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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.

The reliability of security system affects the ability of the system to protect people's lives and property safety. Failure risk assessment of security system is an effective method to test the reliability of the system. The fault tree analysis method has been applied to analyze the system failure risk from the angle of each part and considering the human factors. The traditional fault tree analysis method assumes that the probability of bottom events is certain to calculate the top event probability. To obtain accurate bottom events probability is difficult, even impossible because statistical data is not sufficient and the bottom events is fuzzy in fact. Analysis of the fuzzy mathematics theory is introduced into the fault tree. The calculation provides reference for the system design and management.

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.

The mathematical model of automobile driving was established, the calculation method of standing start acceleration time based on principle of optimal power continuous shift was introduced. The simulation analysis, calculation and verification were conducted by MATLAB. It lays the theoretical foundation for the analysis and calculation of dynamic performance by computer.

Phosphate is widely used in frozen aquatic products. In this study, frozen Pollock was taken as raw materials, and the effect of different phosphates (sodium pyrophosphate, sodium tripolyphosphate and sodium hexametaphosphate) on weight gain, thawing loss and cooking yield of Pollock fillets were studied. The results showed that with the increasing concentration, the weight gain and cooking yield of sodium pyrophosphate and sodium tripolyphosphate treatment groups increased, and the thawing loss reduced, whereas sodium hexametaphosphate treatment group remained unchangeable. The optimal proportion of sodium pyrophosphate, sodium tripolyphosphate and sodium hexametaphosphate on Pollock fillets was 3:2:3 and the concentration of mixed phosphates was 4%, and the weight gain, cooking yield and thawing loss was 17.1%, 88.6% and 2.7%, respectively

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.

The article indroduced the system of ore mixing of sintering based on data mining. Appled the method of cluster to the saved history data of the sintering process to classfy the history data into three category. Every new sample should be put into the Corresponding cluster by the distance of Eucliden, at the meantime, find the nearest proportioning ore case, and the quality index of the new sample is same with the nearest case. The method is more useful and easy.

Protein hydrolysates from Tuna frame (TFPH) and Pollock frame (PFPH) were prepared by papain, respectively.The yield, the basic composition content, the antioxidant activity and functional properties (solubility, emulsifying and foaming ability) and the degree of hydrolysis of the protein hydrolysates were evaluated. Results suggest that solubility, antioxidant activity of protein hydrolysate from Pollock frame are better than that of tuna frame, but the yield is lower than that of tuna frame.

Currently, research on wetlands is a rapidly developing field. To understand the state of wetland science in China, we used the term “wetland” ,“marsh”, “swamp”, “bog” and “mire” as the keywords to search in the ISI Web of Knowledge and the Chinese Journals Full-Text Database and collect Chinese and English literature on wetland written by Chinese researchers. These publications were analyzed with bibliometric methods by the distribution of the publication year, the author and organization distribution, the journal distribution, the research funds, the research regions and the subjects. The results indicate that core research groups working in the field of wetland science in China have already been formed, although the distribution of research groups was scattered across many institutions and universities. Dispersion and concentration coexisted in the journal distribution of Chinese and English publications—the majority of publications were clumped in a small number of journals, while a minority was scattered in a large number of journals. In China, there are two professional journals publishing papers on wetlands, Wetland Science and Wetland Science & Management. However, it is reasonable to launch an English language wetland journal in the country to enhance communication and cooperation. Research funds for wetland science have a wide array of sources. An important portion of the papers in Chinese was supported by the National Natural Science Foundation of China and provincial foundations, while those in English were supported either by National Natural Science Foundation of China or international funds. Field studies in wetland science were mainly conducted in the regions with great valleys. Wetland hydrology, Wetland Biogeochemical process and Wetland protection and management are the main objects of those studies. With the development of economy, many environmental and resource issues have emerged due to the excessive use and subsequent destruction of wetland areas. Thus, enforcing the protection of wetlands is becoming increasingly popular.

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.

It is often needed in engineering that detecting and analyzing vibration signal of some equipment. To meet the requirement, a portable detecting and analytic instrument was designed using virtual instrument concept. In the instrument, notebook computer was used as the platform of hardware. Vibration signal was obtained by integrated piezoelectric acceleration sensor (DTS0104T), and was transferred to a notebook computer through data acquisition card (NI USB-6210) based on USB bus. The software, running on the notebook computer, was developed under LabVIEW. Vibration signal could be displayed on screen, recorded in disk or printed by printer, retrieved, and analyzed. The analysis functions of the instrument include: time-domain analysis, frequency-domain analysis, time-frequency domain analysis, and correlation analysis. The instrument is compact, portable, powerful, and with friendly interfaces, has broad application prospects.

To adjust temperature as the requirement of process curve, an intelligent control system of temperature was designed. In the system, the fuzzy rule was used to adjust parameters of PID controller. Adjusted PID controller was used to control the change of temperature. The system can avoid the disadvantages of common PID, such as, long setting time, wide overshoot, and acquire better control characteristic. It were expatiated that principle and method of control. The hardware structure and the software flow chart were also introduced.

To improve precision of reverse design in cam contour curve, method of using BP neural network was presented. The theory and algorithm of BP neural network were introduced, the principle and process of BP neural network modeling used in the reverse design of cam contour curve were expounded, and the actualize method of reverse design with modeled network was afforded. Experiment indicates that this method is suitable to reverse the contour curve of cam, and has high approach precision. At last, disadvantages of the method were discussed.

In order to improve water quality retrievals of multi-spectral image accurately, this paper puts forward a method for water quality remote retrieva based on support vector regression with parameters optimized by genetic algorithm. The method uses SPOT-5A data and the water quality field data, chose four representative water quality parameters, support vector regression are trained and tested, the parameters of support vector regression are optimized by genetic algorithms. The result of experiment shows that the method has more accuracy than the routine method. It provides a new approach for remote sensing monitoring of environment.

The Mercenaria mercenaria protein hydrolysates (MMPH) and Ruditapes philippinarum protein hydrolysates (RPPH) were prepared by three enzymatic methods, and the radical scavenging activity of the protein hydrolysates was analyzed. The results showed that the protein hydrolysates prepared by the combination of Protamex and Flavourzyme exhibited significant radical scavenging activity; For DPPH radical, the EC50values of MMPH and RPPH were 33.0 mg/mL and 93.0 mg/mL, respectively, and for hydroxyl radical, the EC50values of the protein hydrolysates were 7.5 mg/mL and 7.0 mg/mL, respectively; The protein hydrolysates were further fractionated by ultrafiltration membrane of 6000 Da, and the radical scavenging activity of the resultant fraction with lower molecular weight (50values of MMPH and RPPH fractions were 29.5 mg/mL and 58.5 mg/mL, respectively, and for hydroxyl radical, the EC50 values of the fractions were 6.0 mg/mL and 7.0 mg/mL, respectively.

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.

Fish wastes such as bones and skins, has been under-utilized. Gelatin was extracted from frozen Arrowtooth flounder (Atheresthes stomias) skin (AFS), and the edible gelatin film was successfully prepared. The results showed that the proximate composition of moisture, protein, lipid and ash of the extracted gelatin was 6.0 %, 92.8 %, 0.31 % and 0.39 %, respectively. The pH, bloom strength and viscosity of gelatin was 6.0, 234.8 g and 4.3 mPa.s, respectively. The tensile strength (TS), elongation at break (EAB), solubility and the prepared edible film were 10.3 MPa, 51.4 %, 98.3 %, and the film was transparent.

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 rapid development of Graphic Processor Units (GPU) in recent years in terms of performance and programmability has attracted the attention of those seeking to leverage alternative architectures for better performance than that which commodity CPU can provide. This paper presents a new algorithm for cutting display of computed tomography volume data on the GPU. We first introduce the programming model of the GPU and outline the implementation of techniques for oblique plane cutting display of volume data on both the CPU and GPU. We compare the approaches and present performance results for both the CPU and GPU. The results show that cutting display image generated by GPU algorithm is clear, frame rate on GPU is 2-9 times than that on CPU.

In view of the poor anti-noise performance of traditional methods, the principle of camera calibration is analyzed based on calibration template with planar circles, and a new calibration technique is proposed based on pin-hole perspective model. Firstly, the edges of image ellipses are located in sub-pixel by spatial-moment operator. Then elliptic equations are obtained by the Least Square Fitting method, and common tangents of two arbitrary ellipses are also calculated. Finally, the extrinsic and intrinsic parameters are computed by the Radial Alignment Constraint (RAC) model. Experiments results indicate that proposed method has a goof performance of lower computation complexity and higher precision.

In this paper, a new image enhancement method is proposed based on fractional differential, which can select the differential order automatically by the difference of mutual information (DMI). DMI describes the increase of mutual information in original and enhancement image. Being a measure of ascertaining the ehancement effect, it is considered getting the information balance in the images processed by different differential order. According to it, a criterion of selection differential order is put forward. Image convolutions are implemented with fractional operator in different scales, and then DMI of adjacent scales are calculated. The differential order can be selected in which the DMI is the mininum. The experimental results indicate that the proposed method is effective, and has better result compared with other methods.

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.