Advanced Materials Research Vols. 301-303

Abstract: In order to study the double-cones flowmeter’s varying mechanism of expansibility factor, the experiment on the flowmeter with certain double-cones rate of diameter for 0.4、0.5、0.6 is carried out firstly, witch compared with the result of computational simulation. They are almost the same. This ensures the correctness of simulation. Then, we get the predictive formula of expansibility factor for the double-cones flowmeter through a mass of simulation study on the flowmeter with certain rate of diameter for 0.4、0.5、0.6、0.7、0.8、0.9 using Fluent.

Abstract: Due to the feasibility and the efficiency in image engineering, Grey Theory proposed by Julong DENG has been paid more attention by many researchers at home and abroad. The feature of the theory lays in the fact that modeling or analysis is easy to implement even in the condition that only few samples are available. Many research fruits on digital image are produced so far. Focusing on edge detection of digital image, this paper gives a survey of the application and predicts some future developments after some basic theory are described.

Abstract: To increase the speed of image matching, this paper combines Bacterial Foraging Algorithm (BFA) of swarm intelligence with wavelet transform, and presents a fast matching method. The method regards the problem of image matching as a search for the optimal solution. To provide artificial bacterial swarm algorithm with an appropriate fitness function, the Normalized Product correlation (NPROD) is employed to measure the similarity between the template image and the searching image. Then the best coarse matching position is gradually approaching by chemotaxis, elimination and dispersal, and reproduction behaviors of artificial bacterial. Finally, the best matching position is found out according to the coarse matching position. Experimental results show that the proposed method is fast and efficient.

Abstract: This paper studies the multiple events character of pedestrian platoon with the technique of video analysis. Meanwhile, applying K-means cluster, we select three criterions which are the average speed, the width and the length of pedestrian platoon, the crossing process was divided into multiple events at signalized intersections. The application of cluster analysis in the division of multiple events was proved through case study, and it reflected the phased characteristics of pedestrian platoon.

Abstract: This paper presents an approach to determination of acoustic admittances by solving inverse problem which is obtained from finite element modeling. The authors detail the inverse problem and its general eigen-function and introduce an optimization method to obtain boundary conditions by known geometries in a discrete domain and the lowest propagating frequencies and their corresponding attenuations. This method is practical because it only needs few eigen value information rather than full information of the eigen values. Comparison of acoustic experimental results and calculated results, which match well, is given to validate the method.

Abstract: In order to improve work stability and measurement accuracy of drilling inclinometer, and overcome the poor stability of Elman networks and lower compensation precision of genetic Elman neural networks, we combined ant colony algorithm and neural networks, using the Adaptive Ant Colony Algorithm that its pheromone evaporation factorand pheromone update strategy adjust adaptively to optimize Elman neural network weights and thresholds, and applied it to drilling inclinometer sensor compensation. Simulation results show that the compensation effect of adaptive ant colony Elman neural networks is better than that of Elman networks and genetic Elman networks, the compensation accuracy is 10^-8.

Abstract: The variational method has been used to study the interaction between the two polarized components of the vector dark soliton in a birefringent fibre. The interaction energy and force between the two components of the soliton have been derived, and then the propagation properties have been discussed in detail.

Abstract: To explore the relationship between basal metabolism of the nicotinamide and the athletic ability of the elite swimmers, Sixteen Chinese male athletes participated in the short distance swimming competitions in the 15^th Asian Games were recruited. Their morning urine samples were collected three times in a row, once a week in the month before the games, and the metabolite of nicotinamide, N-methylnicotinamide, was measured using nuclear magnetic resonance (NMR). Then the subjects were classified as finalists group and non-finalists group according to their performance in the games, and mean comparisons of the measured results was carried out between the groups with SPSS15.0. The relative concentrations of MNA in the urine from finalists group were significantly higher than from non-finalists group in every comparison (0.0000524 ± 0.0000281 VS. 0.0000195 ± 0.0000131, P<0.05; 0.0000221 ± 0.0000181 VS. 0.0000162 ± 0.0000151, P<0.05; 0.0003831 ± 0.0000373 VS. 0.0000636 ± 0.0000118, P<0.05). Higher level swimmers have relatively higher metabolic rates, which may help to form a more effective energy supplying mechanism and a higher tolerance to intense training and severe competitions.

Abstract: The physical characteristics of athletes are the important indexes for athletes selecting and training monitoring. Through measuring the physical characteristics of the 152 canoeists taking part in the Chinese Fifth Intercity Games and analyzing the data with factor analysis model, the most important factor of canoeists’ physical characteristics, degree of brawniness, was found, and the first ten indexes which can perfectly represent the physical characteristics of canoeists were identified.

Abstract: A series of experiments on the corona current pulse appearing on insulators under various contamination conditions with AC voltage of different amplitude are described. The corona current pulses were found to follow the Gaussian distribution and can be used to distinguish the faulty insulators from normal insulator strings in transmission line. The probability formulas about the corona current pulses have been studied in detail. They can be used as a kind of criterions to detect the faulty insulators. With several established fuzzy membership functions of humidity and contamination through data from experiments, it is proved that the insulation state could be estimated from the transmission line insulator strings by the fuzzy logical reasoning. This method has been verified in the laboratory by simulating work conditions of insulator strings on an 110kV transmission line and has the advantage of safety and convenience.