The exponential growth of computer power in the last 10 years is now creating a great challenge for parallel programming toward achieving realistic performance in the field of scientific computing. To improve on the traditional program for numerical simulations of laser fusion in inertial confinement fusion (ICF), the Institute of Applied Physics and Computational Mathematics (IAPCM) initializes a software infrastructure named J Adaptive Structured Meshes applications INfrastructure (JASMIN) in 2004. The main objective of JASMIN is to accelerate the development of parallel programs for large scale simulations of complex applications on parallel computers. Now, JASMIN has released version 1.8 and has achieved its original objectives. Tens of parallel programs have been reconstructed or developed on thousands of processors. JASMIN promotes a new paradigm of parallel programming for scientific computing. In this paper, JASMIN is briefly introduced. BackgroundComputers have been indispensable for scientific research. In the past ten years, the growth of computer power has increased by over one thousand times [1]. Such growth is now launching a new field of computational science [2]. Computational simulation has the great potential to join theory and experiments as a third powerful research methodology. In recent years, the new discipline has already begun yielding important and exciting results to simulate phenomena such as supernova explosions, inertial confinement fusion (ICF), nuclear explosions, the effect of space weather, and so forth [3,4]. However, it is clear so far, that much computational science is troublingly immature. In particular, programming is becoming a great challenge as was reported five years ago [5], and will be even more challenging in the future [6].The programming challenges mainly arise from two types of increasing complexity [7,8]. The first is the computer architecture. The memory wall is still the key bottleneck for realistic performance; the increasing number of cores in each CPU increases the seriousness of this bottleneck. The data structures should be matched to a cached-based memory hierarchy. However, aggregation techniques are indispensable for the construction of computers. More and more cores are integrated into each CPU, and more and more CPUs are clustered into each computing node, and hundreds or thousands of nodes are interconnected. Parallel algorithms should have sufficient parallelism to utilize so many cores. The design of such data structures and parallel algorithms are too professional for the application users.The second complexity is the application system. Large scale simulations are mainly used to study the characteristics of complex systems. With the increasing of computer capabilities, the complexity of the application system should also increase simultaneously. However, the increasing complexity brings many new problems. Firstly, the fast parallel algorithms are usually required for the solution of large scale discrete systems. Though many such algorithms have b...

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The most investigated ion acceleration mechanisms in solid targets driven by intense laser pulses are revisited, including the target normal sheath acceleration (TNSA), radiation pressure acceleration (RPA), hybrid scheme of radiation pressure-sheath acceleration and Coulomb explosion (CE). In these acceleration mechanisms, the competition, between thermal pressure, radiation pressure and electrostatic pressure, decides the acceleration dynamics. Thermal pressure induced by hot electrons dominates TNSA, while RPA is ideally driven by steady radiation pressure and CE is mainly governed by the electrostatic pressure stored in the target. Two-dimensional particle-in-cell simulations are performed to display and elucidate this dynamical evolution among different mechanisms by changing the target thickness.