This paper is about two arrangements of hyperplanes. The first — the Shi arrangement — was introduced by Jian-Yi Shi to describe the Kazhdan-Lusztig cells in the affine Weyl group of type A. The second — the Ish arrangement — was recently defined by the first author who used the two arrangements together to give a new interpretation of the q, t-Catalan numbers of Garsia and Haiman. In the prese...

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...

the purpose of this study was to compare the effects of different combinations of mental and physical practices on the acquisition and retention of a motor skill in mentally retarded male students. subjects were 40 guidance students who were healthy and novice in basketball penalty shot. they were selected randomly and were assigned to 5 homogeneous groups (4 as experimental and 1 as control) b...

We address the problem of estimating the phase φ given N copies of the phase rotation uφ within an array of quantum operations in finite dimensions. We first consider the special case where the array consists of an arbitrary input state followed by any arrangement of the N phase rotations, and ending with a POVM. We optimise the POVM for a given input state and fixed arrangement. Then we also o...

background: emphasis on revise and provide new methods of evaluation in medical colleges are widely increasing. evaluation methods based on clinical practice and students’ performance appraisement in health care system and in medical student is introduced as an effective method in some studies. methods: the aim of this study was to consider the usefulness of a new method to evaluate the medical...

Given n points in the plane and an integer k, the slope selection problem is to nd the pair of points whose connecting line has the k-th smallest slope. (In dual setting, given n lines in the plane, we want to nd the vertex of their arrangement with the k-th smallest x-coordinate.) Cole et al. 6] have given an O(n log n) solution (which is optimal), using the parametric searching technique of M...