34,851 research outputs found
Asimovian Adaptive Agents
The goal of this research is to develop agents that are adaptive and
predictable and timely. At first blush, these three requirements seem
contradictory. For example, adaptation risks introducing undesirable side
effects, thereby making agents' behavior less predictable. Furthermore,
although formal verification can assist in ensuring behavioral predictability,
it is known to be time-consuming. Our solution to the challenge of satisfying
all three requirements is the following. Agents have finite-state automaton
plans, which are adapted online via evolutionary learning (perturbation)
operators. To ensure that critical behavioral constraints are always satisfied,
agents' plans are first formally verified. They are then reverified after every
adaptation. If reverification concludes that constraints are violated, the
plans are repaired. The main objective of this paper is to improve the
efficiency of reverification after learning, so that agents have a sufficiently
rapid response time. We present two solutions: positive results that certain
learning operators are a priori guaranteed to preserve useful classes of
behavioral assurance constraints (which implies that no reverification is
needed for these operators), and efficient incremental reverification
algorithms for those learning operators that have negative a priori results
Additions to the Hyperaspis Chevrolat (Coleoptera: Coccinellidae) fauna of South American, descriptions of nine new species, and recognition of Hyperaspis pectoralis Crotch as a valid species
Nine new species of Hyperaspis from various South American localities are described, illustrated, and compared with previously described taxa. New taxa are: Hyperaspis luciae, H. corcovado, H. divaricata, H. humboldti, H. mimica, H. praecipua, H. unimaculosa, H. drechseli, and H. esmeraldas. Hyperaspis pectoralis Crotch is recognized as a valid species of Hyperaspis and integrated into the existing classification
Descriptions of the male of Heterodiomus marchali Brèthes and a new species of Chilean Heterodiomus Brèthes (Coleoptera: Coccinellidae: Scymninae: Diomini)
Additions to the classification of South American Diomini are provided. Male genitalia of Heterodiomus marchali Brèthes are described and Diomus brethesi is newly described
Effects of high and low barometric pressures on susceptibility and resistance to infection Quarterly status report, 1 Apr. - 30 Jun. 1969
Effects of atmospheric pressure on susceptibility and resistance to infectio
Effects of high and low barometric pressures on susceptibility and resistance to infection Quarterly status report, 1 Oct. - 31 Dec. 1968
Effects of high and low barometric pressures on susceptibility and resistance to infection in mic
Effects of high and low barometric pressures on susceptibility and resistance to infection Quarterly status report, 1 Jul. - 30 Sep. 1969
Atmospheric pressure effects on mice resistance to bacterial or virus infection
A comparative study of herbage intake, ingestive behaviour and diet selection, and effects of condensed tannins upon body and wool growth in lambs grazing Yorkshire fog (Holcus lanatus) and annual ryegrass (Lolium multiflorum) dominant swards
An experiment was carried out from August to early November 1994 to examine differences in diet selection, herbage intake, grazing behaviour and animal performance between weaned lambs rotationally grazing swards of annual ryegrass (Lolium multiflorum)/white clover (Trifolium repens) and Yorkshire fog (Holcus lanatus)/T. repens with or without Lotus corniculatus. There were four replicate groups of six lambs per treatment. The effects of condensed tannins (CT) on lamb production were assessed by twice-daily oral administration of 10g polyethylene glycol (PEG; molecular weight 4000) to half the lambs on each sward. The Lotus content of all swards was very low, and results are presented here for main sward comparisons meaned over lotus treatments. Overall mean estimates of pre-grazing herbage mass and sward surface height for the annual ryegrass and Yorkshire fog swards respectively, were 5820 v. 4360 +/- 190 kg DM/ha (P , P < 0.01) and liveweight gain (141 v. 120 +/- 4.3 g per lamb per day, P < 0.01), although differences in carcass weight (17.9 v. 18.2 +/- 0.3 kg) and FEC transformed values (9.6 v. 11.0 +/- 06 eggs/g fresh faeces) were not significant. The effects of CT on animal performance were greater in Yorkshire fog swards. CT had no significant effects on diet selection, herbage intake and grazing behaviour patterns
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