This paper describes a representation of the dynamics of human walking action for the purpose of person identification and classification by gait appearance. Our gait representation is based on simple features such as moments extracted from video silhouettes of human walking motion. We claim that our gait dynamics representation is rich enough for the task of recognition and classification. The...

This study describes the daily activity in a simulated high tide situation of four species of hermit crabs (Pagurus criniticornis, Clibanarius antillensis, C. sclopetarius, and C. vittatus) that coexist in an intertidal flat in southeastern Brazil. Observations were done in two-hour intervals during two subsequent days (48 h) in three replicate pools with thirty crabs each. Among species (betwe...

Responses to innocuous stimuli often habituate with repeated stimulation, but the mechanisms involved in dishabituation are less well studied. Chan et al. (2010b) found that hermit crabs were quicker to perform an anti-predator withdrawal response in the presence of a short-duration white noise relative to a longer noise stimulus. In two experiments, we examined whether this effect could be exp...

We evaluate HERMIT, an OWL2 reasoner, on a set of test cases that emerge from an unusual but very practical way of using Description Logics (DLs). In the field of reasoning about actions, the projection problem is an elemental problem that deals with answering whether a certain formula holds after doing a sequence of actions starting from some initial states represented using an incomplete theo...

We study a dynamic coordination process in which agents are uncertain about the actions of their fellow agents, and anticipate strategically relevant information. Because of the uncertainty and learning, (ir)reversibility of actions has important strategic consequences. We find that the reversibility option can either enhance or hamper efficient coordination, and we characterize the direction o...

Many studies have focused on the effects of anthropogenic noise on animal communication, but only a few have looked at its effect on other behavioural systems. We designed a playback experiment to test the effect of noise on predation risk assessment. We found that in response to boat motor playback, Caribbean hermit crabs (Coenobita clypeatus) allowed a simulated predator to approach closer be...

Faceted search is the de facto query paradigm in e-commerce and it has been recently adapted for the Semantic Web. In this demonstration we present our faceted search system SemFacet and show how it can enhance access to RDF and OWL 2 datasets and OWL 2 ontologies in the domain of life sciences. SemFacet combines keyword and faceted search and it is based on a solid theory, in particular it emp...

Two species of the pagurid hermit crab genus Lophopagurus McLaughlin, 1981 are reported herein. Lophopagurus (Lophopagurus) minimus n. sp., described on the basis of two females from Tuamotu Archipelago, French Polynesia, appears closest to L. (L.) nanus (Henderson, 1888), but is easily distinguished from the latter by the different shape of the ocular peduncles and the less developed armature ...

A number of ontology reasoners have been developed for reasoning over highly expressive ontology languages such as OWL DL and OWL 2 DL. Such languages have, as a consequence of high expressivity, high worst-case complexity. Therefore, reasoning tasks such as classification sometimes take considerable time on large and complex ontologies. In this paper, we carry out a comprehensive comparative s...