Applied Mechanics and Materials Vols. 55-57

Abstract: In this paper, based on measured data of practical engineering, the characters of single short pile under the static vertical load action in the normal stratum combination model of dualistic structure has been simulated by using ABAQUS finite element software. Then simulated result and measured one has been compared and analyzed carefully. The analysis result indicated the applicability and reliability of ABAQUS finite element software in the simulation analysis of short pile. All these can provide some theoretical reference for design of short pile foundation.

Abstract: Three-layer BP neural network, particularly using Levenberg-Marquardt back-propagation with early stopping algorithm, is widely used in curve fitting, attributing to its fast speed and free from over-fitting. Hence, the trained network by Levenberg-Marquardt back-propagation was used for curve fitting of the radiation spectrum of blast furnace raceway. The results showed that Levenberg-Marquardt back-propagation with early stopping algorithm presented a better fitting ability. Additionally, the results of spectral fitting model showed that the blast furnace raceway had an effective radiation spectrum in the wavelength range from 420nm to 880nm, where the raceway could be considered as the gray body radiation.

Abstract: In this paper, we deal with the finite-time chaos control of the chaotic financial system. Based on the control Lyapunov function (CLF) theory, the control law are proposed to drive chaos to equilibria within finite time. Numerical simulations are given to show the effectiveness of the proposed controller.

Abstract: A new method, non-parametric kernel density, is used to research the distribution function of HangSeng index returns. The new method can not only depict the character of peak and fat tails of stock returns, but also capture the market risk better than normal distribution. Further more, more accurate conclusions are concluded.

Abstract: In order to verify thermal comfort of a 12-meter-long highway sleeper coach equipped with a four-ducted air-conditioning system, the thermal environment inside the passenger compartment was numerical investigated with RNG k-ε turbulence model. Also, discrete ordinates radiation model was applied to consider the effect of solar irradiation. The characteristic distribution of the airflow organization and temperature field were obtained and compared with experiment results. Results show that the air flow and temperature distribution inside the passenger compartment are not uniform and greatly influenced by solar radiation and air inlet parameters.

Abstract: The purpose of this study is to investigate the effect of boundary conditions on the temperature distribution and thermal comfort of a radiant floor heating system and their practical application to commercial buildings. Indoor thermal environment, along with human response, was studied by means of CFD. The three-dimensional temperature distribution was numerically simulated with the zero-equation turbulent model. And two typical operating models, which there is and there is no windows in the room were analyzed in detail. The results show that the radiant floor heating system can meet the demand of comfortable degree, and that the temperature field is enormously influenced by boundary conditions. It is necessary to install curtains to decrease the radiant heat transfer of the cooling glass surface and other control methods to ensure the room to be a thermal comfortable environment.

Abstract: This paper analyses the transient response of second-order system through time domain analysis, root locus and frequency domain analysis, meanwhile, studies the influence exerted to the system by the second-order system damping ratio and the coefficient ratio as well as the research and damping ratio associated with the relevant parameters, like delay time, rise time, peak time, overshoot, time regulation, basing on the unit step response, and the stability of the system is studied by root locus. Finally, graphics are built through the application of Matlab in order to have an intuitive understanding of the impact on the performance of the system.

Abstract: The content of heavy metals (Cu, Cr, Cd, Pb, Zn and Ni) was determined by Atomic absorption spectrophotometer (AAS) and their distributions were analyzed in various waste incineration slags. The results showed that the particle size less than 5mm were a major component in the slag, which were about 59.42% in all the incineration slags. The content of heavy metals was different in the incineration slags. The content of heavy metals Zn, Cr and Cu were significantly higher than that of other heavy metals and that of Pb was in second, followed by Ni, and that of Cd was in the least. The contents of these heavy metals were higher than that of the soil environmental quality standards (GB15618-1995) and the background values in soil of Guangdong. The distribution of heavy metals in different particles of the slag were very different, in which the content of Cr, Zn, Cd and Ni were higher in the small particle sizes, but that of Cu and Pb was not obvious in various particles. In all, the content and distribution of heavy metals were mainly with composition of the waste and the heavy metal characteristics.

Abstract: ARM is the newest 32-bite RISC microprocessor. Its high performance, low power consumption and flexible extension make ARM particularly suitable for designing embedded system. Therefore, the realization of the FAT16 file system with ARM can satisfy the demand of file storage in embedded system. This article descripts the simple realization of FAT16 file system with ARM 7.

Abstract: This paper focus on the problem of asymmetrical evaluation level caused by the difficult of discrimination of internal and external defects of MFL inspection signals of oil well pipes to analyze the difference of change trend between the peak-to-peak value of normal detection signals of internal and external defects and the liftoff distance z. The liftoff characteristic is verified through experiments that the liftoff effect of internal defects has a gently change rate but the external has a sharp change rate. A double liftoff inspection method was further proposed, that was, there were double layers magneto sensors arraying in line in the normal direction to accomplish grads measure of two special spaced points in the liftoff direction. Then made cross correlation contrast of detection signals. Result in a new evaluation using the damping decrement of the peak-to-peak of inspection signals in the direction of liftoff. Finally, the unitary damping decrement as an evaluation value used for direct judgment was presented and confirmed by experiments, indicating that the proposed approach was of feasibility.