The title compound, C12H10BrN5O3S2·C3H7NO, displays an almost planar amine group. The inter-planar angle between the rings is 31.72 (6)°. The residues are associated into ribbons parallel to [110] by three classical hydrogen bonds; one from each amine Hamine to ODMF and one from NHamide to Ooxo. Adjacent ribbons are connected by translation parallel to the c axis by a 'weak' hydrogen bond Hmeth...

This paper investigates the singular curves in the joint space of a family of planar parallel manipulators. It focuses on special points, referred to as cusp points, which may appear on these curves. Cusp points play an important role in the kinematic behavior of parallel manipulators since they make possible a nonsingular change of assembly mode. The purpose of this study is twofold. First, it...

Parallel robots represent way to considerably improve accuracy and speed of industrial machine tools and their centres. This paper deals with the preparatory operations: homing and calibration, which precede the start-up of the robot work, i.e. real control process. Their procedures are discussed with respect to planar parallel robots and their control. In this paper, as a suitable control stra...

It is proved that every series-parallel digraph whose maximum vertex-degree is ∆ admits an upward planar drawing with at most one bend per edge such that each edge segment has one of ∆ distinct slopes. This is shown to be worst-case optimal in terms of the number of slopes. Furthermore, our construction gives rise to drawings with optimal angular resolution π ∆ . A variant of the proof techniqu...

Refinement is a fundamental design technique that has often challenged the “formal methods” community. In most cases, mathematical elegance and proof manageability have been chosen over flexibility and freedom, which are often needed in practice to deal with unexpected or critical situations. The issue of refinement becomes even more critical when dealing with real-time systems where time analy...

We show how to construct an O p n separator decomposition of a planar graph G in O n time Such a decomposition de nes a binary tree where each node corresponds to a subgraph of G and stores an O p n separator of that subgraph We also show how to construct an O n way decomposition tree in parallel in O log n time so that each node corresponds to a subgraph of G and stores an O n separator of tha...

The greedy triangulation of a nite planar point set is obtained by repeatedly inserting a shortest diagonal that doesn't intersect those already in the plane. We show that the problem of constructing the greedy triangulation of a nite set of points with integer coordinates in the plane is P-complete. This is the rst known geometric P-complete problem where the input is given as a set of points....

This paper proposes a systematic algorithm based on the interval analysis concept in order to obtain the maximal singularity-free circle or sphere within the workspace of parallel mechanisms. As case studies the 3-RPR planar and 6-UPS parallel mechanisms are considered to illustrate the relevance of the algorithm for 2D and 3D workspaces. To this end, the main algorithm is divided into four sub...