The order parameter model based on the parametric Ginzburg-Landau equation is used to describe high acceleration patterns in the vibrated layer of granular material. At large amplitude of driving both hexagons and interfaces emerge. Transverse instability, leading to the formation of ‘‘decorated’’ interfaces and labyrinthine patterns, is found. Additional subharmonic forcing leads to controlled...

We consider communication structures for event ordering algorithms in distributed environments where information ows only in one direction. Example applications are multilevel security and hierarchical databases. Although the most general one-directional communication structure is a partial order, partial orders do not enjoy the property of being consistently-ordered, a formalisation of the not...

This paper describes a parallel implementation of a texture segmentation algorithm. The algorithm uses a Pearl Bayes Network (PBN) to combine evidence for the location of urban regions in airborne infra-red linescan images and for the location of driveable regions in autonomous land vehicle imagery. A multilevel PBN approach is introduced and followed by an example which is used to illustrate t...

The security of a network configuration is based not just on the security of its individual components and their direct interconnections, but also on the potential for systems to interoperate indirectly across network routes. Such interoperation has been shown to provide the potential for cascading paths that violate security, in a circuitous manner, across a network. In this paper we show how ...

It has been found that the L* function defined in the CIELAB color space is not suitable to predict the human visual perception of modulated patterns at high spatial frequencies. For example, in multilevel haiftoning (multitoning), when output levels are equally spaced in L , it has been observed that the visibility ofthe resulting multitone patterns is not uniform across different parts of the...

14 the multilevel security constraints that precisely characterize the validity of mul-tilevel relational databases. Our model-theoretic semantics is consistent with, and extends, the Bell-LaPadula model. Compared with existing approaches, our model-theoretic semantics maximizes believability without compromising integrity or introducing ambiguity. Contrary to the claim that integrity and secre...

The paper is dedicated to the phenomenon of accentuation on multiple narrative levels. Accentuation is a textual device that indicates the elements of narrative that have to be memorized by readers. It is different from the well known notion of foregrounding, as accentuation does not violate the norm, but, on the contrary, is in itself conventional. While foregrounding draws readers’ attention ...

The ability to process electronic information of multiple security classifications has long been a goal of warfighters. The process of Fusing National information at levels above Top Secret (TS) with the tactical picture being generated onboard the ship has been greatly improved in recent years, but remains primarily a manual one with the onboard Ship Sensitive Equipment Space (SSES) and off-bo...

In this paper we study a denotational model for a discrete-time version of CSP. We give a compositional semantics for the language. The model records refusal information at the end of each time unit; we believe this model to be simpler than existing models. We also show that the model is fully abstract: equivalence in the model corresponds to the natural equivalence of may testing; and all memb...