DISSIPATIVE INSTABILITIES AND SUPERRADIATION REGIMES (CLASSIC MODELS)

The generation of an electromagnetic field by oscillators in an open resonator is discussed in a one-dimensional approximation. In this case, the development of the so-called dissipative instability  the dissipative generation regime. Such an instability with the generation of electromagnetic oscillations arises when the decrement of oscillations in an open resonator in the absence of oscillators turns out to be greater than the increment of the resulting instability of the system of oscillators placed in this resonator. It is assumed that the oscillators do not interact with each other, and only the resonator field affects their behavior. If the resonator field is absent or small, the superradiance regime is possible, when the radiation of each oscillator is essential and the field in the system is the sum of all the eigenfields of the oscillators. In the dissipative regime of instability generation, the system of oscillators is synchronized by the induced resonator field. The synchronization of the oscillators in the superradiance mode owes its existence to the integral field of the entire system of oscillators. With a weak nonlinearity of the oscillators, a small initiating external field is required to excite the generation regime. It is noteworthy that the maximum value of the superradiance field is approximately two times less than the maximum field that the same particles could generate if they were at the same point. In all cases, for a given open resonator, the superradiance field turned out to be somewhat larger than the resonator field. Nevertheless, for the same resonator, the increments and attainable field amplitudes in both cases are of the same order of magnitude.

Class Actions in Historical and Comparative Perspective

This chapter outlines the historical and comparative context of class actions that have developed since their modern origins in the United States. It traces the development of the United States as a first generation regime, followed by Canada and Australia as second generation regimes. It also examines the recent efforts to institute collective mechanisms and the ways in which these developments have progressed. The chapter focuses on first and second generation regimes for comparative insights in order to understand their influencing developments in England and Wales as a third generation regime. It illuminates and situates developments in a broader historical and comparative perspective to provide a better sense of the lineage of the vehicle and the extent to which extant developments in England and Wales are falling short of their access to justice potential.

CW subterahertz gyrotron operating at high cyclotron harmonics

At the IAP RAS, a subteraherz continuous-wave large orbit gyrotron (LOG) operating directly at the second, third, and fourth cyclotron harmonics at frequencies of 0.26, 0.39, and 0.52 THz, is developed and created. The paper presents the results of experimental testing of LOG at the second and third harmonics carried out to date in the long-pulses regime (duration 0.1–60 s) with the transition to continuous- wave generation regime.

Optimization of the foam generation regime in a cylindrical channel

Mass and multi-purpose use of air-mechanical foams from gas-liquid mixtures predetermines the need to establish the physical and technical patterns of their formation in high-efficiency generating plants. The paper presents the results of optimizing the foaming regimes, taking into account the joint influence of all probable factors coming from the technology of the process of obtaining stable disperse structures. A regression model has been developed that makes it possible to determine optimal parameters of the foaming regime with the required structure and thermal properties.