Toward Comprehensive Specification of Distributed Systems

A new approach to modelling distributed systems is presented. It uses sequential processes and event synchronization as building blocks to construct a cohesive picture of the interdependent requirements for the functionality, architecture, scheduling policies, and performance attributes of a distributed system. A language called CSPS (an extension of Hoare\u27s CSP) is used in the illustration of the approach. Employing CSP as a base allows modelled systems to be verified using techniques already developed for verifying CSP programs and leads to the emergence of a uniform incremental strategy for verifying both logical and performance properties of distributed systems. Several small distributed systems have been modelled using this approach. These exercises enabled us to evaluate the notation system and to gain some expertise on how to approach the specification of distributed systems. This paper describes one of the models and the modelling strategy that has emerged from these exercises

The Naked Truth: The Face and Body Sensitive N170 Response Is Enhanced for Nude Bodies

Recent event-related potential studies have shown that the occipitotemporal N170 component - best known for its sensitivity to faces - is also sensitive to perception of human bodies. Considering that in the timescale of evolution clothing is a relatively new invention that hides the bodily features relevant for sexual selection and arousal, we investigated whether the early N170 brain response would be enhanced to nude over clothed bodies. In two experiments, we measured N170 responses to nude bodies, bodies wearing swimsuits, clothed bodies, faces, and control stimuli (cars). We found that the N170 amplitude was larger to opposite and same-sex nude vs. clothed bodies. Moreover, the N170 amplitude increased linearly as the amount of clothing decreased from full clothing via swimsuits to nude bodies. Strikingly, the N170 response to nude bodies was even greater than that to faces, and the N170 amplitude to bodies was independent of whether the face of the bodies was visible or not. All human stimuli evoked greater N170 responses than did the control stimulus. Autonomic measurements and self-evaluations showed that nude bodies were affectively more arousing compared to the other stimulus categories. We conclude that the early visual processing of human bodies is sensitive to the visibility of the sex-related features of human bodies and that the visual processing of other people's nude bodies is enhanced in the brain. This enhancement is likely to reflect affective arousal elicited by nude bodies. Such facilitated visual processing of other people's nude bodies is possibly beneficial in identifying potential mating partners and competitors, and for triggering sexual behavior