Towards affordably adaptable and effective systems

2014 IEEE International Conference on Systems, Man, and Cybernetics (SMC)

2014

Self Cite

Contract-based design (CBD) employs formalisms that explicitly define system requirements, constraints, and interfaces. This paper explores a contract-based design paradigm for expressing system resiliency features. Specifically, resilience formalisms are defined in terms of invariant and flexible assertions. A flexible assertion is one that is learned during system operation and can accommodate unpredicted system behaviors. Invariant assertions are fixed system constraints that are known a priori. A general model structure comprising four key features that contribute to system resilience is presented. In particular, the concept of flexible contracts is operationalized using the Hidden Markov Model (HMM) construct. A system architecture based on flexible contracts and lightweight error monitoring and resiliency response mechanisms is also presented. The proposed framework can serve as a testbed to experiment with different systems resiliency approaches.

Section: Discussionmentioning

confidence: 99%

A flexible contracts approach to system resiliency

Sievers

2014 IEEE International Conference on Systems, Man, and Cybernetics (SMC)

2014

Self Cite

“…Since change tends to become increasingly more costly with greater levels of integration, it is imperative to develop an understanding of how the system is likely to respond to future change, and where possible, create a resilient design, i.e., a design that can accommodate or adapt to change [9], [10]. Eckert, Clarkson, and Zanker [11] discovered that when change is introduced into one or more components within a highly connected system, the ripple effect of the change can propagate upstream (e.g., to reset previous assumptions) and downstream throughout the system.…”

Section: Model-driven Storytelling Methodologymentioning

confidence: 99%

Exploring and assessing complex systems' behavior through model-driven storytelling

Spraragen

2014 IEEE International Conference on Systems, Man, and Cybernetics (SMC)

2014

Self Cite

Complex systems are difficult to analyze because of unknown interactions and dependencies among system components, and between the system and the environment. These interactions and dependencies tend to produce unpredictable behaviors that can often lead to detrimental outcomes. Traditional systems engineering that relies on reductive approaches are not suitable for the analysis and design of complex systems. This recognition has led to the development of new paradigms, methods, and tools that better enable: exploration of a complex system's behavior and tradespace; detection, diagnosis, and visualization of component/subsystem dependencies and interactions; and identification, alerting, and circumvention of potentially undesirable interactions. This paper presents a system model-driven interactive storytelling approach for analyzing interactions and dependencies within complex systems, and between complex systems and the environment. An exemplar complex system is used to convey key elements of the approach. The methodology is applicable for a variety of complex systems such as global supply chains, power and energy management, transportation networks, aerospace and aviation enterprises, and defense systems.

“…Parnell provides a thorough treatment of the MODA process (Parnell et al, 2013) while Neches and Madni write about the opportunity to use MODA for enhanced upfront engineering (Neches & Madni, 2013) and Buede specifically addresses the use of MODA to inform early requirements (Buede, 1997b;Buede, 1994;Buede, 1997a). Foundational works such as (Keeney, 1982;von Winterfeldt, 1980;Howard, 1988;Keeney & Raiffa, 1976;Raiffa, 1968;Kirkwood, 1992;Howard & Matheson, 2005;Howard et al, 1968;Hammond et al, 1998;Bond et al, 2010;Keeney, 2012;Raiffa, 1969;Keeney & von Winterfeldt, 2007;Keeney & Gregory, 2005;Kirkwood, 1996;Keeney, 2002;Keeney, 2009;Keeney, 1974) (Shachter & Kenley, 1989) and work on cost/schedule models ) also have potentially strong ties to MODA design alternative selection methods.…”

Section: An Approach To Design Alternative That Meets Required Princimentioning

confidence: 99%

Measuring Perceived Risk of Pitfalls Associated with Systems Engineering Tradeoff Analyses

Cilli¹,

Parnell²,

Cloutier³

et al. 2017

EMR

The U.S. Department of Defense (DoD) has recently revised the defense acquisition system to address suspected root causes of unwanted acquisition outcomes. One of the major changes in the revised acquisition system is an increased emphasis on systems engineering trade-offs made between capability requirements and lifecycle costs early in the acquisition process (Cilli, Parnell, Cloutier, & Zigh, 2015). Given that systems engineering trade-off analyses will play a pivotal role in future defense acquisition efforts, this paper takes an in-depth look at the state of systems engineering trade-off analysis capability through a review of relevant literature and a survey of systems engineering professionals and military operations research professionals involved in defense acquisition. The survey was developed to measure the perceived level of difficulty associated with compliance to the revised defense acquisition system mandate for early systems engineering trade-off analyses and to measure perceived likelihood and impact of potential pitfalls within systems engineering trade-off studies. The survey instrument was designed using Survey Monkey and was deployed through a link posted on several groups within LinkedIn, a professional social media site, and was also sent directly via email to those with known experience in this research area. Although increased systems engineering activity early in the life cycle is a compelling change for DoD, the findings of the literature review and the survey of practitioners both indicate that there is much to be done in order to position the systems engineering community for success so that the improved defense acquisition outcomes as envisioned by the architects of 2015 DoDI 5000.02 can be realized.