In order to improve the efficiency of data distributed management service in distributed interactive simulation based on high level architecture (HLA) and to reduce the network traffic and save the system resource, th...In order to improve the efficiency of data distributed management service in distributed interactive simulation based on high level architecture (HLA) and to reduce the network traffic and save the system resource, the approaches of multicast grouping in HLA-based distributed interactive simulation are discussed. Then a new dynamic multicast grouping approach is proposed. This approach is based on the current publication and subscription region in the process of simulation. The results of simulation experiment show that this approach can significantly reduce the message overhead and use fewer multicast groups.展开更多
The development process as well as the core theory of distributed interactive simulation and high level architecture are discussed, and combined with graphics features, a system of real time distributed visual simula...The development process as well as the core theory of distributed interactive simulation and high level architecture are discussed, and combined with graphics features, a system of real time distributed visual simulation is established. Based on computer network, simulation platform is built by installing related software and modeling object, and the interactive functions are extended by programming. A set of solutions for building a distributed visual simulation system that include both hardware and software are put forward, and a practical instance is also provided. The whole building process can be summarized into two steps that are scheme consideration and system realization.展开更多
The effect of particle size distribution on the field and temperature dependence of the hysteresis loop features like coercivity（HC）, remanence（MR）, and blocking temperature（TB） is simulated for an ensemble of s...The effect of particle size distribution on the field and temperature dependence of the hysteresis loop features like coercivity（HC）, remanence（MR）, and blocking temperature（TB） is simulated for an ensemble of single domain ferromagnetic nanoparticles with uniaxial anisotropy. Our simulations are based on the two-state model for T 〈 TB and the metropolis Monte-Carlo method for T 〉 TB. It is found that the increase in the grain size significantly enhances HC and TB. The presence of interparticle exchange interaction in the system suppresses HC but causes MRto significantly increase.Our results show that the parameters associated with the particle size distribution（D（d,δ）） such as the mean particle size d and standard-deviation δ play key roles in the magnetic behavior of the system.展开更多
The characteristics of a torpedo＇s acoustic homing trajectory with multiple targets were studied. The differential equations of torpedo motion were presented based on hydrodynamics. The Fourth order Runge-Kutta metho...The characteristics of a torpedo＇s acoustic homing trajectory with multiple targets were studied. The differential equations of torpedo motion were presented based on hydrodynamics. The Fourth order Runge-Kutta method was used to solve these equations. Derived from sonar equations and Snell＇ s law, a simple virtual underwater acoustic environment was established for simulating the torpedo homing process. The Newton iteration method was used to calculate homing range and ray tracing was approximated by pieccwise line, which takes into consideration distortions cause by temperature, pressure, and salinity in a given sea area. The influence of some acoustic warfare equipment disturb the torpedo homing process in certain circumstances, including decoys and jammers, was alsotaken into account in simulations. Relative target identification logic and homing control laws were presented. Equal consideration during research was given to the requirements of rcal-timeactivity as well as accuracy. Finally, a practical torpedo homing trajectory simulation program was developed and applied to certain projects.展开更多
文摘In order to improve the efficiency of data distributed management service in distributed interactive simulation based on high level architecture (HLA) and to reduce the network traffic and save the system resource, the approaches of multicast grouping in HLA-based distributed interactive simulation are discussed. Then a new dynamic multicast grouping approach is proposed. This approach is based on the current publication and subscription region in the process of simulation. The results of simulation experiment show that this approach can significantly reduce the message overhead and use fewer multicast groups.
文摘The development process as well as the core theory of distributed interactive simulation and high level architecture are discussed, and combined with graphics features, a system of real time distributed visual simulation is established. Based on computer network, simulation platform is built by installing related software and modeling object, and the interactive functions are extended by programming. A set of solutions for building a distributed visual simulation system that include both hardware and software are put forward, and a practical instance is also provided. The whole building process can be summarized into two steps that are scheme consideration and system realization.
文摘The effect of particle size distribution on the field and temperature dependence of the hysteresis loop features like coercivity（HC）, remanence（MR）, and blocking temperature（TB） is simulated for an ensemble of single domain ferromagnetic nanoparticles with uniaxial anisotropy. Our simulations are based on the two-state model for T 〈 TB and the metropolis Monte-Carlo method for T 〉 TB. It is found that the increase in the grain size significantly enhances HC and TB. The presence of interparticle exchange interaction in the system suppresses HC but causes MRto significantly increase.Our results show that the parameters associated with the particle size distribution（D（d,δ）） such as the mean particle size d and standard-deviation δ play key roles in the magnetic behavior of the system.
文摘The characteristics of a torpedo＇s acoustic homing trajectory with multiple targets were studied. The differential equations of torpedo motion were presented based on hydrodynamics. The Fourth order Runge-Kutta method was used to solve these equations. Derived from sonar equations and Snell＇ s law, a simple virtual underwater acoustic environment was established for simulating the torpedo homing process. The Newton iteration method was used to calculate homing range and ray tracing was approximated by pieccwise line, which takes into consideration distortions cause by temperature, pressure, and salinity in a given sea area. The influence of some acoustic warfare equipment disturb the torpedo homing process in certain circumstances, including decoys and jammers, was alsotaken into account in simulations. Relative target identification logic and homing control laws were presented. Equal consideration during research was given to the requirements of rcal-timeactivity as well as accuracy. Finally, a practical torpedo homing trajectory simulation program was developed and applied to certain projects.
