We study time-reversal symmetry in dynamical systems with finite phase space, with applications to birational maps reduced over finite fields. For a polynomial automorphism with a single family of reversing symmetries, a universal (i.e. map-independent) distribution function R(x) = 1 − e−x(1 + x) has been conjectured to exist, for the normalized cycle lengths of the reduced map in the large fie...

Decentralized logical coordinate systems have been proposed as a means of estimating network distances. These systems have widespread usage in p2p networks, ranging from neighbor selection to replica placement. Unfortunately, these systems are vulnerable to even a small number of malicious nodes lying about their coordinates or measurements. In this paper, we introduce Veracity, a fully decentr...

Automated Provisioning of Back-end Databases in Shared Dynamic Content Server Clusters Gokul Soundararajan Master of Applied Science Graduate Department of Electrical and Computer Engineering University of Toronto 2005 This thesis describes Vivaldi, a self-configuring architecture for scaling the database tier of dynamic content web services. We design an automatic and transparent provisioning ...

In this work, a wideband airborne reflector-based ground penetrating radar (GPR) is designed and proposed. The proposed GPR consists of 15 discrete panels, each panel supported by single multi-rotor unmanned aerial vehicle (UAV). A lightweight, Vivaldi antenna was developed as the feed structure. operates within frequency range 100-500 MHz has bandwidth 387 MHz. will possess penetration depth 2...

This paper presents a scalable and compact 3D-printed Vivaldi antenna array with liquid cooling for the frequency band from 24.0 to 29.5 GHz. The proposed design consists of an 8 × commercial beam-forming ICs on antenna-side PCB efficient area utilization that enables high integration level. Scalable is integrated into array. measured temperature water during operation remains below 50°C. simul...

Many wideband applications, e.g., microwave imaging of the head, require low-frequency (~1–6 GHz) operation using small antennas. Vivaldi antennas are extensively used in multifarious applications; however, physical dimensions antenna become very large for covering bands. Hence, miniaturization antennas, while maintaining proper matching and radiation characteristics, is essential these applica...