João M. Silva

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This paper introduces GRASP (Generic seaRch Algorithm for the Satisfiability Problem), a new search algorithm for Propositional Satisfiability (SAT). GRASP incorporates several search-pruning techniques, some of which are specific to SAT, whereas others find equivalent in other fields of Artificial Intelligence. GRASP is premised on the inevitability of(More)
In this paper we describe a new model and algorithm for computing minimum-size prime implicants of Boolean functions. The computation of minimum-size prime implicants has several applications in different areas, including Electronic Design Automation (EDA), Non-Monotonic Reasoning, Logical Inference, among others. For EDA, one significant and immediate(More)
In this paper we describe how several search pruning concepts, commonly used in algorithms for solving covering problems, can be incorporated in algorithms for propositional satisfiability (SAT). In particular, we show that the concepts of row dominance and matrix partitioning, commonly used for solving unate and binate covering problems, can be naturally(More)
Antimicrobial peptides (AMPs) are part of the innate immune system and are generally defined as cationic, amphipathic peptides, with less than 50 amino acids, including multiple arginine and lysine residues. The human cathelicidin antimicrobial peptide LL37 can be found at different concentrations in many different cells, tissues and body fluids and has a(More)
This work studied the physical immobilization of a commercial laccase on bacterial nanocellulose (BNC) aiming to identify the laccase antibacterial properties suitable for wound dressings. Physico-chemical analysis demonstrates that the BNC structure is manly formed by pure crystalline Iα cellulose. The pH optimum and activation energy of free laccase(More)
Among the strategies to improve a material's hemocompatibility, pre-coating with the tripeptide Arg-Gly-Asp (RGD) is used to favor endothelialization thus lowering thrombogenicity. The blood compatibility of native and RGD-modified bacterial cellulose (BC) was studied in this work for the first time. The plasma recalcification time and whole blood clotting(More)
Minimum-size prime implicants of Boolean functions find application in many areas of Computer Science including, among others, Electronic Design Automation and Artificial Intelligence. The main purpose of this paper is to describe and evaluate two fundamentally different modeling and algorithmic solutions for the computation of minimum-size prime(More)
Redundancy identification and removal is a critical step that typically follows logic synthesis or optimization. In principle, it should be possible to restrict the transformations applied by synthesis and optimization algorithms to those that preserve testability. In practice, however, few, if any, synthesis programs can guarantee the irredundancy of the(More)
For a significant number of electronic systems used in safety-critical applications circuit testing is performed periodically. For these systems, power dissipation due to BuiltIn Self Test (BIST) can represent a significant percentage of the overall power dissipation. One possible solution to address this problem consists of test pattern reordering with the(More)