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DEVS is a sound formal modeling and simulation (M&S) framework based on generic dynamic system concepts. Cell-DEVS is a DEVS-based formalism intended to model complex physical systems as cell spaces. Time Warp is the most well-known optimistic synchronization protocol for parallel and distributed simulations. This work is devoted to developing new techniques for executing DEVS and Cell-DEVS models in parallel and distributed environments based on the WARPED kernel, an implementation of the Time Warp protocol. The resultant optimistic simulator, called as PCD++, is built as a new simulation engine for CD++, an M&S toolkit that implements the DEVS and Cell-DEVS formalisms. Algorithms in CD++ and the WARPED kernel are redesigned to carry out optimistic simulations using a non-hierarchical approach that reduces the communication overhead. The message-passing paradigm is analyzed using a high-level abstraction called wall clock time slice. A two-level user-controlled state-saving mechanism is proposed to achieve efficient and flexible state saving at runtime. This mechanism is integrated with both the copy state-saving and periodic state-saving strategies to realize a hybrid technique that gives simulator developers the full power to dynamically choose the best possible

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The complexity of agents, their environment, and the interaction between agents and environment suggest that experimental testing represents a major research effort in the area of multi-agent systems. However, the development of methods and tools supporting systematic experiments with agents has not found the expected attention. For testing agents, developers often resort to handcrafted solutions developed from scratch. The proposed Grand Challenge is aimed at developing modeling and simulation methods based on theoretical foundations that allow a systematic and comfortable testing of multi-agent systems and to firmly rooting simulation within the emerging area of agentoriented software engineering. The endeavor provides plentifully technological and interdisciplinary challenges.

The development of simulation models for complex systems can be difficult and timeconsuming; therefore, model reuse is of high value to model designers. To be able to reuse modeling components it is important to know the context within which a given component was developed. Experimental Frames are useful for capturing this context. DEVS is a formal M&S framework that supports a hierarchical and modular development of models. This work presents an architecture for an internet based repository of re-usable DEVS models and their Experimental Frames. The proposed architecture uses Experimental Frames to capture the context for the models and allow the sharing of DEVS experiments. It specifies the storage entities required for such a repository, including their contents and relationships; it allows for an ‘open source ’ repository of DEVS models and experiments to be built; and it presents a small step towards enabling collaboration between different DEVS simulation tools. iii ACKNOWLEDGEMENTS First of all, I thank God the almighty for giving me guidance and the ability and patience to complete this research.

Discrete Event System Specification (DEVS) is a formal modeling and simulation (M&S) framework that supports hierarchical, modular models. DEVS-based M&S environments have been used successfully to understand, analyze, and develop a variety of systems. Some of the environments and systems modeled with DEVS are difficult to replicate and analyze; on the other hand, some others are populated with small, embedded devices that perform critical operations with dedicated hardware and software. In both cases the design, simulation and test of these models tend to grow in size and complexity. In each of the development stages, different methods of modeling, implementation and testing are used without any relation among them. CD++ is a modeling and simulation toolkit based on the DEVS formalism. This thesis proposes a modeling, simulation and benchmarking environment based on the CD++ toolkit. Two different tools are presented to the user of the CD++ toolkit: a Benchmarking tool for comparison of the modelling and simulation CD++ tool with other simulators including a benchmarking methodology, and an Integrated Development Environment (IDE) for the conception and construction of models of Real-Time embedded systems, as well as the final implementation and deployment on an

The world of services is evolving towards ‘web-services’, web concerned agents are becoming more and more popular. Agents, as well as many other technologies around the semantic web, have shown an increased maturity through standards and open-source. This tutorial presents these evolutions, positions agents, and introduces the open ecosystem currently in construction under the auspices of agencies. In the later part of tutorial we are talking about the Web Hunting Agent. The goal of this part is to introduce the reader to the basic elements of an intelligent agent, and then apply those elements to a Web search agent to provide the framework for the construction of a simple intelligent Web search agent. An overview of typical artificial intelligence search algorithms will be presented and performance metrics will be discussed. 1.

Agent-based systems are one of the most vibrant and important areas of research and development to have emerged in information technology in the 1990s. Simulation is an important category of applications of multi-agent systems in natural and artificial societies. In this tutorial, first I introduce the characters of agent-based simulation models; then discussed the areas of agent-based simulation applications; after that talk about the challenges existed in agent-based simulation and models as well as solutions; at the end of this tutorial apply the above knowledge into reality and study a concrete agent-based simulation model in detail. 1. Introduction of Agent-based simulation Agents can be interpreted as software systems that are aimed at working autonomously in dynamic and uncertain environments [6]. The interrelations between agents and simulation are manifold [2]. Software agents are used to develop “state of the art” simulation systems on the one hand. On the other hand simulation provides a means for