Matching Items (7)

Composing Hybrid Discrete Event System and Cellular Automata Models

Description

Hybrid system models - those devised from two or more disparate sub-system models - provide a number of benefits in terms of conceptualization, development, and assessment of dynamical systems. The

Hybrid system models - those devised from two or more disparate sub-system models - provide a number of benefits in terms of conceptualization, development, and assessment of dynamical systems. The decomposition approach helps to formulate complex interactions that are otherwise difficult or impractical to express. However, hybrid model development and usage can introduce complexity that emerges from the composition itself.

To improve assurance of model correctness, sub-systems using disparate modeling formalisms must be integrated above and beyond just the data and control level; their composition must have model specification and simulation execution aspects as well. Poly-formalism composition is one approach to composing models in this manner.

This dissertation describes a poly-formalism composition between a Discrete EVent System specification (DEVS) model and a Cellular Automata (CA) model types. These model specifications have been chosen for their broad applicability in important and emerging domains. An agent-environment domain exemplifies the composition approach. The inherent spatial relations within a CA make it well-suited for environmental representations. Similarly, the component-based nature of agents fits well within the hierarchical component structure of DEVS.

This composition employs the use of a third model, called an interaction model, that includes methods for integrating the two model types at a formalism level, at a systems architecture level, and at a model execution level. A prototype framework using DEVS for the agent model and GRASS for the environment has been developed and is described. Furthermore, this dissertation explains how the concepts of this composition approach are being applied to a real-world research project.

This dissertation expands the tool set modelers in computer science and other disciplines have in order to build hybrid system models, and provides an interaction model for an on-going research project. The concepts and models presented in this dissertation demonstrate the feasibility of composition between discrete-event agents and discrete-time cellular automata. Furthermore, it provides concepts and models that may be applied directly, or used by a modeler to devise compositions for other research efforts.

Contributors

Agent

Created

Date Created
  • 2009

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Zooarchaeological and taphonomic analyses of Pleistocene vertebrate fauna from the Middle and Later Stone Age occupations at Contrebandiers Cave, Atlantic coast, Morocco

Description

This dissertation research describes the hunting behavior of early modern humans through the analysis of vertebrate faunal remains from Contrebandiers Cave, Morocco. Contrebandiers Cave is located in the town of

This dissertation research describes the hunting behavior of early modern humans through the analysis of vertebrate faunal remains from Contrebandiers Cave, Morocco. Contrebandiers Cave is located in the town of Témara and is roughly 250 meters from the current shoreline of the Atlantic Ocean. The cave was excavated in the 1950s and 1970s by l’Abbé Roche, and again starting in 2007 by Dibble and El Hajraoui with total station plotting of finds. Contrebandiers Cave contains Middle Stone Age (MSA) deposits dated to Marine Isotope Stages (MIS) 5e, 5d and 5c, ~120,000 to ~96,000 years ago. The Later Stone Age (LSA) deposits are dated to MIS 2, ~20,000 years ago. The entirety of the ~12,000 vertebrate faunal remains from Dibble and El Hajraoui’s excavation were analyzed for taxonomic and taphonomic identification.

A total of 67 vertebrate taxa were identified and include ungulates, carnivores, lagomorphs, birds, tortoises, snakes and fish. The faunal remains from Contrebandiers Cave preserve surface modification that indicates both humans and carnivores acted as agents of prey accumulation. Skeletal element representation and surface modification of ungulate remains suggest that humans had primary access to small, medium and large-bodied prey. In the MSA levels, carnivore skeletal remains preserve surface modification that is interpreted as being indicative of behavior associated with skinning for fur removal.

The vertebrate faunal remains from MIS 5e and 5d indicate that humans were hunting grazers and mixed feeders from open habitats and suids from mixed habitats. The faunal remains from MIS 5c indicate that humans focused less on suids and more on mixed feeders from open habitats. The vertebrate faunal remains from MIS 2 reveal humans hunting grazers from dry, open habitats. This research provides a description of human hunting behavior in North Africa, and contributes to our understanding of early modern human behavior prior to dispersal out of Africa.

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Agent

Created

Date Created
  • 2018