No abstract

In hot rolling process, scale is formed on steel surface by oxidation at high temperature. As the scale influences the friction between roll and workpiece, the scale affects rolling characteristics significantly. The influence has not been understood sufficiently due to experimental difficulties. The authors proposed to use glass powder to observe the scale as hot rolled. The pickled cold mild steel sheet was inserted to a furnace at hot rolling temperature (1273K) filled with argon. After 600 s, the atmosphere was changed from argon to air to allow oxide scale to grow for 0, 10, 40 s. After the oxidation, the sheet was rolled immediately on a two-high laboratory rolling mill. The thickness was reduced from 10 to 40%. After passing the roll bite, glass powder was sprinkled over the sheet. Scanning electron microscopy on the longitudional section revealed that the scale deformation is relatively uniform if the reduction is lower than 20%. If the reduction is higher than 30%, matrix steel is extruded through cracks in the scale to the outermost surfaces.

In this research, the authors succeeded in creating facial expressions made with the minimum necessary elements for recognizing a face. The elements are two eyes and a mouth made using precise circles, which are transformed to make facial expressions geometrically, through rotation and vertically scaling transformation. The facial expression patterns made by the geometric elements and transformations were composed employing three dimensions of visual information that had been suggested by many previous researches, slantedness of the mouth, openness of the face, and slantedness of the eyes. In addition, the relationships between the affective meanings of the visual information also corresponded to the results of the previous researches.The authors found that facial expressions can be classified into 10 emotions: happy, angry, sad, disgust, fear, surprised, angry*, fear*, neutral (pleasant) indicating positive emotion, and neutral (unpleasant) indicating negative emotion. These emotions were portrayed by different geometric transformations. Furthermore, the authors discovered the "Tetrahedral model," which can express most clearly the geometric relationships between facial expressions. In this model, each side connecting the face is an axis that controlled the rotational and vertically scaling transformations of the eyes and mouth.