Reseatch of a Distributed Environmnet for Numerical Simulation in Theoretical Astrophysics

近年来，由于数字技术的飞速发展，人们获得了大量精美的天体图像。为了了解这些物体中发生了什么样的现象，迫切需要根据物理学的基本定律进行数值模拟。观测图像越精细，数值计算所需的内存越大，计算速度越快。然而，一个人需要工作站来利用如此庞大的超级计算机系统。这种技术的最新发展给了我们如此快的小型计算机。在本研究中，阐明了我们周围的小型计算机如何有效地进行理论天体物理学中的数值模拟，特别是在计算机通过通用计算机网络连接的分布式环境中。明确了在这种分布式计算环境中，专用计算机作为计算服务器的有效性。首先，详细介绍了1996年1月在天文数据分析中心安装的向量化并行中央处理器超级计算机系统。该系统作为一个分布式计算系统进行了分析和评价，该系统在处理天文学理论数值模拟方面非常有效。与大量的主内存相比，高性能存储的数量相当少，最大使用量约为30GB。并对宇宙流体力学计算专用计算机进行了评述。在流体力学计算和辐射传递计算中都找到了一种新的利用这种专用计算机的算法。通过上述研究，明确了从工作站到高端计算机服务器的系统操作系统。未来需要明确天体物理数值模拟应该准备什么样的用户环境，也需要找出适合天文计算的计算机体系结构和操作系统。少

Due to a gross development in digital technolygies, there have been obtained many and fine images of astronomical objects, recently. In order to understand what kind of phenomenon occurs in those objects, it is strongly required to carry out numerical simulations based ot basic laws in physics. The finer the observational images, the larger the size of memory and faster computation required for the numerical computations. While, one needs workstations to utilize such a large supercomputer system. Recent development in such technology gives us so fast small computers.In this research, it is clarified that how those small computers around us can be effective in poroceeding numerical simulations in theoretical astrophysics, especially in a distributed environment in which computers are connected through general purpose computer network. It is also clarified that special purpose computers are effective as computation servers in this distributed computaional environment.First, a detailed in … More vestigation on the supercomputer system with vectorized-parrallel CPU's which has been installed at the Astronomical Data Analysis Center, NAOJ,in january 1996. This system is analyzed and evaluated as a distributed computing system, and the system is very effective for processing theoretical numerical simulations in astronomy. There are rather small amount of high performace storage compared to the large amount of main memory, that is about 30GB at maximal usage.It is also investigates how the special purpose computers of Cosmic Fluid Dynamics computtations are reviewed. There also find a new algorithm for utilizing such special purpose computer not only in the fluid dynamics calculation but also in a radiative transfer computation.Through the research mentioned above, there has been clarified a systematic operating system which covers from workstations to the high-end computer server. In future, it is required to clarify what kind of user environment should be prepared for numerical simulation in astrophysics, and also to find out what kind of computer architecture and operating system will be suitable for astronomical computation. Less