reference for three-dimensional finite element analysis of composite whole cockpit.