Sliding-mode amplitude control techniques for harmonic oscillators

This thesis investigates both theoretical and implementation-level aspects of switching- feedback control strategies for the development of voltage-controlled oscillators. We use a modified sliding-mode compensation scheme based on various norms of the system state to achieve amplitude control for wide-tuning range oscillators. The proposed controller provides amplitude control at minimal cost in area and power consumption. Verification of our theory is achieved with the physical realization of an amplitude controlled negative-Gm LC oscillator. A wide-tuning range RF ring oscillator is developed and simulated, showing the effectiveness of our methods for high speed oscillators. The resulting ring oscillator produces an amplitude controlled sinusoidal signal operating at frequencies ranging from 170 MHz to 2.1 GHz. Total harmonic distortion is maintained below 0:8% for an oscillation amplitude of 2 Vpp over the entire tuning range. Phase noise is measured as -105.6 dBc/Hz at 1.135 GHz with a 1 MHz offset

Racial Desegregation in Prisons

This article examines the history, law, and research on racial desegregation in American prisons. It focuses on the 2005 U.S. Supreme Court case of Johnson v. California, in which the Court held that prison administrators cannot racially segregate inmates unless under extraordinary circumstances to maintain the security of inmates, staff, and institutions. This article also examines evidence on attitudes and outcomes of racial desegregation in prisons. It ends with a discussion of racial desegregation mandates and policy change in prison organizations