SIMULATION: Transactions of The Society for Modeling and Simulation International

Barros, Fernando J

doi: 10.1177/00375497241238457pmid: N/A

This paper presents πHyFlow, a modular approach to the process interaction worldview (PI). Traditionally, PI supports a set of interacting processes without enabling modular and hierarchical model definition. πHyFlow basic models define a dynamic set of processes while also enabling a modular interface for supporting model composition. πHyFlow allows an exact representation of continuous signals based on the concepts of dense outputs, and generalized sampling. πHyFlow ability to support accurate models of hybrid systems is presented through a DC-DC converter (DCC) based on a resistor–capacitor (RC) electrical circuit. The DCC output voltage can be modeled by a first-order differential equation that is solved using an exponential time differencing (ETD) integrator. The DCC network model uses a digital on-off controller and an ETD. Simulation results are generated by πHyFlow++, a C++ implementation of the formalism.

Fard, Mostafa D; Sarjoughian, Hessam S

doi: 10.1177/00375497241233783pmid: N/A

Understanding the dynamics of complex systems requires developing and combining different kinds of models that can be simulated separately and together. Modeling the interactions as separate models contributes to building flexible hybrid simulation frameworks. In this research, a Discrete Event System Specification–based Interaction Model (DEVS-IM) framework is developed based on the Knowledge Interchange Broker (KIB) approach. This KIB-based RESTful modeling composition framework is shown to enable systematic modeling and simulation of interactions between disparate simulatable models. It supports storing IMs developed for componentized Water Evaluation and Planning System (WEAP) and Low Emissions Analysis Platform (LEAP) tools. It generates the skeleton of DEVS-IMs stored in database for DEVS-Suite simulator. An exemplar model consisting of water, energy, and IMs demonstrates this methodology for developing nexus models of water–energy systems.

Moreira, Rui A S; Marques, André P

doi: 10.1177/00375497241247039pmid: N/A

Passive damping treatments using viscoelastic materials (VEMs) are widely applied as addon solutions to control the dynamic response of light structures. These surface treatments are simple, reliable, and can be optimized by using proper design rules and simulation tools. In this work, a new treatment configuration is proposed, simulated, and assessed, being compared with the most effective configuration currently used. The novelty resides in the VEM layer’s geometry, which in the proposed configuration assumes a waved shape. This waved shape is imposed to the viscoelastic layer due to indentations created in the inner faces of the host structure and the constraining layer. The results demonstrate that the wavy configuration, designated as corrugated viscoelastic layer (CVL), outperforms the typical damping treatments for relatively thick host structures and when using thick VEM layers. In addition, this new configuration reduces the stiffness decoupling effect due to the soft VEM layer, restoring the flexural stiffness of the original undamped structure.

Negahban, Ashkan

doi: 10.1177/00375497241229757pmid: N/A

Besides its use as a powerful systems analysis tool, simulation has also been used for decades in educational settings as a teaching and learning method. Simulation can replace or augment real-world inquiry-based experiences by providing learners with a low-cost and risk-free experimentation platform to develop knowledge and skills in a simulated environment. This paper presents an overview of current applications and the ongoing transition from physical experimentation to digital simulations and immersive simulated learning environments in engineering education. The paper highlights major implementation and research gaps related to simulation-based learning and immersive simulated learning environments, namely, lack of integration with learning theories and limited formal assessments of effectiveness. Potential implementation approaches and important areas for future educational research are discussed and exemplified in response to the identified gaps. The discussions presented are intended for simulationists, educational researchers, and instructors who are interested in designing and/or utilizing engineering education interventions involving simulated learning environments and immersive technologies in their teaching and educational research. In particular, the Immersive Simulation-Based Learning (ISBL) approach discussed in the paper provides a framework for simulationists to reuse the models developed as part of their simulation projects for educational purposes.

Tolk, Andreas

doi: 10.1177/00375497231216471pmid: N/A

This position paper provides first, a literature survey of selected domains with significant contributions to simulation interoperability research, such as defense and healthcare simulation, including insights from academia and research organizations. Next, four main interoperability methods are reviewed, i.e., messages-oriented methods, use of information exchange models and common object models, and reference modeling, including ontological means. This review leads to the observation that successful approaches do not only rely on technical solutions but are also using conceptual alignment of the underlying models as well. The Levels of Conceptual Interoperability Model is revisited to consider how it contributed—and still contributes today—to reach meaningful interoperability between model-based solutions. Its descriptive and prescriptive use is discussed, and it is applied to the four methods to show its practical applicability.

Frydenlund, Erika; Martínez, Joseph; Padilla, Jose J; Palacio, Katherine; Shuttleworth, David

doi: 10.1177/00375497241239360pmid: N/A

We examine the potential of prompting a large language model-based chatbot, ChatGPT, to generate functional simulation model code from a prose-based narrative. The simple narrative describes how the mode of transportation for elementary school students changed due to the COVID-19 pandemic and related factors, including a lack of available bus drivers, lack of mask enforcement on buses, and inclement weather. We document the process of providing this narrative to ChatGPT and further prompting the chatbot to generate model code to represent the narrative and to make it executable. We test ChatGPT’s ability to use prose descriptions of a phenomenon to generate simulation models using three paradigms: discrete event system, system dynamics, and agent-based modeling. Our findings reveal that ChatGPT could not produce concise or executable models, facing higher difficulty when asked to do so in programming languages it was less familiar with. This analysis underscores the strengths and limitations of the current state of this technology for modeling and simulation. Furthermore, we propose how future advancements in Large Language Models may aid the simulation modeling process, increasing transparency and participation in multidisciplinary team efforts.

Ali, Zeeshan; Biglari, Raheleh; Denil, Joachim; Mertens, Joost; Poursoltan, Milad; Traoré, Mamadou Kaba

doi: 10.1177/00375497241234680pmid: N/A

As digitalization is permeating all sectors of society toward the concept of “smart everything,” and virtual technologies and data are gaining a dominant place in the engineering and control of intelligent systems, the Digital Twin (DT) concept has surfaced as one of the top technologies to adopt. This paper discusses the DT concept from the viewpoint of Modeling and Simulation (M&S) experts. It both provides literature review elements and adopts a commentary-driven approach. We first examine the DT from a historical perspective, tracing the historical development of M&S from its roots in computational experiments to its applications in various fields and the birth of DT-related and allied concepts. We then approach DTs as an evolution of M&S, acknowledging the overlap in these different concepts. We also look at the M&S workflow and its evolution toward a DT workflow from a software engineering perspective, highlighting significant changes. Finally, we look at new challenges and requirements DTs entail, potentially leading to a revolutionary shift in M&S practices. In this way, we hope to foster the discussion on DTs and provide the M&S expert with innovative perspectives.