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Abstract: By the use of modelling software, this paper set up the three-dimensional physical model of single-stage turbine and guided it into the pre-process software. After meshing the turbine flow channel, simulating the mud flow characteristics in Turbine with CFD, and calculating the pressure drawdown at the inlet/outlet and the pressure distributions in single-stage turbine. Such results indicate that the pressure drawdown of single-stage turbine is influenced by the mud discharge capacity, drilling fluid density and viscosity. The pressure drop increases with the augment of mud discharge, which is approximately linear. There are significantly positive correlations between the pressure drawdown and the increase of mud density. The research in the paper provides reliable guidance in turbine flow channel design and the drilling technological parameters optimizing. [Copyright &y& Elsevier]

Abstract: Multi-beam bathymetry sonar is one of the current important equipments for seafloor bathymetry information detection. This paper extends the phase center cross-correlation method (PCCCT) which is successfully used in a 3- row bathymetric sidescan sonar to multi-beam bathymetry sonar, and a 3-subarray Direction-of-Arrival (DOA) estimation method based on phase difference measurement is proposed. A comparison with the split-beam DOA estimation method which is commonly used in multi-beam bathymetry sonar is employed. The paper analyzes the basic principle of the new method in details, and derives its mathematical model expression. The performance analysis is accomplished in theory. Computer simulation data is processed, and the results show that the 3-subarray DOA estimation method is effective and practical for multi-beam bathymetry sonar. [Copyright &y& Elsevier]

Abstract: The development of China''s animation should take some excellent artistic forms of our nation into consideration, only those animation works with national characteristics are precious. The designer should comprehend the essence of traditional cultures, combine the traditional artistic elements on modeling and can recreate. This paper creates animation images with Chinese culture characteristics through analyzing the Chu art characteristics and taking them as artistic reference of animation modeling. Its application in the FLASH software and some noticeable problems are considered; and the animation modeling has unique artistic charms and values. [Copyright &y& Elsevier]

Abstract: In this paper three-dimensional mathematical model of gas-solid two-phase in a radial style diesel particulate filter (DPF) is established and flow computation software was used to simulating distribution characteristics of gas-solid two-phase and particle distribution uniformity. Several influence parameters such as flow velocity, divergence angle and particle diameter was investigated. Through the verification analysis, the simulation calculation results can reflect the laws of gas-solid two-phase flow inside this DPF .The results indicate that distribution uniformity of particle could be improved by reducing inlet velocity, divergence angle and particle diameter. The study is useful for structural parameters optimization designing and controlling particle regeneration of radial style diesel particulate filter. [Copyright &y& Elsevier]

Abstract: In distribution system planning with photovoltaic generations (PVGs), if load is not properly modeled in the simulation, the accuracy of results will be affected. A large number of studies show that load characteristics play a impotrant role in the system analysis. This paper presented the resultant load model, and on this basis, studied the impacts of the constant power load model and constant impedance load model on PV generation planning. Simulation results show that the selection of load models has an important impact on PV generation planning. [Copyright &y& Elsevier]

Abstract: This paper presents a three-phase STATic synchronous COMpensator (STATCOM) based on a current source inverter. Instead of the typical three-phase current bridge inverter it is used a power converter topology with only a single-phase current bridge inverter. A dynamic model of the STATCOM in αβ coordinates is used as a basis for control design. The control system uses a cascade structure where a fast ac current inner loop and a slow dc current control outer loop is used. For the inner loop, is used a sliding mode technique to generate αβ space-vector modulation. This fast and robust controller the ac currents of the STATCOM are actively shaped, being possible to maintain the desired currents even with high ripple DC inductor current. For the outer loop, is used a PI controller. Computer simulations are presented allowing validating the proposed STATCOM and their control system. [Copyright &y& Elsevier]

Abstract: This paper is concerned with the description and verification of an energy model of a building using the BSim software. The aim is to determine the effect of the basic heat gains on the energy consumption of a building. Simulations were performed on the basis of the actual hourly-interval climatic data over a whole year. It has been found, that the highest heat gain comes from solar radiation. [Copyright &y& Elsevier]

Abstract: This paper introduces a scheme of differential geometry and model reference adaptive theory to solve the nonlinear decoupling control problem while the machine parameters vary. As a result, two dynamical decoupled two-order subsystems between flux and speed are deduced. Simulation experiments prove the correctness about the theories and analysis. [Copyright &y& Elsevier]

Abstract: As a modeling tool, Petri net has been widely used. However graphic Petri nets can give the visual description, but not simulate execution process and automatically generate reachability graph. Maria is an effective and comprehensive analyzer for P/T Nets. It can complete dynamic analysis of Petri nets. In this paper, the structure and relationship of graphic Petri nets and Maria modeling language are discussed in detail. On this basis, a conversion algorithm from graphic Petri nets to description with Maria modeling language is presented. Finally, the functional modules of graphic Petri nets analyzer based on Maria are designed and introduced. This analyzer offers a convenient way for analyzing a Petri net model by Maria. [Copyright &y& Elsevier]

Abstract: The paper presents a new intrusion detection model combining misuse detection and anomaly detection mode, and makes a research into the key technology of the model based on data mining theory. In the model, the association rules data mining algorithm is applied to establish abnormal behavior rule set for misuse detection to detect known intrusion rapidly. And the minimum dissimilarity clustering analysis algorithm is used to establish normal behavior rule set for anomaly detection to detect new unknown intrusion. Research of the model of intrusion detection based on data mining is made on KDD99 dataset. The experiment shows that the new model can improve true positives, decrease false positives and detect new intrusions. [Copyright &y& Elsevier]

Abstract: The mainly purpose of this paper is to simulate the charging and discharging process of internal melt ice-on-coil thermal storage system based on the exited experiment. Its mathematic model is built and the results of the simulation and experiment are compared for verifying the simulation. The further analysis about the influence of whole ice storage and melt process is made from thermal resistance, diameter and pipe material. Analysis indicates that making diameter larger can make heat transfer better. Larger the heat transfer coefficient of the pipe can improve thermal efficiency, but the heat resistance will not be reduced obviously as the coefficient increase. [Copyright &y& Elsevier]

Abstract: The conceptual model''s reuse is a problem in simulation system''s development. In this paper, a conceptual model development method which supports reuse is given. The method centers about task, and generalizes the conceptual model development process to the following three steps: describing system structure and its implementation procedure, decomposing task and modeling behavior. After analyzing the method''s reusability, its good impact for raising the model''s reusability can be proved. Thereby, the method can be applied in the conceptual model''s development of simulation system [Copyright &y& Elsevier]

Abstract: Activated sludge plays a very important position in biological wastewater treatment process, mathematical models and computer technology have been applied in activated sludge process widely. After fitting the experimental data and developing microbial growth kinetics model, the identification model based on biological wastewater treatment process characteristics became hot topic. This changed activated sludge process design into research of the dynamics activated sludge process for the target of high efficiency of low-power. Then, corresponding activated sludge process commercial software was developed. The first activated sludge process software based on ASM1 model, SSSP (simulation of single sludge process), was developed in 1988. With the modeling advanced development, various activated sludge process commercial software were developed, such as EFOR, STOAT, SASS PRo, DSP and GPS-X. In this paper the activated sludge software are introduced and some advises are proposed. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a Micro-modeling approach for pedestrian dynamics, which based on the agent technology. For this model, a computer program is developed to simulate and analyze evacuation phenomenon in sports stadium. Firstly, researches have analyzed the modeling method of agent and environment; the evacuation used the method of gird generation in venues and building individual decision-making model by agent. Secondly, we mainly study the behavior of sub-group, in order to reproduce the behavior, three cases have been studied to analyze the impact of evacuation. Simulation processes and results display that the model is very close to real movements of people. Therefore, this model can be used for the design of sports stadium and as the basis of command plans. [Copyright &y& Elsevier]

Abstract: In this paper, four-wheel steering and direct yaw-moment integrated fuzzy controller is designed. To verify the effectiveness of the integrated fuzzy controller, a nonlinear three-degree-of-freedom model is employed for computer simulation. Considering the nonlinear effects of tyre, Pacejka tyre model was adopted to set up the nonlinear vehicle dynamic model. Simulation on the nonlinear vehicle with integrated controller in Matlab/Simulink software environment was described for a step input. The simulations suggest, compared with FWS and 4WS, the integrated controller can make the handling and stability performance on big lateral acceleration and slip angle improved, and make the driver drive the vehicle normally. The conclusion can be useful for the system design of vehicle stability control system. [Copyright &y& Elsevier]