Abstract: A programmable computer is used to perform the following. 3D seismic data sets, corresponding to each azimuth in seismic data obtained from a multi-azimuth marine seismic survey, are migrated in grids oriented with the corresponding azimuth. Acquisition geometry is stored for each trace in the seismic data sets for each azimuth. Residual analysis, based on the corresponding azimuth, is performed on each of the migrated data sets, generating residuals and reflectors for each azimuth. The residuals and reflectors generated for each azimuth are rotated and merged on a master grid. Reflection tomographic inversion is applied iteratively to the rotated and merged residuals and reflectors to update a velocity model using the acquisition geometry as based on the master grid. The earth's subsurface is imaged using the updated velocity model.

Abstract: A programmable computer is used to perform the following. 3D seismic data sets, corresponding to each azimuth in seismic data obtained from a multi-azimuth marine seismic survey, are migrated in grids oriented with the corresponding azimuth. Acquisition geometry is stored for each trace in the seismic data sets for each azimuth. Residual analysis, based on the corresponding azimuth, is performed on each of the migrated data sets, generating residuals and reflectors for each azimuth. The residuals and reflectors generated for each azimuth are rotated and merged on a master grid. Reflection tomographic inversion is applied iteratively to the rotated and merged residuals and reflectors to update a velocity model using the acquisition geometry as based on the master grid. The earth's subsurface is imaged using the updated velocity model.

Abstract: A bicycle with a slant backrest frame includes a bicycle embodiment, and a power unit wherein the bicycle embodiment is equipped with a saddle having a slant backrest, and a rectangular central tube disposed under the saddle thereof in communication with a lower tube to which a switch device is fixedly attached at a preset position. The power unit made up of a rear loading bracket and a storage battery is adapted to the central tube with the rear loading bracket securely fixed to a slant flat opening of the central tube and the storage battery retained at a receiving cavity of the central tube therein. In practical use, the bicycle embodiment can be either pedaled by feet or electrically moved via the power unit conductively linked to the switch device thereof.

Abstract: A handlebar structure for an electrically powered vehicle includes a front fork unit, a connector bar unit, and a handle unit wherein the front fork unit having a coupling section protruding at the top thereof is engaged with the connector bar unit having a retaining block adapted therein, and the handle unit is joined to an engaging cavity of the connector bar unit to form a two-stage handlebar adjustment structure. A top quick release unit is applied to clamp tight the handle unit for location at the connector bar thereto, and a bottom quick release unit is screwed up to the retaining block thereof to compress a spring element adapted at the retaining block therein.

Abstract: Folding structure for main handle of handle-controlled skate board, including a T-shaped fixing section integrally formed on upper side of front end of a body of the handle-controlled skate board. An upper side of front portion of a longitudinal section of the T-shaped fixing section is formed with a guiding inclination angle. A lower side of the guiding inclination angle is formed with an arch locating notch immediately adjacent to the guiding inclination angle. Two spring engaging bodies respectively laterally protrude from two sides of the middle of the longitudinal section of the T-shaped fixing section near the top face thereof. A rear section of the T-shaped fixing section is formed with a pivot hole near the center thereof. A supporting frame is welded on rear side of the stem. A lower side of front section of the supporting frame is formed with an arch escape recess. A middle portion of the escape recess is formed with a spring locating groove.

Abstract: An improved stepping rod normally mounted to the rear axle of a bicycle has one end provided with a multi-angled countersunk cavity in correspondence to a locking nut secured to each end of the axle of a rear wheel of a bicycle and an extra locking nut is placed in a hollow interior of the stepping rod to lock the stepping rod firmly in place so that the stepping rod will not rotate when a person steps thereon and the locking nuts will not loosen during in use. Moreover, the stepping rod can be easily and quickly removed from and mounted to the axle of a rear wheel of a bicycle without affecting the original bicycle structure.