The Petri Box Calculus (PBC) consists of an algebra of box expressions, and a corresponding algebra of boxes (a class of labelled Petri nets). A compo- sitional semantics provides a translation from box expressions to boxes. The synthesis problem is to provide an algorithmic translation from boxes to box expressions. The axiomatisation problem is to provide a sound and complete axiomatisation for the fragment of the calculus under consideration, which captures a particular notion of equivalence for boxes. There are several alternative ways of defining an equivalence notion for boxes, the strongest one being net isomorphism. In this thesis, the synthesis and axiomatisation problems are investigated for net semantic isomorphism, and a slightly weaker notion of equivalence, called duplication equivalence, which can still be argued to capture a very close structural similarity of con- current systems the boxes are supposed to represent. In this thesis, a structured approach to developing a synthesis algorithm is proposed, and it is shown how this may be used to provide a framework for the production of a sound and complete axiomatisation. This method is used for several different fragments of the Petri Box Calculus, and for gener- ating axiomatisations for both isomorphism and duplication equivalence. In addition, the algorithmic problems of checking equivalence of boxes and box expressions, and generating proofs of equivalence are considered as extensions to the synthesis algorithm.

Thesis (MEng)--University of South Australia, 1997

Thesis (M.S.)--Ohio University, August, 2000. / Title from PDF t.p.

Thesis (M.S.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed January 21, 2009) Includes bibliographical references.

Thesis (M.S.)--Ohio University, March, 1995. / Title from PDF t.p.

Thesis (M. Phil.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 99-102).

Thesis (M. Sc.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 63-67.

PURPOSE: To characterize the distribution of white matter neurons (WMNs) positive for perineuronal nets (PNNs) in the adult monkey. WMNs are a mixed population of excitatory and inhibitory neurons. They have an important role in axon guidance during cortical development, but their role in the adult brain is less understood. In vitro and in vivo experiments provide evidence that WMNs are incorporated into cortical circuitry. The majority of investigations in the adult, however, have focused on regional variations in overall density, or on characterization of morphological and neurochemical subtypes. The present study was motivated by the observation that some WMNs exhibit PNNs in adult monkey. Since PNNs are associated with plasticity in younger animals, their occurrence with some WMNs might be functionally significant. METHODS: PNNs were visualized, at the light microscopic level, by WFA staining in three adult macaque brains. Density of WFA positive WMNs was scored at three anterior-posterior levels (frontal, mid-hemispheric, and occipital), and compared with overall density of WMNs, as visualized by immunocytochemistry for NeuN. Quantitation of WFA+ neurons and neuron morphology were analyzed via light microscopy. Soma size and appearance, and dendritic length were recorded and measured. RESULTS: On the basis of soma size and proximal dendritic shape, several types of WFA+ WMNs were provisionally identified, consistent with previous reports in the literature. Subpopulation densities were of highest density in mid-cortical areas and lowest quantities at occipital, matching previous studies. Morphological measurements suggested a heterogeneous neuron population through soma measurements and dendrite orientation. Soma sizes exhibited a range of circularity and size (10 µm – 30 µm). Dendrites were stained beyond the “proximal” area, including intermediate areas beyond the first branch, and up to 500 µm. CONCLUSIONS: A small population of WMNs are coated by PNNs in adult monkey. On the basis of morphology, these might be further subdivided, but combined studies with other markers would be needed. Future studies might investigate age- or pathology-related changes in the density and subtypes of WMNs that express PNNs in human or nonhuman primates. We speculate that these WMNs might have functional specializations, perhaps similar to the plasticity effects documented for PNNs in early development.

The aggregation hierarchy is one of the most significant data abstraction mechanisms that emerged as a result to semantic extensions to traditional systems analysis and design methods. The way inheritance works in this hierarchy is studied in this thesis. Special emphasis is placed on the behaviour of objects which are related via an aggregation hierarchy. A framework is introduced for capturing the behaviour of a system from the respective behaviour(s) of its components. This framework is based on a 3-level behaviour modelling hierarchy. One of the most significant contributions of this framework is the ability to apply inter-object interactions when building a behaviour model of a system. These interactions are significant in that they can yield totally distinct models of the systems functionality. Some of the notions that are supported by the behaviour modelling framework include unreachable and transient states, transition chains (cascades) and concurrency. The framework also enables the creation of behaviour model (semantic) hierarchies, wherein certain facets of the systems behaviour or functionality can be hidden (abstracted out) in a gradual fashion that suits the requirements of the problem domain. This creates what is effectively, distinct views of the behaviour or functionality of the system. The notions and concepts that are introduced here are verified and presented in a comprehensive case study that shows what can be achieved using these ideas. Suggestions are also made for future work which can help overcome some of the limitations introduced throughout this research.

Indiana University-Purdue University Indianapolis (IUPUI) / The idea of emission control is not new. Different industries have been putting in a lot of effort to limit the harmful emissions and support the environment. Keeping our earth green and safe for upcoming generations is our responsibility. Many cement plants have been shut down in recent years on account of high emissions. Controlling SO2, NOx and CO emissions using the Petri net models is an effort towards the clean production of cement. Petri nets do not just give a pictorial representation of emission control, but also help in designing a controller. A controlled Petri net can be potentially implemented to control the process parameters. In Chapter 2, we discuss the Petri nets in detail. In Chapter 3, we explain the modeling of emissions using the Petri nets. A controlled emission model is given in Chapter 4. A general Petri net model is considered to design the controller, which can be easily modified depending on the specific requirements and type of kiln in consideration. The future work given at the end is the work in progress and a neural network model will likely be integrated with the Petri net model.