Advanced Materials Research Vols. 143-144

Abstract: Every resource in social tagging system have hundreds even thousands tags. To every certain resource, tags always have different popularity. The higher popularity a tag has, the more it suit for represent features of resource. This paper first find Top30 tags are popular tags, but the average tagging rate is quite low while approaching the 30th tag. Thus, six groups of resource that have vary saved times are taken for further analyzing. In all six groups, Top9 tags have high ATR, as well as ATR deviation, which mean these tags have obvious advantages while compare with others. Thus we take Top9 as representative tags. Finally, a user profile construction algorithm is given out based on representative tags.

Abstract: Image compression technology has been the research focus in the field of image processing all the time. In this paper, Radix-4 FFT is introduced to realize limit distortion coding of image. The presented method aims to solve the problems of Fourier transform on existing complexity and long time-consuming, and it can reduce the number of data store by conformal symmetry of Fourier transform. Using Radix-4 FFT, the time-consuming can be highly shortened and two different kinds of quantization tables are designed according to image compression ratio and the quality of image.

Abstract: Gravitation search algorithm (GSA) is a novel meta-heuristic algorithm introduced recently. In this paper, a study of boundary conditions is presented indicating the invisible wall technique outperforms absorbing and reflecting wall techniques in this framework. Experimental results show that our method is sound and efficient.

Abstract: Wind power at different locations may has a significant degree of correlation. A copula function, in this paper, is employed to characterize the Joint Probability Distribution (JPD) of wind power from multiple wind farms considering their correlation. Based on this, an optimal dispatch model of power system with multiple wind farms is proposed based on Chance Constrained Programming (CCP) to describe the randomness of wind power. And a new method named Sample Average Approximation (SAA) is used to transform the chance constrians in CCP. Finally the Particle Swarm Optimization (PSO) is used to solve the dispatch model. Simulation results show the affectivity of this model and method, which will be highly useful for optimal dispatch of power system with multiple wind farms.

Abstract: In this paper, from the medi-scope point of view, the intersection parameter is classified as the section parameter, and then the new intersection traffic state coefficient is defined. Based on the reachable matrix, a new method-hierarchical intersection analysis is used to divide the intersections into different crowded levels. Next, crossroad accessibility matrix is developed to distinguish the section connectivity and get the state results of the whole network. Last, we use this method to identify congestion state of the traffic on the road around Wuchang railway station, and the outcome shows the simulation result and the practical state are consistent.

Abstract: This paper describes the implementation of semi-passive switching shunt control for electro-magneto-mechanically coupled flexible structures. This simple system consists of a permanent magnet attached to an aluminum beam and a coil placed below the magnet with a switching circuit connected to the end of the coil. The MATLAB Simulink program and dSPACE hardware were employed for realizing the switching mechanism. Switching is done between open-circuit and short-circuits states. When the structure moves away from equilibrium, the circuit is short circuited, thereby dissipating energy, subsequently the system returns back to open circuit state. This novel self-sensing electromagnetic switching damper was compared with the traditional laser-sensing method for vibration control of the structure. The results show that the proposed semi-passive switching shunt damper can be successfully applied to minimize the magnitude of vibrating flexible structures.

Abstract: Preventing high-voltage power transmission lines ice-covered is ensure to power system the important guarantee of safe and reliable operation in the extreme weather. The size of anti-ice critical current is reasonable or not will directly affect the anti-ice effect. This paper conducts a comprehensive analysis of thermal balance process of the wire surface, and proposes a critical current model to anti-ice. In this paper, the minimum melting ice current of under the ultra-thin ice cover (0.05mm) circumstance is regarded as the anti-ice currents. Finally, by the model established in this article, calculating critical current of some typical wires in Hunan electric power grid, and the result is compared with result of existing literature made the critical current model, verified accuracy of model.

Abstract: The holistic simulation study is based on multi-agents to stimulate the behavior of mobile communication. The paper intents to understand the effect of the regulation on the market of mobile communication on the methodology of complex adaptive system simulation in swarm platform. The simulation was on the condition of mimic surrounding. The simulation program includes four classes of Swarm objectives. Results reveal that reasonable, ordered and co-coordinated communication market is on the state of the regulatory of duopoly. Based on the multiple agents modeling on the platform of swarm software, we engendered an artificial mimic mobile market to imitate the mobile telecommunication market. The effect of regulatory rules can be adjusted as the time going by. The best effect appeared at the middle stage of the policy in practice.

Abstract: Factors that affect the safety of coal mine roof is a multi-faceted, information fusion technology can take full advantage of multi-source information complementary, comprehensive, and improving information quality and credibility of coal mine roof safety. In analyzing the current monitoring means, a coal mine roof safety evaluation model is presented based on information fusion, and given information processing steps of multi-sensor data analysis, processing, distribution and integration based on Dempster-Shafer evidence theory; For the elimination of multi-source data fusion of uncertain factors, proposed coal mine roof safety decision-making rules; The simulation analysis shows that the validity of the model and practicality.

Abstract: Establish the mathematical model for distillation columns running system, and calculate configurable and performance parameter. Using MATLAB to simulate and analyze dynamic external load such as wind load and earthquake load, do the curve fitting. That provides theoretic results and simulating curve for designing and modifying column structure. New dynamic continuous computation in external load is substituted for the traditional subsection computation for the first time. Numerical superposition and curve fitting of load along the entire tower is completed. That avoids discontinuous stress in the junction point generated by subsection computer with deviation value to the full. Bending moment calculated can infinitely close to the ground beyond section numbers, and describes the external load more truly and reliably. Simulation results of an actual system demonstrate that precision of continuous computation is obviously higher than that of subsection computation. Simulation software based on MATLAB has high efficiency, good stability, which is convenient to checkout columns strength, rigidity and stability under dynamic external load.