The goal of this paper is to study the benefits of hybridizing the CNF SAT Solvers with BDDs. Towards this we define a metric for the level of hybridization based on a tree decomposition of an input CNF. We also present a new linear time algorithm on BDDs, which is useful for efficient conflict analysis in any BDD-based hybrid SAT solver. Experiments on an implementation of our hybrid solver sh...

This paper presents a decision algorithm for the analysis of the stability of a class of planar switched linear systems, modeled by hybrid automata. The dynamics in each location of the hybrid automaton is assumed to be linear and asymptotically stable; the guards on the transitions are hyper planes in the state space. We show that for every pair of an ingoing and an outgoing transition related...

We present a technique based on the use of the quantifier elimination decision procedure for real closed fields and simple theorem proving to construct a series of successively finer qualitative abstractions of hybrid automata. The resulting abstractions are always discrete transition systems which can then be used by any traditional analysis tool. The constructed abstractions are conservative ...

Two families of methods are widely used in data assimilation: the four dimensional variational (4D-Var) approach, and the ensemble Kalman filter (EnKF) approach. The two families have been developed largely through parallel research efforts, and each method has its advantages and disadvantages. It is of interest to combine the two approaches and develop hybrid data assimilation algorithms. This...

This paper presents performance analysis of an adaptive Volterra/Hybrid equalizer in a nonlinear magneto-optic data storage channel. In a data storage system, nonlinear intersymbol interference (ISI) is one of the limiting factors for high storage density. Volterra and Hybrid (combination of linear and Volterra) equalizers are proposed and developed for compensation of nonlinear ISI. The use of...

This paper presents the design and analysis of a new adaptive fuzzy (AF) logic and hybrid (skyhook plus groundhook) control technique applied to a semi-active suspension system of a quarter car mode. The hybrid control is applied because of its very good performance in ride comfort and road handling. Meanwhile, Fuzzy adaptive system is suitable for analysis of stability with non-linear performa...

The use of algorithmic verification and synthesis tools for hybrid systems is currently limited to systems exhibiting simple continuous dynamics such as timed automata or rectangular hybrid systems. In this paper we enlarge the class of systems amenable to algorithmic analysis and synthesis by showing decidability of model checking Linear Temporal Logic (LTL) formulas over discrete time, contro...