Reviews have been made on the researches and developments for human models in the field of nuclear engineering. Until now, the related works have been made mainly for the modeling of plant operator and operator crew in the control room, but also there arise new tendencies of extending the modeling works for maintenance field as well as for personnel training purposes.
The whole range of human model research is divided into the five areas of (a) modeling for machine system, (b) measurement and analysis of human information behavior, (c) modeling of human internal information process, (d) modeling of human interaction with machine system, and (e) that of between human themselves. The real examples of the human model developments as well as their methods, applications, and the model validations are described, and then, the further subjects and efforts are pointed out which would be needed for the broader industrial application of the human modeling.

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For evaluating the possibility of applying a thermal plasma method to treatment of low level miscellaneous solid wastes, the effect of heating atmospheric gases on the material properties of the treated waste forms and the behavior of radionuclides were examined by conducting plasma melting tests of simulated miscellaneous solid wastes (iron, fly ash and wood) with surrogate nuclides. We found that the material properties of the treated waste forms have a homogeneous distribution of surrogate nuclides and low leaching rate of them: from the slag layers the rate was less than 10^-7 (g·cm^-2·d^-1)and from the metallic layers was less than 10^-5 (g·cm^-2·d^-1) in every atmospheric condition. The compressive strengths of the slag layers obtained in the oxidization conditions were over 50MPa. The migration behavior of Co, Ni, Nb, Sr and Ce was not influenced by the heating atmospheric conditions, and almost 100% of these nuclides migrated to the treated waste forms. Migration rate of Cs to the slag layers was also not influenced by the heating atmospheric gases except under extremely high reductive conditions, and a high residual rate of over 60% was obtained. These results show that a plasma melting method can be used for treatment of miscellaneous solid wastes.

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In order to provide a set of magnetohydrodynamic (MHD) equilibrium database which is indispensable for both the studies on improvement of energy confinement and stabilization of MHD activities in tokamaks, a high speed data-processing system synchronizing with JT-60 discharge sequence was newly developed by utilizing the latest model of high speed workstation and by optimizing the parallel processing technique to perform fast calculation of MHD equilibria. This high speed system was found to have a sufficient ability to complete the whole equilibrium calculations during each inter-shot period. Cooperating with the mass data storage subsystem preserving the latest equilibrium database automatically, the animated discharge monitoring subsystem provides valuable information for the JT-60 operator to determine control parameters of the succeeding discharge. This report describes the system performance realized in the JT-60 experiment.

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For test and research reactors, the core conversion to low-enriched uranium fuel is required from the viewpoint of non-proliferation of nuclear weapon material. Improvements of core performance are also required in order to respond to recent advanced utilization needs. In order to meet both requirements, a high-performance fuel element of high uranium density with Cd wires as burnable absorbers was adopted for JMTR core conversion to low-enriched uranium fuel.
From the result of examination of an adaptability of a few group constants generated by a conventional transport-theory calculation with an isotropic scattering approximation to a few group diffusion-theory core calculation for design of the JMTR high-performance fuel element, it was clear that the depletion of Cd wires was not able to be predicted accurately using group constants generated by the conventional method. Therefore, a new generation method of a few group constants in consideration of an incident neutron spectrum at Cd wire was developed. As the result, the most suitable high-performance fuel element for JMTR was designed successfully, and that allowed extension of operation duration without refueling to almost twice as long and offer of irradiation field with constant neutron flux.

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