Andreas Tolk

• PhD
• Chief Scientist Complex Systems Modeling at MITRE

Whether by design or by practice, systems engineering (SE) processes are used more and more often in Modeling and Simulation (M&S). While the two disciplines are very close, there are some differences that must be taken into account in order to successfully reuse practices from one community to another. In this paper, we introduce the M&S System De...

Big data allows users to cope with data that are huge in regards to volume, velocity, variety, and veracity. It provides methods and tools to extract aggregates and new information out of heterogeneously structured data or even completely un-structured data. Deep learning is a collection of algorithms that allows us to discover correlations and lea...

Modeling & Simulation (M&S) is making successful contributions to different areas in industry and academia. However, there are certain key issues that are preventing the field from addressing larger domains and from achieving wide-scale impact. Formulating these as grand challenges arguably focuses attention on these key issues and may bring a crit...

The enormous complexity of political decisions, especially with regard to crisis situations, requires innovative concepts for decision support. The focus here is always on people’s well-being. Artificial societies based on agent-based simulation models are a fairly new, forward-looking paradigm for this. Digital twins, on the contrary, are one of t...

This short feature article recommends learning from the M&S community and shifting from trust in the model towards trust in the result. Trust is not only gained by technically mature solutions but is predominantly shaped by the relationship between provider and customer.

Complex socio-technical systems have many challenging facets, comprising multiple, highly interconnected, and highly diverse technical and social components. Each entity represented by these components comes with many perspectives, methods, and tools developed in the supporting communities to address the subset of overall challenges the entity is c...

Introduction Advancements in information technology have facilitated information exchange practices within the Military Health System (MHS), enabling “systems of systems” approaches that broaden and coordinate the set of capabilities available to enhance patient outcomes. This is applicable for MHS modeling and simulation (M&S) applications as well...

Combat has seen fundamental changes over the past century—with new domains of warfighting (e.g., cyber, space); the introduction of nuclear and precision weapons; ubiquitous, all source intelligence; mixes of national, coalition, and private forces operating; and numerous other examples. Over this same period, combat simulations, and the attendant...

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 inf...

Increases in computational power have contributed to growing interest in using modeling and simulation (M&S) to better understand and address blast injury for US service members. The development of an M&S capability that can comprehensively simulate human injury, lethality, and impairment due to blast injury threats in the military environment requ...

p>The position paper summarizes the inputs of a set of experts from academia and industry presenting their view on chances and challenges of using ChatGPT within the Modelling and Simulation education. They also address the need to evaluate continuous education as well as education of faculty members to address scholastic challenges and opportuniti...

p>The position paper summarizes the inputs of a set of experts from academia and industry presenting their view on chances and challenges of using ChatGPT within the Modelling and Simulation education. They also address the need to evaluate continuous education as well as education of faculty members to address scholastic challenges and opportuniti...

Land-use planning for modern societies requires technical competence as well as social competence. We therefore propose an integrative solution enabling better land-use planning and management through better-informed decision-making. We adapt a method developed for cross-disciplinary team building to identify the stakeholders and their various obje...

Commissioned by the Society for Modeling and Simulation International (SCS), this needed, useful new ‘Body of Knowledge’ (BoK) collects and organizes the common understanding of a wide collection of professionals and professional associations. Modeling and simulation (M&S) is a ubiquitous discipline that lays the computational foundation for real...

We propose the use of artificial societies to support health care policymakers in understanding and forecasting the impact and adverse effects of policies. Artificial societies extend the agent-based modeling paradigm using social science research to allow integrating the human component. We simulate individuals as socially capable software agents...

Enhancing skills is one of the main reasons for the use of simulation. This chapter of the SCS M&S Body of Knowledge looks mainly at training. The use of simulators, often referred to as virtual simulation, is described and followed by the use of constructive simulation systems, where all relevant entities of interests are simulated. Examples from...

This chapter of the SCS M&S Body of Knowledge summarizes philosophical foundations that are only partially addressed in other chapters in a constrained manner. It starts with a philosophical discussion of simulation epistemology, including some idea about the role of ontologies as well. A timeline on scientific research and method development shows...

This chapter deals with models, data, and their relations and use. It introduces the big picture of the SCS M&S Body of Knowledge, providing taxonomies for models and their uses and resulting perceptions as well as an extensive section on data. It addresses the questions of modeling and various modeling formalisms, model engineering, and model cura...

Ethics is a branch of philosophy that studies moral problems. This chapter of the SCS M&S Body of Knowledge starts with a broader look at how ethics are influencing technical disciplines in general before looking at ethics for computer simulation in more detail. It devotes a section on ethics for simulationists and analysts, as they often provide g...

Climate change poses a risk for our health, national security, infrastructure, and economy, e.g., strains on infrastructure, changing migration patterns, and increased social and economic disparities. In seeking to mitigate the effects of climate change, policy makers must consider second and third order effects of policies in the context of affect...

Creating a more sustainable world will require a coordinated effort to address the rise of social, economic, and environmental concerns resulting from the continuous growth of cities. Supporting planners with tools to address them is pivotal, and sustainability is one of the main objectives. Modeling and simulation augmenting digital twins can play...

Within the modeling and simulation community, simulation-based optimization has often been successfully used to improve productivity and business processes. However, the increased importance of using simulation to better understand complex adaptive systems and address operations research questions characterized by deep uncertainty, such as the need...

Data analytics helps us better understand our current situation, including comprehending the effects of earlier decisions. Data identified to address the tasks at hand are collected, evaluated, and presented to decision makers. However, multi-criteria decisions and multi-objective decisions require increased trade-off options, particularly in compl...

Update: The first article at the bottom of the page: https://www.mdpi.com/journal/information/special_issues/Simulation_Modelling has been published. The first cfp was sent via: https://www.researchgate.net/publication/360161125_Open_Special_Issue_Simulation_Modeling_Theory_and_Practice_Pushing_the_Boundaries_Message_from_the_Guest_Editors There i...

Weapon systems of the 5th and higher generation are characterized by a significant increase in data utilized as well as multi-modality regarding receiving and transmitting these data. They utilize methods comparable to the Internet-of-Things or cloud-based technologies for cyber-physical systems. OMG's Data Distribution Services (DDS) were develope...

Abstract—Increasingly complex systems exist in dynamic environments where the system needs evolve in ways that are faster than it is possible to identify, much less comprehend, through human observation alone. To build such complex systems, system engineering teams should be augmented with real-time digital collaborators, not only in the design pro...

Based on the insights of experts in both domains, Simulation and Wargaming comprehensively explores the intersection between computer simulation and wargaming. This book shows how the practice of wargaming can be augmented and provide more detail-oriented insights using computer simulation, particularly as the complexity of military operations and...

Today's challenges must be addressed as socio-technical systems, including insights from the social sciences and humanities to adequately represent the human components. As results of simulations are increasingly driving and justifying political and social decisions, it is important to validate and verify (V&V) simulation and data. However, the und...

This call for papers is for a joint special issue of the Journal of Simulation and Health Systems - the journals of the Operational Research (OR) Society. We invite authors to submit original research on the use of cross-disciplinary approaches with computer simulation. The work must extend the theory, methodology, application and/or practice of mo...

Systems engineering practices are evolving to address fast-changing needs in fielding complex systems. These needs create an environment in which system needs evolve or change too quickly to be tracked or managed by humans’ natural capabilities. We propose that systems engineering must aid systems engineering managers by providing architectural alt...

Artificial Societies are extending the agent-based metaphor by using computational social science research allowing for human simulation. This poster provides an example how to apply it to evaluate the effects of health policy decisions on the opioid crisis in the Capital region.

Operating universities under pandemic conditions is a complex undertaking. The Artificial University (TAU) responds to this need. TAU is a configurable, open-source computer simulation of a university using a contact network based on publicly available information about university classes, residences, and activities. This study evaluates health out...

This final chapter provides a reflection on the case studies presented in the book, the use of the framework as an organizing taxonomy, and suggestions of future trends in this area. Overall, the research topics identified focus on the need to better integrate humans into the complex sociotechnical systems. Insights from the field of human systems...

The cloud computing paradigm allows ubiquitous access to resources and computational services. These shared assets can be accessed with limited administrative constraints, can rapidly be configured, and provide a huge shared pool of easily accessible information. Often, a significant portion of the computational services is provided by assets at th...

The COVID-19 Healthcare Coalition was established as a private sector-led response to the COVID-19 pandemic. Its purpose was to bring together healthcare organizations, technology firms, nonprofits, academia, and startups to preserve the healthcare delivery system and help protect U.S. populations by providing data-driven, real-time insights that i...

Modelling and simulation (M&S) techniques are frequently used in Operations Research (OR) to aid decision-making. With growing complexity of systems to be modelled, an increasing number of studies now apply multiple M&S techniques or hybrid simulation (HS) to represent the underlying system of interest. A parallel but related theme of research is e...

A Framework of Human Systems Engineering: Applications and Case Studies offers a guide to identifying and improving methods to integrate human concerns into the conceptualization and design of systems. With contributions from a panel of noted experts on the topic, the book presents a series of Human Systems Engineering (HSE) applications on a wide...

Complex system governance (CSG) is an emerging field, representing an approach to improve system performance through purposeful design, execution, and evolution of essential metasystem functions. The aim of this study was twofold: i) to understand how modelling and simulation (M&S) can be used to enhance the emerging field of CSG; ii) to evaluate d...

Complex System Governance (CSG) is an emerging field, representing an approach to improve system performance through purposeful design, execution, and evolution of essential meta-system functions. The aim of this study was twofold: (i) to understand how modeling and simulation (M&S) can be used to enhance the emerging field of CSG and (ii) to evalu...

Decision-making within a complex operating environment spanning multiple domains necessitates enterprise-level operational agility. In this case, operational agility involves ability to react to dynamic opponents and the orchestration of technical resources as well as alignment of managerial processes. A shift from the system level to the enterpris...

This book provides the state-of-the-art in methods and technologies that aim to elaborate on the modeling and simulation support to cyber physical systems (CPS) engineering across many sectors such as healthcare, smart grid, or smart home. It presents a compilation of simulation-based methods, technologies, and approaches that encourage the reader...

This chapter is summarizing the research ideas explicitly and implicitly discussed in the expert contributions to this book. It is meant to provide a repository of research ideas for academia and industry to meet the current and future requirements. The chapter elaborates on seven themes: common formalism, complex environments, complexity toolbox,...

Cyber Physical Systems (CPS) are hybrid systems comprising multiple components and many other combinations of various integrated but heterogeneous computational and physical capabilities. Todays embedded system such as iPhones and smart watches have integrated hardware and software solutions. There are engineering methodologies available to develop...

This book provides the state-of-the-art in methods and technologies that aim to elaborate on the modeling and simulation support to cyber physical systems (CPS) engineering across many sectors such as healthcare, smart grid, or smart home. It presents a compilation of simulation-based methods, technologies, and approaches that encourage the reader...

This epilogue to Human Simulation places the volume’s contributions into the context of the use of models in science, the potential of computational execution of concepts and ideas by using simulation, and the epistemological constraints of such efforts. It proposes that bringing social scientists, humanities scholars, and supporting simulationists...

This article evaluates the applicability of game theory within the government acquisition community to provide strategies that move potential vendors into a preferred negotiation point and expedite the decision-making process in acquisition. The research focuses on the application of utility models in support of a game theoretic foundation to provi...

Complex adaptive systems in nature may produce something new, like structures, patterns, or properties, that arise from the rules of self-organization. These novelties are emergent if they cannot be understood as any property of the components but are a new property of the system. Emergence is a key property of complex systems. A popular method to...

We are having seasons: summers and winters of many scientific disciplines. Many fields are experiencing hype cycles. Each one of us would remember “AI winter” from the history of Artificial Intelligence. Inflated expectations are followed by disappointment and eventually funding cuts. Renewing the interest takes then years if not decades. The Socie...

We are having seasons: summers and winters of many scientific disciplines. Many fields are experiencing hype cycles. Each one of us would remember “AI winter” from the history of Artificial Intelligence. Inflated expectations are followed by disappointment and eventually funding cuts. Renewing the interest takes then years if not decades. The Socie...

Using models to capture empirical insight and describe our current understandings has long been accepted as part of building scientific knowledge. Now, however, we use models for conducting simulation‐based experiments. Understanding the epistemological constraints of such models is important because models are merely purposeful abstractions and si...

Contributors offered suggestions to improve multi‐scale modeling that focused mainly on getting model substance right. This chapter is an edited but not iterated recounting of responses to questions that deal with simulation and emergence, how to relate models at different levels of resolution, and how to assure more humanness in agents. Contributo...

This uniquely inspirational and practical book explores human simulation, which is the application of computational modeling and simulation to research subjects in the humanities disciplines. It delves into the fascinating process of collaboration among experts who usually don’t have much to do with one another – computer engineers and humanities s...

This book is based on the “Summer Simulation Multi-Conference” (SCSC), which has been a prominent platform for the dissemination of scholarly research in the M&S community for the last 50 years. In keeping with the conference’s seasonal title, the authors have called this half-century “the summer of simulation,” and it has led not only to simulatio...

The social sciences and humanities are fragmented into specialized areas, each with their own parlance and procedures. This hinders information sharing and the growth of a coherent body of knowledge. Modeling and simulation can be the scientific lingua franca, or shared technical language, that can unite, integrate, and relate relevant parts of the...

The application of Complexity Science, an undertaking referred to here as Complex Systems Engineering, often presents challenges in the form of agent-based policy development for bottom-up complex adaptive system design and simulation. Determining the policies that agents must follow in order to participate in an emergent property or function that...

Natural complex adaptive systems are of particular scientific interest in many domains, as they may produce something new, like structures, patterns, or properties, that arise from the rules of self-organization. These novelties are emergent if they cannot be understood as any property of the components, but as a new property of the system. One of...

Recent developments of computational methods supporting scientific research have led to the rise of a variety of computational science disciplines, such as computational physics, computational biology, computational chemistry, computational social science, and many more. Although simulation is now widely regarded as the third pillar of science, wit...

This chapter introduces simple, complicated, and complex system definitions and shows how these system classes are related to simple, weak, strong, and spooky emergence, and which systems engineering methods can be applied to support the detection, understanding, and management of such emergence. It considers the purpose of systems engineering, as...

During the Spring Simulation Multi-Conference 2017, a group of invited experts discussed challenges in M&S of cyber physical systems. This 2018 panel is a follow-on activity, asking how the combination of various simulation paradigms, methods-so-called hybrid simulation-can be utilized regarding complexity, intelligence, and adaptability of cyber p...

This paper evaluates the state of the art of hybrid simulation support for cyber physical systems. The traditional definition for hybrid simulation is expanded to include recent research on multi-paradigm and other multi-faceted modeling approaches. Based on the review of current approaches, the focus of simulation support lies first in providing a...

Modeling and Simulation(M&S) has recently been applied to explore the nature of emergent behavior in complex systems engineering (CSE). M&S, along with Big Data technologies are at the forefront of such exploration and investigation. In the text: Emergent Behavior in Complex Systems Engineering: A Modeling and Simulation Approach, edited by Saurabh...

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In this chapter, we attempt to set the research agenda on emergence in the medium and long term. We first summarize the view of emergence from the authors in this book and conclude that almost all of them are focused on epistemological emergence, which results in better understand systems but fails in explaining the emergence of new categories as w...

A comprehensive text that reviews the methods and technologies that explore emergent behavior in complex systems engineering in multidisciplinary fields In Emergent Behavior in Complex Systems Engineering, the authors present the theoretical considerations and the tools required to enable the study of emergent behaviors in manmade systems. Informat...

Denis Noble’s book “The Music of Life – Biology beyond the Genome” helped introduce the idea for Systems Biology worldwide to biologists, including the medical simulation community. The traditional reductionist’s view is reducing the organism into progressively finer and finer components to understand the interactions on the lowest levels and recon...

The history of military simulation dates back to the earliest ages of conflict. Throughout the history, military personnel has employed cognitive devices to comprehend and plan for conflict. This chapter provides a history of military simulation, starting with a review of the board-based war games, progressing through the computerization of those w...

The Winter Simulation Conference celebrates its 50th anniversary in December 2017. Over these years, it became one of the leading simulation conferences worldwide, with more than 600 annual participants and thousands of publications shaping the international simulation research. This chapter describes the history of the conference, presents some hi...

It is often the case that models and simulations of subsystems such as the components making up a vehicle are created in isolation and must later be integrated with other models to create a model of the overall system. However, the reuse of existing models and simulations can be costly and time-consuming, and can yield uncertain results. Advances a...

Systemsengineering (SE) is understood as an interdisciplinary collaborative approach to derive, evolve, and verify a life cycle balanced system solution. Satisfying customer expectations has become more complicated and complex, as we are no longer designing systems optimized for a single point, but instead are focusing on systems which are sustaina...

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book provides an approach to understand what skills and knowledge make modeling and simulation (M&S) unique as a discipline, and what defines an M&S professional. It then presents information about the “Code of Ethics” for M&S professio...

This chapter introduces the reader to professional codes of conduct and ethics as they are used in building a strong ethically sound foundation for engineering professions. From a general introduction into the topic, followed by the discussion to what degree professional ethics can be coded, and under what constraints this can be done, the professi...

This chapter particularly focuses on the simulation systems engineering body of Knowledge (SSE BoK). It first presents the foundations and applications of SSE, and reveals an initial proposal for the knowledge areas of SSE. The SSE BoK is in this sense a part of the modeling and simulation (M&S) BoK. Tuncer Oren introduced his recommendations for d...

Chapters and Sections with Authors FOUNDATION 1. Introduction to the Facets of the Profession of Modeling and Simulation Andreas Tolk 2. An Index to the Body of Knowledge of Simulation Systems Engineering Umut Durak, Tuncer Őren, and Andreas Tolk 3. Code of Ethics Andreas Tolk EDUCATION 4. M&S as a Profession and an Academic Discipline: A Contemp...

The scientific community is aware of the experimenter’s regress: a research bias that occurs when the researcher unconsciously affects results, data, or participants in an experiment. Bias in simulation based experiments is no exception, but maybe even be the rule. The paper evaluates to what degree bias plays a role for the selection of simulation...

Simulation spielt eine entscheidende Rolle für die Realisierung intelligenter Roboter. Ein Roboter muss seine Umgebung wahrnehmen, eine sinnvolle Perzeption aus der zu dem vorhandenen Wissen und der neuen Information bilden, unter möglicher Berücksichtigung von Beiträgen weiterer Roboter oder Anwen-der zu einer Entscheidung kommen, und diese Entsch...

This broad-ranging text/reference presents a fascinating review of the state of the art of modeling and simulation, highlighting both the seminal work of preeminent authorities and exciting developments from promising young researchers in the field. Celebrating the 50th anniversary of the Winter Simulation Conference (WSC), the premier internationa...