In this paper, we outline a theory of referential accessibility called Veins Theory (VT). We show how VT addresses the problem of "left satellites", currently a problem for stack-based models, and show that VT can be used to significantly reduce the search space for antecedents. We also show that VT provides a better model for determining domains of referential accessibility, and discuss how VT...

In this paper, we consider the problem of constructing hierarchies of nonlinear control systems that preserve reachability properties, and, in particular, local accessibility. In this hierarchical framework, showing local accessibility of the higher level abstracted model of the nonlinear control system is equivalent to showing local accessibility of the, more detailed, lower level model. Hiera...

Physical layer security is a useful tool to prevent illegal wiretapping confidential information. In this paper, we consider generalized model of conventional physical security, referred as hierarchical information accessibility (HIA). A main feature the HIA that network has hierarchy in access, wherein decoding feasibility determined by each user’s priority. Under model, formulate sum secrecy ...

The process of evaluating a built environment for accessibility is known as “accessibility assessment.” Determining accessibility is closely related to the problem of determining possible motions of a specific kinematic structure – given an environment and a mobile device, how much of the environment is accessible? Given these similarities, here the accessibility assessment process is reformula...

C. A. R. Hoare, N. Wirth, E. W. Dijkstra, and some others active in structured programing have described and tacitly recommended a hierarchical accessibility of passed data in structured programing (see for example, References 11 and 26). This fits well, they and others indicate, with both the theory and the practice of structured programing (see for example, References 15, 18, 19, and 25). Thi...

The Future Operations Centre Analysis Laboratory (FOCAL) at Australia’s Defence Science and Technology Organisation (DSTO) is aimed at exploring new paradigms for situation awareness (SA) and command and control (C2) in military command centres, making use of new technologies developed for virtual reality and real-time 3D animation. Recent work includes the conceptual design and prototype devel...

We consider a two-dimensional quantum control system evolving under an entropyincreasing irreversible dynamics in the semigroup form. Considering a phenomenological approach to the dynamics, we show that the accessibility property of the system depends on whether its evolution is assumed to be positive or completely positive. In particular, we characterize the family of maps having different ac...

Sprawl opponents have blamed sprawl for weakening linkages among the residents and social capital but there is a lack of empirical evidence to support their argument. This study examines the relationship between the county sprawl index and social-capital factors from the 2000 Social Capital Community Benchmark Survey data. Using 3-level hierarchical models, this study shows that for the US, urb...