After the thermal quench of a tokamak disruption, the plasma current decays and is partly replaced by runaway electrons. A quantitative theory of this process is presented, where the evolution of the toroidal electric field and the plasma current is calculated self-consistently. In large tokamaks most runaways are produced by the secondary ͑avalanche͒ mechanism, but the primary ͑Dreicer͒ mechanism plays a crucial role in providing a "seed" for the avalanche. As observed experimentally, up to 50%-60% of the plasma current is converted into runaways in the Joint European Torus ͓P. H. Rebut et al., Nucl. Fusion 25, 1011 ͑1985͔͒, and the conversion is predicted to be somewhat larger in ITER ͓R. Aymar et al., Plasma Phys. Controlled Fusion 44, 519 ͑2002͔͒. Furthermore, the postdisruption current profile is found to be more peaked than the predisruption current-so much, in fact, that the central current density can increase although the total current falls. It is also found that the runaway current profile easily becomes radially filamented. These results may have implications for the stability of the postdisruption plasma.

In the early days of oilseed production, functions were often far removed, and actions taken by one operation were done for optimization of its own performance with little consideration on impacts made on subsequent processes. Within the last few years, the emphasis has changed from stand‐alone operations toward the integrated manufacturing facility, producing a more complete range of value‐added products from the raw seed to the dinner table. During this transition, operations have become more dependent on each other, as the individual functions involved must now consider the impact of their actions on the total process. At the same time, the scope of knowledge each operation must have of other functions has expanded, and it is important that at least a basic understanding of the “big picture” be available to the decision maker. The purpose of this Chapter is to provide an overview of the typical processes and interrelations associated with a total integrated facility.

A simple analytical modeling is made of the main breakdown properties of high-power microwave pulses propagating in air. Particular emphasis is given to breakdown levels, breakdown times, pulse erosion, and optimal pulse energy transfer. Comparison with recent experimental results shows good agreement.

The molecular dynamic simulation technique was used to model the vibrational behavior of crystalline (α and β cristobalite) and amorphous silica structures. To this end a refined potential function was developed, which allows one to reproduce the correct structural geometries, the corresponding infrared spectra, and to observe a reversible phase transformation between α and β cristobalite. The complex dielectric constants in the infrared frequency range were calculated from the dipole moment time correlation functions. While idealized cristobalite exhibits the simplest spectrum with only two narrow bands, the increase of structural complexity and reduction of symmetry characteristic for the real cristobalites and amorphous silica, creates additional features in the infrared spectra. These structural changes predominantly affect the coordination of oxygen, and generate a broader spread in the normal modes characterizing the vibrations of this species. A unique method for the identification of atomic trajectories corresponding to the mechanisms responsible for individual absorption bands, which is based on the concept of Fourier transform filtering, is used for the assignment of absorption bands to atomic motions.

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