Papers by Keyword: Monte-Carlo Simulation

Abstract: Extensive simulations applying the Monte Carlo Potts model were carried out on a twodimensional square lattice to evaluate the influence of higher lattice temperatures on grain growth kinetics and the Zener limit. A wide range of simulation temperatures (KTs) were applied on a matrixof size 1000² with Q-state 64. They were then dispersed with a wide range of second-phase particles and ran to 100,000 Monte Carlo steps. The critical temperature for a square lattice with eight nearest neighbors (8 NN) was established as KTs = 0.4, after evaluating several growth parameters, undersimulated thermal conditions. Simulations were then next run to stagnation, for higher temperatures up to the critical value of KTs, and various growth parameters were computed in the pinned state. The Zener limit was found to scale with the square root of the surface fraction of second-phase particleswhile varying exponentially with its fraction lying on the grain boundaries.

Abstract: Load carrying mechanical structures like trusses face uncertainty in loading along with uncertainty in their strength due to uncertainty in the development, production and usage. The uncertainty in production of function integrated rods is investigated, which allows monitoring of load and condition variations that are present in the product in every phase of its lifetime. Due to fluctuations of the semi-finished parts, uncertainty in governing geometrical, mechanical and electrical properties such as Young's moduli, lengths and piezoelectric charge constants has to be evaluated. The authors compare the different direct methodical approaches Monte-Carlo simulation, fuzzy and interval arithmetic to describe and to evaluate this uncertainty in the development phase of a simplified, linear mathematical model of a sensory rod in a consistent way. The criterion to compare the methodical approaches for uncertainty analysis is the uncertain mechanical-electrical transmission behavior of the sensory rod, which defines the sensitivity of the sensory compound.

Abstract: In the assessment of internal ballistic performance reliability of Solid Rocket Motor (SRM), eigenvalue discriminance method has long been used. In order to avoid the limitations of the traditional methods, a curve similarity discriminance modification combined with Hausdorff Distance was introduced. A Monte-Carlo simulation model of internal ballistic performance was established, and several uncertain parameters were chosen. A sample analysis of performance reliability of a designed SRM was presented. The result was credible, which proved the modification is feasible and it can meet the needs of the assessment of the internal ballistic performance reliability.

Abstract: The thermodynamic properties of a ferrofluid modeled by a bidisperse system of dipolar hard spheres in the absence of external magnetic field are investigated using theory and simulations. The theory is based on the virial expansion of the Helmholtz free energy in terms of particle volume concentration. Comparison between the theoretical predictions and simulation data shows a great agreement of the results.

Abstract: An influence of quenched nonmagnetic disorder on the phase transitions in the two dimensional antiferromagnetic Potts model with a number of spin state q=3 on a triangular lattice is calculated by the Monte-Carlo method. The systems with linear sizes L=20÷144 at spin concentrations p=1.00, 0.90, 0.80 are studied. By means of the fourth order Binder cumulant method, the inclusion of a quenched disorder as nonmagnetic impurities into a pure antiferromagnetic Potts model is shown to be the cause of the change of the first order phase transition into the second one.

Abstract: The message transmission reliability is very important for the design of the CAN (Controller Area Network) bus system, which is related to the normal operation of the bus control system. The bus message transmission time parameters are analyzed based on the CAN bus scheduling theory. The formula is a derived by means of probability analysis based on the fourth-moment method. An example is calculated to get its message reliability and the result is contrasted with the MONTE-CARLO method simulation, and then the bus message transmission reliability can be got. It has great practical significance.

Abstract: Large-scale wind farms connected into main grid is accompanied by the reducing of the stability, reliability and security of the power system operation. So the risk cost becomes one of the important factors influencing the profit of transmission network expansion planning. This paper adopted the method of clustering wind power transmission. The objective function established in this paper reflecting the comprehensive benefits of transmission project defined the P_line (transmission capacity) as variable. In order to maximize the comprehensive benefits of the transmission project, the influence of transmission constructing cost, the congestion loss probably caused by a low transmission capacity as well as the cost of risk were taken into account. Calculation of risk is a very complex mixed integer nonlinear problem, so we used Monte-Carlo Simulation to solve this question. Example shoes that the proposed method can achieve optimal transmission capacity, transmission project benefit and planning.

Abstract: . This article is based on the concept of vulnerability for power system, and focuses on vulnerable source of distribution network and summarizes the characteristics of vulnerability assessment methodologies and inadequate for the distribution network.And pointed out that domestic and international research for distribution network vulnerability is still in the initial stages,evaluation of existing methods are accessible only from one side distribution system's security status,the vulnerability assessment methodology of distribution network can be more fully reflected the global distribution network of security that will be researched in the future.

Abstract: This paper presents an iterative power system balance reliability calculating technique ensuring better convergence and faster calculations. The technique is called "supplied demand". Nodal power imbalance is considered as the primary stochastic value under analysis. An analytical solution does not contain probability density functions. It results in faster calculations. Results were verified by Monte Carlo Simulation and showed high accuracy of the technique.

Abstract: Because wind energy fluctuates randomly, the output power of wind turbine generators is uncertain. The reliability of power systems including wind generation is analyzed in this paper. In this paper, the reliability model of wind generators and the model of transmission network are combined by considering the sequential and autocorrelation of wind speed, the output power function and the forced outage of wind units. Then a reliability evaluation model of generation and transmission system, in which the system security constraints are satisfied, is built and the objective function is LSC. Taking IEEE-RTS96 system as an example, the reliability index which can reflect the effects of wind farms is calculated. The result provides the scientific reference for connecting wind farms to power systems.