Topics of research and development on concrete cask storage of spent nuclear fuel

This paper addresses topics of research and development (R&D) being challenged for realization of concrete cask storage of spent nuclear fuel in Japan. Comparison between metal cask storage and concrete cask storage is addressed. Background of these R&D and current status of technology on spent fuel storage are described. Need and design concepts of concrete cask storage technology, tests and evaluation of integrity of spent fuel, materials, concrete casks under normal and accident conditions, monitoring technology, etc. are systematically arranged and introduced. Topical problems of these R&D are described.     

Developments in fracture mechanics and non-destructive examination

The purpose of this paper is to give a brief review of the major developments and trends that have occurred in some of the technical areas covered by Division G of SMiRT since the first conference was held in Berlin in 1971. As with any human activity, time and experience produce organic change so that the technical areas covered by Division G have changed somewhat over the 18 years of its existence. As first conceived by Tom Jaeger, Division G was one of two divisions devoted to Light Water Reactor Components other than fuel and cladding. Division F was conceived with Core Structures and Piping whilst Division G was devoted to the Steel Reactor Pressure Vessels.     

Neural networks in computational mechanics

Summary In this paper, recent neural network applications, epecially to the fields related with the computational mechanics, were surveyed. The most outstanding characteristics of the neural network aided computation is that neither complicated programmings nor rigid algorithms are needed. Another important point is that the neural network's inherent parallelism, that is, concurrent signal transmissions over numerous, information processing elements suits the massively parallel computer architectures. First, we briefly review the neural network applications to the computational mechanics fields from recent publications, and describe the mathematical basis of the neural network. Next, the following topics are detailed: quantitative nondestructive evaluation, structural identification, modeling of viscoplastic material behaviors, crack growth analysis of welded specimens, structural design, parameter estimation for nonlinear finite element analyses, and equation solver.     

Cracked beam under influence of dynamic electromagnetic force

This paper is concerned with both numerical analysis and experiment on the fracture phenomena related to the electromagnetic force, considering an edge-cracked beam which carries a transient current I and is placed in a uniform and steady magnetic field B₀.As for the numerical study, isoparametric quarter point elements are used to treat the singularities at the crack tip both for the stress and the current density. Also some discussions are presented on the application of nonlinear fracture mechanics to the present problem, the temperature increase at the crack tip and the skin effect of the electric current.     

Fatigue crack separation and merging simulation using the smoothed particle hydrodynamics

International Journal of Fracture - The present paper proposes a new computational method for the fatigue crack propagation in a metallic structure using the smoothed particle hydrodynamics (SPH)....     

Improvement in output power of vibration generators based on piezoelectric elements by using internal capacitor cancel control rectifier

Recently, energy harvesting has attracted increasing attention. The present study focuses on vibration generators based on piezoelectric elements by proposing an internal capacitor cancel control (ICCC) rectifier to improve the output power. The proposed rectifier cancels the internal capacitor to improve the output power while retaining the maximum output power. Accordingly, this paper experimentally demonstrates the improvement in output power by using the ICCC rectifier compared to conventional circuits and the previous proposed circuit.