In this paper we will prove several not so well known conditions for a quadrilateral to have an incircle. Four of these are different excircle versions of the characterizations due to Wu and Vaynshtejn.

In this paper, left and two sides tangential filtering decompositions are introduced. The filtering preconditioner constructed by the decomposition is combined with classical ILU(0) preconditioner in multiplicative ways to produce composite preconditioners. Analysis show that the composite preconditioners benefit from each of the preconditioners. On the filtering vector, we reveal that ones is ...

The sophisticated receptive field organization of motion-sensitive tangential cells in the visual system of the blowfly Calliphora vicina matches the structure of particular optic flow fields. Hypotheses on the tuning of particular tangential cells to rotatory self-motion are based on local motion measurements. So far, tangential cells have never been tested with global optic flow stimuli. Ther...

When we manipulate objects in everyday tasks, there are variations in the shape of the grasped surfaces, and the loads that potentially destabilize the grasp include time-varying linear forces and torques tangential to the grasped surfaces. Previous studies of the control of fingertip forces for grasp stability have dealt principally with flat grip surfaces and linear force loads. Here, we stud...

This paper presents numerical solutions and idealized analytical solutions of axisymmetric, f -plane models of the tropical cyclone boundary layer. In the numerical model, the boundary layer radial and tangential flow is forced by a specified pressure field, which can also be interpreted as a specified gradient balanced tangential wind field vgr(r) or vorticity field ζgr(r). When the specified ...

AIM The aim of the present study was to compare the success and complication rates of pediatric renal biopsy procedures between the angled tangential approach and the traditional approach. METHODS From 2004 to 2009 we prospectively enrolled pediatric patients who had undergone real time ultrasound guided renal biopsy with angled tangential approach. For comparison, we retrospectively reviewed...

This study investigated the effects of modifying contact finger forces in one direction-normal or tangential-on the entire set of the contact forces, while statically holding an object. Subjects grasped a handle instrumented with finger force-moment sensors, maintained it at rest in the air, and then slowly: (1) increased the grasping force, (2) tried to spread fingers apart, and (3) tried to s...