Space- and object-based attention components were examined in neurologically normal and parietal-lesion subjects, who detected a luminance change at 1 of 4 ends of 2 outline rectangles. One rectangle end was precued (75% valid); on invalid-cue trials, the target appeared at the other end of the cued rectangle or at 1 end of the uncued rectangle. For normals, the cost for invalid cues was greate...

In this paper we analyze the previous attacks on the block cipher SHACAL-1 and show that all the differential-based attacks fail due to mistreatment of XOR differences through addition. We show that the previously published differential and rectangle attacks on SHACAL-1 fail as some of the underlying differentials are impossible. The relatedkey rectangle attacks on the cipher generally fail, bu...

We consider arrangements of axis-aligned rectangles in the plane. A geometric arrangement specifies the coordinates of all rectangles, while a combinatorial arrangement specifies only the respective intersection type in which each pair of rectangles intersects. First, we investigate combinatorial contact arrangements, i.e., arrangements of interior-disjoint rectangles, with a triangle-free inte...

We prove that the maximal inscribed beamlet is at least 1/7 of an arbitrary line segment (i.e., beam). The implication of this result is addressed.