19,945 research outputs found

    Contrasting Views of Complexity and Their Implications For Network-Centric Infrastructures

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    There exists a widely recognized need to better understand and manage complex “systems of systems,” ranging from biology, ecology, and medicine to network-centric technologies. This is motivating the search for universal laws of highly evolved systems and driving demand for new mathematics and methods that are consistent, integrative, and predictive. However, the theoretical frameworks available today are not merely fragmented but sometimes contradictory and incompatible. We argue that complexity arises in highly evolved biological and technological systems primarily to provide mechanisms to create robustness. However, this complexity itself can be a source of new fragility, leading to “robust yet fragile” tradeoffs in system design. We focus on the role of robustness and architecture in networked infrastructures, and we highlight recent advances in the theory of distributed control driven by network technologies. This view of complexity in highly organized technological and biological systems is fundamentally different from the dominant perspective in the mainstream sciences, which downplays function, constraints, and tradeoffs, and tends to minimize the role of organization and design

    Coping with Extreme Events: Institutional Flocking

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    Recent measurements in the North Atlantic confirm that the thermohaline circulation driving the Gulf Stream has come to a stand. Oceanographic monitoring over the last 50 years already showed that the circulation was weakening. Under the influence of the large inflow of melting water in Northern Atlantic waters during last summer, it has now virtually stopped. Consequently, the KNMI and the RIVM estimate the average . In this essay we will explore how such a new risk profile affects the distribution of risks among societal groups, and the way in which governing institutions need to adapt in order to be prepared for situations of rapid but unknown change. The next section will first introduce an analytical perspective, building upon the Risk Society thesis and a proposed model of ‘institutional flocking’.temperature to decrease by 3°C in the next 15 years

    Self-governance in Farmer-managed Irrigation Systems in Nepal

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    Effective governance of natural resources is a key challenge facing many developing nations. There is general agreement that without effective institutions, resources will be underprovided and overused. What is less certain, however, is what these institutions might be and who ought to provide them. Should governments take the lead in supplying institutions and organizing collective action, should this task be resolved through market forces, or should resource users of a "common pool resource" be encouraged to take the lead? This paper presents the view that it is difficult for external actors to design optimal institutions and enforce rules at low cost because solutions tend to be conditional and situation specific. Therefore, local resource users are better equipped to develop or be major participants in developing institutional solutions. Support for this idea is drawn from empirical studies of irrigation systems in Nepal. Comparisons of the performance of farmer-managed irrigation systems with that of agency-managed irrigation systems show that the former consistently out perform the latter on most performance measures. This paper offers two key insights: developing effective institutions is as important as developing physical infrastructure and local resource users may be able to offer better institutional solutions under certain conditions than government agencies when resources are local in scal

    DEPAS: A Decentralized Probabilistic Algorithm for Auto-Scaling

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    The dynamic provisioning of virtualized resources offered by cloud computing infrastructures allows applications deployed in a cloud environment to automatically increase and decrease the amount of used resources. This capability is called auto-scaling and its main purpose is to automatically adjust the scale of the system that is running the application to satisfy the varying workload with minimum resource utilization. The need for auto-scaling is particularly important during workload peaks, in which applications may need to scale up to extremely large-scale systems. Both the research community and the main cloud providers have already developed auto-scaling solutions. However, most research solutions are centralized and not suitable for managing large-scale systems, moreover cloud providers' solutions are bound to the limitations of a specific provider in terms of resource prices, availability, reliability, and connectivity. In this paper we propose DEPAS, a decentralized probabilistic auto-scaling algorithm integrated into a P2P architecture that is cloud provider independent, thus allowing the auto-scaling of services over multiple cloud infrastructures at the same time. Our simulations, which are based on real service traces, show that our approach is capable of: (i) keeping the overall utilization of all the instantiated cloud resources in a target range, (ii) maintaining service response times close to the ones obtained using optimal centralized auto-scaling approaches.Comment: Submitted to Springer Computin

    From Social Data Mining to Forecasting Socio-Economic Crisis

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    Socio-economic data mining has a great potential in terms of gaining a better understanding of problems that our economy and society are facing, such as financial instability, shortages of resources, or conflicts. Without large-scale data mining, progress in these areas seems hard or impossible. Therefore, a suitable, distributed data mining infrastructure and research centers should be built in Europe. It also appears appropriate to build a network of Crisis Observatories. They can be imagined as laboratories devoted to the gathering and processing of enormous volumes of data on both natural systems such as the Earth and its ecosystem, as well as on human techno-socio-economic systems, so as to gain early warnings of impending events. Reality mining provides the chance to adapt more quickly and more accurately to changing situations. Further opportunities arise by individually customized services, which however should be provided in a privacy-respecting way. This requires the development of novel ICT (such as a self- organizing Web), but most likely new legal regulations and suitable institutions as well. As long as such regulations are lacking on a world-wide scale, it is in the public interest that scientists explore what can be done with the huge data available. Big data do have the potential to change or even threaten democratic societies. The same applies to sudden and large-scale failures of ICT systems. Therefore, dealing with data must be done with a large degree of responsibility and care. Self-interests of individuals, companies or institutions have limits, where the public interest is affected, and public interest is not a sufficient justification to violate human rights of individuals. Privacy is a high good, as confidentiality is, and damaging it would have serious side effects for society.Comment: 65 pages, 1 figure, Visioneer White Paper, see http://www.visioneer.ethz.c

    Engineering self-organizing urban superorganisms

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    Progresses in ubiquitous, embedded, and social networking and computing make possible for people in urban areas to dynamically interact with each other and with ICT devices around. This can result in a system with a very large number of agents working together in an orchestrated and self-organizing way to achieve specific urban-level goals, i.e., as if they were a “superorganism”. In this paper, we sketch the future vision of urban superorganisms and overview some emerging application areas heading towards the vision. Following, we identify the key challenges in engineering self-organizing multi-agent systems that can work as a superorganism, i.e., seamlessly involving ICT agents and human agents so to achieve some required urban level goals. Finally, we introduce the reference architecture for an infrastructure to support our future vision of self-organizing urban superorganisms
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