Standard approachs to belief change assume that the underlying logic contains classical propositional logic. Recently there has been interest in investigating approaches to belief change, specifically contraction, in which the underlying logic is not as expressive as full propositional logic. In this paper we consider approaches to belief contraction in Horn knowledge bases. We develop two broa...

Horn description logics (Horn-DLs) have recently started to attract attention due to the fact that their (worst-case) data complexities are in general lower than their overall (i.e. combined) complexities, which makes them attractive for reasoning with large ABoxes. However, the natural question whether Horn-DLs also provide advantages for TBox reasoning has hardly been addressed so far. In thi...

This paper presents a framework for relevance-based belief change in propositional Horn logic. We firstly establish a parallel interpolation theorem for Horn logic and show that Parikh’s Finest Splitting Theorem holds with Horn formulae. By reformulating Parikh’s relevance criterion in the setting of Horn belief change, we construct a relevance-based partial meet Horn contraction operator and p...

We extend the knowledge compilation map introduced by Darwiche and Marquis with three influential propositional fragments, the Krom CNF one (also known as the bijunctive fragment), the Horn CNF fragment and the affine fragment (also known as the biconditional fragment) as well as seven additional languages based on them, and composed respectively of Krom or Horn CNF formulas, renamable Horn CNF...

BACKGROUND Pregnancy in the rudimentary uterine horn is an extremely rare clinical condition. Treatment includes surgical removal of the rudimentary horn. METHODS A rudimentary horn pregnancy was reported that occurred after intrauterine insemination. Similar cases treated with laparoscopic surgery reported in the peer-reviewed journals were reviewed as well. RESULTS Pregnancy in the right ...

Rudimentary horn is one of the rarest congenital uterine anomalies and consists of a relatively normal appearing uterus on one side with a rudimentary horn on the other side. It is difficult to diagnose before surgery and hazardous to maternal life as rupture of pregnant horn result in severe hemoperitoneum. Case of rudimentary horn pregnancy is reported in a lady with history of habitual abort...

The ared horn is modeled assuming that Webster's horn equation is satis ed. Any shape can be assumed for the wavefront within the horn. This paper presents a technique for solving Webster's horn equation as follows: The equation is converted to the form of the Schrodinger wave equation used for one-dimensional particle scattering. The horn characteristics can then be obtained directly in terms...

Multiple input multiple output antenna is the key technology which enables design of 5G networks. In order to achieve desired beam forming and side lobe reduction capabilities, antennas used in MIMO are required feed with signals having different phase amplitude. It possible variable shift attenuation using shifter amplitude limiters. However when these devices between source antenna, they make...

A rectangular pyramidal horn antenna fabricated with tapered dielectric E-plane boundary walls whose inner surface is periodically loaded with thin conducting strips is investigated. For better impedance matching, at the throat region of the horn antenna, 3 cm portion is metallised. The radiation characteristics of this horn antenna are compared with that of an identical conventional horn anten...