Suchergebnisse

In this paper, effect of the input DC electrical parameters, such as, pulse shape, cathode voltage and the postacceleration voltage on the performance of reltron oscillator have been investigated. For this purpose, a typical reltron oscillator has been designed and simulated. The mode of excitation, resonant frequency and electric field patterns in the RF modulation cavity of the reltron structure has been studied through electromagnetic simulation. The RF output performance and effect of DC electric pulse shape is studied through 3D PIC simulation. To get a practical insight of the excitation signal effect on the performance of device operation, various pulse shapes with different rise, hold and fall time have been studied the pulse of hold time 70 ns and rise and fall time of 5 ns gives maximum stable RF power. Device parametric analysis for the different cathode and post-acceleration voltages has also been investigated. With a beam current of 750 A, cathode voltage of 200 kV and post-acceleration voltage of 800 kV, the device provides ~350 MW with ~46% efficiency.

The book examines the market reaction to mergers and acquisitions (M & A) announcements over a period from 2003 to 2015. Mergers and acquisitions continue to be amongst the preferred competitive options available to the companies seeking to grow fast in the rapidly changing global business scenario. M & A as a growth strategy has received attention from developed as well as emerging economies. It has been extensively used by managers as an expansion strategy and also serves as an important instrument for increasing corporate efficiency. Recently, M & A has grown at a rapid pace, creating a need for research to analyze what drives this phenomenon and how it affects firms and markets. As such, this book evaluates the impact of M & A on short-term abnormal returns as well long-term financial performance. It also assesses the management view concerning the motives for undertaking M & A. In addition, the book investigates the corporate governance practices of the acquiring firms and their impact on the short- term as well as long- term performance of those firms.

In this paper, a bi-frequency magnetically insulated line oscillator (MILO) was proposed and designed. The bi-frequency MILO proposed has two axially partitioned slow-wave interaction structures (SWS) and the second SWS is dielectric-loaded to create the frequency shift in the resonant frequency. The conventional MILO device design methodology was followed along with two SWSs separated by a segregation cavity. The dispersion relation of the dielectric-loaded SWS was calculated using an equivalent circuit approach. Furthermore, the cold analysis was carried out to find the energy stored in the different SWSs to validate the device oscillation frequency. The beam wave interaction behaviour and device RF output performance were investigated through 3D PIC (Particle-in-cell) simulation for typical diode voltage of 550 kV, and current 48 kA, respectively. Simulation results illustrate that the proposed MILO generates RF peak power of ~3.5 GW at frequencies 3.62 GHz and 3.72 GHz. The conversion efficiency of the device was ~13.25%.