Observations have been conducted on the recently discovered short period pulsar PSR 1951+32 in the radio nebula CTB 80 in an attempt to detect pulsed infrared emission. A strong upper limit is placed on any pulsed, infrared component below that expected from a formally proposed optical candidate for the pulsar. This limit is consistent with proposed scaling laws for high-energy emission.

Modular programs are built as a combination of separate modules, which may be developed and veriied separately. Therefore, in order to reason over such programs, compositionality plays a crucial role: the semantics of the whole program must be obtainable as a simple function from the semantics of its individual modules. In the eld of logic programming, the need for a compositional semantics has...

Extreme Value theory is part and parcel of any study of order statistics in one-dimension. Our aim here is to consider such large sample theory for the maximum distance to the origin, and the related maximum “interpoint distance,” in multi-dimensions. We show that for the spherically symmetric families of densities, these statistics have a Gumbel type limit, generalizing several existing result...

In this article we calculate the n-string braid groups of certain noncontractible graphs. We use techniques from the work of A. Abrams, F. Connolly and M. Doig combined with Van Kampen’s Theorem to prove these results.

We investigate axiomatizations of Kripke’s [18] theory of truth based on the Strong Kleene evaluation scheme for treating sentences lacking a truth value. Feferman’s axiomatization KF formulated in classical logic is an indirect approach, because it is not sound with respect to Kripke’s semantics in the straightforward sense; only the sentences provably true in KF are valid in Kripke’s partial ...

We propose a combination of Bochvar’s strict three-valued logic, McCarthy’s sequential three-valued logic, and process algebra via the conditional guard construct. This combination entails the introduction of a new constant meaningless in process algebra. We present an operational semantics in SOS-style, and a completeness result for ACP with conditional guard construct and the proposed logic.

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