International Journal of System of Systems Engineering http://www.inderscience.com/browse/index.php?journalID=184&year=2011&vol=2&issue=4 Inderscience Publishers Ltd en-uk International Journal of System of Systems Engineering 1748-0671 1748-068X © 2011 Inderscience Publishers Ltd editor@inderscience.com https://www.inderscience.com/images/files/coverImgs/ijsse_scoverijsse.jpg http://www.inderscience.com/browse/index.php?journalID=184&year=2011&vol=2&issue=4 http://www.inderscience.com/link.php?id=43860 The complexity of new technology and operational changes to reduce manning on the Navy warfighter require that system-of-systems methodologies be used to make engineering, workflow, and policy decisions. However, system-of-systems models contain hundreds of factors and account for many outputs, which make it difficult to utilise the model for decision making. Sensitivity analysis is applied to a system-of-systems Navy warfighter simulation model incorporating the crew, concept of operations, and various ship systems to identify the critical factors and their directional effect on all the outputs. The emergent phenomena of the system-of-systems are discovered from the higher order effects of the sensitivity analysis and are examined in the frequency domain to understand these phenomena. It is shown that the second order effect between intelligence maintenance and repair procedures influences the frequency range associated with the crew rotations, task assignments, and machine failures non-linearly. A process to comprehend critical system-of-systems factors: applied to wireless technology design on a navy ship
Shawn McKay; Vishal Mahulkar; Douglas Adams
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 257 - 278
The complexity of new technology and operational changes to reduce manning on the Navy warfighter require that system-of-systems methodologies be used to make engineering, workflow, and policy decisions. However, system-of-systems models contain hundreds of factors and account for many outputs, which make it difficult to utilise the model for decision making. Sensitivity analysis is applied to a system-of-systems Navy warfighter simulation model incorporating the crew, concept of operations, and various ship systems to identify the critical factors and their directional effect on all the outputs. The emergent phenomena of the system-of-systems are discovered from the higher order effects of the sensitivity analysis and are examined in the frequency domain to understand these phenomena. It is shown that the second order effect between intelligence maintenance and repair procedures influences the frequency range associated with the crew rotations, task assignments, and machine failures non-linearly.

]]> 10.1504/IJSSE.2011.043860 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 257 - 278 Shawn McKay; Vishal Mahulkar; Douglas Adams 1500 Kepner Dr. Lafayette, IN 47905, USA. ' 1500 Kepner Dr. Lafayette, IN 47905, USA. ' 1500 Kepner Dr. Lafayette, IN 47905, USA system of systems agent-based modelling sensitivity analysis complexity emergent phenomena frequency domain analysis multi-agent systems agent-based systems naval ships navy warships decision making simulation modelling intelligent maintenance intelligent repair crew rotation task assignment machine failure wireless technology. 2011-11-25T23:20:50-05:00 2 4 257 278 2011-11-25T23:20:50-05:00 http://www.inderscience.com/link.php?id=43864 For discrete-time linear systems, controllability and reachability are not equivalent. Instead of the well-known Kalman's rank condition, which characterises reachability, controllability to origin of the time invariant, discrete-time linear system is equivalent to the Fuhrmann's rank condition. In the first part of this paper, we prove that controllability to origin of time varying discrete-time linear systems, under a difference-algebraic condition, is equivalent to a generalised Fuhrmann's rank condition. In the second part, we prove that reachability and observability for time varying discrete-time linear systems are equivalent to a structured Kalman's rank condition, under the difference algebraic independence of the structure matrices. A generalisation of Fuhrmann's rank condition for discrete dynamic systems
Sándor Molnár; Ferenc Szigeti
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 279 - 289
For discrete-time linear systems, controllability and reachability are not equivalent. Instead of the well-known Kalman's rank condition, which characterises reachability, controllability to origin of the time invariant, discrete-time linear system is equivalent to the Fuhrmann's rank condition. In the first part of this paper, we prove that controllability to origin of time varying discrete-time linear systems, under a difference-algebraic condition, is equivalent to a generalised Fuhrmann's rank condition. In the second part, we prove that reachability and observability for time varying discrete-time linear systems are equivalent to a structured Kalman's rank condition, under the difference algebraic independence of the structure matrices.

]]> 10.1504/IJSSE.2011.043864 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 279 - 289 Sándor Molnár; Ferenc Szigeti Department of Informatics, Szent Istvan University, H-2103 Gödöllö, Páter K. u.1., Hungary. ' Department of Control Engineering, University of los Andes, Merida, Venezuela discrete time linear systems difference algebraic conditions rank condition reachability controllability. 2011-11-25T23:20:50-05:00 2 4 279 289 2011-11-25T23:20:50-05:00 http://www.inderscience.com/link.php?id=43861 Healthcare systems face increasing demands and reduced resources. Therefore, there is growing attention paid to sustainability in healthcare. Healthcare is a complex system of systems. This paper discusses healthcare system challenges and the need to consider a sustainable approach in addressing these challenges. An equitable and balanced approach is required to deal with the demands related to healthcare sustainability including societal needs, financial constraints, and intensifying environmental expectations. System dynamics, a systems thinking approach, is applied to help address the challenges of complexity, variability, and uncertainty related to a sustainable model for healthcare. Causal models illustrating the system dynamics factors and relationships are presented. Analysis of the system dynamics and associated factors produced a notional set of healthcare sustainability indicators. These indicators provide important measures of healthcare sustainability. Applying systems thinking to assess sustainability in healthcare system of systems
Misagh Faezipour; Susan Ferreira
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 290 - 308
Healthcare systems face increasing demands and reduced resources. Therefore, there is growing attention paid to sustainability in healthcare. Healthcare is a complex system of systems. This paper discusses healthcare system challenges and the need to consider a sustainable approach in addressing these challenges. An equitable and balanced approach is required to deal with the demands related to healthcare sustainability including societal needs, financial constraints, and intensifying environmental expectations. System dynamics, a systems thinking approach, is applied to help address the challenges of complexity, variability, and uncertainty related to a sustainable model for healthcare. Causal models illustrating the system dynamics factors and relationships are presented. Analysis of the system dynamics and associated factors produced a notional set of healthcare sustainability indicators. These indicators provide important measures of healthcare sustainability.

]]> 10.1504/IJSSE.2011.043861 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 290 - 308 Misagh Faezipour; Susan Ferreira Systems Engineering Research Center, The University of Texas at Arlington, 500 W. First St., 420 Woolf Hall, Arlington, Texas, USA. ' Systems Engineering Research Center, The University of Texas at Arlington, 500 W. First St., 420 Woolf Hall, Arlington, Texas, USA healthcare systems system of systems systems thinking system dynamics causal models sustainability indicators sustainable development societal needs financial constraints environmental expectations complexity variability uncertainty. 2011-11-25T23:20:50-05:00 2 4 290 308 2011-11-25T23:20:50-05:00 http://www.inderscience.com/link.php?id=43862 To implement computationally-intensive tasks, typically, various levels of parallelism are used. Depending on the applications, the best possible results are produced by different parallelism approaches. Pipelining is an example of hardware-implemented parallelism; multithreading is effective for the software that supports it. In this paper, we propose a fuzzy logic algorithm for dynamic load balancing in a distributed cluster performing 3D video rendering for a simulated robotic vision tests. We present results taken from a production processing environment, rather than simulations. We have tested the algorithm within comprehensive virtual reality simulator Initiative Software Earth (ISE), a project of Computer Engineering Framework (CEF). The experimental results gathered on 50+ Linux cluster, demonstrate that the proposed approach performs better compared to conventional methods such as static and gradient load balancing. Temporal-spatial fuzzy logic algorithm for effective dynamic load balancing in distributed 3D graphics engine
Aleksandr Panchul; David Akopian; Mo Jamshidi
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 309 - 328
To implement computationally-intensive tasks, typically, various levels of parallelism are used. Depending on the applications, the best possible results are produced by different parallelism approaches. Pipelining is an example of hardware-implemented parallelism; multithreading is effective for the software that supports it. In this paper, we propose a fuzzy logic algorithm for dynamic load balancing in a distributed cluster performing 3D video rendering for a simulated robotic vision tests. We present results taken from a production processing environment, rather than simulations. We have tested the algorithm within comprehensive virtual reality simulator Initiative Software Earth (ISE), a project of Computer Engineering Framework (CEF). The experimental results gathered on 50+ Linux cluster, demonstrate that the proposed approach performs better compared to conventional methods such as static and gradient load balancing.

]]> 10.1504/IJSSE.2011.043862 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 309 - 328 Aleksandr Panchul; David Akopian; Mo Jamshidi Department of Electrical and Computer Engineering, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA. ' Department of Electrical and Computer Engineering, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA. ' Department of Electrical and Computer Engineering, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA distributed computing dynamic load balancing 3D video rendering fuzzy logic cloud computing distributed graphics 3D graphics engine robot vision production processes virtual reality. 2011-11-25T23:20:50-05:00 2 4 309 328 2011-11-25T23:20:50-05:00 http://www.inderscience.com/link.php?id=43863 Climate change is at the forefront of scientific investigation and socio-political decision-making. The world community of scientists concur with the fact that human activities are both contributing to and affected by changes in the environment that influence the overall well-being of the world population. Importantly, these changes do not discriminate as to region or inhabitants. The body of research has measured climate change via modelling that incorporates the laws of physics and climate data. Neglected in these models is a significant factor: the global human population is increasing at an unprecedented rate that will further stress these geological and ecological variations. This research proffers a complex-systems modelling methodology for climate change to assess current and future concerns, intricately linked facets or pieces, of the human-environment relationship. It requires an interdisciplinary approach to research and model development that combines expertise from the social sciences and disciplines. Assessing the human-environment relationship: a complex-systems methodology to modelling climate change
Catherine M. Banks; John A. Sokolowski
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 329 - 346
Climate change is at the forefront of scientific investigation and socio-political decision-making. The world community of scientists concur with the fact that human activities are both contributing to and affected by changes in the environment that influence the overall well-being of the world population. Importantly, these changes do not discriminate as to region or inhabitants. The body of research has measured climate change via modelling that incorporates the laws of physics and climate data. Neglected in these models is a significant factor: the global human population is increasing at an unprecedented rate that will further stress these geological and ecological variations. This research proffers a complex-systems modelling methodology for climate change to assess current and future concerns, intricately linked facets or pieces, of the human-environment relationship. It requires an interdisciplinary approach to research and model development that combines expertise from the social sciences and disciplines.

]]> 10.1504/IJSSE.2011.043863 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 329 - 346 Catherine M. Banks; John A. Sokolowski Virginia Modeling, Analysis and Simulation Center (VMASC), Old Dominion University, 1030 University Boulevard, Suffolk, Virginia 23425, USA. ' Virginia Modeling, Analysis and Simulation Center (VMASC), Old Dominion University, 1030 University Boulevard, Suffolk, Virginia 23425, USA circular interdependencies holistic representation internally displaced persons population dynamics social network modelling global citizens food security mapping change indices climate change complex systems human-environment relationship. 2011-11-25T23:20:50-05:00 2 4 329 346 2011-11-25T23:20:50-05:00 http://www.inderscience.com/link.php?id=43865 This note introduces forensic complexity as a multidisciplinary approach to the study of comprehension in complex situations in order to enable justifiable action. The term itself seems paradoxical when viewed as analysis of the unpredictable or irreducible. The paradox is resolved by the adoption of an internally consistent perspective for complex situations referred to as a complex situations paradigm (Brewer, 2010), based on the pragmatic idealism of Sousa-Poza and Correa-Martinez (2005). This paradigm shifts the perspective from complexity to the nature of complexity (e.g., a meta-discussion), providing a basis to discuss analysis of characteristics of complexity with respect to decision making. A brief review of complexity provides the elements to incorporate the relationships essential to understanding and decision making processes. This is followed by a précis of the complex situations paradigm, which frames the proposed definition of forensic complexity. This concept provides a basis for continued dialog, and invites further multidisciplinary research. Forensic complexity
Van Brewer; Adrian Gheorghe
International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 347 - 355
This note introduces forensic complexity as a multidisciplinary approach to the study of comprehension in complex situations in order to enable justifiable action. The term itself seems paradoxical when viewed as analysis of the unpredictable or irreducible. The paradox is resolved by the adoption of an internally consistent perspective for complex situations referred to as a complex situations paradigm (Brewer, 2010), based on the pragmatic idealism of Sousa-Poza and Correa-Martinez (2005). This paradigm shifts the perspective from complexity to the nature of complexity (e.g., a meta-discussion), providing a basis to discuss analysis of characteristics of complexity with respect to decision making. A brief review of complexity provides the elements to incorporate the relationships essential to understanding and decision making processes. This is followed by a précis of the complex situations paradigm, which frames the proposed definition of forensic complexity. This concept provides a basis for continued dialog, and invites further multidisciplinary research.

]]> 10.1504/IJSSE.2011.043865 International Journal of System of Systems Engineering, Vol. 2, No. 4 (2011) pp. 347 - 355 Van Brewer; Adrian Gheorghe Old Dominion Research Foundation, Suite 406 (NCSOSE), 4111 Monarch Way, Norfolk, VA 23508 USA. ' Batten Chair of Systems Engineering, Department of Engineering Management and Systems Engineering, 242C Kaufman Hall, Norfolk, Virginia 23529 USA forensic complexity complex situations paradigm decision making multidisciplinary research. 2011-11-25T23:20:50-05:00 2 4 347 355 2011-11-25T23:20:50-05:00