Issues related to 3d turtle’s navigation and geometrical figures’ manipulation in the simulated 3d space of a newly developed computational environment, MaLT, are reported and discussed here. The joint use of meaningful formalism and the dynamic manipulation of graphically represented 3d figures seem to offer new resources and to pose new challenges as far as geometrical activities and construc...

We derive easy-to-handle approximations for the polar gap electric field due to inertial frame dragging as derived by Harding & Muslimov (1998). A formula valid for polar gap height comparable to the polar cap radius is presented.

Medium-sized touch displays, sized 30 to 50 inches, are becoming more affordable and more widely available. Prolonged use of such displays can result in arm fatigue or skin irritation, especially when multiple long distance drags are involved. To address this issue, we present TapDrag, an alternative dragging technique that complements traditional dragging with a simple tapping gesture on both ...

brass ferrules have been used as packing in a laboratory- scale glass distillation column approaching pilot plant size because of their availability in all sizes and low cost. the available size range is such that these ferrules could also be used in industry and the results of this study could be scaled up. the performance of the new packing has been compared with the performance of glass pack...

in the present study, computational fluid dynamics (cfd) techniques and artificial neural networks (ann) are used to predict the pressure drop value (δp ) of al2o3-water nanofluid in flat tubes. δp  is predicted taking into account five input variables: tube flattening (h), inlet volumetric flow rate (qi  ), wall heat flux (qnw  ), nanoparticle volume fraction (φ) and nanoparticle diameter (dp ...

the harvested walnut has a relatively high moisture content of 30% compared with the safe storage moisture content of 8%. one of the common means of reducing the moisture content is by drying. for design of drying and other aeration systems for agricultural products including walnuts, the relationship between the drop in pressure and airflow velocity must be known. an airflow resistance app...

Let m,n, r be nonzero fixed positive integers, R a 2-torsion free prime ring, Q its right Martindale quotient ring, and L a non-central Lie ideal of R. Let D : R −→ R be a skew derivation of R and E(x) = D(xm+n+r)−D(xm)xn+r − xmD(xn)xr − xm+nD(xr). We prove that if E(x) = 0 for all x ∈ L, then D is a usual derivation of R or R satisfies s4(x1, . . . , x4), the standard identity of degree 4.

ASTRONOMY AND ASTROPHYSICS Approximate expressions for polar gap electric field of pulsars Abstract. We derive easy-to-handle approximations for the polar gap electric field due to inertial frame dragging as derived by Harding & Muslimov (1998). A formula valid for polar gap height comparable to the polar cap radius is presented.

Multi-touch input on interactive surfaces has matured as a device for bimanual interaction and invoked widespread research interest. We contribute empirical work on direct versus indirect use multi-touch input, comparing direct input on a tabletop display with an indirect condition where the table is used as input surface to a separate, vertically arranged display surface. Users perform signifi...

We present a software planning tool that provides intuitive visual feedback for finding suitable positions of hearing implants in the human temporal bone. After an automatic reconstruction of the temporal bone anatomy the tool pre-positions the implant and allows the user to adjust its position interactively with simple 2D dragging and rotation operations on the bone's surface. During this proc...