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Example motion estimation

Nor is it difficult to modify this procedure to take account of the motion of a central atom, for example, to estimate the Mn-O-Mn bond angle 9) of the O-bridged molecule Mn20y. Here 9 is calculated from the intensities of symmetric and antisymmetric u(Mn-O-Mn) fundamentals using the relationship... [Pg.4380]

The Born-Oppenheimer approximation was developed in 1927 by the physicists Max Born (German) and J. Robert Oppenheimer (American), just one year after Schrodinger presented his quantum treatment of the hydrogen atom. This approximation method is the foundation for all of molecular quantum mechanics, so you should become familiar with it. The basic idea of the Born-Oppenheimer approximation is simple because the nuclei are so much more massive than the electrons, they can be considered fixed for many periods of electronic motion. Let s see if this is a reasonable approximation. Using H2 as a specific example, we estimate the velocity of the electrons to be roughly the same as that of an electron in the ground state (w = 1) of the hydrogen atom. From the Bohr formula, V = we calculate an electron velocity of 2.2 X 10 m sec . We... [Pg.214]

Parallel to, and often independent of, the correspondence-based approach, optical flow-based structure and motion estimation algorithms have flourished for more than two decades. Although robust dense optical flow estimates are still elusive, the field has matured to the extent that systematic characterization and evaluation of optical flow estimates are now possible. Methods that use robust statistics, generalized motion models, and filters have all shown great promise. Significant work that uses directly observable flow ( normal flow ) provides additional insight into the limitations of traditional approaches. An example of depth estimation using optical flow is shown in Fig. 8. [Pg.157]

The example design of a motion estimation application using the design script resulted in an architecture that can be compared with even the best manual designs. The careful selection of the transformation matrix produced an architecture with optimal I/O and control flow. Only control logic and I/O at the borders is needed, and the interface buffer sizes needed are very small. This shows that the proposed methodology and tools can indeed be used for complex real-life examples, with optimal results. [Pg.140]

Prediction of Critical Sizes. In order to use the above model for actual predictions, it is necessary to assign values to the relative velocity U0 this is, at the present level of knowledge, an extremely difficult task since, due to bubble motion (and perhaps the presence of fixed and moving internals in a fluid bed such as, for example, draft tubes) the particle movement in a fluidized bed is extremely complex. Some crude estimates of the relative velocity between particles have been made (Ennis etal., 1991) and these were expressed as... [Pg.387]

For example, in the case of PS and applying the Smoluchowski equation [333], it is possible to estimate the precipitation time, fpr, of globules of radius R and translation diffusion coefficient D in solutions of polymer concentration cp (the number of chains per unit volume) [334]. Assuming a standard diffusion-limited aggregation process, two globules merge every time they collide in the course of Brownian motion. Thus, one can write Eq. 2 ... [Pg.77]

In natural waters, unattached microorganisms move with the bulk fluid [55], so that no flux enhancement will occur due to fluid motion for the uptake of typical (small) solutes by small, freely suspended microorganisms [25,27,35,41,56,57], On the other hand, swimming and sedimentation have been postulated to alleviate diffusive transport limitation for larger organisms. Indeed, in the planar case (large r0), the diffusion boundary layer, 8, has been shown to depend on advection and will vary with D according to a power function of Da (the value of a is between 0.3 and 0.7 [43,46,58]). For example, in Chapter 3, it was demonstrated that in the presence of a laminar flow parallel to a planar surface, the thickness of the diffusion boundary layer could be estimated by ... [Pg.456]

Dynamic probe methods Another indirect strategy for emalysis of gel structure is the measurement of the mobility of dynsumic probes whose sizes are well characterized. For example, dynsumic light scattering or any other method for diffusivity determination (for examples, see 37) can be used to measure the motions, through a gel matrix, of a series of spherically shaped particles with varying sizes. To oversimplify greatly, if, as probe size is raised, a dramatic decrease in diffusivity is found, then the "mesh" size of the polymer gel may be estimated. [Pg.16]

The depth of the altered layer, in our opinion, can be estimated by the following procedure. The energy (momentum) pulse is likely to penetrate the lattice more deeply than does the particle itself. For example, 200 eV Xe ions collide with a tungsten lattice and are primarily reflected back into the gas phase. Nevertheless, atomic motion induced by the impinging ion probably occurs to a depth of 30-50 A beneath the surface. Therefore, a crude estimate (but probably the best available) of the depth of the altered layer can be obtained by assuming a constant value of 30 A at energies where... [Pg.101]

Some numerical examples are given. For a semi-infinite copper melt initially at the fusion temperature, losing heat with an over-all heat transfer coefficient of 0.5 B.t.u./(hr.)(ft.2)(°F.) to the surroundings at ambient temperature, after 4 hr. 771 = 0.98, and the estimated thickness of solidified copper is 44 in. with a 12% error. A second example is a steel sheet subjected to a slowly flowing stream of very hot gas, such that a uniform heat flux of 105 B.t.u./(hr,)(ft.2)(°F.) is imposed at the surface with negligible motion of the melt. After 200 sec., 771 = 0.68, and the melt thickness is estimated to be 1.26 in., with a possible error of 8.6%. [Pg.126]


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