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This paper takes the large space air-conditioned buildings air-conditioned buildings as research subjects and sets numerical conditions of large space air-conditioned buildings prototype to conduct a simulation study by means of numerical simulation.Numerical and experimental results show that the standard k-εturbulence model can be used to describe the characteristics of the large space air-conditioned buildings building;the experimental results of a typical location room temperature basically consistent with the numerical results of the prototype and enlarged model.Results of this study will provide a useful reference for the researches of large space air-conditioned buildings air-conditioned building.

According to the chatter phenomenon of 3rd stand of a steelworks six-roller tandem cold mill (TCM), vertical vibration of tandem cold mill was simplified to eight degrees of asymmetric freedom mass-spring system. Virtual prototype model on vertical vibration of tandem cold mill was established and natural frequencies and main vibration mode of mill were solved by using automatic dynamic analysis of mechanical systems in software ADAMS. The modal coordinates of main vibration mode of the mill were referred firstly and obtained; the maximal mode of vibration system was found and finally discovered the fifth-octave-mode chatter was the probable vibration of the mill.

Redispersible polymer powder of vinyl acetate and versatate copolymer (VA/Voeva) used as admixture additive, is introduced to modify lightweight cement mortar with ground granulated blast furnace slag, quartz sand and expanded perlite as aggregates. The effect of the dosage of redispersible polymer powder of vinyl acetate and versatate on the compressive and flexural strengths was investigated in details. The ratio of compressive strength to flexural strength (σc/σf ) of cement mortars varied with the variation of the dosage of redispersible polymer powder. Scanning electronic microscopy was used to investigate the internal structure of the polymer-modified lightweight cement mortar. The result showed that the toughness of the polymer-modified lightweight cement mortar was improved with the increase in the dosage of redispersible polymer powder, and the network membranous structure formed by the polymer attribute to the improvement of the toughness and flexural strengths.

In order to solve the problem of the photo response non-uniformity (PRNU) for High Dynamic Range (HDR) video system, this paper discusses the causes of the problem and the common solution, and then proposed a new non-uniformity correction approach based on the reference source for HDR video system. This approach use high-pass filter to calibration image in Frequency domain to get the correction matrix of one level light conditions at first. And then performs an inverse Fourier transform to the spatial domain. Finally calculate the difference between the correction matrix and the target image to obtain the corrected results. The experimental result indicates that the approach has good effect on dealing with non-uniformity of the HDR images and the definition has been greatly improved.

A new type of lightweight cement mortar was developed by using ground granulated blast furnace slag, quartz sand and expanded perlite as aggregates which were mixed with cement homogeneously. Consistence was used to characterize the workability of lightweight cement mortar. The effect of the components, including the proportions of granulated blast furnace slag and the addition of fly ash, on the properties was investigated in details. The results showed that the values of compressive and flexural strength increased with the ratio of slag to sand. Additionally, the introduction of fly ash improved the consistency and strength properties of lightweight cement mortar.

With the electric turret work principle, analysis the fault of the CNC lathe turret.Aimed at different fault phenomenon, the fault diagnosis method was proposed. Introducing the specific application of fault diagnosis method through specific cases, provide a theoretical reference for effective control failure and rapid troubleshooting

SQLite has been widely applied in embedded system because of its open source and less resource consumption. A novel optimization method with Red-black tree replacing B tree in indexing mechanism in order to solve the low efficiency and large energy consumption problem when inserting and deleting data in SQLite database was proposed in the paper. The contrast test of efficiency of between red-black tree and B tree while inserting and deleting data shows that this method can effectively improve the SQLite insertion and deletion operation efficiency and reduce the energy consumption.

This paper carries out a series of experimental study on 6 column specimens, analyses and compares with the different parameters on the axial loading tests of RC columns and RC columns strengthened with steel tube. The experimental results show that the RC columns strengthened with steel tube take full advantage of loading properties of both materials, thus greatly improve the bearing capacity of specimens. With the same wall thickness steel tube, the improving degree of bearing capacity of long columns is bigger than the short columns, and the reinforcement effect is more obvious. The experimental results can offer reference for scientific research and engineering staff, and promote this reinforcement method to be widely used in engineering practice.

To understanding future market conditions of agricultural pumps in Henan province, need to predict numbers of agricultural pumps at each year-end. Expatiated the principle of prediction based on BP neural network, and constructed the model of prediction. The BP neural network was trained with normalized statistical data of agricultural pumps in Henan province from 1990 to 2010, and gained parameters of the neural network. Test shows the model has high predictive precision. The average absolute value of predicted relative errors is 1.333%. Numbers of agricultural pumps at each year-end in Henan province of China from 2011 to 2015 were predicted, and the trend was also presented.

Focused on the facial feature points localization, the enhance ASM algorithm based on modeling texture by the DCT-SVM is proposed. First, the statistical shape model is built. Then, some key feature points are selected and their texture models are built by the DCT-SVM. In the subsequent searching, the feature points are divided into two classes based on their reliability gained by DCT-SVM detector, by combining the reliable feature points to the shape constraint, the original shape can finally match to the target face. Experiments show the algorithm is robust to the expressions change and can better locate the features than the traditional ASM.

In order to improve detection efficiency of casting bolster and side frame of railway freight car, the method to automatically detect railway casting porosity and shrinkage cavity using watershed transformation based on X-ray digital radiography is presented. Firstly, while castings of a bolster and a side frame are scanned by 9Mev X-ray digital radiography system, the DR images are obtained. Then one of interested regions is selected in an image. Defects segmentation is implemented by using watershed transformation algorithm in this paper. Lastly, defects area and occupy rate are acquired by analyzing and computing, so that we can judge the casting quality. The experimental results show that defect regions and contours can be accurately acquired. This method has high robustness and practicality. It improves the efficiency of automated inspection of railway castings.

The evaluation of stresses in engineering structures to provide early indications of stress status is a fast growing area in non-destructive testing. Metal magnetic memory technique is the magnetic stress measurement technique for ferromagnetic materials using passive magnetic fields to monitor changes in the magnetic properties of materials. This paper studied the physical formation process of metal magnetic memory effect. This paper studied the physical mechanism between stress and magnetic field in metal magnetic memory effect, through the influence of stress-induced magnetic anisotropy on magnetization process of ferromagnetic crystal.