Advanced Materials Research Vols. 201-203

Abstract: A method for continuous box-girder bridge structure finite element (FE) model updating based on static-load testing is proposed. The procedure includes field static-load testing, FE modeling, FE model (parameter) updating, etc. Based on this procedure, the structure FE model updating for an expressway 5-span pre-stressed concrete continuous box-girder bridge is conducted. And the bridge structure static FE model, which is consistent with the static-load testing actual measure response, is gained. The updated FE model (parameter) is foundation of structural performance evaluation for the bridge.

Abstract: It can provide theoretical guidance for the prevention of soil erosion and planting structure adjustment to study on fractal characteristics of soil particle-size distributions under different landform and land-use types. Soil particle-size distribution (PSD) is one of the most important physical attributes due to its strong influence on soil properties related to water movement, productivity and soil erosion. The fractal and multifractal measures were useful tools in identifying soil PSD with different taxonomy. Land-use type, as one of important factors to affect soil PSD was paid little attention in the previous research. In this paper, the theory of soil particle-size fractal was applied to characterize PSD in soils with the same taxonomy and different land-use types. Then the effects of land use on the fractal and multifractal parameters were analyzed. The study was conducted on the loess hilly areas of the Loess Plateau in Nanxiaohegou basin of Gansu. Soil was sampled from 18 land use types. The soil PSDs were obtained by sieving and pipette methods. The result showed that: (1) the mass fractal dimension of soil particles was significant correlated with the soil mass clay content; （2）both the soil mass clay content and the mass fractal dimension of soil particles showed the same tendency of increasing with the soil layer， and the mass fractal dimension relates to the land uses and topographic feature. Thus they could be potential parameters to reflect soil physical properties influenced by land use. More significant result is required in the future study to test the applicability of fractal parameters in characterizing land use effect on soil particle-size distributions.

Abstract: To improve the accuracy of load forecasting is the focus of the load forecasting. As the daily load by various environmental factors and periodical, this makes the load time series of changes occurring during non-stationary random process. The key of improving the accuracy of artificial neural network training is to select effective training sample. This paper based on the time series forecasting techniques’ random time series autocorrelation function to select the neural network training samples. The method of modeling is more objective. By example, the comparison with autoregressive (AR) Model predictions and BP Artificial Neural Network (ANN) predicted results through error analysis and confirmed the proposed scheme good performance.

Abstract: A new boost converter without an inductor is proposed for a small-scale wind power generator system. Experiments were carried out to compare the output powers and power conversion efficiencies for the converter without an inductor and the one with an inductor. Experimental results for the converters operated at both constant resistance mode and constant voltage mode were given. It was found that efficiencies for the converter without an inductor and for the one with an inductor are essentially the same. The cost may be reduced since the inductor is not needed in the proposed boost converter without an inductor.

Abstract: The novel anionic gemini surfactant, isodium salt of N, N’, N”- trilauroyl-diethylenetriamine diacetate(TDAD), was synthesized with ethylenediamine, sodium chloroacetate and lauroyl chloride by displacement reaction and acylation reaction. The results show that TDAD has fairly low critical micelle concentration (cmc) and high surface activity. The adsorption isotherm of TDAD at the interface of oil sand/aqueous solution is taken on “S” model, and the adsorption loss of TDAD is much lower than that of the traditional monomer sodium laurate (SL).

Abstract: For low-grade and fine disseminated grain size hematite, there is no good effect through traditional mineral separation. In this study, hematite will be smelted directly to separate quartz and hematite.The optimal technological condition is as: reduction time is 60 min, reduction temperature is 1550°C and alkalinity of slag should be controlled between 0.3~0.5 in order to get better slag to form glass ceramics.

Abstract: This paper demonstrates an energy-efficiency supervision and diagnostic system (ESDS) to illustrate problems that the buildings do not perform as well as anticipated during design stage. The ESDS consists of a set of sensors, data acquisition system, data analysis and diagnostic system investigated on a web-based remote access system that can be worked to identify problems in practice. The states of monitoring and diagnosing building operations including the electricity consumption、water consumption、overall evaluation of energy consumption and air condition system was analysed in detail. The results show that the energy efficiency of this large public building has great potential during the practice.

Abstract: In many fields’ rough-terrain vehicles, e.g., mineral exploration vehicles, military applications vehicles, vehicles that can move on rough terrains are desired. The ability of obstacle-climbing was affected by stability of vehicle. The stability of vehicle is closely related to the body attitude, which composes with a number of bodies. For this reason, in this paper, a wheeled mobile vehicle with 2 DOF articulated frame (2DWAV), for example, the new concept of correlative stability is presented. The stability of 2DWAV was analyzed based on static and dynamic in this paper, when it was driving on rough terrain. Finally, the simulation and experiment on rough terrain are carried out.

Abstract: With consideration of the viscosity of semi-solid aluminum alloy slurry and the mold filling characteristics in die casting, the die-casting mould for semi-solid aluminum alloy has been designed and manufactured on the basis of the standard samples. The process of mold filling and solidification of semi-solid aluminum alloy in die casting was simulated by using ProCAST software. With combination of simulation results with die casting experimental data, the results indicate that the influence of heating system of the mould and cross section of ingate for the mould on flowing of semi-solid aluminum alloy in mould cavity is important in this work.

Abstract: In this paper, numerical simulation of a new type enhanced heat transfer burner was carried out by using the CFD commercial software FLUENT. Standard κ-ε turbulent model, P-1 radiation model and PDF diffusion combustion model were used to predict the influence of the combustor’s structure change on its performance in the combustion process. The results showed that: The added necking down at the outlet of the combustion chamber can significantly enhanced the jet action of the flue gas, the high speed flow flue gas formed a forced convection cyclical field, convective heat transfer rate was increased greatly and the temperature distribution in the furnace became more uniform, which guaranteed an excellent heating effect. New type of staged air distribution can promote the mixing of the fuel and air. Further more, it can improve the flame length to prevent the local overheating phenomenon during the combustion process. On the basis of the same total sectional areas, the added number of the jet orifice can also promote the mixing of the fuel and air to enhance the thermal intensity and thermal efficiency of the furnace.