One of the basic requirements of an intelligent agent is the ability to represent and reason about space. While there are a number of approaches for achieving this goal, the recent gains in efficiency of the Satisfiability approach have made it a popular choice. Modern propositional SAT solvers are efficient for a wide variety of problems. However, conversion to propositional SAT can sometimes ...

Currently, the most effective complete SAT solvers are based on the DPLL algorithm augmented by clause learning. These solvers can handle many real-world problems from application areas like verification, diagnosis, planning, and design. Without clause learning, however, DPLL loses most of its effectiveness on real world problems. Recently there has been some work on obtaining a deeper understa...

| Since most digital phase-locked loops (DPLLs) used in digital data transmission receivers require both fast acquisition of input frequency and phase in the beginning and substantial jitter reduction in the steady-state, the DPLL loop bandwidth is preferred to being adjusted accordingly. In this paper, a bandwidth adjusting (adaptive) algorithm is presented, which allow both fast acquisition a...

Radar Signal Processing has been an interesting area of research for realization of programmable digital signal processor using VLSI design techniques. Digital Signal Processing (DSP) algorithms have been an integral design methodology for implementation of high speed application specific real-time systems especially for high resolution radar. CORDIC algorithm, in recent times, is turned out to...

A 12-bit Vernier ring time-to-digital converter (TDC) with time resolution of 8 ps for digital-phase-locked-loops (DPLL) is presented. This novel Vernier ring TDC places the Vernier delay cells and arbiters in a ring format and reuses them for the measurement of the input time interval. The proposed TDC thus achieves large detectable range, fine time resolution, small die size and low power con...

We consider the performance of a number of DPLL algorithms on random 3-CNF formulas with n variables and m = rn clauses. A long series of papers analyzing so-called “myopic” DPLL algorithms has provided a sequence of lower bounds for their satisfiability threshold. Indeed, for each myopic algorithm A it is known that there exists an algorithm-specific clause-density, rA, such that if r < rA, th...

SAT solvers have proved to be very efficient in verifying the correctness of automotive product documentations. However, in many applications a car configuration has to be optimized with respect to a given objective function prioritizing the selectable product components. Typical applications include the generation of predictive configurations for production planning and the reconfiguration of ...

DPLL During search, DPLL states are pairs M ||F where M is a truth assignment F is a set of clauses (problem clauses + learned clauses) The truth assignment is a list of literals: either decision literals (guesses) or implied literals (by unit propagation). If literal l is implied by unit propagation from clause C ∨ l, then the clause is recorded as the explanation for l. This is written lC∨l i...