We investigated the angular resolution subserving the haptic perception of raised-line drawings by measuring how accurately observers could discriminate between two angle sizes under various conditions. We found that, for acute angles, discrimination performance is highly dependent on exploration strategy: mean thresholds of 2.9 degrees and 6.0 degrees were found for two different exploration s...

The present paper describes a testing method for five-axis machining centers using three-dimensional circular interpolation movement equivalent to cone-frustum cutting. In the present paper, the test conditions, such as the half apex angle of cone-frustum and the sensitive directions of the ball bar device were investigated. In addition, the sensitivity coefficient of each axis was investigated...

We are given a finite set of m points (guards) G in the plane R 2 and an angle 0 ≤ Θ ≤ 2π. A Θ-cone is a cone with apex angle Θ. We call a Θ-cone empty (with respect to G) if it does not contain any point of G. A point p ∈ R is called Θ-guarded if every Θ-cone with apex located at p is non-empty. Moreover, the set of all Θ-guarded points is called Θ-region. We first show how to construct a data...

Changes of cervical sagittal alignment during motion in cervical kyphosis patients have never been published before. This study was to investigate the changes and provide a better reference for orthopedic treatment.Randomized double-blind repeat trial was carried out on 60 patients with cervical kyphosis. On standard position, hyper flexion, and hyper extension sagittal radiographs, the followi...

We consider self-avoiding polymers attached to the tip of an impenetrable probe. The scaling exponents gamma(1) and gamma(2), characterizing the number of configurations for the attachment of the polymer by one end, or at its midpoint, vary continuously with the tip's angle. These apex exponents are calculated analytically by epsilon expansion, and numerically by simulations in three dimensions...

The rotational spectrum of thiozone, S3, has been observed for the first time. From the rotational constants of the normal and 34S isotopic species, a precise geometrical structure has been derived: S3 is a bent chain with a bond to the apex S of length 1.917(1) A and an apex angle of 117.36(6) degrees . The derived structural parameters indicate substantial double-bonding character in S3 and s...

Forward blowing from a pair of plasma actuators on the leeward surface and near the apex is used to switch the asymmetric vortex pair over a cone of semi-apex angle 10 at high angles of attack. The experiments were perfomed in a 3.0 m×1.6 m open-circuit wind tunnel at Reynolds number of 5×10 and 10 based on the cone base diameter. Pressure measurements show that by appropriate design of the act...

In a recent letter (ApJ 517, L155) Lenz et al. have shown the evidence of uniform temperature along steady long coronal loops observed by TRACE in two diierent pass-bands (171 A and 195 A lters). We propose that such an evidence can be explained by the sub-arcsecond structuring of the loops across the magnetic eld lines. In this perspective , we present a model of a bundle of six thin parallel ...