Applied Mechanics and Materials Vols. 204-208

Abstract: using the FLUENT software, this paper taking the current code for the design of building structures as the comparison standard, have numerical wind tunnel simulation of the wind the surface wind pressure on arch roof. It focuses on the analysis of the effects of three kinds of pressure velocity coupling algorithm on the numerical simulation results, respectively SIMPLE, SIMPLEC, PISO, to provide a basis for the reasonable selection of algorithm.

Abstract: Using the FLUENT software, this paper taking the current code for the design of building structures as the comparison standard, have numerical wind tunnel simulation of the wind the surface wind pressure on low layer double slope roof. It focuses on the analysis of the effects of turbulence model selection on the numerical simulation results, such as Spalart-Allmaras、Standard k −ε、RNG k −ε、Realizable k −ε、Standard k −ω、SST k −ω and RSM, to provide a basis for the reasonable selection of turbulence models.

Abstract: Take generator system included AVR (automatic voltage regulator) and PSS (power system stabilizer) as an example, Using the time simulation method, Study the equivalence between the transfer function model and the equivalent circuit simulation, and establish the corresponding relations between the circuit structures, internal parameters and transfer function parameters, based on the energy of equivalent circuit, the Hamiltonian function of transfer function is derived indirectly, and the Hamiltonian model is established. The study in this paper provides a new way to establish generalized Hamiltonian model for linear system based on transfer function.

Abstract: Using the weighted inverse theory of matrices and the weighed inverse topological change method of finite element structures, a set of formulae used in the sensitivity analysis of the parameters of a structure are presented. Combined with the previous work of the author, it can analyze the static modification of the structures efficiently. The all formulae of this method are explicit ones and have advantages of simplicity and easily operation on the computer. An example is given to demonstrate the valid and the efficiency of the formulae.

Abstract: This paper makes use of knowledge granular to present a new method to mine rules based on granule. First, use the measure to measure the importance of attribute, and get the granularity of the universe, and then repeat this procedure to every granule of the granularity, until the decision attribute has only one value for all granules, then we will describe every granule to get the rule. The analysis of the algorithm and the experiment show that the method presented is effective and reliable.Classification rules is the main target of association rule,decision tree and rough sets.a new algorithm to mine classification rules based on the importance of attribute value supported.this algorithm views the importance as the number of tuple pair that can be discernible by it,and the rules obtained from the constructed decision tree is equivalent to those obtained from ID3,which can be proved by the idea of rule fusion.however, this method is of low computation,and is more suitable to large database . rough sets is a techniques applied to data mining problems. This paper presents a new method to extract efficiently classification rules from decision table. The new model uses rough set theory to help in decreasing the computational effort needed for building decision tree by using what is called reduct algorithm and a rules set (knowledge) is generated from the decision table. reliable classifier architecture is obtained and its effectiveness is verified by the experiments comparing with traditional rough set approaches. Data mining research has made much effort to apply various mining algorithms efficiently on large databases.

Abstract: When applied to Multi-Objective Decision Making (MODM), genetic algorithm is plagued with two problems: how to appreciate non-inferior solutions and how to store them. Using Borda number as the fitness of a chromosome, an advanced Multi-Objective Genetic Algorithm ( MOGA) is provided in this paper, which can solve these problems in an easier way; and with the characteristic of Genetic Algorithm (GA) of producing a number of feasible solutions, this approach is able to obtain the set of non-inferior solutions without information of the decision-maker’s preferences. Finally, a simulated example to apply this algorithm to a multipurpose reservoir’s operation is provided, indicating the feasibility and effectiveness of this advanced MOGA.

Abstract: In order to reduce screen plugging and screen pasting, improve the efficiency of screening, a kind of dual-frequency vibrating screen was introduced. It had been used three exciting motors. We established the mechanical model of this vibrating screen, and used Matlab-simulink software to analyze the trajectory changes of screen surface, influenced by mass moment rate, initial phase differences and installation position between high and low frequency exciting motors. The results of the study indicate that, the rate of mass moment and difference of initial phase angle have great influence on the motion trail pattern and amplitude of vibration of the screen, and the installation position of high-frequency exciting motor have less influence on screen surface trajectory under the condition of exciting motors’ parameters given in this article. When designing dual-frequency vibrating screen, we can use the method of this paper to select appropriate rate of mass moment, difference of initial phase angle and so on, and achieve the expected motion trajectory of vibrating screen.

Abstract: With the development of network and information technology, it is highly desirable to create 3D geoscience applications in the network environment. However, construction of web-based 3D terrain model is one of the foundation works of 3D geoscience applications in the network environment. This paper presents a new method of constructing large-scale 3D terrain model based on Extensible 3D (X3D). In this way, we first use Geospatial components of X3D to build 3D terrain model by using DEM as the data source, then we publish the 3D terrain model to the internet with a architecture of Brower/Server and plug-in technology. To promote the display performance of large-scale 3D terrain model, We presents an approach that using the Level of Detail (LOD) technology to simplify the 3D terrain model. The application results show that the method this paper presented has advantage of easy to integrate with other network system, thereby easy to realize data sharing and interoperation; the method also has virtues of fast display speed, high ability of interaction. It’s an effective method for constructing large-scale 3D terrain model in network environment.

Abstract: A Web information retrieval algorithm based on Web page segment is designed, the key idea of which is to segment each Web page into different topic areas or segments according to its HTML tags and contents since Web pages are semi-structure. First, the algorithm builds a HTML tag tree, and then it combines nodes in the tree under the rule of content similarity and visual similarity. During the process of retrieval and ranking, the algorithm makes full use of the segmentation information to sequence the relevant pages. The experimental results show that this method is able to improve the precision in search significantly and it is also a good reference for the design of the future search engines.

Abstract: In the situation that unit failure probability is imprecise when calculation the failure probability of system, classical probability method is not applicable, and the analysis result of interval method is coarse. To calculate the reliability of series and parallel systems in above situation, D-S evidence theory was used to represent the unit failure probability. Multi-sources information was fused, and belief and plausibility function were used to calculate the reliability of series and parallel systems by evidential reasoning. By this mean, lower and upper bounds of probability distribution of system failure probability were obtained. Simulation result shows that the proposed method is preferable to deal with the imprecise probability in reliability calculation, and can get additional information when compare with interval analysis method.