Vertical displacement

About: Vertical displacement is a research topic. Over the lifetime, 3593 publications have been published within this topic receiving 35810 citations.

Touch-screen image scrolling system and method

Abstract: Electronic image displays, of lists that extend beyond the vertical display dimension of the display screen, are displaced in the vertical direction by touching the screen with a finger and then moving the finger in the desired direction on the screen. In a natural manner, the initial speed of displacement of the displayed image corresponds to the speed of motion of the finger along the screen. When the user's finger is disengaged from the screen, the system senses the disengagement and thereafter allows the vertical displacement speed of the image to decrease at a controlled rate. When it is desired to stop the motion of the image at a given point, or to make a selection from the displayed image, the system measures the length of time that the finger is in contact with the screen and the distance that the finger is moved during that time, to determine if a selection is desired or if it is desired only to stop displacement of the image. That is, a short term contact with the screen, say 500ms or less, accompanied by little or no displacement on the screen, can be identified as an intended selection, while a longer contact with little or no accompanying displacement can be interpreted as being intended to stop the motion of the image without making a selection.

Force platforms as ergometers

Abstract: Walking and running on the level involves external mechanical work, even when speed averaged over a complete stride remains constant. This work must be performed by the muscles to accelerate and/or raise the center of mass of the body during parts of the stride, replacing energy which is lost as the body slows and/or falls during other parts of the stride. External work can be measured with fair approximation by means of a force plate, which records the horizontal and vertical components of the resultant force applied by the body to the ground over a complete stride. The horizontal force and the vertical force minus the body weight are integrated electronically to determine the instantaneous velocity in each plane. These velocities are squared and multiplied by one-half the mass to yield the instantaneous kinetic energy. The change in potential energy is calculated by integrating vertical velocity as a function of time to yield vertical displacement and multiplying this by body weight. The total mechanical energy as a function of time is obtained by adding the instantaneous kinetic and potential energies. The positive external mechanical work is obtained by adding the increments in total mechanical energy over an integral number of strides.

Tsunami generation by horizontal displacement of ocean bottom

Abstract: Tsunami generation by an earthquake is generally modeled by water surface displacement identical to the vertical deformation of ocean bottom due to faulting. The effect of horizontal deformation is usually neglected. However, when the tsunami source is on a steep slope and the horizontal displacement is large relative to the vertical displacement, the effect becomes significant. We show this for two recent earthquakes which generated much larger tsunamis than expected from seismic waves. In the case of the 1994 June 2 Java, Indonesia, earthquake, the focal mechanism was a very shallow dipping thrust and the source was near a very steep trench slope. In the case of the 1994 Nov. 14 Mindoro, Philippines, earthquake, strike-slip faulting extended from ocean to land perpendicular to the coast line. In both cases, we found that the horizontal motion of slope had an important contribution to the tsunami generation.

The 2011 Tohoku-Oki Earthquake: Displacement Reaching the Trench Axis

Abstract: We detected and measured coseismic displacement caused by the 11 March 2011 Tohoku-Oki earthquake [moment magnitude (MW) 9.0] by using multibeam bathymetric surveys. The difference between bathymetric data acquired before and after the earthquake revealed that the displacement extended out to the axis of the Japan Trench, suggesting that the fault rupture reached the trench axis. The sea floor on the outermost landward area moved about 50 meters horizontally east-southeast and ~10 meters upward. The large horizontal displacement lifted the sea floor by up to 16 meters on the landward slope in addition to the vertical displacement.

Propagation of Tremors over the Surface of an Elastic Solid.

Abstract: Wave phenomena which are seen along the surface of a semi-infinite elastic solid when subjected to an impulsive line force in the direction normal to its surface have been studied. The results obtained are as follows.(1) Immediately after the impulsive force is removed, the vertical displacement is downward in the neighbourhood of the origin, and it is upward outside that downward domain. (§3)(2) In the downward (upward) domain, the horizontal displacement is toward (away from) the origin. (§4)(3) The surface deformations thus produced are propagated with the velocity of RAYLEIGH wave without conspicuous changes in form. (§3 and §4)(4) The wave length of the RAYLEIGH wave is proportional to the time of duration of the impulse, and is of the same order of extent as that of the downward domain at the moment when the force is removed. (§3)