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Abstract: A detailed mathematical simulation and experimental investigation of airflow in solar chimneys is studied in this paper. Several experimental studies were carried out on the solar chimney; their choice depends on the parameter of the design and the thermal performances for different geometrical configurations. The experimental tests show that the field speeds in the chimney is influenced by the width of the channel and also of the angle of inclination of the chimney. Therefore, investigations have been carried out in this paper to find the effect of inclination on the performance of solar chimney in Ouargla Province, Algeria. The simulation of this problem is implemented into the commercial CFD code Fluent 6.3. 26. The conservation equations of mass, continuity and energy are solved by the Finite Volume Method. The validation of the results is presented. An good agreement between the experimental results and simulation ones is observed. [Copyright &y& Elsevier]

Abstract: This paper uses Diffuser Augmented Wind Turbine for reference. According to the characteristics of ocean current movement, this paper gives several dome model programs for the straight blade vertical-axis tidal turbine. Make use of it to increase its output power. This paper gives several dome model programs for the straight blade vertical-axis tidal turbine. And optimum scheme is chosen by numerical simulation. [Copyright &y& Elsevier]

Abstract: The paper adopts standard k−ɛ turbulence model and other mathematical models, and completing the blending lignite combustion numerical simulation of 600 MW boiler of one power plant. Three conditions were simulated in this paper, and these three conditions were compared and analyzed, the basic conclusion is consistent with the test. The result shows that the combustion character of blending lignite is lower than burning soft coal. Burning lignite shows a decline furnace temperature, and the simulation results are consistent with the experimental results. Pay attention to adjust the reasonable operating manner, and the operation is safety and economic. At the same time this paper also provides a useful reference for researching tangentially fired boiler furnace process. [Copyright &y& Elsevier]

Abstract: A large AC generator is an important component of the power system. Researches on the AC generator relaying for the next-generation ECMS and an efficient operation of protection control system are necessary. These require developments on detailed generator modeling and internal fault analysis, and prototyping for multifunctional IED device dedicated to next-generation production. In this paper, over-excitation relaying algorithm is one of the main protection elements which have an important role in DGPS(Digital Generator Protection System), was proposed. This paper first briefly introduces a principles of over-excitation and DFT-based gain compensation algorithm was adopted for the frequency measurement. Subsequently, protection scheme of over-excitation was presented. The 765[kV] modeling data of South Korea using EMTP-RV was used for simulations. The simulation result of over-excitation relaying are also provided. [Copyright &y& Elsevier]

Abstract: The numerical modeling of High Temperature Air Combustion (HTAC) could correctly predict the flame and emission characteristics so far, however, the precision is not satisfactory. In this paper, a parameter-modified Eddy-Break-Up (EBU) model with a three-step reaction scheme was used to simulate the HTAC process in a furnace of 2m ×2m×6.25m. Reynolds stress model (RSM) is used for the computational fluid dynamics (CFD) simulation. Comparison between experimental data from published papers, the original and modified EBU combustion models demonstrates that a smaller coefficient ‘A’ in the volumetric fuel consumption rate of the EBU model could improve the modelling precision. When ‘A’ is modified to be 1 other than its original value, 4, in the EBU model, the modeling could give improved results of the local distribution of CH4, temperature and NO emission. [Copyright &y& Elsevier]

Abstract: This paper studies the vehicle rollover warning based on the vehicle running state parameters which are easy for collecting. By taking advantages of neural network and support vector machine, this paper analyzes the probabilities of the vehicle rollover in the scenario of single lane change and establishes a warning model which could predict the rollover 0.4seconds in advance for a particular type of vehicle. According to the validation experiments on Ve- DYNA which is a vehicle dynamic simulation software, the results validate the warning model''s good performance with the maximum error as 0.04 second and no missing cases which indicates its validity for rollover warning. [Copyright &y& Elsevier]

Abstract: In the present paper, a new CA-based model considering the following car horning is established and is analyzed in great detail. Firstly, how the following car horning can influence the traffic system is discussed. Secondly, by applying the cross-covariance method, proper parameters are indicated to explore the phase transition features of the model. The results show that the model proposed in this paper can simulate complex and realistic traffic phenomena. [Copyright &y& Elsevier]

Abstract: This paper discusses the modeling and control of Voltage Source Converter High Voltage Direct Current (VSC HVDC) systems in a multi-terminal configuration (MTDC). Both steady-state interactions, as well as transient stability modeling and control are addressed. Simulation results show that adequately modelling the DC voltage droop characteristics or a distributed voltage control in both the power flow algorithm and in the transient stability models allows to simulate the steady-state results of the dynamic simulation by means of power flow software algorithms. [Copyright &y& Elsevier]

Abstract: Based on finite element theory, using FLUENT software and three-dimensional model to simulate liquid metal free surface and temperature field of casting filling process numerically. Boundary and initial conditions, such as velocity, pressure, temperature, etc., was reasonably set. The feasibility of using FLUENT to simulate three-dimensional casting was studied; the fluctuation of molten metal free surface was observed; the temperature distribution data on the end of filling was recorded, for further numerical simulation of casting solidification process which provided an accurate initial condition. This paper also predicted defects on casting filling process, and provided a basis for process optimization. [Copyright &y& Elsevier]

Abstract: In order to handle the situation of power system grounding fault better, this paper built the mathematical model of power system resonance grounding fault based on the resonance grounding principle. And simulated the resonance processes by using MATLAB/SIMULINK/ SIMPOWERSYSTEM (SPS) software. The obtained results show that there will appear zero sequence current at each point of power system when the grounding faults occurrs. And if the circuit has the point of biggest amplitude of zero sequence current, then it is just the fault phases. The simulation data further verified that arc suppression coil grounding could directly decreases the grounding current when the single-phase grounding fault occurred. Moreover, it effectively eliminates the arc from the process and becomes the more reasonable grounding mode. [Copyright &y& Elsevier]

Abstract: This paper introduces membership cloud function and membership cloud generator, then establishes membership cloud function model which is fit for mine. With the application of the model through simulation, the reliability of ring network, tree network and star network in mine is analyzed. We could know that ring network which has the maximum reliability but poor fault resistance ability costs for not all links and nodes could use double road and it is not suitable for mine roadway. Tree network and star network, whose reliability are poor than double ring network''s, are more suitable for mine roadway and have high cost performance, so they are more suitable for application in mine. [Copyright &y& Elsevier]

Abstract: In order to control the position of hybrid stepper motor and improve its performance, direct torque control strategy is adopted. The main idea of this paper is to present the implementation of an emotional controller for position control of hybrid stepper motor drive. The proposed controller is called Brain Emotional Learning Based Intelligent Controller (BELBIC). This controller is a computational model of emotional processing mechanism in the brain. The effectiveness of the proposed BELBIC controller-based hybrid stepper motor drive is verified by simulation results. [Copyright &y& Elsevier]

Abstract: In classical methods only average torque of the stepper motors is controlled which causes high speed and torque ripple. In order to control the torque instantaneously and improve the performance of the hybrid stepper motor, direct torque control strategy is used in this paper. Then by taking model reference adaptive system scheme, which uses the hybrid stepper motor itself as the reference model, speed of the motor is estimated. The sensorless control of hybrid stepper motor based on MRAS is built and simulated with Matlab software. The results show that this control technology is simple and effective and accuracy of the estimation is considerably high. [Copyright &y& Elsevier]

Abstract: In this paper a fuzzy based dimmer circuit model for daylight harvesting is proposed. The model incorporates the variable daylight intensity and number of occupants in a room. The dimmer circuit controls the switching ON and OFF of LEDs (light emitting diode) in a room corresponding the daylight intensity and occupants while the required level of illumination is maintained. The uncertainty in input variables is incorporated in the model with the fuzzy logic. The developed model is simulated in MATLAB and LABVIEW environment. The developed model is tested for different situations. [Copyright &y& Elsevier]

Abstract: In view of hierarchy and grade characteristics in the military organization, the paper studied the CABC (Combat Agent Based Command) organization model according to the organizational view of multi-Agent system. Through building the model, it reflected the organization structure, the organization state of the combat unit and the relationships between units the same as true combat background, which can adapt to combat simulation needs better. By comparing with model experiments, it has obvious advantages in time-cost when the amount of individual is small. [Copyright &y& Elsevier]

Abstract: Messaging system can be treated as a collection of message channels, ending points, messaging routers, and process management. For a particular application, the implementation style of the underlying messaging system is not unique. However, different approach results in various performance and resource requirements. In this paper, a testing environment is designed to investigate the performance and resource requirements features of various implementation techniques of a message system. The alternative implementation of the message channel, endpoint, routing and process management is organized with the concepts of logical topologies, which present the integration style of a messaging system. The testing experiments are carried along three different topologies: the business process management pipeline, the enterprise service bus, and enterprise service network. The pseudo web service clients and web service providers is implemented to simulate the workload effects of a real environment. From the detailed analysis of the testing results, it is validated that the ESB model provides the most flexible message delivering service with the cost of largest transaction throughput, but consumes the smallest of processor usage and memory occupation. [Copyright &y& Elsevier]

Abstract: Dynamic trustiness evaluation of software has become a hot issue in information security field. In order to improve the accuracy of evaluation, a Trustiness Evaluation Model Based on Software Behavior (TEMSB) is proposed in this paper. TEMSB introduces Software Behavior Trace (SBT) to describe software behavior. SBT consists of operation trace, which is composed by operation sequences of the running software, and function trace depicted by a series of scenes. With the purpose of reducing time and space overheads of trustiness evaluation, we present reduction rules for SBT. In our model, we apply identification evaluation rule and scene evaluation rules to check the practical behavior of software. In particular, we consider a kind of special check points, named as branch points, at which we determine branch directions through scene information. The simulation results indicate the precision and efficiency of TEMSB. [Copyright &y& Elsevier]

Abstract: When sailing in seawater, the forces exerted to torpedo are complicated and can’t be precisely measured, especially the hydrodynamic parameters. So it is very important to establish non-linear mathematics models of torpedo moving characteristics in torpedo weapon development course. Firstly, according to torpedo underwater motion characteristics, this paper analyzes all kinds of forces and moments exerted to torpedo. Then based on momentum theorem and momentum moment theorem, torpedo spatial motion dynamic equations are established. Combining with torpedo kinematic equations and control system equations, simulation program written by standard C language are compiled and carried out successfully in Visual C++ 6.0 compilation environments. Finally several typical simulation figures and analysis are presented. Simulation results show that torpedo spatial motion mathematics models are accord with torpedo motion characteristics in real voyage course, having better usability and expansibility, and can satisfy the design need preferably. [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: In order to study the satellite''s moving features and the size of stable reigns around the center equilibrium points of asteroid, 1:1 resonant orbits theory are applied in this paper. First the Hamilton function described by Delaunay variable is simplified to Schubart standard. Secondly the simplified mathematical model is used to discuss the form of orbital motion, vibration period of satellites which locate orbit the asteroid''s equilibrium points and the relationship between each other. And then Asteroid Vesta is taken as a simulation example to verify the correctness of these conclusions above. Finally, exploiting the properties of energy integral of Schubart standard, the formula of deducing the radius of stable region around the center points is given, which is also applied to analyze the properties of orbital motions both inside and outside of the stable region. The research in this article not only can help us better understand the equilibrium points of asteroids and the dynamical environments in the vicinity of which but also can it supply theoretical basis in designing the orbit around the equilibrium points around the asteroid. [Copyright &y& Elsevier]

Abstract: This paper proposed a software solution of GPS receiver quality inspection system based on the Simulated Signal Source. The GPS receiver quality inspection software of friendly man-machine interface, high efficiency and good stability is developed using language C#. Firstly, the functions of system are analyzed by the objective-oriented means. And the block diagram of whole software structure is given. Then the main function, data flow diagram, design effect and testing process of the Mathematical and Simulation Subsystem, Management and Control Subsystem and Testing and Evaluation Subsystem are detailed introduced. At last the quality inspection report on the Novatel dual-frequency receiver proved that the GPS receiver quality inspection software system is of good openness and high transplant ability. [Copyright &y& Elsevier]

Abstract: Heat pump systems can be found in high number of applications. One of these is the production of domestic hot water. This paper presents a quasi-steady state simulation model to predict the performance of a simple air source heat pump water heater (ASHPWH). The mathematical model consists of submodels of the basic system components, namely, evaporator, condenser, compressor, and expansion valve. These submodels were built based on fundamental principles of heat transfer and thermodynamics. The model was coded into MATLAB software and used to predict system parameters of interest such as hot water temperature, evaporating and condensing pressures, heat rejected in the condenser, electric power input, heating seasonal performance factor, and coefficient of performance. [Copyright &y& Elsevier]

Abstract: Based on gray error GM (1,1) model, the paper proposed an improved error GM (1,1) model, and used this model to predict cultivated land in Yiyang. The results show that the improved error GM (1,1) model has high prediction accuracy, and better simulation results. And the results conform to the cultivated quantity change rule of Yiyang City, that is, the land area of Yiyang City, will appear in the next few years, modest growth trend, but the per capita arable land is still in the alert level of the United Nations. Therefore, protection of cultivated resources, rational utilization and protection of arable land are urgent tasks. [Copyright &y& Elsevier]