Enabling Flexibility through Forming and Evolving Systems of Systems

Flexibility is a highly desired attribute of many systems operating in changing or uncertain conditions. This paper presents a study of enabling flexibility through designing and operating systems of systems (SoSs). The paper analyzes flexibility mechanisms of SoSs and, accordingly, identifies needs for flexibility that SoSs can meet. Following that, it proposes a hierarchical network as a more flexible SoS architecture for complex or distributed large-scale systems. Then, decision problems for forming and evolving a SoS network are defined. A case that involves integrating distributed renewable energy sources with the main grid is presented to illustrate the implementation of the proposed methodology. Results from this study support the idea of acquiring and maintaining flexibility with SoSs. The paper also identifies research needs for advancing this particular use of SoSs

A Process Improvement Study on a Military System of Clinics to Manage Patient Demand and Resource Utilization Using Discrete-Event Simulation, Sensitivity Analysis, and Cost-Benefit Analysis

Inefficiencies in the healthcare system are a growing concern. Long wait-times are a concern at military clinics because it takes servicemembers away from performing their duties. Managing wait-times are particularly challenging due to frequent relocations of servicemembers and variable patient demands that are less likely to be experienced by civilian clinics. Military clinics must be capable to meet increasing demand when servicemembers require a Deployment Health Assessment; it also needs to be capable of handling an instantaneous surge of walk-ins when a medical incident occurs in the local area. It must be able to meet these demands in a fiscally austere environment. Existing research primarily focuses on stand-alone clinics, whereas this research takes a novel approach of examining a system of clinics, in which some resources are shared. This research evaluates the impacts of variable staffing levels on total wait-time for the system of clinics at baseline demand and when demand increases, using discrete-event simulation, sensitivity analysis, and cost-benefit analysis. This research finds misallocated resources; the wait-time of alternative systems are sensitive to deployment and medical incident demands; and hiring an optometrist while removing an occupational medicine doctor provides the highest savings in baseline, deployment, and medical incident demand environments

A scalable hydrogen propulsion system for civil transport aircraft

The aim of this research was to explore the application of engineering systems evolvability analysis techniques in devising potential scalable hydrogen propulsion systems for future civil transport aircraft. Baseline and derivative aircraft concepts were generated for a medium-sized long-range aircraft, with the derivative options having different levels of hydrogen incorporated in a dual-fuel arrangement (with separate hydrogen and kerosene turbofans), as well as potential turboelectric propulsion with boundary layer ingestion. Commonality between each baseline-derivative pair was then estimated, which could be used to predict the derivative development cost savings that could potentially be obtained when working from a specific baseline. The performance and cost results enabled different future scenarios to be explored. It was shown that developing the future concepts based on an existing state-of-the aircraft as baseline can offer considerable cost savings, as opposed to designing a clean sheet version. The importance of the baseline configuration selection in reducing the development cost for the different hydrogen configurations was also highlighted

Establishing the Foundations to Measure Organizational Agility for Military Organizations

There is an ongoing demand for organizations to become more agile in order to prosper amongst their competitors. Many military organizations have declared a renewed focus towards organizational agility. The goal of this research is to isolate the variables needed to measure organizational agility (OA) in military organizations, allowing for the future development of a suitable method to measure OA without the need to interact with outside organizations. This article begins by providing a suitable and formal definition of organizational agility by exploring and analyzing relevant scholarly literature on the subject. Related terms, such as organizational resiliency, flexibility, robustness, versatility, and adaptability are also explored to examine their definition boundaries and any overlapping areas. Existing methods to measure organizational agility are examined and summarized, and the current limitations to their application are highlighted. Previous studies to find characteristics associated with organizational agility were also examined, and an initial set of 88 organizational agility characteristics was built. Since these included possible redundant or overlapping characteristics, the Q-sort method was employed to discover, analyze, and eliminate redundant items from the dataset, ultimately resulting in 64 unique characteristics. The result is a suitable definition for organization agility applicable to military organizations and a list of potential associated characteristics that summarizes related research to date. This groundwork establishes the foundation to conduct a multi-organization study to further refine the characteristic list and ultimately develop a method to measure organizational agility

Exploring a Method to Quantitatively Measure Design Flexibility Early in the Defense Acquisition Life Cycle

The purpose of this research was to demonstrate a methodology using an Epoch-Era Analysis to quantify and estimate the value of design flexibility early in the Department of Defense\u27s (DOD) acquisition life cycle. This method was implemented using a possible replacement to the Air Force\u27s fighter-trainer aircraft as a baseline and a set of future requirements that would change the baseline. An existing Cost Estimating Relationship tool was utilized in conjunction with a decision tree modeling approach to accommodate uncertain future needs. Sensitivity analysis was performed to identify model parameters with dominant effects on the recommended design strategies. The results indicated that this methodology can quantitatively measure design flexibility using existing tools when key assumptions are made. The methodology exists as a proof of concept within the domain of aircraft to quantitatively measure design flexibility early in the acquisition life cycle. Further research is required to characterize the assumptions of this study and to test this methodology in other domains to validate its broader applicability

Enhancing Set-Based Design To Engineer Resilience For Long-Lived Systems

At the heart of Set-Based Design is the concept that down-select decisions are deferred until sufficient information is available to make a decision, i.e., a set of possible solutions is maintained. Due to the extended service lives of many of our current and future systems, the horizon for accurately predicting the system’s requirement is shorter than the service life, so the needed information to down-select to a single optimized solution is unavailable at the time of fielding. Set-Based Design can, however, be extended to explicitly carry a set of possible solutions past the point of the initial fielding of the system by considering changeability, as enabled through designed-in reserve capacity to accommodate additional volume, weight, power, cooling, and computer performance. Proposed is an analytical framework that enhances Set-Based Design to engineer resilient systems with cost-effective post-production growth capability by means of reserve capacity and illustrate it through a case study

From modularity to emergence: a primer on the design and science of complex systems

Electrical networks, flocking birds, transportation hubs, weather patterns, commercial organisations, swarming robots... Increasingly, many of the systems that we want to engineer or understand are said to be ‘complex’. These systems are often considered to be intractable because of their unpredictability, non-linearity, interconnectivity, heterarchy and ‘emergence’. Such attributes are often framed as a problem, but can also be exploited to encourage systems to efficiently exhibit intelligent, robust, self-organising behaviours. But what does it mean to describe systems as complex? How do these complex systems differ from the more easily understood ‘modular’ systems that we are familiar with? What are the underlying similarities between different systems, whether modular or complex? Answering these questions is a first step in approaching the design and science of complexity. However, to do so, it is necessary to look beyond the specifics of any particular system or field of study. We need to consider the fundamental nature of systems, looking for a common way to view ostensibly different phenomena. This primer introduces a domain-neutral framework and diagrammatic scheme for characterising the ways in which systems are modular or complex. Rather than seeing modularity and complexity as inherent attributes of systems, we instead see them as ways in which those systems are characterised by those who are interested in them. The framework is not tied to any established mode of representation (e.g. networks, equations, formal modelling languages) nor to any domain-specific terminology (e.g. ‘vertex’, ‘eigenvector’, ‘entropy’). Instead, it consists of basic system constructs and three fundamental attributes of modular system architecture, namely structural encapsulation, function-structure mapping and interfacing. These constructs and attributes encourage more precise descriptions of different aspects of complexity (e.g. emergence, self-organisation, heterarchy). This allows researchers and practitioners from different disciplines to share methods, theories and findings related to the design and study of different systems, even when those systems appear superficially dissimilar