Formal Scenario Definition Language for Aviation: Aircraft Landing Case Study

Although the importance of scenarios in modeling and simulation has long been well known, there still exists a lack of common understanding and standardized practices in simulation scenario development. This paper proposes a Domain-Specific Language (DLS) to provide a standard scenario specification that will lead to a common mechanism for verifying and executing aviation scenarios, effective sharing of scenarios among various simulation environments, improve the consistency among different simulators and simulations, and even enable the reuse of scenario specifications. Following DSL design practices, the proposed Aviation Scenario Definition Language (ASDL) will provide a well-structured definition language to formally specify complete aircraft landing scenarios. In order to capture the necessary constructs for a simulation scenario, Simulation Interoperability Standards Organization (SISO) Base Object Model (BOM) is adopted as the baseline metamodel. This baseline is extended using the fundamentals of aircraft landing that cover all the domain-related concepts and terminology as constructs. By taking a formal approach in defining aviation scenarios, ASDL aims at providing consistency and completeness checking, and model-to-text transformations capabilities for various targets in the aviation scenario definition domain. The results of this work will be used to develop a graphical modeling environment and automatic means to transform scenario models into executable scenario scripts. The work presented here is the first stepping stone in formal scenario definition in aviation domain

SES and Ecore for Ontology-based Scenario Modeling in Aviation Scenario Definition Language (ASDL)

The Aviation Scenario Definition Language (ASDL) is a domain-specific language proposal which aims to provide a standard aviation scenario specification mechanism and enable the reuse of scenario generation methods among different simulators. This paper presents a model-based scenario development approach that exploits Eclipse Modeling Framework (EMF) core (Ecore) and System Entity Structure (SES) for metamodeling and modeling these elements. The construction of the ASDL metamodel using both platforms is described to illustrate the processes. As a result of comparing two approaches, it is concluded that they follow a similar structure in the hierarchical definition of modeled elements despite there being different toolsets available in each method. Thereby, each metamodel can be easily converted into the other type using transformations. As an application use case, the use of the proposed ontology-based scenario development in the aviation domain is discussed, where a training tool is being developed that utilizes SES/Ecore approach to build a scenario-driven training tool for air traffic controllers

Collaborative Modeling, Simulation and Visualization Framework for Airport Emergency

This paper is part of the DHSS Workshop (International Defense and Homeland Security Simulation). Airport is a highly dynamic environment, turning emergencies into extensively costly and disruptive events with cascaded effects that will adversely affect the entire aviation system. Airports\u27 management and safety divisions exercise precise and case-based procedures to accommodate any possible emergency scenarios. With this regards, airport emergencies have a number of challenges that require better and more adaptive way of addressing. Challenges such as lack of adaptive and customizable simulation-based decision support tools, infeasibility of conducting frequent physical emergency exercises, and the time-critical nature of emergencies in general raise an immediate need for a technology that collaboratively performs modeling, simulation, and visualization to guide first responders throughout the decision-making process. Here we propose a collaborative emergency modeling, simulation and analysis software system that provides an all-in-one simulation technology for enhancing emergency response at airports

Parallel Simulation Techniques for Large-Scale Discrete-Event Models

The Discrete Event System Specification (DEVS) provides a general methodology for hierarchical construction of reusable models in a modular way and has been used to simulate complex systems in a variety of domains. This dissertation addresses software design and performance issues that arise in parallel simulation of large-scale DEVS-based models on multiprocessor cluster architecture. Parallel simulation of complex DEVS-based models requires a robust simulator with low synchronization overhead. Recent researches focused on optimistic parallel simulation of DEVS-based systems. In this research three conservative parallel DEVS protocols (Lower-Bound-TimeStamp (LBTS), Chandy-Misra-Bryant (CMB), and Global-Lookahead-Management (GLM)) are proposed, allowing pure conservative simulation of DEVS-based systems. The protocols are based on the classical Chandy-Misra-Bryant synchronization mechanism, and they extend the DEVS abstract simulator, providing means for lookahead computation and null message distribution. A purely conservative simulator, called CCD++, is presented designed for running large-scale DEVS and Cell-DEVS models in parallel and distributed fashion.An extensive comparative performance analysis is presented, analyzing the performance of CCD++ compared to an optimistic DEVS simulator. Several DEVS-based environmental models with different characteristics are studied. The experiments indicate that the conservative simulator improves performance in terms of execution time, memory usage, operational cost, and system stability for large models. --From the dissertation

Women\u27s Engineering Institute (WEI) at Embry-Riddle Aeronautical University

Embry-Riddle Aeronautical University’s College of Engineering has initiated a Women’s Engineering Institute, which will be a center of excellence on the Daytona Beach Campus to recruit, retain and serve female engineering undergraduate and graduate students. Part of the College’s strategic plan, the WEI will support the College’s goal to increase female enrollment to a minimum of 20% female students by 2016. The University has already committed significant effort and resources to recruiting and retaining female engineering students. The Engineering Fundamentals Department initiated a 2+2 Women in Engineering Mentoring Program in fall 2006, which later became known as the FIRST Program (Female Initiatives: Reaching Success Together). The FIRST program has been a success and the university’s female retention numbers are increasing. But the College of Engineering numbers are stagnant and further assistance, mentoring and academic and social programming is needed to attract more female students to engineering

Data Mining with Cellular Discrete Event Modeling and Simulation

Keywords: Cellular discrete event simulation, Cell-DEVS, data mining, classification Data mining is the process of extracting patterns from data. A main step in this process is referred to as data classification. In this work, we investigate the use of the Cell-DEVS formalism for classifying data. The cells in a Cell-DEVS based grid are individually very simple but together they can represent complex behavior and are capable of self-organization. Three classifier models are implemented using Cell-DEVS. Different simulation scenarios are presented investigating the effect of Von Neumann versus Moore neighborhood in the classifiers’ models. We show that effective classification performance, comparable to those produced by complex data mining techniques, can be obtained from the collective behavior of discrete-event cellular grids. 1

Egress Modeling With Cellular Discrete Event System

The Discrete-Event Modeling and Simulation (DEVS) formalism has been successfully used to model systems whose behavioral state changes based on trigger events. The purpose of this project is to explore the extension of DEVS beyond the modeling of event driven systems, focusing on the application of DEVS to changes in human behavior as driven by emergency events. The objective is to build a modeling and simulation framework for human behavior in emergencies that could easily be extended and built upon in the future. Here we introduce the development of a suite of Cell-DEVS models representing aspects of human behaviors, and the simulation and a detailed analysis of this suite of models. This suite of models explored random and controlled human behaviors, as well as implementing psychological conditions such as herd following. The end state is the development of a repository for these models to serve the DEVS community. --From the paper

Conservative vs. Optimistic Parallel Simulation of DEVS and Cell-DEVS: A Comparative Study

dynamic lookahead, optimistic DEVS. The conservative Parallel DEVS protocol offers a novel approach that allows conservative simulation of DEVSbased PDES systems. The protocol is based on the classical Chandy-Misra-Bryant synchronization mechanism, and it extends the DEVS abstract simulator to provide means for lookahead computation and null-messages. We present a purely conservative simulator, called CCD++, designed for running large-scale DEVS and Cell-DEVS models in parallel and distributed fashion. A comparative performance analysis is presented, analyzing the performance of CCD++ compared to an optimistic DEVS simulator. Several DEVS-based environmental models with different characteristics are studied. The experiments indicate that the conservative simulator improves performance in terms of execution time, memory usage, operational cost, and system stability for very large models. 1

A Performance Evaluation of the Conservative DEVS Protocol in Parallel Simulation of DEVSbased Models

We present the performance evaluation of the Conservative DEVS protocol. This conservative algorithm is based on the classical Chandy-Misra-Bryant (CMB) synchronization mechanism, and extends the DEVS abstract simulator by providing means for lookahead computation and null message distribution. The protocol is integrated into the CD++ simulation toolkit, providing a conservative simulator (named CCD++) for running large-scale DEVS and Cell-DEVS models in parallel and distributed fashion. Throughout the experiments, we analyze four types of metrics, the total execution time, the average blocked time per node, the average number of positive events executed on each node, and the average number of null messages per node. We show a study on three environmental Cell-DEVS models, which shows that CCD++ provides considerable speedups, showing its ability for simulating large and complex DEVS-based models. 1