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A study on the method of estimating gasoline engine radiated noise by measuring surface vibration is carried out. Firstly, the theoretical basis and test method is studied. Then an experiment is carried out on a four-cylinder gasoline engine. By measuring the engine surface vibration velocity, the sound power level of these engine parts and of the engine body is calculated. The result shows that the estimation of engine radiated noise is accurate. It shows the sound power level of gasoline engine can be predicted by surface vibration.

With the rapid development of China's construction industry, the production of construction waste has become a growth trend.Construction of waste treatment is urgently needed in the old main building demolition materials,crushed bricks and earth accounts for more than 90%.[1]Studies show that the root cause of a large number construction waste is that the awareness of the value of construction waste recycling still unclear.

Compared with natural aggregate, recycled aggregate apparent density, bulk density, porosity, water absorption, large crushing index value, which corresponds to aggregate different sources have different indicators, which largely of recycled concrete limits on the application.. In order to more efficiently improve the utilization of recycled aggregate, ensure the stability production quality of recycled concrete, source unknown and difficult to directly measure its intensity of waste concrete materials, at the time of the preparation of recycled aggregate, it is recommended to repeat loading, using different pressures from different standard strength of recycled concrete coarse aggregate crushed curve to use as a criterion to determine the source of their overall strength. Different in different sources of strength recycled aggregate crushing value mainly reflected on the bond strength.

Filler stiffness and confinement effect on the frame structure under horizontal loads, making the earthquake severely damaged in recent years with filler frame structure. Research shows that the actual stiffness frame structure with infill walls and internal force distribution and pure framework significantly different. In this paper, the equivalent model analysis bracing frame structure filler with actual stiffness, elasticity and structure from stage to stage of the internal forces shaping the distribution were analyzed. The results show that the stiffness of the contribution and the confinement effect filler by factors geometry, masonry materials, the impact of the framework is not the same, need to consider the specific analysis and structural design.

The traditional way of the matching between suspension parameters and vehicle performance is that we assess the matching of suspension design parameters through the driver's subjective experience, this will lead that the vehicle development cycle is long and high cost, meanwhile the matching during the parameters of suspension is blindness. With the development of computer technology, combining the modern design theory and virtual prototyping technology, based on multi-body system dynamics method, the virtual prototyping model of mini passenger car was built. By using understeering degree, roll rate and total RMS acceleration values as evaluation indexes, the orthogonal experiment was designed and the range analysis was carried out, and the effects of the suspension structure parameters on handling stability and riding such as suspension rate of front suspension and rear suspension, torsion stiffness of antiroll bar, damping ratio of front suspension and rear suspension and so on were studied. Then the remarkable factors are found, the final results supply guidance and support for the optimization of the suspension parameters.

Based on sound intensity and acoustic array methods, noise source identification of an engine is measured at idle condition. The main noise source of intake surface and exhaust surface are determined, also their frequency spectrum analysis. This two kinds of method testing results fundamentally agreed very well, and verify acoustic array method is more simple and easier than sound intensity method.

This paper focuses on the home-country factors determining the rapid growth of China's ODI and provides empirical evidence based on 66 countries panel data over 1991 to 2010. First, we expand the investment development path (IDP) theory by including financial factors to establish benchmark model. Then, we explore whether China's net ODI flow is excessive or insufficient by adding China dummy. Finally, we examine the special factors driving and hindering China's ODI by introducing interaction terms. The results reveal that China's ODI level is insufficient. The economic development, export and international reserve drive the growth of China's ODI, while crowing-out effect of domestic investment and poor financing condition are obstacles.

With the development of wall innovation, the appearance of regeneration concrete hollow block has an important operation significance for building energy saving and high efficiency recycling of waste concrete. The paper introduces a new green wall material—regeneration concrete hollow block and analyzes the feasibility of its application from the point of macroscopic and technical economy. The paper forecasts the direct and indirect economic benefits after its application in order to promote the extension of regeneration concrete hollow block.

This paper analyzed the cracking behavior of carbon fiber reinforced concrete beam under static load using the finite element numerical analysis. By the way of finite element numerical simulation and the method of increasing the load gradually to analyze the carbon fiber content influence on the beam cracking, crack developing, beam deflection and beam average crack spacing. By comparing with the simulation result of common reinforced concrete beam test piece, it turned out that the carbon fiber reinforced concrete beam has a good cracking and deformation behavior under the same ratio of reinforcement. Under the same load, both the carbon fiber reinforced concrete beam and the common reinforced concrete beam have a small deformation, but the carbon fiber reinforced concrete beam showed a better resistance to deformation as the load increasing, its deflection increasing extent showed an obvious decrease compared with that of the common reinforced concrete beams. Its crack width can be revised by the common reinforced concrete beam rules.

Mu method is a flutter solution technique based on frequency domain mu-analysis, which directly applies perturbation to dynamic pressure in aeroelastic equation of motion. In a previous study, the dynamic pressure perturbation was modeled as a purely real uncertainty, which could not guarantee the continuity of mu. To improve the continuity of mu, a small amount of complex perturbation is added to the dynamic pressure in addition to the real perturbation. Thus the mu method is improved with this mixed real/complex perturbation. Formulations and algorithm of the improved method are presented and validated with sample test cases. It is demonstrated that the improved mu method is more feasible and conservative than the original mu method due to the mixed perturbation.