Wind power has a great potential to be used as a renewable energy. As far as wind power turbines, the most common type is the horizontal axis wind turbine. The performance of the wind power turbine is controlled by the turbine design. If a three-dimensional model of the turbine blade with high accuracy is created by the general purpose CAD system, the model can be used for fluid dynamic simulations. Also, the CAM system can assist to machine the rib or the blade of the turbine by using the three-dimensional model. In this paper, a three-dimensional modeling method for the turbine blade is investigated in the general purpose CAD system. From the results, it has been confirmed that the model of the turbine blade with high accuracy can be created by adjusting the positions of the section profiles consisting of B-splines and using the loft function.

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We have developed a 3D-CAD education system based on computer assisted instruction (CAI). This system consists of lectures using an animated manual, exercises using an electronic text, evaluation using a 3D-CAD check function, and guidance using the study history. This system performs all the lessons except for the guidance. Thus, it can be used by a single teacher with a class of many students,　similarly to a conventional school. However, since both beginners and people experienced in 3D-CAD may be present in the same lesson, there is a problem of progress in lessons. Thus, we have developed a function that automatically creates exercises on subjects suited to the student's modeling capability. This paper gives an outline of this function (exercise subject creation function), and its effectiveness as an educational tool.

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In the previous paper, the authors proposed a 1-dimensional thermo-elastic model with regard to the mechanism of particleboard (PB) warping, and indicated that the model could describe well the behavior of longitudinal warping. Furthermore, being based on the model, it was shown that the dominant factor which caused the longitudinal warping was the temperature difference between both surfaces of PB. However, from the stand point of the temperature difference, it could not say that the effectivity of the model was adequately verified experimentally in the previous paper. Therefore, through the study in this paper on the influence of the temperature difference in the wider range upon the longitudinal warping, the effectivity of the model was verified anew. Meanwhile, since a PB is used as a plane panel, it is important that the mechanism of warping should be considered as a 2-dimensional problem in the second stage of the study. In this paper, aiming at the expanding the model into the 2-dimensional problem, the plane-warping and its regarding temperature neighboring the PB were measured and studied. Consequently, it follows from the results that the PB approximately deforms symmetrically in the direction of both longitudinal and lateral, and shows clearly the shape of anticlastic.

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