International Journal of System of Systems Engineering (12 papers in press)
A satisfactory multi-agent single-machine considering a cross-docking terminal
by Mohammadbagher Afshar-Bakeshloo, Fariborz Jolai, Mostafa Mazinani, Reza Tavakkoli-Moghaddam
Abstract: This study addresses a two-agent single-machine scheduling problem; whose objectives are to maximize the agents service levels regarding their desired time windows. Indeed, this is a new variant of multi-agent scheduling problems that agents time windows are taken into account. Proposing a useful dashboard to determine optimal sequences of the jobs is essential since all the jobs (i.e., agents demands) are characterized by unequal release dates, due dates, and deadlines. Employing this dashboard, the decision maker tries to provide a schedule based on a specific level of services for each agent. A cross-dock terminal with multi-inbound door and one-outbound door is an excellent example of the proposed model. Here, the decision maker (i.e., dispatcher) schedules the jobs so that each agent gets a pre-determined level of satisfaction. This problem is formulated with a mixed-integer linear programming model considering a piecewise linear function. The results show that the optimally non-dominated solutions can be obtained by the CPLEX whenever n<20. In contrast, for n>20, exploitation of the heuristics becomes essential. The results show that the multi-objective imperialist competitive algorithm (MOICA) performs better than the non-dominated sorting genetic algorithm (NSGA-II) and multi-objective invasive weed optimization (MOIWO). Furthermore, substitution of the service level for tardiness is demonstrated to be a more reasonable measure for customer satisfaction, precisely when the agents announce their desired time windows.
Keywords: Multi-agent single-machine scheduling; Tardiness; Time window; Customer satisfaction; MOICA; Cross-dock terminal.
SERIOUS GAMING: IMPLICATIONS FOR RESILIENCE GOVERNANCE OF CRITICAL INFRASTRUCTURE
by Shelley Jules-Plag, Jarutpong Vasuthanasub, Adrian Gheorghe
Abstract: Risk and risk governance of critical infrastructure has been well studied. Resilience governance however is still in the process of identifying suitable approaches. Assessments of resilience are often based on value perspectives and impacted by social constructs, making it difficult to fit a singular approach to resilience governance, creating a wicked problems for decision makers. The paper looks at the steps utilized in Risk Informed Decision Making (RIDM) and their applicability to Resilience Informed Decision Making (ReIDM), identifying benefits and limitations. It proposes a framework to address the process-oriented approach needed for ReIDM. To demonstrate the framework we utilize a number of risk assessment methodologies, and a simple time-dependent game play simulation SimCityTM model to explore the manifestation of infrastructure development strategies over time, illustrating the importance of tools that facilitate insight into the domino effects of alternative approaches and mitigation strategies to resilience governance.
Keywords: Serious Gaming; Simulation Computer Game; SimCity Application; Risks and Vulnerability; Critical Infrastructures Resilience; Resilience Governance; Resilient Informed Decision Making Process.
A Complex Structure Representation of the US Critical Infrastructure Protection Program based on the Zachman Framework
by Unal Tatar, Bilge Karabacak, Polinpapilinho Katina, Andy Igonor
Abstract: Critical infrastructures are vital assets for public safety, economic welfare or national security of countries. The importance of critical infrastructures necessitates state-level coordination of security efforts based on some rigid policies, strategies, and procedures. This hierarchical set of rules is collectively referred to as the Critical Infrastructure Protection Program (CIPP). As the pioneer of CIPP, the United States (US) has a very complex program in which partners and stakeholders have multiple and varied interacting roles and responsibilities. The complexity of roles and interactions creates a need to make a representation of these complex structures by using intuitive tools. The Zachman Framework is such a tool that provides a formal and structured way of viewing and defining a complex enterprise. It is represented by a 6x6 matrix with rows defining stakeholders and columns defining underlying interrogatives. In this article, a proof-of-concept study is performed to represent the US CIPP using the Zachman Framework. The proof-of-concept study showed that the Zachman Framework could be beneficial in overcoming challenges of a CIPP program which can be regarded as a complex enterprise.
Keywords: Critical Infrastructure Protection Program; Cyber Security; Roles and Responsibilities; Stakeholders; Enterprise Architecture; Zachman Framework; System of Systems.
The System of Systems paradigm to reduce the complexity of data lifecycle management. Case of the Security Information and Event Management
by Mohammed EL ARASS, Nissrine SOUISSI, Khadija OUAZZANI TOUHAMI
Abstract: Big Data management is becoming a challenging mission. Several data lifecycles were proposed to deal with this situation, but neglect cycle management and big data requirements. To fill the gap, the paper introduces the System of Systems paradigm to reduce the complexity of cycle management and thereby satisfy Big and Smart Data requirements. This paper demonstrates that the SoS paradigm applied to data lifecycle makes it possible to better organize data at the managerial and operational levels. This demonstration has been proven through a SIEM POC (Security Information Event Management Proof Of Concept) use case.
Keywords: Big Data; Complex System; Cybersecurity; Data LifeCycle; DLC; Smart Data; Smart DLC; SysML; Requirement; SIEM; Security Information Event Management; SoS; System Of Systems; SoSE; System Of Systems Engineering.
Vitasystems Theory for Aircraft Industry Development
by Abrek I. Ayupov, Gennadiy M. Alakoz, Sergey I. Plyaskota, Elizaveta N. Bydanova
Abstract: The current state of vitasystems theory and the application of a vitasystem approach to the problems of the development of large-scale aerospace complexes, including aircraft industry, are considered. The origin of the concept and theory of vitasystems is connected with the task of restoring the Russian aircraft building industry, the degradation of which occurred in the post reorganization period. At the beginning of the century, in 2001-2006, commissioned by the Russian Industry and Energy Ministry, a number of research projects to find rational ways to organize aircraft industry in new public and technological conditions were performed
Keywords: vitasystem; vitasystems theory; vitasystem approach; organisation of aircraft industry in new public and technological conditions; Russia.
Stability analysis in cooperative distributed model predictive control
by Wang Jianhong
Abstract: Due to cooperative distributed model predictive control scheme is widely applied in large scale networks of systems, so asymptotic stability is a very important index for measuring the performance of cooperative distributed model predictive control. Based on the obvious inequality from classical Lyapunov stability condition, we derive a set of linear matrix inequalities to replace the common inequalities by using Schur complement and S-procedure. Furthermore when combining local state and input constraint sets, a set of more complex linear matrix inequalities is used to guarantee the asymptotically stable for cooperative distributed model predictive control.
Keywords: Cooperative distributed; Model predictive control; Stability; Linear matrix inequality.
On extending transitions logic in Hybrid Dynamic Systems based Bond Graph and Petri Nets combination
by Bouhalouane Mokhtar, Sekhri Larbi, Haffaf Hafid
Abstract: The increasingly important interaction between phenomena of a continuous nature and discrete nature makes hybrid dynamic systems (HDS) more complex. The continuous behavior is due to the natural evolution of the physical process while discrete behavior can be due to the presence of switches. in order to better take into account complexity of the resulting heterogeneous dynamics; We propose an unified and integrated fuzzy logic hybrid approach extending the concept of a classical switch from "On / Off" bond graph type modeling to a logical transition that takes into account a gradation instead of abrupt behavioral changes. We deal with ideal model complexity of bond graph and Petri net combination due to ideal switching concept. This approach stems from artificial intelligence subfield and allows extension of the reachable states space where we propose real physical intermediate states (fluidification) that can be maintained with a sense. We also modify the mathematical structure of ideal primitive switching element (PSTS) by proposing a formula based on predictive and effective notions that fully comply with standard bond graph syntax and semantics as well as the Petri Nets, grants a freedom of the sampling instants according to the solver. We demonstrate the effectiveness of our approach on a flow control Bi-tank and its usefulness both in academia and industrial field. Finally, we discuss some ideas about discrepancy between the level of mathematical abstraction and that of the physical level.
Keywords: SDH; STS; PSTS; DAE; TPN; Bond Graph; Petri nets.
Mission Planning and Scheduling for Earth Observation Space System
by Amr Qamar, Essam Eldin Salah, Khaled Badran, Gamal ElNashar
Abstract: The mission of an Earth Observing Satellite is to image parts on the earth surface trying to satisfy the received requests according to a certain optimization criterion. A Mission Planning and Scheduling system (MPS) is used to manage this mission which is a combinatorial optimization NP-hard problem. In this paper, the problem is modeled and solved as a Constraint Satisfaction Problem using the Constraint Programming Technique. Our target is the heterogeneous constellation that consists of agile satellites with different specifications, different orbits' types and/or different payload types. Six objectives are implemented in the proposed system, three of them are not used before. In all the objectives, the number of images included in the plan is to be maximized. Four search algorithms are used in solving the problem in addition to using a two phase algorithm consists of hill climbing and tabu search noted here by hill climbing tabu search algorithm. The system is dealing with different planning horizons. It was tested for up to (3) satellites, (2500) targets, and (1) month planning horizon. For this complicated case, using any one of the objectives with any of the five search algorithms, the CPU time was less than (1000) seconds and the Normalized Score was greater than (99). This means that the proposed system behaves in a good manner giving good comparative results even if the case study is so complicated.
Keywords: Earth observing satellites; planning and scheduling; mission management; constraint satisfaction problem; heterogeneous
constellation; agile satellites.
Developing a Systematic Methodology to Build a Systems Dynamics Model for Assessment of Non-technical Risks in Power Plants
by Sahar AL Mashaqbeh
Abstract: In a dynamic business environment like the energy sector, power plants face several complex risks, including both technical and non-technical risks. These risks are not isolated, as their impact may affect a series of interrelated risks. To add to this complexity, the assessment of those risks may change with time in a dynamic business environment. This situation makes the strategic decision-making process less effective regarding the successful design of a risk management system. Understanding the dynamic behaviour of a complex system of interrelated risks in the energy sector is very important to achieve a more sustainable overall performance of the power plants. Thus, it is important to further develop systematic risk assessment methodology that could help to identify and analyse those interdependencies among risks and to understand the dynamics of these in complex systems, as it is the case of power plants. This paper aims to develop a System Dynamics (SD) methodology to support the development of risk assessment models for power plants. In addition, improve the policymakers understanding regarding risks and the related decision-making process. This paper will focus on one risk perspective which is the environmental dimension and just the causal loop diagram is created. Thus, the first step to develop a SD model will be applied while the final developed SD will be discussed in the future where the paper focuses only on developing a systematic methodology to develop a SD model.
Keywords: System dynamics; Risk assessment; non-technical risks; Causal Loop Digrams; Stock and Flow Diagram.
Special Issue on: Soft Operations Research Methods for Complex Systems
Using rich pictures outside of soft systems methodology: a case study analysis
by Tessa Berg, Simon Bell, Steve Morse
Abstract: The aim of this paper is twofold. Firstly we will highlight how a problem structuring tool, namely the Rich Picture, is being used across many disciplines outside of the soft system methodology which has historically been its home. Secondly, we highlight the controversial presence of non-conforming Rich Picture research and an apparent reluctance to publish from the systems community. In this paper we provide examples of rich picture research used independent from methodology and focus on one case study that uses a novel method of content analysis to appreciate the significance of the stories within their pictures. We demonstrate the theoretical justification and efficacy of an innovation in the assessment of the Rich Picture and its use as a tool to discern issues of importance across mixed groups. We discuss the responses to this work and the implications for innovation within soft OR research. We propose that the Rich Picture should not be seen as sacrosanct just because it derives from a well-established and much respected methodology. We argue that the Rich Picture can be a flexible space where any practitioner can negotiate shared understanding without methodological constraint.
Keywords: rich picture; soft systems methodology; SSM; innovation; problem structuring.
Categorizing and clustering knowledge in Fuzzy Cognitive Maps
by Alexander Metzger, Steven Gray, Ellen Douglas, Paul Kirshen, Nardia Haigh
Abstract: The literature on managing environmental hazards in complex human-natural systems increasingly acknowledges the importance of integrating diverse stakeholder mental models into decision-making. Participatory Fuzzy Cognitive Mapping (FCM) provides an effective tool in this process, as it allows representation of mental models as complex causal networks that aid in the study of knowledge and understandings. While most participatory FCM research has studied mental model variation using graph theory and other structural metrics, our goal is to demonstrate a generalizable approach for analyzing perspectives and content. We use a novel method of knowledge categorization to identify variation among stakeholder mental models and explore its implications for social learning and collaboration. In our case study of flood managers in Boston, Massachusetts, our findings include identification of knowledge gaps, differing priorities among individuals and across jurisdictional scales and opportunities for learning and collaboration.
Keywords: soft systems; fuzzy cognitive mapping; mental models; social-ecological systems; participatory modeling; environmental hazards; flooding; adaptive management; social learning; collaboration; knowledge clustering; knowledge categorization.
Systemic Analysis of a Drug Trafficking Mess
by Nick Sapiano, Patrick Hester
Abstract: The United States, in an effort to combat drug trafficking at the federal level, faces an unenviable task. Trying to address this situation involves considerations of drug production, importation, and consumption. The Think-Act-Observe (TAO) approach (Hester & Adams, 2017) provides a multi-methodology for systemically addressing these, and other, complex, interconnected problems. The three stages (Think, Act, Observe) draw on a theoretical foundation of systemic thinking and provide a practical, iterative approach for increasing understanding of the mess under consideration, executing an intervention framework, and analyzing that implementation. This paper presents a practical demonstration of the TAO approach by describing the application of the Think stage and its six constituent perspectives as they pertain to international drug trafficking. After an articulation of the constituent problems of the mess (drug production, importation, and consumption) and their collective stakeholders, the problems are individually subjected to systemic analysis through the perspectives of who, what, why, where, how, and when to build an expanding Fuzzy Cognitive Map; further, the production problem analysis is reported in detail as a case study. These problem-level analyses are then integrated to form a meta-perspective of the drug trafficking mess, which is then utilized in the Act stage to analyze the systemic impact of simulated potential interventions. Recommendations for future action are provided in support of the Observation stage. Armed with these recommendations, problems owners can move forward in an effort to resolve all identified problems in a manner satisfactory to all affected parties.
Keywords: Systemic thinking; systems analysis; drug trafficking; systems theory; wicked problems; mess.