Advanced Materials Research Vols. 433-440

Abstract: Fingerprint segmentation is an important problem in fingerprint image preprocessing. This paper describes a new approach to the segmentation of fingerprint images based on fractal dimension. First, the Sobel operator is used to calculate the gradient of fingerprint image, and then we employ the concept of fractal dimension to further analyze the image produced by the first step. By estimating the fractal dimension of the foreground and the background of the fingerprint, and combining grayscale as features, finally accomplish the segmentation of fingerprint. The experimental results show that the proposed method performs well in fingerprint segmenting and is better than the existing method.

Abstract: Typical characteristics of web manufacturing process ,when compared with other sheet or flat product manufacturing, are the large value of web width and production speed .So the development of new and efficient algorithm invokes the interests of many researchers. This paper describes a novel approach based on stationary wavelet transform for the segmentation of web surface defect. The segmentation is performed firstly by decomposing the gray level image into sub-band images and then by an image fusion scheme for the sub-images. Compared with orthogonal wavelet transform (OWT), the notable advantage of stationary wavelet transform (SWT) is its shift invariance. These properties are especially important for defect detection. Image fusion makes full use of available information in each sub-band images to obtain better output results when compared with ordinary image enhancement. Experimental results demonstrate the validity of our method. The proposed method is targeted for web surface defect inspection but has the potential for broader application areas such as steel, wood and fabric defect detection. With the development of high performance signal processors, spectral analysis or a combination of statistical and spectral analysis would be the trend of web surface defect inspection.

Abstract: the problem of software aging widely exists in long-running software system, and the solution is software rejuvenation. Traditional software rejuvenation strategy has some deficiencies in solving the problems of discrete web services aging, for example, the higher failure rate and the poorer stability. Therefore, considering the discrete web services has the loose coupling characteristic, we establish and revise the discrete web service aging damage model by using multiple linear regression method to calculate the aging damage of an individual web service. On this basis, based on the web service priority, call frequency and aging condition, we propose an adaptive rejuvenation strategy which ensures the key web services’ quality. The experiment result shows that, compared with traditional rejuvenation strategy, this strategy improves the stability and dependability of the web services.

Abstract: Structural analysis of wind turbine blade is a necessary part in the process of blade design. Based on the ANSYS software, the stress and strain distribution analysis of a kind of 1500kW horizontal axis wind turbine blade is carried out at the action of ultimate flapwise loads, the vibration mode shapes of this blade are also analyzed in this paper, thus providing some reference value for the larger-scale wind turbine blade on structural design．

Abstract: CNC machine, especially CNC milling machine, is the main production equipment in the industries of machinery, iron and steel, automobile manufacturing and so on. However, the errors are the main constraints to the processing quality and the precision measurement of CNC machine. Based on the multi-body system theory, the article models the error of Siemens CNC milling machine. In terms of the analysis of the error model, it is argued that the processing precision of CNC milling machine can be improved through controlling and compensating the error in the process of installation and manufacturing.

Abstract: Bridge decks in composite bridges endure local vehicle load directly and failure is apt to occur in bridge decks, so the decks in Jiubao Bridge were designed to be renewable components. Space finite element model of Jiubao Bridge was established. Stress variation of upper and lower edge of the girder under dead load was analyzed when each deck changed locally. Stress variation processes of various whole span replacement plans had been analyzed and the stress envelope was obtained. The calculation results show that local bridge deck replacement has no obvious influence on the steel girder stress. While the plan that remove bridge decks from mid-span to arch foot has less influence on the girder stress compared to other whole span replacement plan.

Abstract: The dependence of chemical equilibrium constant on the reaction temperature and pressure and the feed molar ratio were theoretically calculated for indirect ethanol synthesis from syngas through the coupling of CO with methyl nitrite (MN) to dimethyl oxalate (DMO) and the hydrogenation of DMO to ethanol. It shows that the coupling process and the hydrogenation of DMO to ethanol are highly favorable at all temperatures and pressures, especially at low temperature. The hydrogenation of DMO to ethylene glycol (EG) and the further reaction of ethanol with H2 to high alcohol are thermodynamically favorable at low temperatures, below 630 and 450 K, respectively. Additionally, high reaction pressure is facilitated to EG and high alcohol formation. Accordingly, moderate reaction temperature (up 538 K) and low reaction pressure (below 1 MPa) are beneficial to ethanol production.

Abstract: It is significant to make researches on drag reduction in two-phase transport pipeline because two-phase flow has high energy dissipation. API X 52 steel pipe with diameter of 40mm is used in this paper to simulate pipeline with different inclination geometry including horizontal, up-inclined and vertical sections. The up-inclined section has an inclination angle of eight degree. Experiments and theoretical analysis are carried out to study the drag reduction characteristics of gas-liquid two-phase flow in these three sections. The drag reducing agents used here is polyacrylamide. It is found that two-phase drag reduction varies with pipe inclination geometry. The largest drag reduction efficiency occurs in horizontal pipes and which is up to seventy percent. Drag reduction efficiency in up-inclined section is up to sixty percent. Drag reduction in vertical section is the lowest and which can be up to about thirty percent. A mechanistic drag reduction model is proposed to predict drag reduction in gas-liquid two-phase flow. The results predicted are in good agreement with the experiment data.

Abstract: In view of wide attention to global climate change, “low carbon city” has been the greatest object for all cities in the world. Urban landscape is vital to urban construction and economical development. In this paper, it was researched how to guide people to develop low-carbon habits to achieve mitigation in the field of energy conservation through landscape design. The new method of urban low-carbon landscape design was studied from five aspects, including urban landscape patterns, green space, nightscape design, and so on. On the other hand, the low-carbon aesthetics should be built up through landscape design in order to construct an integrated theory system of landscape design for low carbon city.

Abstract: The island operation is a new operating mode of the distribution network after the distributed generation is introduced. And it is a beneficial supplement for the operation of the distribution network. The distributed power supply capacity is made full use to ensure the safe operation of the maximum number of significant load when the fault occurs. A combinational algorithm of the planned island partition is presented according to the principle of power balance in the distribution network failure. Heuristic search strategy and the breadth-first search algorithm are adopted by taking into account the characteristics of different types of distributed power. The validity of the method is proved by the example.