Digital Zenith Camera Systems (DZCS) are dedicated astronomical-geodetic measurement systems for the observation of the direction of the plumb line. A DZCS key component is a pair of tilt meters for the determination of the instrumental tilt with respect to the plumb line. Highest accuracy (i.e., 0.1 arc-seconds or better) is achieved in practice through observation with precision tilt meters i...

In this paper experimentally, the friction-stir welding of the polypropylene sheets with 40% glass fiber has been investigated. Comparison to other welding methods, the strength of the joint is the most important feature in this process. Many parameters such as tool geometry, rotational speed, linear velocity, and tilt angle are very important as input parameters in this type of welding. Theref...

Healthy humans maintained equilibrium on rocking supports (seesaw) of different curvatures and heights. We recorded platform tilt, horizontal displacements of the upper body, ankle joint angle and activity of ankle joint muscles. Subjects maintained balance by making seesaw rotations placing the support under the body's centre-of-gravity. Forward displacement was balanced by compensatory planta...

– A layer of sand of thickness h flows down a rough surface if the inclination is larger than some threshold value θstart which decreases with h. A tentative microscopic model for the dependence of θstart with h is proposed for rigid frictional grains, based on the following hypothesis: (i) a horizontal layer of sand has some coordination z larger than a critical value zc where mechanical stabi...

the price of single point diamond tools with a sharp tip is very high due to complex machining process and highly expensive machining equipments. yet, the performance is not quite satisfactory. in this paper, we have presented a very simple and cost effective machining process for the sharpening and polishing of diamond stylus using low energy reactive ion beam machining (ribm). in our method, ...

We have demonstrated a personal identification system that is based on near-infrared finger vein patterns. Finger vein patterns of 678 volunteers are acquired by transmitting near-infrared light through a finger and capturing the image with a CCD camera. These vein patterns are enhanced by a background-reduction filter. The similarity between two patterns is then quantified by use of the normal...

The direction of the upward light emission has different polluting effects on the sky depending on the distance of the observation site. We studied with detailed models for light pollution propagation the ratio bH bL , at given distances from a city, between the artificial sky luminance bH produced by its upward light emission between a given threshold angle θ0 and the vertical and the artifici...

The preceding paper has reported the fact that visual lines undergo what may be termed adaptation followed by a negative after-effect with respect to their direction or orientation in the frontal visual field. A line possessing the characteristic of tilt appears to become less tilted during the course of a continued inspection, and thereafter a line objectively vertical or horizontal appears to...