Systems Analysis

This paper describes the development of a methodology to import key products of the DoD Architecture Framework into an executable form to conduct a dynamic analysis of the Command and Control (C2) system or capability represented by the architecture. Dynamic analysis of these models enables a user to assess the impact of change and determine measures of performance and effectiveness. The research team successfully implemented the methodology in a demonstration that made a three-way link among a business process model, a communications network model, and a combat simulation representing the system's operational environment. We linked these models together via the Runtime Infrastructure (RTI) of the High Level Architecture (HLA). Basic HLA interactions that we established allowed key events in the combat simulation to initiate one or more business processes in the process model. As a business process proceeded in time, the process model requested from the communications model a de...

The filtered backprojection (FBP) algorithm is widely used in computed tomography for inverting the two-dimensional Radon transform. In this paper, we analyze the processing of an inconsistent data function by the FBP algorithm (in its continuous form). Specifically, we demonstrate that an image reconstructed using the FBP algorithm can be represented as the sum of a pseudoinverse solution and a residual image generated from an inconsistent component of the measured data. This reveals that, when the original data function is in the range of the Radon transform, the image reconstructed using the FBP algorithm corresponds to the pseudoinverse solution. When the data function is inconsistent, we demonstrate that the FBP algorithm makes use of a nonorthogonal projection of the data function to the range of the Radon transform.

Every safety-critical industry devotes considerable time and resource to investigating and analysing accidents, incidents and near misses. The systematic analysis of incidents has greatly expanded our understanding of both the causes and prevention of harm. These methods have been widely employed in healthcare over the last 20 years but are now subject to critique and reassessment. In this paper, we reconsider the purpose and value of incident analysis and methods appropriate to the healthcare of today. The primary need for a revised vision of incident analysis is that healthcare itself is changing dramatically. People are living longer, often with multiple co-morbidities which are managed over very long timescales. Our vision of safety analysis needs to expand concomitantly to embrace much longer timescales. Rather than think only in terms of the prevention of specific incidents, we need to consider the balance of benefit, harm and risks over long time periods encompassing the soci...

... for that taking selected ordering parameters as input is much efficient for modeling. ... Taleb-Bendiab, “Performance Evaluation for Self-Healing Distributed Services and Fault Detection Mechanisms,” Journal ... 4].M. Steinder and AS Sethi, “A Survey of Fault Localization Techniques ...

Medical waste is a nightmare for hospital administrators, cutting across department boundaries and incorporating legal, financial, and community concerns. In this two-part article the author provides a stepwise approach to effective waste management. The first part gives background information on waste generation, storage, and disposal and delineates the framework of a medical waste audit. This audit is put to the test in the second part, where data from a pilot trial at an actual hospital are presented and discussed.

Requirements defects have a major impact throughout the whole software lifecycle. Having a specific defects classification for requirements is important to analyse the root causes of problems, build checklists that support requirements reviews and to reduce risks associated with requirements problems. In our research we analyse several defects classifiers; select the ones applicable to requirements specifications, following rules to build defects taxonomies; and assess the classification validity in an experiment of requirements defects classification performed by graduate and undergraduate students. Not all subjects used the same type of defect to classify the same defect, which suggests that defects classification is not consensual. Considering our results we give recommendations to industry and other researchers on the design of classification schemes and treatment of classification results.

The term resilience has dominated the discourse among health systems researchers since 2014 and the onset of the Ebola outbreak in West Africa. There is wide consensus that the global community has to help build more resilient health systems. But do we really know what resilience means, and do we all have the same vision of resilience? The present paper presents a new conceptual framework on governance of resilience based on systems thinking and complexity theories. In this paper, we see resilience of a health system as its capacity to absorb, adapt and transform when exposed to a shock such as a pandemic, natural disaster or armed conflict and still retain the same control over its structure and functions.

Hospitals often invest significant resources in the development of large and complex information systems that must be modified and extended to respond to changing requirements and to exploit the capabilities offered by modern technologies. A disciplined approach of managing the evolution of hospital information systems is then required so that to meet the increasing demands for effective and efficient use of scarce resources. This paper takes a process oriented view of the hospital and presents an approach based on hospital process modeling which aims at assessing the current status of computer support within a hospital and at identifying new opportunities for automation. The approach is illustrated by an example taken from a major Greek hospital.

The systems approach in education is a management tool that allows individuals to examine all aspects of a problem, to interrelate the effects of one set of decisions to another, and to optimally use the resources at hand to solve the problem. Five systems approaches which have been used in the successful development of instruction at the classroom level can be identified; the Teaching Research Systems Approach, the Michigan State University Instructional Systems Development Model, the System Approach for Education Model, the Project MINERVA Instructional Systems Design Model, and the Banathy Instructional Development System Model. All of these models include actions that fall into the categories of problem definition and organization, systems analysis and development, and system evaluation. These actions are interrelated by feedback built into the model. Each of the different systems approaches, while addressing the same task in similar ways, perform with different descriptions and...

New ways of working in critical care are emerging in response to increasing demands for care in the context of a limited critical care workforce. This review appraised the comparative safety, effectiveness and costs of new ways of working in critical care. All papers published in peer reviewed journals during 1990-2003 were utilised. A total of 933 potentially relevant papers were identified. Secondary sources including policy papers, and experts within the field were also used to inform this work. Initially 113 papers met the inclusion criteria. However, 58 of these described policy and secular trends in critical care and were therefore used only to provide background information. A total of 55 papers were then critically reviewed to provide academic focus on the subject area. Examples of comparative empirical research on new ways of working were limited, but the review revealed research activity in the areas of: impact of workload; nursing, medical and organisational factors affec...

The authors have experimented the application of the Failure Mode and Effect Analysis (FMEA) technique in a clinical laboratory. FMEA technique allows: a) to evaluate and measure the hazards of a process malfunction, b) to decide where to execute improvement actions, and c) to measure the outcome of those actions. A small sample of analytes has been studied: there have been determined the causes of the possible malfunctions of the analytical process, calculating the risk probability index (RPI), with a value between 1 and 1,000. Only for the cases of RPI > 400, improvement actions have been implemented that allowed a reduction of RPI values between 25% to 70% with a costs increment of < 1%. FMEA technique can be applied to the processes of a clinical laboratory, even if of small dimensions, and offers a high potential of improvement. Nevertheless, such activity needs a thorough planning because it is complex, even if the laboratory already operates an ISO 9000 Quality Manageme...

This paper describes how to use a positive deviance-inspired process for improving the practice of systems engineering, and how positive deviance fits into an evolutionary improvement strategy. It illustrates the process with examples from both systems engineering and cases studies outside of systems engineering. In particular we cite the experience of the team that authored the DoD systems engineering guide for systems of systems (SoS) [Ref 1]. They developed a representation of how successful SoS engineering practitioners view and do systems engineering that is substantially different from their individual system counterparts. The cases outside of systems engineering relate to an antistarvation program in rural Vietnam and a 150-year old problem of inadequate hand scrubbing and infections in hospitals [Ref 2]. Even with substantial progress in technology, processes, and efficiencies, complex problems from enterprise systems engineering to nutrition to medical needs still stubbornly resist improvement. By using a positive deviance-inspired approach, this can be reversed.