![]() ![]() The asymptotic results agree well with those from 3D finite-difference simulation. We use the reciprocity relation between the virtual source and a monopole or a dipole source to obtain the asymptotic solutions of fluid pressure or horizontal displacement for the reflected wave. The wave reflected from a reflector outside the borehole is proved to be equivalent to the radiation of a virtual source outside the borehole. The radiation fields of a monopole and a dipole are computed using the steepest descent integration method. We derive asymptotic solutions of both the horizontal displacement and the fluid pressure for the reflected wave from the geological interfaces in this non-axisymmetric system. The other difficult issue is to quickly simulate the wave field of SWI to meet the needs of real-time data processing in field logging. This system can be used to determine the azimuth angle uniquely. We propose a new single-well imaging system with combined dipole and monopole receivers for a dipole source. ![]() Current SWI cannot determine the azimuth angle of the geological. ![]() In SWI, acoustic signals generated by a monopole or a dipole source in the borehole are reflected by geologic interfaces and received by arrays of receivers of the same type. Single-well imaging (SWI) is a borehole measurement technique aimed at detecting geological interfaces or structures tens of meters away from the borehole. ![]() Rendered examples of oceans waves generated by the model are given and a 10 second animation is described. The overall 'randomness' and 'short-crestedness' of the ocean is achieved by a combination of small variations within a train and large variations between trains. To give designers control over the shape of the ocean, the model of the overall surface includes multiple trains of waves, each with its own set of parameters and optional stochastic elements. The foam generated by the breakers is modeled by particle systems whose direction, speed and life expectancy is given by the surface model. Animation is easy, since time is built into the model. The ocean surface is modeled as a parametric surface, permitting the use of traditional rendering methods, including ray-tracing and adaptive subdivision. The model can also determine the position, direction, and speed of breakers. The surface of the ocean floor affects the refraction and the breaking of waves on the shore. The model can easily produce realistic waves shapes which are varied according to the parameters of the orbits. It is based on the Gerstner, or Rankine, model where particles of water describe circular or elliptical stationary orbits. We present a simple model for the surface of the ocean, suitable for the modeling and rendering of most common waves where the disturbing force is from the wind and the restoring force from gravity. Typical disadvantages to volumetric methods such as poor scalability and lack of control are addressed by. In addition, the pressure field, together with the Lagrange equations of motion, is used to simulate dynamic buoyant objects. The position of any free surface can thus be determined to a significantly higher resolution than that of the Navier-Stokes calculation. Local fluid velocity is then used to drive a height field equation or to convect massless marker particles. The resulting velocity and pressure fields describe the gross transport of liquid, including effects such as splashing, vorticity and overturning. A finite difference approximation to the NavierStokes equations is first applied to a low resolution, voxelized representation of the scene. Physically accurate 3D motion is achieved by performing a two-stage calculation over an arbitrary environment of static obstacles surrounded by fluid. We present a comprehensive methodology for realistically animating liquid phenomena. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |