is the normal force exerted by each surface on the other, directed perpendicular normal to the surface. the coulomb friction may take any value from zero up to , and the direction of the frictional force against a surface is opposite to the motion that surface would experience in the absence of friction.
a vibrating shuttle is a bobbin driver design used in home lockstitch sewing machines during the second half of the 19th century and the first half of the 20th century. it supplanted earlier transverse shuttle designs, but was itself supplanted by rotating shuttle designs.
in signal processing, cross-correlation is a measure of similarity of two series as a function of the displacement of one relative to the other. this is also known as a sliding dot product or sliding inner-product.it is commonly used for searching a long signal for a shorter, known feature. it has applications in pattern recognition, single particle analysis, electron tomography, averaging .
moiré patterns are often an artifact of images produced by various digital imaging and computer graphics techniques, for example when scanning a halftone picture or ray tracing a checkered plane the latter being a special case of aliasing, due to undersampling a fine regular pattern . this can be overcome in texture mapping through the use of mipmapping and anisotropic filtering.
center-pivot irrigation sometimes called central pivot irrigation , also called water-wheel and circle irrigation, is a method of crop irrigation in which equipment rotates around a pivot and crops are watered with sprinklers. a circular area centered on the pivot is irrigated, often creating a circular pattern in crops when viewed from above sometimes referred to as crop circles .
vibrational circular dichroism vcd is a spectroscopic technique which detects differences in attenuation of left and right circularly polarized light passing through a sample. it is the extension of circular dichroism spectroscopy into the infrared and near infrared ranges.. because vcd is sensitive to the mutual orientation of distinct groups in a molecule, it provides three-dimensional .
in a nonuniform circular motion, i.e., the speed along the curved path is changing, the acceleration has a non-zero component tangential to the curve, and is not confined to the principal normal, which directs to the center of the osculating circle, that determines the radius for the centripetal
the vibration of plates is a special case of the more general problem of mechanical vibrations.the equations governing the motion of plates are simpler than those for general three-dimensional objects because one of the dimensions of a plate is much smaller than the other two.
polarized light microscopy can mean any of a number of optical microscopy techniques involving polarized light.simple techniques include illumination of the sample with polarized light. directly transmitted light can, optionally, be blocked with a polariser orientated at 90 degrees to the illumination.
the properties of an idealized drumhead can be modeled by the vibrations of a circular membrane of uniform thickness, attached to a rigid frame. due to the phenomenon of resonance, at certain vibration frequencies, its resonant frequencies, the membrane can store vibrational energy, the surface moving in a characteristic pattern of standing waves.
in physics, circular motion is a movement of an object along the circumference of a circle or rotation along a circular path. it can be uniform, with constant angular rate of rotation and constant speed, or non-uniform with a changing rate of rotation. the rotation around a fixed axis of a
attrition between grinding balls and ore particles causes grinding of finer particles. sag mills are characterized by their large diameter and short length as compared to ball mills. the inside of the mill is lined with lifting plates to lift the material inside the mill, where it then falls off the plates onto the rest of the ore charge.