International Journal of System of Systems Engineering (12 papers in press)
Investigation of design and coordination issues in outpatient chemotherapy clinics using an ontology-based conceptual model
by Mahmoud Heshmat
Abstract: Chemotherapy is one of the most common treatment options for cancer. However, the caring service design is complex. In this paper, we develop an ontological model to check the consistency in the design process for identifying potential conflicts and improving communication and coordination in Outpatient Chemotherapy Clinics (OCCs). Checking the design issues is based on the notion that ontology could be used to conceptualise and represent the coordination and communication barriers in the current design. The paper describes how potential inconsistency might be detected through a conceptual model to account for the context of OCCs using the enterprise engineering approach DEMO (Design and Engineering Methodology for Organisations), and re-engineering or modification of the inconsistencies can be accomplished. The implications of the developed model revealed guidelines for modelling an ontological representation and automatically identifying problems and conflicts in the design process of the corresponding system. The main contribution of this work is exploring and proposing a solution for the explored coordination and communication issues between actor roles, in particular between the patient appointments scheduling stage and the treatment planning stage. This observed hindrance reflects two decision makers with opposing objectives for the same patient, namely the oncologist and the appointment scheduler in the actual system. Our improving suggestion is to provide an information link between the treatment planner and the patient appointment scheduling transaction by which the two actors supply each other with information converging to one statement. This result could be input to a prospective coordination and communication platform.
Keywords: Enterprise Ontology; Outpatient Chemotherapy Clinics; DEMO.
A Decision Making Support System for Identification, Management and Assessment of Territorial Vulnerability
by Roger Enrique Guzmán Avendaño, Holman Bolívar, Raul Menendez, Edwin Duran
Abstract: This paper presents the model used to support a decision making tool for guiding
interventions in a territory. After conducting a systematic review to identify multi-criterion decision models relevant to the case on hand, a system based on service-oriented architecture was implemented The developed application allowed to obtain the short-, medium- and longterm actions necessary to strengthen a region before a natural disaster. As input to the tool, we used the information that characterizes a territory, starting from indicators grouped by dimensions (environmental, urban-regional, political-institutional, economic-productive and sociocultural). The information processing generates an overall vulnerability index and, for each dimension, the system recommends the actions to take. Even though the decision making models based on multi-criteria analysis produced different results, their combination with a services oriented architecture was seen as the best strategy for developing the decision making support system.
Keywords: Information System; Multicriteria Decision; Systems for Decision Making,
Modeling and Simulation of System-of-Systems (SoS) using P-systems theory
by Shreyas Subramanian
Abstract: This paper connects two independent fields of research - System-of-Systems (SoS) and P-systems. P-systems, originally inspired by basic features of biological membranes, where objects are placed into compartments defined by a membrane structure, and evolve according to reaction rules. Systems that belong to a particular level in the hierarchy of a SoS are can be understood to be within a membrane of certain depth. Also, objects in P-systems evolve in a maximally parallel, non-deterministic manner, a preferred method of evolution for many intractable SoS problems. Transitions of individual systems to other systems, or to alternative configurations can be easily realized using the format of P-systems. By casting typical SoS problems into P-system representations, we demonstrate the ease of problem set up, and the possibility of solving commonly intractable SoS modeling and simulation problems in feasible time. An example problem involving communication between aircraft is studied to illustrate the applicability of P-systems theory to SoS.
Keywords: Modeling; System-of-Systems (SoS); P-Systems; membrane computing; evolving.
Leadership and Foresight in Complex System Governance
by Dave Walters
Abstract: Complex System Governance (CSG) is an emerging field focused on addressing complex systems and related problems. CSG is related to System of Systems Engineering (SoSE) in that both are concerned with integration of multiple complex systems with the desired outcome of capabilities beyond those available by the individual systems. Specifically, CSG focuses on the design, evolution, and execution of (metasystem) functions essential for system operations and survival (viability). Included are functions for monitoring the systems environment and developing reactions to changes encountered therein. Foresight is a process to expand awareness and clarify emerging conditions. The purpose of this paper is to explore the influence foresight might have on the functions performed by the CSG environment monitoring and metasystem development/evolution subsystems, and the role of leadership in designing and enabling the means for those functions to be performed.
Keywords: System of Systems; Complex systems; foresight; leadership; complex system governance.
Application of bounded error identification into model predictive control
by Wang Jianhong
Abstract: In this paper, we apply bounded error identification into model predictive control (MPC). After introducing the family of models and some basic assumptions, we present bounded error identification to construct the interval predictor, using the neighborhood of a given data point. To guarantee the obtained interval predictor to be a minimum interval predictor, two optimal vectors used to adjust the width of the obtained interval predictor are suggested to be piecewise affine forms, using the Karush-Kuhn-Tucker (KKT) optimality conditions. When to apply interval predictor into model predictive control, the midpoint of that interval is chosen in an optimization problem to obtain the optimal control input for model predictive control. The property that control input only exists in its own cost function inspires us to use parallel distributed algorithms to solve unconstrained or constrained optimization problem, and the detailed computational process on Newton algorithm and Augmented Lagrangian algorithm are given for the sake of completeness. Finally the simulation example results confirm our theoretical results.
Keywords: bounded error identification; model predictive control; prediction; parallel distributed algorithm.
Systemic Intervention Methods Supporting Complex Systems Governance Initiatives
by James C. Pyne, Charles B. Keating, Polinpapilinho F. Katina, Joseph M. Bradley
Abstract: Complex System Governance (CSG) is an emerging field with potential to enhance capabilities for design, execution, and evolution of complex systems. CSG offers a theoretically grounded, model informed, and methodologically driven approach to more effectively deal with complex systems and their problems. However, initial CSG applications have identified multiple impediments to systemic intervention to deploy this new and novel field. In this paper we discuss a strategy to effectively deploy systemic intervention in support of CSG. Four primary objectives are pursued, including: (1) identification of three major forms of systemic intervention for complex systems in general (2) presentation of a dynamic and tailored approach (CSG-Entry) to improve prospects for introductory systemic intervention for CSG, (3) results from an initial application of CSG-Entry in a field setting, and (4) suggestion of lessons learned from initial applications of CSG-Entry in relationship to systemic intervention. (5) Two more methods that can be combined with CSG-Entry to generate sufficient information for planning a comprehensive systemic intervention. The paper concludes with examination of future development directions for systemic intervention to advance CSG performance.
Keywords: Complex Systems Governance; Enterprise System Governance Systemic Intervention; System Development.
Special Issue on: Critical Success Factors for Public Transportation
Wheel Maintenance in Rolling Stock: Safety Challenges in the Defect Detection Process
by Maria Mikela Chatzimichailidou, Alberto Martinetti, Arnab Majumdar, Leo A.M. Van Dongen, WASHINGTON Y. OCHIENG
Abstract: The proper and timely maintenance of railway rolling stock is essential for the safety of railway operations. Inaccurate inspection can lead to inadequate repair of defects and to great safety challenges in respect to the entire railway system. The detection and repair of any defect, such as cracks, in the wheels prior to a failure can significantly reduce train derailments and improved operational performance. This paper examines the wheel maintenance process in maintenance depots in the Netherlands on the basis of literature review, observations and interviews. First, it highlights various detection methods, including the risks of the incorrect detection of a flawed wheel profile. This paper introduces a flowchart as a concise illustration of the maintenance process; that is, both the detection and treatment of defects. With this in hand, the authors, as well as anyone involved in maintenance, are able to identify the points where the process is vulnerable and may be prone to incidents/accidents. Based on this procedure, improvements to the current wheel maintenance process can be proposed. The method that the flowchart is based on is also presented herein, along with the findings obtained throughout its steps.
Keywords: Maintenance; Safety; Wheel Defect; Rolling Stock.
The Redesign Process of the Timetable for the Dutch Railway Sector: a Theoretical Approach
by Femke Bekius, Sebastiaan Meijer
Abstract: The design of a new timetable for a railway system is a complex process, especially when the design starts from scratch. In this case the process is fundamentally different and much more complex than the yearly design process. Focussing only on the product, i.e., the timetable, and the exchange of information from one design phase to the next, does not cover the complexity and dynamics of the design process. Strategic actor behaviour and contextual factors are underexposed by other papers on theory of designing civil infrastructures, such as timetable design for railway systems. Therefore, we investigate the redesign process of the timetable for the Dutch railway sector from two perspectives: (i) an engineering perspective, and (ii) an actor and context perspective. To indicate the successes and failures of the redesign process of the timetable the design process is characterised using a framework that includes these two perspectives: the PSI framework. Several design phases are distinguished and at the transitions between the design phases misalignments are identified. The theoretically found misalignments are compared with empirical data to conclude on a set of improvements for design processes in the Dutch railway sector. Areas perceived as particularly problematic are knowledge transfer between the first design phases, decomposition of one design phase into several separate products, and composition of multiple products into one final design with corresponding actors and institutions.
Keywords: design theory; design process; Dutch railway sector; railways; PSI framework; case study; complexity; Complex Adaptive Systems; Systems of Systems.
Validity of Railway Microscopic Simulations Under the Microscope: Two Case Studies
by Bill Roungas, Sebastiaan Meijer, Alexander Verbraeck
Abstract: Simulations are the core of every railway system. Changes in the timetable and the infrastructure, or even in the internal processes of a railway company should be, and usually are, first tested through simulations. Given their significance and potential impact, simulations should be primarily validated; validation ensures - at least to some extent - that the returned results are credible and can be used for the intended purpose. This study is a detailed report on two case studies from the railway sector. The aim of this paper is to identify critical factors that can advance or hinder the validity and the effective usage of simulation models.
Keywords: simulations; validation; railways; case study.
There is no spoon: applying virtual reality for maintenance training of rolling stock technicians
by Alberto Martinetti, Koen 't Hart, Roy Damgrave, Leo Van Dongen, Robin Turkenburg, Andre Nouwens
Abstract: Introducing into operations new rolling stocks requires re-educating technicians and operators for being able to properly work on new and different assets. The training sessions are often performed under substantial time constraints and with a lack of resources. Re-training the technicians is a cost intensive process as it is for training new employees. The aim of the paper is to test and evaluate a Virtual Reality (VR) training solutions to decrease costs and to increase technicians availability, safety during maintenance operations and education performance with the support of Netherlands Railways (Nederlandse Spoorwegen NS). Firstly, the study explores the possible maintenance tasks analysing the benefits for VR implementations; secondly, it evaluates the attitude of technicians trained with the proposed VR approach. Finally, it discusses the results and provides general applicable suggestions for the use of VR in other training activities.
Keywords: Maintenance; Virtual Reality; Rolling Stocks; Training.
Framing Success: the Netherlands Railways Experience
by Mohammad Rajabali Nejad
Abstract: Here we introduce the success framework, an integral view on the critical success factors to accommodate flexibilities required for tacking with the dynamism of rail industry both technically and organizationally. The success framework adapts two basic strategies that contribute to success. First, a clear set of objectives across the stakeholders. Second, cooperation and co-creation of values for achieving the objectives. We propose an integral approach for identification and accomplishment of the critical success factors. The application of the framework is further explained through a case study.
Keywords: success; factors; success framework; railways; Netherlands.
DEMATEL-AHP technique to minimize departure delays due to airspace congestion: A case in Mactan-Cebu International Airport
by Rosein Jr. Ancheta, Miriam Bongo, Lanndon Ocampo, Dennis Anthony Kilongkilong, Miraflor Amit, Odiza Cuizon, Nikki Joy Arda
Abstract: Airspace congestion has a direct effect on departure schedules of aircraft. In events when there is a constrained airspace due to various factors such as adverse weather, departure delays may be potentially serious. Due to the complexity of the problem of choosing the best possible option in addressing airspace congestion, a combined multiple criteria decision making (MCDM) approach is used for the decision-making process. Furthermore, this paper incorporates the views of experts representing air traffic service and airlines management which is significant in choosing a viable solution to both stakeholders operating air transport. It has been found that both air traffic service and airlines management give most priority to safety, thus, prefer to apply for ground delay program during airspace congestion.
Keywords: departure delays; airspace congestion; analytic hierarchy process (AHP); decision making trial and evaluation laboratory (DEMATEL); multiple criteria decision making (MCDM).