This paper presents a new search procedure to identify unsatisfiable (UNSAT) sub-formulas from UNSAT CNF instances. Our approach searches for clauses involved in conflicts and analyzes them to incrementally build an UNSAT core. Experiments have been conducted extensively, using a prototype implementation of our strategy. Results demonstrate that the incremental nature of our technique allows to...

Quantum cognition is an emerging field that uses mathematical principles of quantum theory to help formalize and understand cognitive systems and processes. The topic on the potential of using quantum theory to build models of cognition (Volume 5, issue 4) introduces and synthesizes its new development through an introduction and six core articles. The current issue presents 14 commentaries on ...

We study the problem of designing the hyperlink structure of a website to maximize the revenue generated by a random walk on the website. We ask if each webpage is controlled by an autonomous agent, is it possible to give all coalitions incentive to cooperate and build the optimal hyperlink design? We show that the optimal design is in the core of the transferable utility game. For non-transfer...

infection with hepatitis c virus (hcv) is a worldwide problem. among hcv proteins, core antigen (ag), besides its importance for diagnostic application is a prime candidate for component of a vaccine. herein, we report results of studies on production of the hydrophilic domain of core ag (2-122) in native conformation by an arabinose induction system in e.coli and the primary characterization o...

The paper presents the results of investigations concerning the possibility of using programmable logic devices (FPGA) to build virtual multi-core processors dedicated specifically towards particular applications. The paper shows the designed architecture of a multi-core processor specialized to perform a particular task, and it discusses its computational efficiency depending on the number of ...

background: the aim of this work was to study the output factors for linac using different ionization chambers and build up caps. materials and methods: output factors were measured for open square fields (3 × 3 cm to 40 × 40 cm) defined by collimator jaws for 6 and 15 mv photon beams from a varian clinac 2100c accelerator were measured. the measurements in air were performed using compact cyli...

Application portals, or Problem Solving Environments (PSEs), provide user environments that simplify access and integrate various distributed computational services for scientists working on particular classes of problems. Specific application portals are typically built on common sets of core services, so reusability of these services is a key problem in PSE development. In this paper we addre...

We present an implementation in Haskell of a dependently-typed lambda calculus that can be used as the core of a programming language. We show that a dependently-typed lambda calculus is no more difficult to implement than other typed lambda calculi. In fact, our implementation is almost as easy as an implementation of the simply typed lambda calculus, which we emphasize by discussing the modif...

The aim of this study was to compare three types of post and core systems by analyzing the stress magnitude within the root. To this end, two-dimensional photoelastic simulation models of endodontically treated maxillary central incisors were fabricated. Three different types of post and core systems were selected for this study: composite resin post and core, composite resin core in combinatio...