WorldWideScience

Sample records for self-organizing urban systems

  1. Scaling laws and indications of self-organized criticality in urban systems

    International Nuclear Information System (INIS)

    Chen Yanguang; Zhou Yixing

    2008-01-01

    Evolution of urban systems has been considered to exhibit some form of self-organized criticality (SOC) in the literature. This paper provides further mathematical foundations and empirical evidences to support the supposition. The hierarchical structure of systems of cities can be formulated as three exponential functions: the number law, the population size law, and the area law. These laws are identical in form to the Horton-Strahler laws of rivers and Gutenberg-Richter laws of earthquakes. From the exponential functions, three indications of SOC are also derived: the frequency-spectrum relation indicting the 1/f noise, the power laws indicating the fractal structure, and the Zipf's law indicating the rank-size distribution. These mathematical models form a set of scaling laws for urban systems, as demonstrated in the empirical study of the system of cities in China. The fact that the scaling laws of urban systems bear an analogy to those on rivers and earthquakes lends further support to the notion of possible SOC in urban systems

  2. Self-organized criticality and urban development

    Directory of Open Access Journals (Sweden)

    Michael Batty

    1999-01-01

    Full Text Available Urban society is undergoing as profound a spatial transformation as that associated with the emergence of the industrial city two centuries ago. To describe and measure this transition, we introduce a new theory based on the concept that large-scale, complex systems composed of many interacting elements, show a surprising degree of resilience to change, holding themselves at critical levels for long periods until conditions emerge which move the system, often abruptly, to a new threshold. This theory is called ‘self-organized criticality’; it is consistent with systems in which global patterns emerge from local action which is the hallmark of self-organization, and it is consistent with developments in system dynamics and their morphology which find expression in fractal geometry and weak chaos theory. We illustrate the theory using a unique space–time series of urban development for Buffalo, Western New York, which contains the locations of over one quarter of a million sites coded by their year of construction and dating back to 1773, some 60 years before the city began to develop. We measure the emergence and growth of the city using urban density functions from which measures of fractal dimension are used to construct growth paths of the way the city has grown to fill its region. These phase portraits suggest the existence of transitions between the frontier, the settled agricultural region, the centralized industrial city and the decentralized postindustrial city, and our analysis reveals that Buffalo has maintained itself at a critical threshold since the emergence of the automobile city some 70 years ago. Our implied speculation is: how long will this kind of urban form be maintained in the face of seemingly unstoppable technological change?

  3. Self-Organized Transport System

    Science.gov (United States)

    2009-09-28

    This report presents the findings of the simulation model for a self-organized transport system where traffic lights communicate with neighboring traffic lights and make decisions locally to adapt to traffic conditions in real time. The model is insp...

  4. Complex Systems and Self-organization Modelling

    CERN Document Server

    Bertelle, Cyrille; Kadri-Dahmani, Hakima

    2009-01-01

    The concern of this book is the use of emergent computing and self-organization modelling within various applications of complex systems. The authors focus their attention both on the innovative concepts and implementations in order to model self-organizations, but also on the relevant applicative domains in which they can be used efficiently. This book is the outcome of a workshop meeting within ESM 2006 (Eurosis), held in Toulouse, France in October 2006.

  5. Control of self-organizing nonlinear systems

    CERN Document Server

    Klapp, Sabine; Hövel, Philipp

    2016-01-01

    The book summarizes the state-of-the-art of research on control of self-organizing nonlinear systems with contributions from leading international experts in the field. The first focus concerns recent methodological developments including control of networks and of noisy and time-delayed systems. As a second focus, the book features emerging concepts of application including control of quantum systems, soft condensed matter, and biological systems. Special topics reflecting the active research in the field are the analysis and control of chimera states in classical networks and in quantum systems, the mathematical treatment of multiscale systems, the control of colloidal and quantum transport, the control of epidemics and of neural network dynamics.

  6. Self-organization in interface dynamics and urban development

    OpenAIRE

    Meron, Ehud

    1999-01-01

    The view of the urban environment as an extended nonlinear system introduces new concepts, motivates new questions, and suggests new methodologies in the study of urban dynamics. A review of recent results on interface dynamics in nonequilibrium physical systems is presented, and possible implications on the urban environment are discussed. It is suggested that the growth modes of specific urban zones (e.g. residential, commercial, or industrial) and the factors affecting them can be studied ...

  7. Self-organization in interface dynamics and urban development

    Directory of Open Access Journals (Sweden)

    Ehud Meron

    1999-01-01

    Full Text Available The view of the urban environment as an extended nonlinear system introduces new concepts, motivates new questions, and suggests new methodologies in the study of urban dynamics. A review of recent results on interface dynamics in nonequilibrium physical systems is presented, and possible implications on the urban environment are discussed. It is suggested that the growth modes of specific urban zones (e.g. residential, commercial, or industrial and the factors affecting them can be studied using mathematical models that capture two generic interface instabilities.

  8. The role of hierarchy in self-organizing systems

    NARCIS (Netherlands)

    Ollfen, van W.; Romme, A.G.L.

    1995-01-01

    This paper discusses the role of hierarchy in human systems. Two kinds of self-organizing processes are distinguished: conservative and dissipative self-organization. The former leads to rather stable, specialistic systems, whereas the latter leads to continuously changing generalistic systems. When

  9. Enabling Self-Organization in Embedded Systems with Reconfigurable Hardware

    Directory of Open Access Journals (Sweden)

    Christophe Bobda

    2009-01-01

    Full Text Available We present a methodology based on self-organization to manage resources in networked embedded systems based on reconfigurable hardware. Two points are detailed in this paper, the monitoring system used to analyse the system and the Local Marketplaces Global Symbiosis (LMGS concept defined for self-organization of dynamically reconfigurable nodes.

  10. Functional self-organization in complex systems

    Energy Technology Data Exchange (ETDEWEB)

    Fontana, W. (Los Alamos National Lab., NM (USA) Santa Fe Inst., NM (USA))

    1990-01-01

    A novel approach to functional self-organization is presented. It consists of a universe generated by a formal language that defines objects (=programs), their meaning (=functions), and their interactions (=composition). Results obtained so far are briefly discussed. 17 refs., 5 figs.

  11. The concept of self-organizing systems. Why bother?

    Science.gov (United States)

    Elverfeldt, Kirsten v.; Embleton-Hamann, Christine; Slaymaker, Olav

    2016-04-01

    Complexity theory and the concept of self-organizing systems provide a rather challenging conceptual framework for explaining earth systems change. Self-organization - understood as the aggregate processes internal to an environmental system that lead to a distinctive spatial or temporal organization - reduces the possibility of implicating a specific process as being causal, and it poses some restrictions on the idea that external drivers cause a system to change. The concept of self-organizing systems suggests that many phenomena result from an orchestration of different mechanisms, so that no causal role can be assigned to an individual factor or process. The idea that system change can be due to system-internal processes of self-organization thus proves a huge challenge to earth system research, especially in the context of global environmental change. In order to understand the concept's implications for the Earth Sciences, we need to know the characteristics of self-organizing systems and how to discern self-organizing systems. Within the talk, we aim firstly at characterizing self-organizing systems, and secondly at highlighting the advantages and difficulties of the concept within earth system sciences. The presentation concludes that: - The concept of self-organizing systems proves especially fruitful for small-scale earth surface systems. Beach cusps and patterned ground are only two of several other prime examples of self-organizing earth surface systems. They display characteristics of self-organization like (i) system-wide order from local interactions, (ii) symmetry breaking, (iii) distributed control, (iv) robustness and resilience, (v) nonlinearity and feedbacks, (vi) organizational closure, (vii) adaptation, and (viii) variation and selection. - It is comparatively easy to discern self-organization in small-scale systems, but to adapt the concept to larger scale systems relevant to global environmental change research is more difficult: Self-organizing

  12. Self-Organization, Urban Transformation, and Spatial Planning in Greater Jakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Yovi Dzulhijjah Rahmawati

    2015-09-01

    Full Text Available Penelitian ini bertujuan untuk mengidentifikasi peran sistem perencanaan tata ruang dalam menghadapi proses perorganisasian diri, sebagaimana dibuktikan oleh transformasi perkotaan yang kompleks di wilayah Jakarta. Wilayah Jakarta adalah salah satu wilayah megapolitan di Asia Tenggara yang mengalami proses transformasi yang cepat. Sangat disayangkan bahwa sistem perencanaan tata ruang yang ada sekarang di wilayah Jakarta belum mampu merespon transformasi kota secara non-linier. Kekurangan ini terbukti dari ketidaksinkronan antara dokumen-dokumen perencanaan tata ruang dan perubahan tata guna lahan perkotaan yang diperkuat dengan proses pengorganisasian diri. Perbedaan antara situasi empiris dan dokumen-dokumen perencanaan tata ruang yang ada telah menghasilkan ketidakcocokan antara sistem perencanaan tata ruang dengan sistem tata ruang di wilayah Jakarta. Ketidakcocokan ini terjadi karena sistem perencanaan tata ruang saat ini tidak mempertimbangkan ketidakpastian di masa depan. Situasi ini mengindikasikan adanya ‘fuzziness’ dalam implementasi sistem dan proses perencanaan tata ruang, sementara transformasi perkotaan telah berkembang sedemikian kompleksnya dan membutuhkan respon yang cepat dan tepat. Untuk dapat merespon ketidakcocokan ini, sistem perencanaan tata ruang di wilayah Jakarta harus lebih memperhatikan sistem perkotaan yang berkembang dalam proses yang tidak linear.Kata kunci. Pengorganisasian diri, transformasi perkotaan, ketidaklinieran, sistem perencanaan, Megapolitan Jakarta. This study aimed to identify the role of spatial planning in facing self-organizing processes as evidenced by a complex urban transformation in Greater Jakarta. Greater Jakarta is one of the mega urban-regions in Southeast Asia that are undergoing a rapid urban transformation process. This urban transformation has been developing through a non-linear transition. Unfortunately, the current spatial planning system in Greater Jakarta is not yet adequately

  13. Self-Organization in Embedded Real-Time Systems

    CERN Document Server

    Brinkschulte, Uwe; Rettberg, Achim

    2013-01-01

    This book describes the emerging field of self-organizing, multicore, distributed and real-time embedded systemsSelf-organization of both hardware and software can be a key technique to handle the growing complexity of modern computing systems. Distributed systems running hundreds of tasks on dozens of processors, each equipped with multiple cores, requires self-organization principles to ensure efficient and reliable operation. This book addresses various, so-called Self-X features such as self-configuration, self-optimization, self-adaptation, self-healing and self-protection. Presents open components for embedded real-time adaptive and self-organizing applications; Describes innovative techniques in: scheduling, memory management, quality of service, communications supporting organic real-time applications; Covers multi-/many-core embedded systems supporting real-time adaptive systems and power-aware, adaptive hardware and software systems; Includes case studies of open embedded real-time self-organizi...

  14. Self-Organized Fission Control for Flocking System

    Directory of Open Access Journals (Sweden)

    Mingyong Liu

    2015-01-01

    Full Text Available This paper studies the self-organized fission control problem for flocking system. Motivated by the fission behavior of biological flocks, information coupling degree (ICD is firstly designed to represent the interaction intensity between individuals. Then, from the information transfer perspective, a “maximum-ICD” based pairwise interaction rule is proposed to realize the directional information propagation within the flock. Together with the “separation/alignment/cohesion” rules, a self-organized fission control algorithm is established that achieves the spontaneous splitting of flocking system under conflict external stimuli. Finally, numerical simulations are provided to demonstrate the effectiveness of the proposed algorithm.

  15. Self-organizing energy-autonomous systems

    OpenAIRE

    Liu, Q.

    2016-01-01

    With the rapid development of mobile technology, more and more devices connect to the Internet of Things (IoT). The management of such large-scale networks becomes a challenge. Firstly, a large number of heterogeneous devices are distributed over a wide area, leading to a variation of the requirements of users, the performance of mobile devices, and the application scenarios. As the size of the IoT increases, the complexity of controlling such systems becomes a challenge. Most existing soluti...

  16. When Self-Organization intersects with Urban Planning: Two Cases from Helsinki

    DEFF Research Database (Denmark)

    Horelli, Liisa; Saad-Sulonen, Joanna; Wallin, Sirkku

    2015-01-01

    Participation as self-organization has emerged as a new form of citizen activism, often supported by digital technology. A comparative qualitative analysis of two case studies in Helsinki indicates that the self-organization of citizens expands the practice of urban planning. Together, they enable...... the mobilization of different groups around issues related to urban space. The consequences have become visible in temporary uses of places, event making and community development through bottom-up cultures. However, the lacking links to decision-making constrains new solutions and creative actions....

  17. Negotiation and Design for the Self-Organizing City. Gaming as a method for Urban Design

    Directory of Open Access Journals (Sweden)

    Ekim Tan

    2014-08-01

    Full Text Available An understanding of cities as open systems whose agents act on them simultaneously from below and above, influencing urban processes by their interaction with them and with each other, is replacing the simplistic debate on urban participation which asks whether cities should be organized bottom-up or top-down. This conceptualization of cities as complex systems calls for new collaborative city-making methods: a combination of collaborative planning (which already embraces various agencies and derives decision-making from negotiations between them and collaborative design (existing methods rely on rule-based iterative processes which control spatial outcomes. While current collaborative planning methods are open and interactive, they fail to simulate realistic power negotiations in the evolution of the physical environments they plan; collaborative design methods fall short in modelling the decision-making mechanisms of the physical environments they control. This research is dedicated to building an open negotiation and design method for cities as self-organizing systems that bridges this gap. Gaming as a tool for knowledge creation and negotiation serves as an interface between the more abstract decision-making and material city-making. Rarely involved in the creation of our environment, it has the unexplored potential of combining the socio-spatial dimensions of self-organizing urban processes. Diverse agents, the collaborations and conflicts within and between interest groups, and the parameters provided by topological data can all be combined in an operational form in gaming: potentially a great unifier of multiple stakeholder negotiations and individual design aspirations through which to generate popularly informed policies or design. The simple language and rules of games will allow jargon-free communication between stakeholders, experts and non-experts alike. The interactive and iterative nature of city gaming encourages the development

  18. Research on Corporate Social Responsibility of Supply Chain System Based on the Self-organization Theory

    OpenAIRE

    Baoying Wang

    2013-01-01

    In this study, the characteristics of supply chain system are analyzed based on the Self-organization theory from the angle of view of supply chain system. The mathematical models when the system fulfilling social responsibility including self-organization evolution model and self-organization function model are developed to discuss the formation and function of self-organization in supply chain system and coordination. Some basic conditions and tactics about self-organization establishment a...

  19. Exploring the patterns and evolution of self-organized urban street networks through modeling

    Science.gov (United States)

    Rui, Yikang; Ban, Yifang; Wang, Jiechen; Haas, Jan

    2013-03-01

    As one of the most important subsystems in cities, urban street networks have recently been well studied by using the approach of complex networks. This paper proposes a growing model for self-organized urban street networks. The model involves a competition among new centers with different values of attraction radius and a local optimal principle of both geometrical and topological factors. We find that with the model growth, the local optimization in the connection process and appropriate probability for the loop construction well reflect the evolution strategy in real-world cities. Moreover, different values of attraction radius in centers competition process lead to morphological change in patterns including urban network, polycentric and monocentric structures. The model succeeds in reproducing a large diversity of road network patterns by varying parameters. The similarity between the properties of our model and empirical results implies that a simple universal growth mechanism exists in self-organized cities.

  20. On self-organized criticality in nonconserving systems

    International Nuclear Information System (INIS)

    Socolar, J.E.S.; Grinstein, G.; Jayaprakash, C.

    1993-01-01

    Two models with nonconserving dynamics and slow continuous deterministic driving, a stick-slip model (SSM) of earthquake dynamics and a toy forest-fire model (FFM), have recently been argued to show numerical evidence of self-organized criticality (generic, scale-invariant steady states). To determine whether the observed criticality is indeed generic, we study these models as a function of a parameter γ which was implicitly tuned to a special value, γ=1, in their original definitions. In both cases, the maximum Lyapunov exponent vanishes at γ=1. We find that the FFM does not exhibit self-organized criticality for any γ, including γ=1; nor does the SSM with periodic boundary conditions. Both models show evidence of macroscopic periodic oscillations in time for some range of γ values. We suggest that such oscillations may provide a mechanism for the generation of scale-invariant structure in nonconserving systems, and, in particular, that they underlie the criticality previously observed in the SSM with open boundary conditions

  1. Architectural Patterns for Self-Organizing Systems-of-Systems

    Science.gov (United States)

    2011-05-01

    show that they are necessary for self-organization to occur. Common Purpose Abraham Maslow proposed a theory on human motivation based on a hierarchy...http://www.hole-in-the-wall.com/abouthiwel.html (accessed October 28, 2010). 21. Maslow , Abraham . 1943. A theory of human motivation. In Psychological...in-the-wall Education Ltd. http://www.hole- in-the-wall.com/abouthiwel.html (accessed October 28, 2010). 22. Maslow , Abraham . 1943. A theory of human

  2. IDENTIFYING LOCAL SCALE CLIMATE ZONES OF URBAN HEAT ISLAND FROM HJ-1B SATELLITE DATA USING SELF-ORGANIZING MAPS

    Directory of Open Access Journals (Sweden)

    C. Z. Wei

    2016-10-01

    Full Text Available With the increasing acceleration of urbanization, the degeneration of the environment and the Urban Heat Island (UHI has attracted more and more attention. Quantitative delineation of UHI has become crucial for a better understanding of the interregional interaction between urbanization processes and the urban environment system. First of all, our study used medium resolution Chinese satellite data-HJ-1B as the Earth Observation data source to derive parameters, including the percentage of Impervious Surface Areas, Land Surface Temperature, Land Surface Albedo, Normalized Differential Vegetation Index, and object edge detector indicators (Mean of Inner Border, Mean of Outer border in the city of Guangzhou, China. Secondly, in order to establish a model to delineate the local climate zones of UHI, we used the Principal Component Analysis to explore the correlations between all these parameters, and estimate their contributions to the principal components of UHI zones. Finally, depending on the results of the PCA, we chose the most suitable parameters to classify the urban climate zones based on a Self-Organization Map (SOM. The results show that all six parameters are closely correlated with each other and have a high percentage of cumulative (95% in the first two principal components. Therefore, the SOM algorithm automatically categorized the city of Guangzhou into five classes of UHI zones using these six spectral, structural and climate parameters as inputs. UHI zones have distinguishable physical characteristics, and could potentially help to provide the basis and decision support for further sustainable urban planning.

  3. A self-organized system of smart preys and predators

    Energy Technology Data Exchange (ETDEWEB)

    Rozenfeld, Alejandro F. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, UNLP, CONICET, Suc. 4, C.C. 16 (1900) La Plata (Argentina); Albano, Ezequiel V. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, UNLP, CONICET, Suc. 4, C.C. 16 (1900) La Plata (Argentina)]. E-mail: ealbano@inifta.unlp.edu.ar

    2004-11-22

    Based on the fact that, a standard prey-predator model (SPPM), exhibits irreversible phase transitions, belonging to the universality class of directed percolation (DP), between prey-predator coexistence and predator extinction [Phys. Lett. A 280 (2001) 45], a self-organized prey-predator model (SOPPM) is formulated and studied by means of extensive Monte Carlo simulations. The SOPPM is achieved defining the parameters of the SPPM as functions of the density of species. It is shown that the SOPPM self-organizes into an active state close the absorbing phase of the SPPM, and consequently their avalanche exponents also belong to the universality class of DP.

  4. Magnetic reconnection and self-organized plasma systems

    International Nuclear Information System (INIS)

    Yamada, Masaaki; Ji, Hantao

    2000-01-01

    In this paper the recent results from the Magnetic Reconnection Experiment (MRX) at PPPL are discussed along with their relationship to observations from solar flares, the magnetosphere, and current carrying pinch discharges such as tokamaks, reversed field pinches, spheromaks and field reversed configurations. It is found that the reconnection speed decreases as the angle of merging field lines decreases, consistent with the well-established observation in the dayside magnetosphere. This observation can also provide a qualitative interpretation of a generally observed trend in pinch plasmas, namely that magnetic field diffuses (or reconnects) faster when magnetic shear is larger. A recently conceived research project, SPIRIT (Self-organized Plasma with Induction, Reconnection, and Injection Techniques), will also be discussed. (author)

  5. Self-organization scenario acting as physical basis of intelligent complex systems created in laboratory

    International Nuclear Information System (INIS)

    Lozneanu, Erzilia; Sanduloviciu, Mircea

    2006-01-01

    The recognition of limits in the tendency to miniaturize the so-called self-organizing devices inspired scientists to seek inspiration from living organisms that operate with functional elements that employ thermal energy exploiting quantum phenomena. Here we show how such operations are performed by a complex space charge configuration emerged by self-organization in plasma. Endowed with a special kind of memory, the complexity is able to ensure its survival in a metastable state performing the operations 'learned' during its emergence by self-organization. Possessing memory, the complexity works as an intelligent system able to evolve under suitable environmental conditions

  6. Free Energy Rate Density and Self-organization in Complex Systems

    OpenAIRE

    Georgiev, Georgi Yordanov; Gombos, Erin; Bates, Timothy; Henry, Kaitlin; Casey, Alexander; Daly, Michael

    2015-01-01

    One of the most important tasks in science is to understand the self-organization's arrow of time. To attempt this we utilize the connection between self-organization and non-equilibrium thermodynamics. Eric Chaisson calculated an exponential increase of Free Energy Rate Density (FERD) in Cosmic Evolution, from the Big Bang until now, paralleling the increase of system's structure. We term these studies "Devology". We connect FERD to the principle of least action for complex systems, driving ...

  7. Analogies between urban hierarchies and river networks: Fractals, symmetry, and self-organized criticality

    International Nuclear Information System (INIS)

    Chen Yanguang

    2009-01-01

    A pair of nonlinear programming models is built to explain the fractal structure of systems of cities and those of rivers. The hierarchies of cities can be characterized by a set of exponential functions, which is identical in form to the Horton-Strahler's laws of the river networks. Four power laws can be derived from these exponential functions. The evolution of both systems of cities and rivers are then represented as nonlinear dual programming models: to maximize information entropy subject to a certain energy use or to minimize energy dissipation subject to certain information capacity. The optimal solutions of the programming problems are just the exponential equations associated with scaling relations. By doing so, fractals and the self-organized criticality marked by the power laws are interpreted using the idea from the entropy-maximization principle, which gives further weight to the suggestion that optimality of the system as a whole defines the dynamical origin of fractal forms in both nature and society.

  8. MACHINE LEARNING FOR THE SELF-ORGANIZATION OF DISTRIBUTED SYSTEMS IN ECONOMIC APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Jerzy Balicki

    2017-03-01

    Full Text Available In this paper, an application of machine learning to the problem of self-organization of distributed systems has been discussed with regard to economic applications, with particular emphasis on supervised neural network learning to predict stock investments and some ratings of companies. In addition, genetic programming can play an important role in the preparation and testing of several financial information systems. For this reason, machine learning applications have been discussed because some software applications can be automatically constructed by genetic programming. To obtain a competitive advantage, machine learning can be used for the management of self-organizing cloud computing systems performing calculations for business. Also the use of selected economic self-organizing distributed systems has been described, including some testing methods of predicting borrower reliability. Finally, some conclusions and directions for further research have been proposed.

  9. Self-organization in Complex Systems The Past, Present, and Future of Synergetics : International Symposium

    CERN Document Server

    Pelster, Axel

    2016-01-01

    This proceedings volume contains talks and poster presentations from the International Symposium "Self-Organization in Complex Systems: The Past, Present, and Future of Synergetics", which took place at Hanse-Wissenschaftskolleg, an Institute of Advanced Studies, in Delmenhorst, Germany, during the period November 13 - 16, 2012. The Symposium was organized in honour of Hermann Haken, who celebrated his 85th birthday in 2012. With his fundamental theory of Synergetics he had laid the mathematical-physical basis for describing and analyzing self-organization processes in a diversity of fields of research. The quest for common and universal principles of self-organization in complex systems was clearly covered by the wide range of interdisciplinary topics reported during the Symposium. These extended from complexity in classical systems and quantum systems over self-organisation in neuroscience even to the physics of finance. Moreover, by combining a historical view with a present status report the Symposium con...

  10. Expanding Evolutionary Theory beyond Darwinism with Elaborating, Self-Organizing, and Fractionating Complex Evolutionary Systems

    Science.gov (United States)

    Fichter, Lynn S.; Pyle, E. J.; Whitmeyer, S. J.

    2010-01-01

    Earth systems increase in complexity, diversity, and interconnectedness with time, driven by tectonic/solar energy that keeps the systems far from equilibrium. The evolution of Earth systems is facilitated by three evolutionary mechanisms: "elaboration," "fractionation," and "self-organization," that share…

  11. Mobility Model for Self-Organizing and Cooperative MSN and MANET Systems

    Directory of Open Access Journals (Sweden)

    Andrzej Sikora

    2012-03-01

    Full Text Available Self-organization mechanisms are used for building scalable systems consisting of a huge number of subsystems. In computer networks, self-organizing is especially important in ad hoc networking. A self-organizing ad hoc network is a collection of wireless devices that collaborate with each other to form a network system that adapts to achieve a goal or goals. Such network is often built from mobile devices that may spontaneously create a network and dynamically adapted to changes in an unknown environment. Mobility pattern is a critical element that influences the performance characteristics of mobile sensor networks (MSN and mobile ad hoc networks (MANET. In this paper, we survey main directions to mobility modeling. We describe a novel algorithm for calculating mobility patterns for mobile devices that is based on a cluster formation and an artificial potential function. Finally, we present the simulation results of its application to a rescue mission planning.

  12. Self-organization leads to supraoptimal performance in public transportation systems.

    Science.gov (United States)

    Gershenson, Carlos

    2011-01-01

    The performance of public transportation systems affects a large part of the population. Current theory assumes that passengers are served optimally when vehicles arrive at stations with regular intervals. In this paper, it is shown that self-organization can improve the performance of public transportation systems beyond the theoretical optimum by responding adaptively to local conditions. This is possible because of a "slower-is-faster" effect, where passengers wait more time at stations but total travel times are reduced. The proposed self-organizing method uses "antipheromones" to regulate headways, which are inspired by the stigmergy (communication via environment) of some ant colonies.

  13. Relation between the Hurst Exponent and the Efficiency of Self-organization of a Deformable System

    Science.gov (United States)

    Alfyorova, E. A.; Lychagin, D. V.

    2018-04-01

    We have established the degree of self-organization of a system under plastic deformation at different scale levels. Using fractal analysis, we have determined the Hurst exponent and correlation lengths in the region of formation of a corrugated (wrinkled) structure in [111] nickel single crystals under compression. This has made it possible to single out two (micro-and meso-) levels of self-organization in the deformable system. A qualitative relation between the values of the Hurst exponent and the stages of the stress-strain curve has been established.

  14. Physics of far-from-equilibrium systems and self-organization

    International Nuclear Information System (INIS)

    Nicolis, G.

    1993-01-01

    The status of self-organization phenomena from the stand point of the physical sciences are analyzed. Non linear dynamics and the presence of constraints maintaining the system far from equilibrium are shown to be the basic mechanism involved in the emergence of these phenomena. Some particularly representative experiments are first presented: thermal conversion, chemical reactions (Benard problem), biological systems, and their explanation through order, disorder, non-linearity, irreversibility, stability, bifurcation, symmetry breaking, etc., concepts. Then it is shown how the self-organization paradigm allows to model problems outside the traditional realm of the physical sciences. 29 figs., 27 refs

  15. Self-Organizing and Autonomous Learning Agents and Systems

    National Research Council Canada - National Science Library

    Shen, Wei-Min

    2004-01-01

    ...) Autonomous discovery and response to unexpected topology changes; (2) A new distributed functional language called DH2 for programming of self-reconfigurable systems using hormone-inspired computational methods...

  16. Self-organization of complex networks as a dynamical system.

    Science.gov (United States)

    Aoki, Takaaki; Yawata, Koichiro; Aoyagi, Toshio

    2015-01-01

    To understand the dynamics of real-world networks, we investigate a mathematical model of the interplay between the dynamics of random walkers on a weighted network and the link weights driven by a resource carried by the walkers. Our numerical studies reveal that, under suitable conditions, the co-evolving dynamics lead to the emergence of stationary power-law distributions of the resource and link weights, while the resource quantity at each node ceaselessly changes with time. We analyze the network organization as a deterministic dynamical system and find that the system exhibits multistability, with numerous fixed points, limit cycles, and chaotic states. The chaotic behavior of the system leads to the continual changes in the microscopic network dynamics in the absence of any external random noises. We conclude that the intrinsic interplay between the states of the nodes and network reformation constitutes a major factor in the vicissitudes of real-world networks.

  17. Self-organizing dynamic stability of far-from-equilibrium biological systems

    Science.gov (United States)

    Ivanitskii, G. R.

    2017-10-01

    One indication of the stability of a living system is the variation of the system’s characteristic time scales. Underlying the stability mechanism are the structural hierarchy and self-organization of systems, factors that give rise to a positive (accelerating) feedback and a negative (braking) feedback. Information processing in the brain cortex plays a special role in highly organized living organisms.

  18. Architecture for self-organizing, co-operative and robust building automation systems

    NARCIS (Netherlands)

    Bernier, F.; Ploennigs, J.; Pesch, D.; Lesecq, S.; Basten, T.; Boubekeur, M.; Denteneer, T.J.J.; Oltmanns, F.; Lehmann, M.; Mai, Linh Tuan; Mc Gibney, A.; Rea, S.; Pacull, F.; Guyon-Gardeux, C.; Ducreux, L.F.; Thior, S.; Hendriks, M.; Verriet, J.H.; Fedor, S.

    2013-01-01

    This paper provides an overview of the architecture for self-organizing, co-operative and robust Building Automation Systems (BAS) proposed by the EC funded FP7 SCUBA1 project. We describe the current situation in monitoring and control systems and outline the typical stakeholders involved in the

  19. Architecture for self-organizing, co-operative and robust Building Automation Systems

    NARCIS (Netherlands)

    Bernier, F.; Ploennigs, J.; Pesch, D.; Lesecq, S.; Basten, T.; Boubekeur, M.; Denteneer, D.; Oltmanns, F.; Bonnard, F.; Lehmann, M.; Mai, T.L.; McGibney, A.; Rea, S.; Pacull, F.; Guyon-Gardeux, C.; Ducreux, L.F.; Thior, S.; Hendriks, M.; Verriet, J.; Fedor, S.

    2013-01-01

    This paper provides an overview of the architecture for self-organizing, co-operative and robust Building Automation Systems (BAS) proposed by the EC funded FP7 SCUBA1 project. We describe the current situation in monitoring and control systems and outline the typical stakeholders involved in the

  20. An architecture for self-organization in pervasive systems

    NARCIS (Netherlands)

    Syed, Aly; Lukkien, J.J.; Frunza, Roxana

    2010-01-01

    Pervasive computing environments consist of many independent collaborating electronic devices, including sensors and actuators. Ad-Hoc extendibility of such systems is desirable but the current network technologies use the concept of a central coordinator device in the network or define application

  1. Computational Genetic Regulatory Networks Evolvable, Self-organizing Systems

    CERN Document Server

    Knabe, Johannes F

    2013-01-01

    Genetic Regulatory Networks (GRNs) in biological organisms are primary engines for cells to enact their engagements with environments, via incessant, continually active coupling. In differentiated multicellular organisms, tremendous complexity has arisen in the course of evolution of life on earth. Engineering and science have so far achieved no working system that can compare with this complexity, depth and scope of organization. Abstracting the dynamics of genetic regulatory control to a computational framework in which artificial GRNs in artificial simulated cells differentiate while connected in a changing topology, it is possible to apply Darwinian evolution in silico to study the capacity of such developmental/differentiated GRNs to evolve. In this volume an evolutionary GRN paradigm is investigated for its evolvability and robustness in models of biological clocks, in simple differentiated multicellularity, and in evolving artificial developing 'organisms' which grow and express an ontogeny starting fr...

  2. Population growth and environment as a self-organizing system

    Directory of Open Access Journals (Sweden)

    Peter M. Allen

    1999-01-01

    Full Text Available Over recent years a new understanding of complex systems, and their dynamics and evolution has emerged, and these have been shown to provide a new basis for models of the changing patterns of population and economic activities that shape the landscape. In this paper we make clear the necessarily partial description that any particular model must provide, and show the importance of a multidisciplinary, holistic understanding, linking any particular model to the co-evolution of its environment. In addition, we show how evolutionary processes link the microscopic level of molecules through successive scales of structure and organization ultimately to the biosphere itself, to issues of climatic change, of biomes at the continental scale and atmospheric and oceanic circulation patterns. Some very recent results will be shown which demonstrate that the world climate has already been modified considerably by human activities, particularly agriculture, underlining the vital need to understand better the on-going interaction between human activities and the biosphere.

  3. Self-organized criticality in a sheared granular stick-slip system

    International Nuclear Information System (INIS)

    Dalton, Fergal; Corcoran, David

    2001-01-01

    We present an analysis of results obtained from a mechanical apparatus consisting of an annular plate shearing over a granular bed. The size, energy dissipation, and duration of slips in the system exhibit power-law distributions and a 1/f 2 power spectrum, in accordance with self-organized criticality. We draw similarities with earthquakes

  4. Pattern formation and self-organization in a simple precipitation system

    NARCIS (Netherlands)

    Volford, Andras; Izsak, F.; Ripzam, Matyas; Lagzi, Istvan

    Various types of pattern formation and self-organization phenomena can be observed in biological, chemical, and geochemical systems due to the interaction of reaction with diffusion. The appearance of static precipitation patterns was reported first by Liesegang in 1896. Traveling waves and

  5. MACHINE LEARNING FOR THE SELF-ORGANIZATION OF DISTRIBUTED SYSTEMS IN ECONOMIC APPLICATIONS

    OpenAIRE

    Jerzy Balicki; Waldemar Korłub

    2017-01-01

    In this paper, an application of machine learning to the problem of self-organization of distributed systems has been discussed with regard to economic applications, with particular emphasis on supervised neural network learning to predict stock investments and some ratings of companies. In addition, genetic programming can play an important role in the preparation and testing of several financial information systems. For this reason, machine learning applications have been discussed because ...

  6. Self-organization principles result in robust control of flexible manufacturing systems

    DEFF Research Database (Denmark)

    Nature shows us in our daily life how robust, flexible and optimal self-organized modular constructions work in complex physical, chemical and biological systems, which successfully adapt to new and unexpected situations. A promising strategy is therefore to use such self-organization and pattern...... problems with several autonomous robots and several targets are considered as model of flexible manufacturing systems. Each manufacturing target has to be served in a given time interval by one and only one robot and the total working costs have to be minimized (or total winnings maximized). A specifically...... constructed dynamical system approach (coupled selection equations) is used which is based on pattern formation principles and results in fault resistant and robust behaviour. An important feature is that this type of control also guarantees feasiblitiy of the assignment solutions. In previous work...

  7. Information and Self-Organization A Macroscopic Approach to Complex Systems

    CERN Document Server

    Haken, Hermann

    2006-01-01

    This book presents the concepts needed to deal with self-organizing complex systems from a unifying point of view that uses macroscopic data. The various meanings of the concept "information" are discussed and a general formulation of the maximum information (entropy) principle is used. With the aid of results from synergetics, adequate objective constraints for a large class of self-organizing systems are formulated and examples are given from physics, life and computer science. The relationship to chaos theory is examined and it is further shown that, based on possibly scarce and noisy data, unbiased guesses about processes of complex systems can be made and the underlying deterministic and random forces determined. This allows for probabilistic predictions of processes, with applications to numerous fields in science, technology, medicine and economics. The extensions of the third edition are essentially devoted to an introduction to the meaning of information in the quantum context. Indeed, quantum inform...

  8. Hybrid Societies: Challenges and Perspectives in the Design of Collective Behavior in Self-organizing Systems

    Directory of Open Access Journals (Sweden)

    Heiko eHamann

    2016-04-01

    Full Text Available Hybrid societies are self-organizing, collective systems composed of different components, for example, natural and artificial parts (bio-hybrid or human beings interacting with and through technical systems (socio-technical. Many different disciplines investigate methods and systems closely related to the design of hybrid societies. A~stronger collaboration between these disciplines could allow for re-use of methods and create significant synergies. We identify three main areas of challenges in the design of self-organizing hybrid societies. First, we identify the formalization challenge. There is an urgent need for a generic model that allows a description and comparison of collective hybrid societies. Second, we identify the system design challenge. Starting from the formal specification of the system, we need to develop an integrated design process. Third, we identify the challenge of interdisciplinarity. Current research on self-organizing hybrid societies stretches over many different fields and hence requires the re-use and synthesis of methods at intersections between disciplines. We then conclude by presenting our perspective for future approaches with high potential in this area.

  9. Self-organizing plasmas

    International Nuclear Information System (INIS)

    Hayashi, T.; Sato, T.

    1999-01-01

    The primary purpose of this paper is to extract a grand view of self-organization through an extensive computer simulation of plasmas. The assertion is made that self-organization is governed by three key processes, i.e. the existence of an open complex system, the existence of information (energy) sources and the existence of entropy generation and expulsion processes. We find that self-organization takes place in an intermittent fashion when energy is supplied continuously from outside. In contrast, when the system state is suddenly changed into a non-equilibrium state externally, the system evolves stepwise and reaches a minimum energy state. We also find that the entropy production rate is maximized whenever a new ordered structure is created and that if the entropy generated during the self-organizing process is expelled from the system, then the self-organized structure becomes more prominent and clear. (author)

  10. Topological patterns in street networks of self-organized urban settlements

    Science.gov (United States)

    Buhl, J.; Gautrais, J.; Reeves, N.; Solé, R. V.; Valverde, S.; Kuntz, P.; Theraulaz, G.

    2006-02-01

    Many urban settlements result from a spatially distributed, decentralized building process. Here we analyze the topological patterns of organization of a large collection of such settlements using the approach of complex networks. The global efficiency (based on the inverse of shortest-path lengths), robustness to disconnections and cost (in terms of length) of these graphs is studied and their possible origins analyzed. A wide range of patterns is found, from tree-like settlements (highly vulnerable to random failures) to meshed urban patterns. The latter are shown to be more robust and efficient.

  11. Multidimensional Urban Sprawl in Europe: A Self-Organizing Map Approach

    NARCIS (Netherlands)

    Arribas-Bel, D.; Nijkamp, P.; Scholten, H.J.

    2011-01-01

    The present paper addresses the issue of urban sprawl in Europe from a multidimensional point of view, identifying the most sprawled areas and characterizing them in terms of population size. The literature is reviewed to categorize and extract the most relevant six dimensions that define the

  12. Improving Security for SCADA Sensor Networks with Reputation Systems and Self-Organizing Maps

    Directory of Open Access Journals (Sweden)

    Javier Blesa

    2009-11-01

    Full Text Available The reliable operation of modern infrastructures depends on computerized systems and Supervisory Control and Data Acquisition (SCADA systems, which are also based on the data obtained from sensor networks. The inherent limitations of the sensor devices make them extremely vulnerable to cyberwarfare/cyberterrorism attacks. In this paper, we propose a reputation system enhanced with distributed agents, based on unsupervised learning algorithms (self-organizing maps, in order to achieve fault tolerance and enhanced resistance to previously unknown attacks. This approach has been extensively simulated and compared with previous proposals.

  13. Self-Organizing Robots

    CERN Document Server

    Murata, Satoshi

    2012-01-01

    It is man’s ongoing hope that a machine could somehow adapt to its environment by reorganizing itself. This is what the notion of self-organizing robots is based on. The theme of this book is to examine the feasibility of creating such robots within the limitations of current mechanical engineering. The topics comprise the following aspects of such a pursuit: the philosophy of design of self-organizing mechanical systems; self-organization in biological systems; the history of self-organizing mechanical systems; a case study of a self-assembling/self-repairing system as an autonomous distributed system; a self-organizing robot that can create its own shape and robotic motion; implementation and instrumentation of self-organizing robots; and the future of self-organizing robots. All topics are illustrated with many up-to-date examples, including those from the authors’ own work. The book does not require advanced knowledge of mathematics to be understood, and will be of great benefit to students in the rob...

  14. Elements of automata theory and the theory of Markov chains. [Self-organizing control systems

    Energy Technology Data Exchange (ETDEWEB)

    Lind, M

    1975-03-01

    Selected topics from automata theory and the theory of Markov chains are treated. In particular, finite-memory automata are discussed in detail, and the results are used to formulate an automation model of a class of continuous systems. Stochastic automata are introduced as a natural generalization of the deterministic automaton. Markov chains are shown to be closely related to stochastic automata. Results from Markov chain theory are thereby directly applicable to analysis of stochastic automata. This report provides the theoretical foundation for the investigation in Riso Report No. 315 of a class of self-organizing control systems. (25 figures) (auth)

  15. Plate Tectonics as a Far-From-Equilibrium Self-Organized Dissipative System

    Science.gov (United States)

    Anderson, D. L.

    2001-12-01

    A fluid above the critical Rayleigh number is far from equilibrium and spontaneously organizes itself into patterns involving the collective motion of large numbers of molecules which are resisted by the viscosity of the fluid. No external template is involved in forming the pattern. In 1928 Pearson showed that Bénard's experiments were driven by variations in surface tension at the top of the fluid and the surface motions drove convection in the fluid. In this case, the surface organized itself AND the underlying fluid. Both internal buoyancy driven flow and flow driven by surface forces can be far-from-equilibrium self-organized open systems that receive energy and matter from the environment. In the Earth, the cold thermal boundary layer at the surface drives plate tectonics and introduces temperature, shear and pressure gradients into the mantle that drive mantle convection. The mantle provides energy and material but may not provide the template. Plate tectonics is therefore a candidate for a far-from-equilibrium dissipative self-organizing system. Alternatively, one could view mantle convection as the self-organized system and the plates as simply the surface manifestation. Lithospheric architecture also imposes lateral temperature gradients onto the mantle which can drive and organize flow. Far-from-equilibrium self-organization requires; an open system, interacting parts, nonlinearities or feedbacks, an outside steady source of energy or matter, multiple possible states and a source of dissipation. In uniform fluids viscosity is the source of dissipation. Sources of dissipation in the plate system include bending, breaking, folding, shearing, tearing, collision and basal drag. These can change rapidly, in contrast to plate driving forces, and introduce the sort of fluctuations that can reorganize far-from-equilibrium systems. Global plate reorganizations can alternatively be thought of as convective overturns of the mantle, or thermal weakening of plates

  16. Dynamical system with plastic self-organized velocity field as an alternative conceptual model of a cognitive system.

    Science.gov (United States)

    Janson, Natalia B; Marsden, Christopher J

    2017-12-05

    It is well known that architecturally the brain is a neural network, i.e. a collection of many relatively simple units coupled flexibly. However, it has been unclear how the possession of this architecture enables higher-level cognitive functions, which are unique to the brain. Here, we consider the brain from the viewpoint of dynamical systems theory and hypothesize that the unique feature of the brain, the self-organized plasticity of its architecture, could represent the means of enabling the self-organized plasticity of its velocity vector field. We propose that, conceptually, the principle of cognition could amount to the existence of appropriate rules governing self-organization of the velocity field of a dynamical system with an appropriate account of stimuli. To support this hypothesis, we propose a simple non-neuromorphic mathematical model with a plastic self-organized velocity field, which has no prototype in physical world. This system is shown to be capable of basic cognition, which is illustrated numerically and with musical data. Our conceptual model could provide an additional insight into the working principles of the brain. Moreover, hardware implementations of plastic velocity fields self-organizing according to various rules could pave the way to creating artificial intelligence of a novel type.

  17. On modeling complex interplay in small-scale self-organized socio-hydrological systems

    Science.gov (United States)

    Muneepeerakul, Rachata

    2017-04-01

    Successful and sustainable socio-hydrological systems, as in any coupled natural human-systems, require effective governance, which depends on the existence of proper infrastructure (both hard and soft). Recent work has addressed systems in which resource users and the organization responsible for maintaining the infrastructure are separate entities. However, many socio-hydrological systems, especially in developing countries, are small and without such formal division of labor; rather, such division of labor typically arises from self-organization within the population. In this work, we modify and mathematically operationalize a conceptual framework by developing a system of differential equations that capture the strategic behavior within such a self-organized population, its interplay with infrastructure characteristics and hydrological dynamics, and feedbacks between these elements. The model yields a number of insightful conditions related to long-term sustainability and collapse of the socio-hydrological system in the form of relationships between biophysical and social factors. These relationships encapsulate nonlinear interactions of these factors. The modeling framework is grounded in a solid conceptual foundation upon which additional modifications and realism can be built for potential reconciliation between socio-hydrology with other related fields and further applications.

  18. Firm Size, a Self-Organized Critical Phenomenon: Evidence from the Dynamical Systems Theory

    Science.gov (United States)

    Chandra, Akhilesh

    This research draws upon a recent innovation in the dynamical systems literature called the theory of self -organized criticality (SOC) (Bak, Tang, and Wiesenfeld 1988) to develop a computational model of a firm's size by relating its internal and the external sub-systems. As a holistic paradigm, the theory of SOC implies that a firm as a composite system of many degrees of freedom naturally evolves to a critical state in which a minor event starts a chain reaction that can affect either a part or the system as a whole. Thus, the global features of a firm cannot be understood by analyzing its individual parts separately. The causal framework builds upon a constant capital resource to support a volume of production at the existing level of efficiency. The critical size is defined as the production level at which the average product of a firm's factors of production attains its maximum value. The non -linearity is inferred by a change in the nature of relations at the border of criticality, between size and the two performance variables, viz., the operating efficiency and the financial efficiency. The effect of breaching the critical size is examined on the stock price reactions. Consistent with the theory of SOC, it is hypothesized that the temporal response of a firm breaching the level of critical size should behave as a flicker noise (1/f) process. The flicker noise is characterized by correlations extended over a wide range of time scales, indicating some sort of cooperative effect among a firm's degrees of freedom. It is further hypothesized that a firm's size evolves to a spatial structure with scale-invariant, self-similar (fractal) properties. The system is said to be self-organized inasmuch as it naturally evolves to the state of criticality without any detailed specifications of the initial conditions. In this respect, the critical state is an attractor of the firm's dynamics. Another set of hypotheses examines the relations between the size and the

  19. Heterogeneity and Self-Organization of Complex Systems Through an Application to Financial Market with Multiagent Systems

    Science.gov (United States)

    Lucas, Iris; Cotsaftis, Michel; Bertelle, Cyrille

    2017-12-01

    Multiagent systems (MAS) provide a useful tool for exploring the complex dynamics and behavior of financial markets and now MAS approach has been widely implemented and documented in the empirical literature. This paper introduces the implementation of an innovative multi-scale mathematical model for a computational agent-based financial market. The paper develops a method to quantify the degree of self-organization which emerges in the system and shows that the capacity of self-organization is maximized when the agent behaviors are heterogeneous. Numerical results are presented and analyzed, showing how the global market behavior emerges from specific individual behavior interactions.

  20. The Ramifications of Meddling with Systems Governed by Self-organized Critical Dynamics

    Science.gov (United States)

    Carreras, B. A.; Newman, D. E.; Dobson, I.

    2002-12-01

    Complex natural, well as man-made, systems often exhibit characteristics similar to those seen in self-organized critical (SOC) systems. The concept of self-organized criticality brings together ideas of self-organization of nonlinear dynamical systems with the often-observed near critical behavior of many natural phenomena. These phenomena exhibit self-similarities over extended ranges of spatial and temporal scales. In those systems, scale lengths may be described by fractal geometry and time scales that lead to 1/f-like power spectra. Natural applications include modeling the motion of tectonics plates, forest fires, magnetospheric dynamics, spin glass systems, and turbulent transport. In man-made systems, applications have included traffic dynamics, power and communications networks, and financial markets among many others. Simple cellular automata models such as the running sandpile model have been very useful in reproducing the complexity and characteristics of these systems. One characteristic property of the SOC systems is that they relax through what we call events. These events can happen over all scales of the system. Examples of these events are: earthquakes in the case of plate tectonic; fires in forest evolution extinction in the co evolution of biological species; and blackouts in power transmission systems. In a time-averaged sense, these systems are subcritical (that is, they lie in an average state that should not trigger any events) and the relaxation events happen intermittently. The time spent in a subcritical state relative to the time of the events varies from one system to another. For instance, the chance of finding a forest on fire is very low with the frequency of fires being on the order of one fire every few years and with many of these fires small and inconsequential. Very large fires happen over time periods of decades or even centuries. However, because of their consequences, these large but infrequent events are the important ones

  1. Relaxation and self-organization in two-dimensional plasma and neutral fluid flow systems

    International Nuclear Information System (INIS)

    Das, Amita

    2008-01-01

    Extensive numerical studies in the framework of a simplified two-dimensional model for neutral and plasma fluid for a variety of initial configurations and for both decaying and driven cases are carried out to illustrate relaxation toward a self-organized state. The dynamical model equation constitutes a simple choice for this purpose, e.g., the vorticity equation of the Navier-Stokes dynamics for the incompressible neutral fluids and the Hasegawa-Mima equation for plasma fluid flow system. Scatter plots are employed to observe a development of functional relationship, if any, amidst the generalized vorticity and its Laplacian. It is seen that they do not satisfy a linear relationship as the well known variational approach of enstrophy minimization subject to constancy of the energy integral for the two-dimensional (2D) system suggests. The observed nonlinear functional relationship is understood by separating the contribution to the scatter plot from spatial regions with intense vorticity patches and those of the background flow region where the background vorticity is weak or absent altogether. It is shown that such a separation has close connection with the known exact analytical solutions of the system. The analytical solutions are typically obtained by assuming a finite source of vorticity for the inner core of the localized structure, which is then matched with the solution in the outer region where vorticity is chosen to be zero. The work also demonstrates that the seemingly ad hoc choice of the linear vorticity source function for the inner region is in fact consistent with the self-organization paradigm of the 2D systems

  2. Improving public transportation systems with self-organization: A headway-based model and regulation of passenger alighting and boarding.

    Science.gov (United States)

    Carreón, Gustavo; Gershenson, Carlos; Pineda, Luis A

    2017-01-01

    The equal headway instability-the fact that a configuration with regular time intervals between vehicles tends to be volatile-is a common regulation problem in public transportation systems. An unsatisfactory regulation results in low efficiency and possible collapses of the service. Computational simulations have shown that self-organizing methods can regulate the headway adaptively beyond the theoretical optimum. In this work, we develop a computer simulation for metro systems fed with real data from the Mexico City Metro to test the current regulatory method with a novel self-organizing approach. The current model considers overall system's data such as minimum and maximum waiting times at stations, while the self-organizing method regulates the headway in a decentralized manner using local information such as the passenger's inflow and the positions of neighboring trains. The simulation shows that the self-organizing method improves the performance over the current one as it adapts to environmental changes at the timescale they occur. The correlation between the simulation of the current model and empirical observations carried out in the Mexico City Metro provides a base to calculate the expected performance of the self-organizing method in case it is implemented in the real system. We also performed a pilot study at the Balderas station to regulate the alighting and boarding of passengers through guide signs on platforms. The analysis of empirical data shows a delay reduction of the waiting time of trains at stations. Finally, we provide recommendations to improve public transportation systems.

  3. Cinematic Operation of the Cerebral Cortex Interpreted via Critical Transitions in Self-Organized Dynamic Systems.

    Science.gov (United States)

    Kozma, Robert; Freeman, Walter J

    2017-01-01

    Measurements of local field potentials over the cortical surface and the scalp of animals and human subjects reveal intermittent bursts of beta and gamma oscillations. During the bursts, narrow-band metastable amplitude modulation (AM) patters emerge for a fraction of a second and ultimately dissolve to the broad-band random background activity. The burst process depends on previously learnt conditioned stimuli (CS), thus different AM patterns may emerge in response to different CS. This observation leads to our cinematic theory of cognition when perception happens in discrete steps manifested in the sequence of AM patterns. Our article summarizes findings in the past decades on experimental evidence of cinematic theory of cognition and relevant mathematical models. We treat cortices as dissipative systems that self-organize themselves near a critical level of activity that is a non-equilibrium metastable state. Criticality is arguably a key aspect of brains in their rapid adaptation, reconfiguration, high storage capacity, and sensitive response to external stimuli. Self-organized criticality (SOC) became an important concept to describe neural systems. We argue that transitions from one AM pattern to the other require the concept of phase transitions, extending beyond the dynamics described by SOC. We employ random graph theory (RGT) and percolation dynamics as fundamental mathematical approaches to model fluctuations in the cortical tissue. Our results indicate that perceptions are formed through a phase transition from a disorganized (high entropy) to a well-organized (low entropy) state, which explains the swiftness of the emergence of the perceptual experience in response to learned stimuli.

  4. Methodical approaches to providing sustainable development of the transport industry management system based on self-organization

    Science.gov (United States)

    Belyantseva, Oksana; Panenkov, Andrey; Safonova, Nataliya

    2017-10-01

    Current conditions of the cognitive economy formation demand to take into account the leading role of information, knowledge and human capital in the development of the transport industry management system. The article substantiates the conceptual approach to the self-organization of a management system on the basis of innovative changes. Human capital is the key aspect of self-organization, so the directions of improving the workforce quality are justified. Basing on the information-innovative genesis of the process of self-organization, the authors justified the necessity of preventing asymmetric information. For this pupose the actions against the resistance to innovations were proposed. The implementation of certain measures contributes to the effective development of the transport management system.

  5. Self-organized crystallization mechanism of non-equilibrium 2:1 type phyllosilicate systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The crystallization mechanism of 2:1 type regular interstratified minerals is investigated in views of non-equilibrium thermodynamics. The structural chemistry of relative layers and their interstratified combinations is analyzed and six kinds of non-equilibrium chemical systems have been induced. The universal laws of chemical reactions which happened in the interface region of these non-equilibrium systems have been summarized. From these laws, two reaction systems crystallizing out Tosudite and Rectorite respectively have been recovered. The kinetic model of chemical reactions has been developed by means of the mass conservation law. The oscillatory solution showing regular interstratified features has also been obtained numerically. These results indicate that the difference in original chemical composition among systems can affect the chemical connotation of reactants, intermediate products and resultants, and the flow chart of chemical reaction, but cannot change their crystallization behavior of network-forming cations, bigger and smaller network-modifying cations during crystallization. Hence, their kinetic model reflecting the universal crystallization law of these cations is just the same. These systems will crystallize out regular interstratified minerals at suitable parameters, which always exist as domain with nanometer-sized in thickness and can be called the self-organized ordering structure.

  6. A Self-Organizing Spatial Clustering Approach to Support Large-Scale Network RTK Systems.

    Science.gov (United States)

    Shen, Lili; Guo, Jiming; Wang, Lei

    2018-06-06

    The network real-time kinematic (RTK) technique can provide centimeter-level real time positioning solutions and play a key role in geo-spatial infrastructure. With ever-increasing popularity, network RTK systems will face issues in the support of large numbers of concurrent users. In the past, high-precision positioning services were oriented towards professionals and only supported a few concurrent users. Currently, precise positioning provides a spatial foundation for artificial intelligence (AI), and countless smart devices (autonomous cars, unmanned aerial-vehicles (UAVs), robotic equipment, etc.) require precise positioning services. Therefore, the development of approaches to support large-scale network RTK systems is urgent. In this study, we proposed a self-organizing spatial clustering (SOSC) approach which automatically clusters online users to reduce the computational load on the network RTK system server side. The experimental results indicate that both the SOSC algorithm and the grid algorithm can reduce the computational load efficiently, while the SOSC algorithm gives a more elastic and adaptive clustering solution with different datasets. The SOSC algorithm determines the cluster number and the mean distance to cluster center (MDTCC) according to the data set, while the grid approaches are all predefined. The side-effects of clustering algorithms on the user side are analyzed with real global navigation satellite system (GNSS) data sets. The experimental results indicate that 10 km can be safely used as the cluster radius threshold for the SOSC algorithm without significantly reducing the positioning precision and reliability on the user side.

  7. Modeling Physical Processes at the Nanoscale—Insight into Self-Organization of Small Systems (abstract)

    Science.gov (United States)

    Proykova, Ana

    2009-04-01

    Essential contributions have been made in the field of finite-size systems of ingredients interacting with potentials of various ranges. Theoretical simulations have revealed peculiar size effects on stability, ground state structure, phases, and phase transformation of systems confined in space and time. Models developed in the field of pure physics (atomic and molecular clusters) have been extended and successfully transferred to finite-size systems that seem very different—small-scale financial markets, autoimmune reactions, and social group reactions to advertisements. The models show that small-scale markets diverge unexpectedly fast as a result of small fluctuations; autoimmune reactions are sequences of two discontinuous phase transitions; and social groups possess critical behavior (social percolation) under the influence of an external field (advertisement). Some predicted size-dependent properties have been experimentally observed. These findings lead to the hypothesis that restrictions on an object's size determine the object's total internal (configuration) and external (environmental) interactions. Since phases are emergent phenomena produced by self-organization of a large number of particles, the occurrence of a phase in a system containing a small number of ingredients is remarkable.

  8. Molecular System Dynamics for Self-Organization in Heterogeneous Wireless Networks

    Directory of Open Access Journals (Sweden)

    Milner StuartD

    2010-01-01

    Full Text Available We have been looking at the properties of physical configurations that occur in nature in order to characterize, predict, and control network robustness in dynamic communication networks. Our framework is based on the definition of a potential energy function to characterize robustness in communication networks and the study of first- and second-order variations of the potential energy to provide prediction and control strategies for network-performance optimization. This paper describes novel investigations within this framework that draw from molecular system dynamics. The Morse potential, which governs the energy stored in bonds within molecules, is considered for the characterization of the potential energy of communication links in the presence of physical constraints such as the power available at the transmitters in a network. The inclusion of the Morse potential translates into improved control strategies, where forces on network nodes drive the release, retention, or reconfiguration of communication links based on their role within the network architecture. The performance of the proposed approach is measured in terms of the number of source-to-destination connections that have an end-to-end communications path. Simulation results show the effectiveness of our control mechanism, where the physical topology reorganizes to maximize the number of source-to-destination communicating pairs. The algorithms developed are completely distributed, show constant time complexity and produce optimal solutions from local interactions, thus preserving the system's self-organizing capability.

  9. Self-organized magnetic particles to tune the mechanical behavior of a granular system

    Science.gov (United States)

    Cox, Meredith; Wang, Dong; Barés, Jonathan; Behringer, Robert P.

    2016-09-01

    Above a certain density a granular material jams. This property can be controlled by either tuning a global property, such as the packing fraction or by applying shear strain, or at the micro-scale by tuning grain shape, inter-particle friction or externally controlled organization. Here, we introduce a novel way to change a local granular property by adding a weak anisotropic magnetic interaction between particles. We measure the evolution of the pressure, P, and coordination number, Z, for a packing of 2D photo-elastic disks, subject to uniaxial compression. A fraction R m of the particles have embedded cuboidal magnets. The strength of the magnetic interactions between particles is too weak to have a strong direct effect on P or Z when the system is jammed. However, the magnetic interactions play an important role in the evolution of latent force networks when systems containing a large enough fraction of the particles with magnets are driven through unjammed to jammed states. In this case, a statistically stable network of magnetic chains self-organizes before jamming and overlaps with force chains once jamming occurs, strengthening the granular medium. This property opens a novel way to control mechanical properties of granular materials.

  10. Self-organizing Systems in the Light of the Arrows of Orderedness, Symmetry, and Entropy

    Directory of Open Access Journals (Sweden)

    György Darvas

    2008-07-01

    Full Text Available The paper makes an attempt to resolve two conceptual mingling: (a the mingling of the two interpretations of the concept of orderedness applied in statistical thermodynamics and in symmetrology, and (b the mingling of two interpretations of evolution applied in global and local processes. In conclusion, it formulates a new interpretation on the relation of the emergence of new material qualities in selforganizing processes on the one hand, and the evolution of the universe, on the other. The process of evolution is a sequence of emergence of new material qualities by self-organization processes, which happen in negligible small segments of the universe. Although thermodynamics looks at the universe as a closed (isolated system, this holds for its outside boundaries only, while the universe has many subsystems inside, which are not isolated (closed, since they are in a permanent exchange of matter, energy, etc. with their environment (with the rest of the universe through their open boundaries. Any ";;emergence";; takes place, i.e., all new qualities come into being just in these small open segments of the universe. The conditions to apply the second law of thermodynamics are not present here. Therefore, global evolution of the universe is the consequence of local symmetry decreases, local decreases of orderedness, and possible local decreases of entropy.

  11. Self organized criticality

    International Nuclear Information System (INIS)

    Creutz, M.

    1993-03-01

    Self organized criticality refers to the tendency of highly dissipative systems to drive themselves to a critical state. This has been proposed to explain why observed physics often displays a wide disparity of length and time scales. The phenomenon can be studied in simple cellular automaton models

  12. A Self-Organizing Spatial Clustering Approach to Support Large-Scale Network RTK Systems

    Directory of Open Access Journals (Sweden)

    Lili Shen

    2018-06-01

    Full Text Available The network real-time kinematic (RTK technique can provide centimeter-level real time positioning solutions and play a key role in geo-spatial infrastructure. With ever-increasing popularity, network RTK systems will face issues in the support of large numbers of concurrent users. In the past, high-precision positioning services were oriented towards professionals and only supported a few concurrent users. Currently, precise positioning provides a spatial foundation for artificial intelligence (AI, and countless smart devices (autonomous cars, unmanned aerial-vehicles (UAVs, robotic equipment, etc. require precise positioning services. Therefore, the development of approaches to support large-scale network RTK systems is urgent. In this study, we proposed a self-organizing spatial clustering (SOSC approach which automatically clusters online users to reduce the computational load on the network RTK system server side. The experimental results indicate that both the SOSC algorithm and the grid algorithm can reduce the computational load efficiently, while the SOSC algorithm gives a more elastic and adaptive clustering solution with different datasets. The SOSC algorithm determines the cluster number and the mean distance to cluster center (MDTCC according to the data set, while the grid approaches are all predefined. The side-effects of clustering algorithms on the user side are analyzed with real global navigation satellite system (GNSS data sets. The experimental results indicate that 10 km can be safely used as the cluster radius threshold for the SOSC algorithm without significantly reducing the positioning precision and reliability on the user side.

  13. A learning heuristic for space mapping and searching self-organizing systems using adaptive mesh refinement

    Science.gov (United States)

    Phillips, Carolyn L.

    2014-09-01

    In a complex self-organizing system, small changes in the interactions between the system's components can result in different emergent macrostructures or macrobehavior. In chemical engineering and material science, such spontaneously self-assembling systems, using polymers, nanoscale or colloidal-scale particles, DNA, or other precursors, are an attractive way to create materials that are precisely engineered at a fine scale. Changes to the interactions can often be described by a set of parameters. Different contiguous regions in this parameter space correspond to different ordered states. Since these ordered states are emergent, often experiment, not analysis, is necessary to create a diagram of ordered states over the parameter space. By issuing queries to points in the parameter space (e.g., performing a computational or physical experiment), ordered states can be discovered and mapped. Queries can be costly in terms of resources or time, however. In general, one would like to learn the most information using the fewest queries. Here we introduce a learning heuristic for issuing queries to map and search a two-dimensional parameter space. Using a method inspired by adaptive mesh refinement, the heuristic iteratively issues batches of queries to be executed in parallel based on past information. By adjusting the search criteria, different types of searches (for example, a uniform search, exploring boundaries, sampling all regions equally) can be flexibly implemented. We show that this method will densely search the space, while preferentially targeting certain features. Using numerical examples, including a study simulating the self-assembly of complex crystals, we show how this heuristic can discover new regions and map boundaries more accurately than a uniformly distributed set of queries.

  14. Feature-based alert correlation in security systems using self organizing maps

    Science.gov (United States)

    Kumar, Munesh; Siddique, Shoaib; Noor, Humera

    2009-04-01

    The security of the networks has been an important concern for any organization. This is especially important for the defense sector as to get unauthorized access to the sensitive information of an organization has been the prime desire for cyber criminals. Many network security techniques like Firewall, VPN Concentrator etc. are deployed at the perimeter of network to deal with attack(s) that occur(s) from exterior of network. But any vulnerability that causes to penetrate the network's perimeter of defense, can exploit the entire network. To deal with such vulnerabilities a system has been evolved with the purpose of generating an alert for any malicious activity triggered against the network and its resources, termed as Intrusion Detection System (IDS). The traditional IDS have still some deficiencies like generating large number of alerts, containing both true and false one etc. By automatically classifying (correlating) various alerts, the high-level analysis of the security status of network can be identified and the job of network security administrator becomes much easier. In this paper we propose to utilize Self Organizing Maps (SOM); an Artificial Neural Network for correlating large amount of logged intrusion alerts based on generic features such as Source/Destination IP Addresses, Port No, Signature ID etc. The different ways in which alerts can be correlated by Artificial Intelligence techniques are also discussed. . We've shown that the strategy described in the paper improves the efficiency of IDS by better correlating the alerts, leading to reduced false positives and increased competence of network administrator.

  15. Life and Understanding: The Origins of "Understanding" in Self-Organizing Nervous Systems.

    Science.gov (United States)

    Yufik, Yan M; Friston, Karl

    2016-01-01

    This article is motivated by a formulation of biotic self-organization in Friston (2013), where the emergence of "life" in coupled material entities (e.g., macromolecules) was predicated on bounded subsets that maintain a degree of statistical independence from the rest of the network. Boundary elements in such systems constitute a Markov blanket ; separating the internal states of a system from its surrounding states. In this article, we ask whether Markov blankets operate in the nervous system and underlie the development of intelligence, enabling a progression from the ability to sense the environment to the ability to understand it. Markov blankets have been previously hypothesized to form in neuronal networks as a result of phase transitions that cause network subsets to fold into bounded assemblies, or packets (Yufik and Sheridan, 1997; Yufik, 1998a). The ensuing neuronal packets hypothesis builds on the notion of neuronal assemblies (Hebb, 1949, 1980), treating such assemblies as flexible but stable biophysical structures capable of withstanding entropic erosion. In other words, structures that maintain their integrity under changing conditions. In this treatment, neuronal packets give rise to perception of "objects"; i.e., quasi-stable (stimulus bound) feature groupings that are conserved over multiple presentations (e.g., the experience of perceiving "apple" can be interrupted and resumed many times). Monitoring the variations in such groups enables the apprehension of behavior; i.e., attributing to objects the ability to undergo changes without loss of self-identity. Ultimately, "understanding" involves self-directed composition and manipulation of the ensuing "mental models" that are constituted by neuronal packets, whose dynamics capture relationships among objects: that is, dependencies in the behavior of objects under varying conditions. For example, movement is known to involve rotation of population vectors in the motor cortex (Georgopoulos et al

  16. Spatial self-organization in a multi-strain host–pathogen system

    International Nuclear Information System (INIS)

    Liu, Quan-Xing; Van de Koppel, Johan; Wang, Rong-Hua; Jin, Zhen; Alonso, David

    2010-01-01

    We develop stochastic spatial epidemic models with the competition of two pathogenic strains. The dynamics resulting from different approaches are examined using both non-spatial and spatially explicit models. Our results show that pair approximation, well-mixed ordinary differential equations (ODEs), Gillespie-algorithm-based simulations and spatially explicit models give similar qualitative results. In particular, the temporal evolution of the spatial model can be successfully approximated by pair equations. Simulation results obtained from the spatially explicit model show that, first, mutation plays a major role in multi-strain coexistence, second, mild virulence remarkably decreases the coexistence domain of the parameter space and, third, large-scale self-organized spatial patterns emerge for a wide range of transmission and virulence parameter values, where spatial self-organized clusters reveal a power law behavior within the coexistence domain

  17. Gaia eclipsing binary and multiple systems. Supervised classification and self-organizing maps

    Science.gov (United States)

    Süveges, M.; Barblan, F.; Lecoeur-Taïbi, I.; Prša, A.; Holl, B.; Eyer, L.; Kochoska, A.; Mowlavi, N.; Rimoldini, L.

    2017-07-01

    Context. Large surveys producing tera- and petabyte-scale databases require machine-learning and knowledge discovery methods to deal with the overwhelming quantity of data and the difficulties of extracting concise, meaningful information with reliable assessment of its uncertainty. This study investigates the potential of a few machine-learning methods for the automated analysis of eclipsing binaries in the data of such surveys. Aims: We aim to aid the extraction of samples of eclipsing binaries from such databases and to provide basic information about the objects. We intend to estimate class labels according to two different, well-known classification systems, one based on the light curve morphology (EA/EB/EW classes) and the other based on the physical characteristics of the binary system (system morphology classes; detached through overcontact systems). Furthermore, we explore low-dimensional surfaces along which the light curves of eclipsing binaries are concentrated, and consider their use in the characterization of the binary systems and in the exploration of biases of the full unknown Gaia data with respect to the training sets. Methods: We have explored the performance of principal component analysis (PCA), linear discriminant analysis (LDA), Random Forest classification and self-organizing maps (SOM) for the above aims. We pre-processed the photometric time series by combining a double Gaussian profile fit and a constrained smoothing spline, in order to de-noise and interpolate the observed light curves. We achieved further denoising, and selected the most important variability elements from the light curves using PCA. Supervised classification was performed using Random Forest and LDA based on the PC decomposition, while SOM gives a continuous 2-dimensional manifold of the light curves arranged by a few important features. We estimated the uncertainty of the supervised methods due to the specific finite training set using ensembles of models constructed

  18. Urban Trauma and Self-organization of the City. Autopoiesis in the Battle of Mogadishu and the Siege of Sarajevo

    OpenAIRE

    Aquilué, Ines; Lekovic, Milica; Ruiz Sánchez, Javier

    2016-01-01

    IntroductionCities under armed conflict become urban laboratories. Changes of their urban structure reflect intrinsic properties of the city, hardly noticeable in circumstances of stability. Not only does a conflict-conditioned urban trauma imply shattered spatial and social networks, it also removes memory from space, jeopardizing both city´s history and future. However, viewed through the lens of complexity, “trauma is an element that is not external, but intrinsically constitutive of a cit...

  19. Intelligent system for statistically significant expertise knowledge on the basis of the model of self-organizing nonequilibrium dissipative system

    Directory of Open Access Journals (Sweden)

    E. A. Tatokchin

    2017-01-01

    Full Text Available Development of the modern educational technologies caused by broad introduction of comput-er testing and development of distant forms of education does necessary revision of methods of an examination of pupils. In work it was shown, need transition to mathematical criteria, exami-nations of knowledge which are deprived of subjectivity. In article the review of the problems arising at realization of this task and are offered approaches for its decision. The greatest atten-tion is paid to discussion of a problem of objective transformation of rated estimates of the ex-pert on to the scale estimates of the student. In general, the discussion this question is was con-cluded that the solution to this problem lies in the creation of specialized intellectual systems. The basis for constructing intelligent system laid the mathematical model of self-organizing nonequilibrium dissipative system, which is a group of students. This article assumes that the dissipative system is provided by the constant influx of new test items of the expert and non-equilibrium – individual psychological characteristics of students in the group. As a result, the system must self-organize themselves into stable patterns. This patern will allow for, relying on large amounts of data, get a statistically significant assessment of student. To justify the pro-posed approach in the work presents the data of the statistical analysis of the results of testing a large sample of students (> 90. Conclusions from this statistical analysis allowed to develop intelligent system statistically significant examination of student performance. It is based on data clustering algorithm (k-mean for the three key parameters. It is shown that this approach allows you to create of the dynamics and objective expertise evaluation.

  20. Patterns identification in supervisory systems of nuclear reactors installations and gas pipelines systems using self-organizing maps

    International Nuclear Information System (INIS)

    Doraskevicius Junior, Waldemar

    2005-01-01

    Self-Organizing Maps, SOM, of Kohonen were studied, implemented and tested with the aim of developing, for the energy branch, an effective tool especially for transient identification in nuclear reactors and for gas pipelines networks logistic supervision, by classifying operations and identifying transients or abnormalities. The digital system for the test was developed in Java platform, for the portability and scalability, and for belonging to free development platforms. The system, executed in personal computers, showed satisfactory results to aid in decision taking, by classifying IRIS (International Reactor Innovative and Secure) reactor operation conditions (data from simulator) and by classifying Southeast (owner: TRANSPETRO - Brazil) gas pipeline network. Various adaptations were needed for such business, as new topologies for the output layer of artificial neural network and particular preparation for the input data. (author)

  1. The self-organization and functional activity of binary system based on erucyl amidopropyl betaine - alkylated polyethyleneimine

    Science.gov (United States)

    Gaynanova, Gulnara A.; Valiakhmetova, Alsu R.; Kuryashov, Dmitry A.; Kudryashova, Yuliana R.; Lukashenko, Svetlana S.; Syakaev, Victor V.; Latypov, Shamil K.; Bukharov, Sergey V.; Bashkirtseva, Natalia Yu.; Zakharova, Lucia Ya.

    2013-11-01

    The self-organization in individual and binary aqueous solutions of a zwitterionic surfactant erucyl amidopropyl betaine and alkylated polyethyleneimine is carried out with a wide range of physical and chemical methods, including tensiometry, conductometry, dynamic light scattering, pH-metry, spectrophotometry, and fluorescence spectroscopy. The data obtained strongly support the formation of nanosized aggregates in the systems and provide information on their structure and probable morphological transitions. High solubilization capacity and data on the contact angle showed a possibility of the application of these systems as nanocontainers or oil wetting agents in the oil recovery.

  2. New epistemological foundations for cultural psychology: from an atomistic to a self-organizing view of living systems.

    Science.gov (United States)

    De Pascale, Adele

    2014-01-01

    An epistemological foundation for cultural psychology is essential to neuro- and behavioural sciences for the challenge psychological sciences must currently face: searching for an explanation of how a brain can become a mind and how individuals assign a sense to the world and their life. Biological systems are very likely determined by physical and chemical laws of spontaneous self-organization and endogenous constraints but, even if the major result of the Darwinian revolution is "the discovery that living species are their story", the modern synthesis of the evolution theory adopted only continuist and gradualist hypotheses. This nourished the analogy between the theory of natural selection and the theory of operant conditioning, thereby supporting empiricist associationism and the methodological positivism of behavioural and "classical" cognitive psychologists. Current scientific contributions provide evidence to the need for psychotherapy and psychopathology of a new epistemological approach in order to connect research stemming from animal models, up to the most abstract levels of personal meaning. The complex system oriented approach, here described, called "post-rationalism", shaped by a change initiated by evolutionary epistemology. The regulation of emotions initially develops within interpersonal relationships and evolves during both phylogeny and ontogeny, according to complex self-organization processes, leading to the acquisition of Self-organizing abilities and the construction of personal meaning. Endorsing the epistemological similarities of neo-Darwinism and behaviourism, and differentiating from this, the above mentioned approach, emphasises the fact that clinical and psycho-therapeutical practice must be founded on the laws of biological organisation: the ongoing activity of neurobiological systems, including the more abstract domains of thought and language.

  3. New epistemological foundations for cultural psychology: from an atomistic to a self-organizing view of living systems

    Directory of Open Access Journals (Sweden)

    Adele De Pascale

    2014-09-01

    Full Text Available An epistemological foundation for cultural psychology is essential to neuro- and behavioural sciences for the challenge psychological sciences must currently face: searching for an explanation of how a brain can become a mind and how individuals assign a sense to the world and their life. Biological systems are very likely determined by physical and chemical laws of spontaneous self-organization and endogenous constraints but, even if the major result of the Darwinian revolution is "the discovery that living species are their story", the modern synthesis of the evolution theory adopted only continuist and gradualist hypotheses. This nourished the analogy between the theory of natural selection and the theory of operant conditioning, thereby supporting empiricist associationism and the methodological positivism of behavioural and "classical" cognitive psychologists. Current scientific contributions provide evidence to the need for psychotherapy and psychopathology of a new epistemological approach in order to connect research stemming from animal models, up to the most abstract levels of personal meaning. The complex system oriented approach, here described, called "post-rationalism", shaped by a change initiated by evolutionary epistemology. The regulation of emotions initially develops within interpersonal relationships and evolves during both phylogeny and ontogeny, according to complex self-organization processes, leading to the acquisition of Self-organizing abilities and the construction of personal meaning. Endorsing the epistemological similarities of neo-Darwinism and behaviourism, and differentiating from this, the above mentioned approach, emphasises the fact that clinical and psycho-therapeutical practice must be founded on the laws of biological organisation: the ongoing activity of neurobiological systems, including the more abstract domains of thought and language.

  4. Stochastic Oscillation in Self-Organized Critical States of Small Systems: Sensitive Resting State in Neural Systems.

    Science.gov (United States)

    Wang, Sheng-Jun; Ouyang, Guang; Guang, Jing; Zhang, Mingsha; Wong, K Y Michael; Zhou, Changsong

    2016-01-08

    Self-organized critical states (SOCs) and stochastic oscillations (SOs) are simultaneously observed in neural systems, which appears to be theoretically contradictory since SOCs are characterized by scale-free avalanche sizes but oscillations indicate typical scales. Here, we show that SOs can emerge in SOCs of small size systems due to temporal correlation between large avalanches at the finite-size cutoff, resulting from the accumulation-release process in SOCs. In contrast, the critical branching process without accumulation-release dynamics cannot exhibit oscillations. The reconciliation of SOCs and SOs is demonstrated both in the sandpile model and robustly in biologically plausible neuronal networks. The oscillations can be suppressed if external inputs eliminate the prominent slow accumulation process, providing a potential explanation of the widely studied Berger effect or event-related desynchronization in neural response. The features of neural oscillations and suppression are confirmed during task processing in monkey eye-movement experiments. Our results suggest that finite-size, columnar neural circuits may play an important role in generating neural oscillations around the critical states, potentially enabling functional advantages of both SOCs and oscillations for sensitive response to transient stimuli.

  5. Self-organized Learning Environments

    DEFF Research Database (Denmark)

    Dalsgaard, Christian; Mathiasen, Helle

    2007-01-01

    system actively. The two groups used the system in their own way to support their specific activities and ways of working. The paper concludes that self-organized learning environments can strengthen the development of students’ academic as well as social qualifications. Further, the paper identifies......The purpose of the paper is to discuss the potentials of using a conference system in support of a project based university course. We use the concept of a self-organized learning environment to describe the shape of the course. In the paper we argue that educational technology, such as conference...... systems, has a potential to support students’ development of self-organized learning environments and facilitate self-governed activities in higher education. The paper is based on an empirical study of two project groups’ use of a conference system. The study showed that the students used the conference...

  6. Self-organization through random input by biological and machine systems - the pre-cognition sub-system

    International Nuclear Information System (INIS)

    Tahir Shah, K.

    1981-04-01

    We give an axiomatic prescription for self-organization in the brain and in intelligent machines through random input of data. This self-organization leads to the formation of pre-cognition long term memory (LTM) subsystem. By using the notions of p-equivalent and its negation instead of true and false in the predicate calculus and pre-cognition LTM, a method is proposed for pattern recognition which can also be utilized for studying relations between the genetic code and the observed properties of respective species. (author)

  7. Measuring the Complexity of Self-Organizing Traffic Lights

    Directory of Open Access Journals (Sweden)

    Darío Zubillaga

    2014-04-01

    Full Text Available We apply measures of complexity, emergence, and self-organization to an urban traffic model for comparing a traditional traffic-light coordination method with a self-organizing method in two scenarios: cyclic boundaries and non-orientable boundaries. We show that the measures are useful to identify and characterize different dynamical phases. It becomes clear that different operation regimes are required for different traffic demands. Thus, not only is traffic a non-stationary problem, requiring controllers to adapt constantly; controllers must also change drastically the complexity of their behavior depending on the demand. Based on our measures and extending Ashby’s law of requisite variety, we can say that the self-organizing method achieves an adaptability level comparable to that of a living system.

  8. Development and Evaluation of Sensor Concepts for Ageless Aerospace Vehicles: Report 6 - Development and Demonstration of a Self-Organizing Diagnostic System for Structural Health Monitoring

    Science.gov (United States)

    Batten, Adam; Edwards, Graeme; Gerasimov, Vadim; Hoschke, Nigel; Isaacs, Peter; Lewis, Chris; Moore, Richard; Oppolzer, Florien; Price, Don; Prokopenko, Mikhail; hide

    2010-01-01

    This report describes a significant advance in the capability of the CSIRO/NASA structural health monitoring Concept Demonstrator (CD). The main thrust of the work has been the development of a mobile robotic agent, and the hardware and software modifications and developments required to enable the demonstrator to operate as a single, self-organizing, multi-agent system. This single-robot system is seen as the forerunner of a system in which larger numbers of small robots perform inspection and repair tasks cooperatively, by self-organization. While the goal of demonstrating self-organized damage diagnosis was not fully achieved in the time available, much of the work required for the final element that enables the robot to point the video camera and transmit an image has been completed. A demonstration video of the CD and robotic systems operating will be made and forwarded to NASA.

  9. Monitoring of Thermal Protection Systems using Robust Self-Organizing Optical Fiber Sensing Networks

    Data.gov (United States)

    National Aeronautics and Space Administration — Effective thermal protection systems are crucial for spacecraft or future hypersonic transports re-entering the atmosphere. Micro-meteoroids and orbital debris...

  10. Information and self-organization a macroscopic approach to complex systems

    CERN Document Server

    Haken, Hermann

    1988-01-01

    Complex systems are ubiquitous, and practically all branches of science ranging from physics through chemistry and biology to economics and sociology have to deal with them. In this book we wish to present concepts and methods for dealing with complex systems from a unifying point of view. Therefore it may be of inter­ est to graduate students, professors and research workers who are concerned with theoretical work in the above-mentioned fields. The basic idea for our unified ap­ proach sterns from that of synergetics. In order to find unifying principles we shall focus our attention on those situations where a complex system changes its macroscopic behavior qualitatively, or in other words, where it changes its macroscopic spatial, temporal or functional structure. Until now, the theory of synergetics has usually begun with a microscopic or mesoscopic description of a complex system. In this book we present an approach which starts out from macroscopic data. In particular we shall treat systems that acquir...

  11. Monitoring of Thermal Protection Systems Using Robust Self-Organizing Optical Fiber Sensing Networks

    Science.gov (United States)

    Richards, Lance

    2013-01-01

    The general aim of this work is to develop and demonstrate a prototype structural health monitoring system for thermal protection systems that incorporates piezoelectric acoustic emission (AE) sensors to detect the occurrence and location of damaging impacts, and an optical fiber Bragg grating (FBG) sensor network to evaluate the effect of detected damage on the thermal conductivity of the TPS material. Following detection of an impact, the TPS would be exposed to a heat source, possibly the sun, and the temperature distribution on the inner surface in the vicinity of the impact measured by the FBG network. A similar procedure could also be carried out as a screening test immediately prior to re-entry. The implications of any detected anomalies in the measured temperature distribution will be evaluated for their significance in relation to the performance of the TPS during re-entry. Such a robust TPS health monitoring system would ensure overall crew safety throughout the mission, especially during reentry

  12. A systematic engineering tool chain approach for self-organizing building automation systems

    NARCIS (Netherlands)

    Mc Gibney, A.; Rea, S.; Lehmann, M.; Thior, S.; Lesecq, S.; Hendriks, M.; Guyon-Gardeux, C.; Mai, Linh Tuan; Pacull, F.; Ploennigs, J.; Basten, T.; Pesch, D.

    2013-01-01

    There is a strong push towards smart buildings that aim to achieve comfort, safety and energy efficiency, through building automation systems (BAS) that incorporate multiple subsystems such as heating and air-conditioning, lighting, access control etc. The design, commissioning and operation of BAS

  13. Monitoring of Thermal Protection Systems and MMOD using Robust Self-Organizing Optical Fiber Sensing Networks

    Science.gov (United States)

    Richards, Lance

    2014-01-01

    The general aim of this work is to develop and demonstrate a prototype structural health monitoring system for thermal protection systems that incorporates piezoelectric acoustic emission (AE) sensors to detect the occurrence and location of damaging impacts, such as those from Micrometeoroid Orbital Debris (MMOD). The approach uses an optical fiber Bragg grating (FBG) sensor network to evaluate the effect of detected damage on the thermal conductivity of the TPS material. Following detection of an impact, the TPS would be exposed to a heat source, possibly the sun, and the temperature distribution on the inner surface in the vicinity of the impact measured by the FBG network. A similar procedure could also be carried out as a screening test immediately prior to re-entry. The implications of any detected anomalies in the measured temperature distribution will be evaluated for their significance in relation to the performance of the TPS during reentry. Such a robust TPS health monitoring system would ensure overall crew safety throughout the mission, especially during reentry.

  14. A Novel Real-Time Coal Miner Localization and Tracking System Based on Self-Organized Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wang Yang

    2010-01-01

    Full Text Available With the development of information technology, we envision that the key of improving coal mine safety is how to get real-time positions of miners. In this paper, we propose a prototype system for real-time coal miner localization and tracking based on self-organized sensor networks. The system is composed of hardware and software platform. We develop a set of localization hardware devices with the Safety Certificate of Approval for Mining Products include miner node, wired fixed access station, and base with optical port. On the software side, we develop a layered software architecture of node application, server management, and information dissemination and broadcasting. We also develop three key localization technologies: an underground localization algorithm using received signal strength indication- (RSSI- verifying algorithm to reduce the influence of the severe environment in a coal mine; a robust fault-tolerant localization mechanism to improve the inherent defect of instability of RSSI localization; an accurate localization algorithm based on Monte Carlo localization (MCL to adapt to the underground tunnel structure. In addition, we conduct an experimental evaluation based on a real prototype implementation using MICA2 motes. The results show that our system is more accurate and more adaptive in general than traditional localization algorithms.

  15. Biologically-inspired approaches for self-organization, adaptation, and collaboration of heterogeneous autonomous systems

    Science.gov (United States)

    Steinberg, Marc

    2011-06-01

    This paper presents a selective survey of theoretical and experimental progress in the development of biologicallyinspired approaches for complex surveillance and reconnaissance problems with multiple, heterogeneous autonomous systems. The focus is on approaches that may address ISR problems that can quickly become mathematically intractable or otherwise impractical to implement using traditional optimization techniques as the size and complexity of the problem is increased. These problems require dealing with complex spatiotemporal objectives and constraints at a variety of levels from motion planning to task allocation. There is also a need to ensure solutions are reliable and robust to uncertainty and communications limitations. First, the paper will provide a short introduction to the current state of relevant biological research as relates to collective animal behavior. Second, the paper will describe research on largely decentralized, reactive, or swarm approaches that have been inspired by biological phenomena such as schools of fish, flocks of birds, ant colonies, and insect swarms. Next, the paper will discuss approaches towards more complex organizational and cooperative mechanisms in team and coalition behaviors in order to provide mission coverage of large, complex areas. Relevant team behavior may be derived from recent advances in understanding of the social and cooperative behaviors used for collaboration by tens of animals with higher-level cognitive abilities such as mammals and birds. Finally, the paper will briefly discuss challenges involved in user interaction with these types of systems.

  16. Effects of Random Environment on a Self-Organized Critical System: Renormalization Group Analysis of a Continuous Model

    Directory of Open Access Journals (Sweden)

    Antonov N.V.

    2016-01-01

    Full Text Available We study effects of the random fluid motion on a system in a self-organized critical state. The latter is described by the continuous stochastic model proposed by Hwa and Kardar [Phys. Rev. Lett. 62: 1813 (1989]. The advecting velocity field is Gaussian, not correlated in time, with the pair correlation function of the form ∝ δ(t − t′/k⊥d-1+ξ , where k⊥ = |k⊥| and k⊥ is the component of the wave vector, perpendicular to a certain preferred direction – the d-dimensional generalization of the ensemble introduced by Avellaneda and Majda [Commun. Math. Phys. 131: 381 (1990]. Using the field theoretic renormalization group we show that, depending on the relation between the exponent ξ and the spatial dimension d, the system reveals different types of large-scale, long-time scaling behaviour, associated with the three possible fixed points of the renormalization group equations. They correspond to ordinary diffusion, to passively advected scalar field (the nonlinearity of the Hwa–Kardar model is irrelevant and to the “pure” Hwa–Kardar model (the advection is irrelevant. For the special case ξ = 2(4 − d/3 both the nonlinearity and the advection are important. The corresponding critical exponents are found exactly for all these cases.

  17. Study of self-organization in network glasses and physical properties in some non-crystalline systems

    International Nuclear Information System (INIS)

    Mohamed, M.A.M.

    2007-01-01

    to understand the effects of structural features of the Ag-As-Te glassy system, various properties are separately studied as functions of the average coordination number (r). the relation between the chemical ordered covalent network model and the constraint theory, of the structural features, is examined. the self-organization model is widely used as a realistic description for the structure of both covalent glasses and amorphous solids. the overall mean energy, (E) , of a covalent network for the Ag-As-Te ternary glasses is determined. the average coordination number (r) for the Ag-As-Te system based on recently suggested models for network glasses has been examined. it was found that, two topological effects namely; the rigid to floppy transition and the structural transition, occurred resulting in some changes in the chemical ordering. the values of the glass transition temperature, T g were found to depend on the compositions. the thermal stability and the glass-forming tendency were calculated and they were found to have the same trend

  18. Life and understanding:the origins of ‘understanding’ in self-organizing nervous systems.

    Directory of Open Access Journals (Sweden)

    Yan Mark Yufik

    2016-12-01

    Full Text Available This article is motivated by the formulation of biotic self-organisation in (Friston, 2013, where the emergence of ‘life’ in coupled material entities (e.g., macromolecules was predicated on bounded subsets that maintain a degree of statistical independence from the rest of the network. Boundary elements in such systems or units constitute a Markov blanket; separating the internal states of the unit from its surrounding states. In this paper, we ask whether Markov blankets operate in the nervous system and underlie the development of intelligence, enabling a progression from the ability to sense the environment to the ability to understand it. Markov blankets have been previously hypothesized to form in neuronal networks as a result of phase transitions that cause network subsets to fold into bounded assemblies, or packets (Yufik, 1998a. The ensuing neuronal packets hypothesis builds on the notion of neuronal assemblies (Hebb, 1949, 1980, treating such assemblies as flexible but stable biophysical structures capable of withstanding entropic erosion. In other words, structures that maintain their integrity under changing conditions. In this treatment, neuronal packets give rise to perception of ’objects’; i.e., quasi-stable (stimulus bound groupings that are conserved over multiple presentations (e.g., the experience of perceiving ‘apple’ can be interrupted and resumed many times. Monitoring the variations in such groups enables the apprehension of behaviour; i.e., attributing to objects the ability to undergo changes without loss of self-identity. Ultimately, ‘understanding’ involves self-directed composition and manipulation of the ensuing ‘mental models’ that are constituted by neuronal packets, whose dynamics capture relationships among objects: that is, dependencies in the behaviour of objects under varying conditions. For example, movement is known to involve rotation of population vectors in the motor cortex

  19. E – urban systems

    Directory of Open Access Journals (Sweden)

    Franc J. Zakrajšek

    2000-01-01

    Full Text Available Information and tele-communication technology are increasingly affecting life and employment. According to predictions, more than 80% of all business operations will be carried out electronically through so called e-business. Recently even in Slovenia discussions have begun on “e-government”. Despite desired or undesired control, virtual networks are changing urban systems into e-urban systems. The extent of benefits to the public also depend on planners. The article presents concepts with the signature “e” to describe urban systems, day-to-day life, real-estate and simulation.

  20. A spiking neural network model of self-organized pattern recognition in the early mammalian olfactory system

    Science.gov (United States)

    Kaplan, Bernhard A.; Lansner, Anders

    2014-01-01

    Olfactory sensory information passes through several processing stages before an odor percept emerges. The question how the olfactory system learns to create odor representations linking those different levels and how it learns to connect and discriminate between them is largely unresolved. We present a large-scale network model with single and multi-compartmental Hodgkin–Huxley type model neurons representing olfactory receptor neurons (ORNs) in the epithelium, periglomerular cells, mitral/tufted cells and granule cells in the olfactory bulb (OB), and three types of cortical cells in the piriform cortex (PC). Odor patterns are calculated based on affinities between ORNs and odor stimuli derived from physico-chemical descriptors of behaviorally relevant real-world odorants. The properties of ORNs were tuned to show saturated response curves with increasing concentration as seen in experiments. On the level of the OB we explored the possibility of using a fuzzy concentration interval code, which was implemented through dendro-dendritic inhibition leading to winner-take-all like dynamics between mitral/tufted cells belonging to the same glomerulus. The connectivity from mitral/tufted cells to PC neurons was self-organized from a mutual information measure and by using a competitive Hebbian–Bayesian learning algorithm based on the response patterns of mitral/tufted cells to different odors yielding a distributed feed-forward projection to the PC. The PC was implemented as a modular attractor network with a recurrent connectivity that was likewise organized through Hebbian–Bayesian learning. We demonstrate the functionality of the model in a one-sniff-learning and recognition task on a set of 50 odorants. Furthermore, we study its robustness against noise on the receptor level and its ability to perform concentration invariant odor recognition. Moreover, we investigate the pattern completion capabilities of the system and rivalry dynamics for odor mixtures. PMID

  1. Self-organizing networks

    DEFF Research Database (Denmark)

    Marchetti, Nicola; Prasad, Neeli R.; Johansson, Johan

    2010-01-01

    In this paper, a general overview of Self-Organizing Networks (SON), and the rationale and state-of-the-art of wireless SON are first presented. The technical and business requirements are then briefly treated, and the research challenges within the field of SON are highlighted. Thereafter, the r...

  2. PREFACE: Self-organized nanostructures

    Science.gov (United States)

    Rousset, Sylvie; Ortega, Enrique

    2006-04-01

    the EUROCORES SONS Programme under the auspices of the European Science Foundation and the VI Framework Programme of the European Community. It was also funded by CNRS `formation permanente'. Major topics relevant to self-organization are covered in these papers. The first two papers deal with the physics of self-organized nucleation and growth. Both metal and semiconductor templates are investigated. The paper by Meyer zu Heringdorf focuses on the mesoscopic patterns formed by the Au-induced faceting of vicinal Si (001). Repain et al describe how uniform and long-range ordered nanostructures are built on a surface by using nucleation on a point-defect array. Electronic properties of such self-organized systems are reviewed by Mugarza and Ortega. The next three papers deal with molecules and self-organization. In the paper presented by Kröger, molecules are deposited on vicinal Au surfaces and are studied by STM. A very active field in self-organized nanostructures is the chemical route for nanoparticle synthesis. The paper by Piléni deals with self-organization of inorganic crystals produced by evaporation of a solution, also called colloids. Their physical properties are also treated. Gacoin et al illustrate chemical synthesis, including the template approach, using organized mesoporous silica films for the production of semiconductor or metal arrays of particles. An alternative method is developed in the paper by Allongue and Maroun which is the electrochemical method of building arrays of nanostructures. Ultimately, self-organization is a very interdisciplinary field. There is also an attempt in this issue to present some of the challenges using biology. The paper by Belamie et al deals with the self-assembly of biological macromolecules, such as chitin and collagen. Finally, Molodtsov and co-workers describe how a biological template can be used in order to achieve novel materials made of hybrid metallo-organic nanostructures.

  3. Concept and Feasibility Study of Self-Organized Electrochemical Devices

    National Research Council Canada - National Science Library

    Moorehead, William

    2002-01-01

    .... In this work, using attractive and repulsive London-van der Waals forces, a self-organized, interpenetrating, separator-free rechargeable lithium ion battery called a self-organized battery system (SBS) is proposed...

  4. Analyzing the Effectiveness of the Self-organized Public-Key Management System on MANETs under the Lack of Cooperation and the Impersonation Attacks

    Science.gov (United States)

    da Silva, Eduardo; Dos Santos, Aldri Luiz; Lima, Michele N.; Albini, Luiz Carlos Pessoa

    Among the key management schemes for MANETs, the Self-Organized Public-Key Management System (PGP-Like) is the main chaining-based key management scheme. It is fully self-organized and does not require any certificate authority. Two kinds of misbehavior attacks are considered to be great threats to PGP-Like: lack of cooperation and impersonation attacks. This work quantifies the impact of such attacks on the PGP-Like. Simulation results show that PGP-Like was able to maintain its effectiveness when submitted to the lack of cooperation attack, contradicting previously theoretical results. It correctly works even in the presence of more than 60% of misbehaving nodes, although the convergence time is affected with only 20% of misbehaving nodes. On the other hand, PGP-Like is completely vulnerable to the impersonation attack. Its functionality is affected with just 5% of misbehaving nodes, confirming previously theoretical results.

  5. Self-organization in irregular landscapes: Detecting autogenic interactions from field data using descriptive statistics and dynamical systems theory

    Science.gov (United States)

    Larsen, L.; Watts, D.; Khurana, A.; Anderson, J. L.; Xu, C.; Merritts, D. J.

    2015-12-01

    The classic signal of self-organization in nature is pattern formation. However, the interactions and feedbacks that organize depositional landscapes do not always result in regular or fractal patterns. How might we detect their existence and effects in these "irregular" landscapes? Emergent landscapes such as newly forming deltaic marshes or some restoration sites provide opportunities to study the autogenic processes that organize landscapes and their physical signatures. Here we describe a quest to understand autogenic vs. allogenic controls on landscape evolution in Big Spring Run, PA, a landscape undergoing restoration from bare-soil conditions to a target wet meadow landscape. The contemporary motivation for asking questions about autogenic vs. allogenic controls is to evaluate how important initial conditions or environmental controls may be for the attainment of management objectives. However, these questions can also inform interpretation of the sedimentary record by enabling researchers to separate signals that may have arisen through self-organization processes from those resulting from environmental perturbations. Over three years at Big Spring Run, we mapped the dynamic evolution of floodplain vegetation communities and distributions of abiotic variables and topography. We used principal component analysis and transition probability analysis to detect associative interactions between vegetation and geomorphic variables and convergent cross-mapping on lidar data to detect causal interactions between biomass and topography. Exploratory statistics revealed that plant communities with distinct morphologies exerted control on landscape evolution through stress divergence (i.e., channel initiation) and promoting the accumulation of fine sediment in channels. Together, these communities participated in a negative feedback that maintains low energy and multiple channels. Because of the spatially explicit nature of this feedback, causal interactions could not

  6. Self-organizing representations

    Energy Technology Data Exchange (ETDEWEB)

    Kohonen, T.

    1983-01-01

    A property which is commonplace in the brain but which has always been ignored in learning machines is the spatial order of the processing units. This order is clearly highly significant and in nature it develops gradually during the lifetime of the organism. It then serves as the basis for perceptual and cognitive processes, and memory, too. The spatial order in biological organisms is often believed to be genetically determined. It is therefore intriguing to learn that a meaningful and optimal spatial order is formed in an extremely simple self-organizing process whereby certain feature maps are formed automatically. 8 references.

  7. Strategies and Rubrics for Teaching Chaos and Complex Systems Theories as Elaborating, Self-Organizing, and Fractionating Evolutionary Systems

    Science.gov (United States)

    Fichter, Lynn S.; Pyle, E. J.; Whitmeyer, S. J.

    2010-01-01

    To say Earth systems are complex, is not the same as saying they are a complex system. A complex system, in the technical sense, is a group of -agents (individual interacting units, like birds in a flock, sand grains in a ripple, or individual units of friction along a fault zone), existing far from equilibrium, interacting through positive and…

  8. Urban mining systems

    CERN Document Server

    Nakamura, Takashi

    2015-01-01

    This book focuses on the fundamental concept of and current endeavors in “urban mining” among those who are interested in both metal resources and ecology. Systems for recycling and reusing precious metals and rare-earth minerals contained in used and discarded electronics are introduced in this book. The target audience is not academic researchers in the resource management and ecology fields but, rather, citizens who are concerned about our future environment and want to do something for the future.

  9. Self Organization in Compensated Semiconductors

    Science.gov (United States)

    Berezin, Alexander A.

    2004-03-01

    In partially compensated semiconductor (PCS) Fermi level is pinned to donor sub-band. Due to positional randomness and almost isoenergetic hoppings, donor-spanned electronic subsystem in PCS forms fluid-like highly mobile collective state. This makes PCS playground for pattern formation, self-organization, complexity emergence, electronic neural networks, and perhaps even for origins of life, bioevolution and consciousness. Through effects of impact and/or Auger ionization of donor sites, whole PCS may collapse (spinodal decomposition) into microblocks potentially capable of replication and protobiological activity (DNA analogue). Electronic screening effects may act in RNA fashion by introducing additional length scale(s) to system. Spontaneous quantum computing on charged/neutral sites becomes potential generator of informationally loaded microstructures akin to "Carl Sagan Effect" (hidden messages in Pi in his "Contact") or informational self-organization of "Library of Babel" of J.L. Borges. Even general relativity effects at Planck scale (R.Penrose) may affect the dynamics through (e.g.) isotopic variations of atomic mass and local density (A.A.Berezin, 1992). Thus, PCS can serve as toy model (experimental and computational) at interface of physics and life sciences.

  10. Theoretical foundation for the discrete dynamics of physicochemical systems: Chaos, self-organization, time and space in complex systems

    Directory of Open Access Journals (Sweden)

    V. Gontar

    1997-01-01

    Full Text Available A new theoretical foundation for the discrete dynamics of physicochemical systems is presented. Based on the analogy between the π-theorem of the theory of dimensionality, the second law of thermodynamics and the stoichiometry of complex physicochemical reactions, basic dynamic equations and an extreme principle were formulated. The meaning of discrete time and space in the proposed equations is discussed. Some results of numerical calculations are presented to demonstrate the potential of the proposed approach to the mathematical simulation of spatiotemporal physicochemical reaction dynamics.

  11. Self-Organization, Resilience and Robustness of Complex Systems Through an Application to Financial Market from an Agent-Based Approach

    Science.gov (United States)

    Lucas, Iris; Cotsaftis, Michel; Bertelle, Cyrille

    This paper introduces the implementation of a computational agent-based financial market model in which the system is described on both microscopic and macroscopic levels. This artificial financial market model is used to study the system response when a shock occurs. Indeed, when a market experiences perturbations, financial systems behavior can exhibit two different properties: resilience and robustness. Through simulations and different scenarios of market shocks, these system properties are studied. The results notably show that the emergence of collective herding behavior when market shock occurs leads to a temporary disruption of the system self-organization. Numerical simulations highlight that the market can absorb strong mono-shocks but can also be led to rupture by low but repeated perturbations.

  12. Self-organization phenomena in plasma physics

    International Nuclear Information System (INIS)

    Sanduloviciu, M.; Popescu, S.

    2001-01-01

    The self-assembling in nature and laboratory of structures in systems away from thermodynamic equilibrium is one of the problems that mostly fascinates the scientists working in all branches of science. In this context a substantial progress has been obtained by investigating the appearance of spatial and spatiotemporal patterns in plasma. These experiments revealed the presence of a scenario of self-organization able to suggest an answer to the central problem of the 'Science of Complexity', why matter transits spontaneously from a disordered into an ordered state? Based on this scenario of self-organization we present arguments proving the possibility to explain the challenging problems of nonequilibrium physics in general. These problems refer to: (i) genuine origin of phase transitions observed in gaseous conductors and semiconductors; (ii) the elucidation of the role played by self-organization in the simulation of oscillations; (iii) the physical basis of anomalous transport of matter and energy with special reference to the possibilities of improving the economical performance of fusion devices; (iv) the possibility to use self-confined gaseous space charged configurations as an alternative to the magnetically confined plasma used at present in fusion devices. In other branches of sciences, as for instance in Biology, the self-organization scenario reveals a new insight into a mechanism able to explain the appearance of the simplest possible space charge configuration able to evolve, under suitable conditions, into prebiotic structures. Referring to phenomena observed in nature, the same self-organization scenario suggests plausible answers to the appearance of ball lightening but also to the origin of the flickering phenomena observed in the light emission of the Sun and stars. For theory the described self-organization scenario offers a new physical basis for many problems of nonlinear science not solved yet and also a new model for the so-called 'self

  13. Development of a Real-Time Thermal Performance Diagnostic Monitoring system Using Self-Organizing Neural Network for Kori-2 Nuclear Power Unit

    International Nuclear Information System (INIS)

    Kang, Hyun Gook; Seong, Poong Hyun

    1996-01-01

    In this work, a PC-based thermal performance monitoring system is developed for the nuclear power plants. the system performs real-time thermal performance monitoring and diagnosis during plant operation. Specifically, a prototype for the Kori-2 nuclear power unit is developed and examined is very difficult because the system structure is highly complex and the components are very much inter-related. In this study, some major diagnostic performance parameters are selected in order to represent the thermal cycle effectively and to reduce the computing time. The Fuzzy ARTMAP, a self-organizing neural network, is used to recognize the characteristic pattern change of the performance parameters in abnormal situation. By examination, the algorithm is shown to be ale to detect abnormality and to identify the fault component or the change of system operation condition successfully. For the convenience of operators, a graphical user interface is also constructed in this work. 5 figs., 3 tabs., 11 refs. (Author)

  14. Self-organization, Networks, Future

    Directory of Open Access Journals (Sweden)

    T. S. Akhromeyeva

    2013-01-01

    Full Text Available This paper presents an analytical review of a conference on the great scientist, a brilliant professor, an outstanding educator Sergei Kapitsa, held in November 2012. In the focus of this forum were problems of self-organization and a paradigm of network structures. The use of networks in the context of national defense, economics, management of mass consciousness was discussed. The analysis of neural networks in technical systems, the structure of the brain, as well as in the space of knowledge, information, and behavioral strategies plays an important role. One of the conference purposes was to an online organize community in Russia and to identify the most promising directions in this field. Some of them are presented in this paper.

  15. Self-organization through decoupling

    Directory of Open Access Journals (Sweden)

    Romar Correa

    2000-01-01

    Full Text Available In one line of research, the transition from Fordism to flexible specialisation is explained by the infeasibility of a mode of regulation that relied on central controls. According to another explanation, which we favour, the disintegration of vertically integrated production is unpredictable. The concept of self-organization is often recommended to model the transition from hierarchical organizational forms to flatter structures. Formally, a conditionally stable nonlinear system of differential equations is examined. In the first thesis, the characteristic roots with positive real parts play the role of ‘order’ parameters which can become unstable modes. The rest of the variables refer to stable modes. The strategy is to show that the stable modes can be expressed in terms of the unstable modes so that the former can be eliminated from the system. On the other hand, we provide a theorem showing that a coupled set of differential equations can become uncoupled and vice versa as an argument in favour of the second thesis. The path of evolution can turn both ways.

  16. Quantum self-organization and nuclear collectivities

    Science.gov (United States)

    Otsuka, T.; Tsunoda, Y.; Togashi, T.; Shimizu, N.; Abe, T.

    2018-02-01

    The quantum self-organization is introduced as one of the major underlying mechanisms of the quantum many-body systems. In the case of atomic nuclei as an example, two types of the motion of nucleons, single-particle states and collective modes, dominate the structure of the nucleus. The outcome of the collective mode is determined basically by the balance between the effect of the mode-driving force (e.g., quadrupole force for the ellipsoidal deformation) and the resistance power against it. The single-particle energies are one of the sources to produce such resistance power: a coherent collective motion is more hindered by larger gaps between relevant single particle states. Thus, the single-particle state and the collective mode are “enemies” each other. However, the nuclear forces are demonstrated to be rich enough so as to enhance relevant collective mode by reducing the resistance power by changing singleparticle energies for each eigenstate through monopole interactions. This will be verified with the concrete example taken from Zr isotopes. Thus, when the quantum self-organization occurs, single-particle energies can be self-organized, being enhanced by (i) two quantum liquids, e.g., protons and neutrons, (ii) two major force components, e.g., quadrupole interaction (to drive collective mode) and monopole interaction (to control resistance). In other words, atomic nuclei are not necessarily like simple rigid vases containing almost free nucleons, in contrast to the naïve Fermi liquid picture. Type II shell evolution is considered to be a simple visible case involving excitations across a (sub)magic gap. The quantum self-organization becomes more important in heavier nuclei where the number of active orbits and the number of active nucleons are larger. The quantum self-organization is a general phenomenon, and is expected to be found in other quantum systems.

  17. Effect of a lanthanide ion on the micellation and self-organization of lyotropic liquid crystal systems

    International Nuclear Information System (INIS)

    Selivanova, N.M.; Osipova, V.V.; Galyametdinov, Yu.G.

    2006-01-01

    Lanthanide-containing lyotropic liquid-crystalline systems were synthesized and their phase behavior, as well as the micellar behavior of aqueous solutions of decaethylene glycol monodecyl ether in the absence and presence of a lanthanide ion, were studied. Tensimetry and conductometry were used to determine the critical micellation concentration, and the values obtained by these methods were found to be in close agreement with each other. Polarization microscopy observations showed that, in concentrated aqueous solutions, ordered lyotropic mesophases arise. The parameters of the phase transitions in the systems under study were determined. The mesophase obtained was demonstrated to have a 2D hexagonal supramolecular structure [ru

  18. 物流战略联盟自组织演化的系统动力学机理%Systems Dynamic Mechanism of Self-organizing Evolution of Logistics Strategic Alliances

    Institute of Scientific and Technical Information of China (English)

    华光; 范敏; 孙东泉; 李嫄

    2013-01-01

    In this paper,starting from the connotation of self-organization of alliances,we considered comprehensively the characteristic of logistics strategic alliances,studied the mechanism for its self-organizing evolution and adopted the method of systems dynamics to build the self-organizing evolution equation for the logistics strategic alliances.%从联盟自组织内涵出发,综合考虑物流战略联盟自身的特性,研究其自组织演化的机制,并采用系统动力学方法建构物流战略联盟的自组织演化方程,为物流企业选择战略合作途径与模式提供决策依据.

  19. Redundancy in Systems Which Entertain a Model of Themselves: Interaction Information and the Self-Organization of Anticipation

    Directory of Open Access Journals (Sweden)

    Loet Leydesdorff

    2010-01-01

    Full Text Available Mutual information among three or more dimensions (μ* = –Q has been considered as interaction information. However, Krippendorff [1,2] has shown that this measure cannot be interpreted as a unique property of the interactions and has proposed an alternative measure of interaction information based on iterative approximation of maximum entropies. Q can then be considered as a measure of the difference between interaction information and redundancy generated in a model entertained by an observer. I argue that this provides us with a measure of the imprint of a second-order observing system—a model entertained by the system itself—on the underlying information processing. The second-order system communicates meaning hyper-incursively; an observation instantiates this meaning-processing within the information processing. The net results may add to or reduce the prevailing uncertainty. The model is tested empirically for the case where textual organization can be expected to contain intellectual organization in terms of distributions of title words, author names, and cited references.

  20. Civil Society as a Self-Organizing Social System and the State: Some Objections to the Hegel Concept

    Directory of Open Access Journals (Sweden)

    Ludmila J. Grudtsina

    2014-03-01

    Full Text Available In the present article author attempts by using different scientific methods used in synergy, to propose an alternative formula to the formula of Hegelian distinction of civil society and state, that are not as different and competing with each other systems as well as the necessary elements to each other converge single social system. This scientific idea is presented in an arithmetic progression in civil society - "mass", next level - the civil society itself, realizing itself, advancing and increasingly, next level – the legal state (ideal for which to strive. In this case, the state will not be the term, but the result in the formula. In the conclusion, author concludes that one can not ignore responsibility of authorities, seeking in the modern world to create institutes of civil society. Taking into account that this generally positive process can be used as a special instrument of government, including the effective management of the objective processes in society, where the presence of democratic prerequisites, no matter how weak they are, civil society inevitably grows up.

  1. Information Driven Ecohydrologic Self-Organization

    Directory of Open Access Journals (Sweden)

    Benjamin L. Ruddell

    2010-09-01

    Full Text Available Variability plays an important role in the self-organized interaction between vegetation and its environment, yet the principles that characterize the role of the variability in these interactions remain elusive. To address this problem, we study the dependence between a number of variables measured at flux towers by quantifying the information flow between the different variables along with the associated time lag. By examining this network of feedback loops for seven ecosystems in different climate regions, we find that: (1 the feedback tends to maximize information production in the entire system, and the latter increases with increasing variability within the whole system; and (2 variables that participate in feedback exhibit moderated variability. Self-organization arises as a tradeoff where the ability of the total system to maximize information production through feedback is limited by moderate variability of the participating variables. This relationship between variability and information production leads to the emergence of ordered organization.

  2. Relativistic fluid theories - Self organization

    International Nuclear Information System (INIS)

    Mahajan, S.M.; Hazeltine, R.D.; Yoshida, Z.

    2003-01-01

    Developments in two distinct but related subjects are reviewed: 1) Formulation and investigation of closed fluid theories which transcend the limitations of standard magnetohydrodynamics (MHD), in particular, theories which are valid in the long mean free path limit and in which pressure anisotropy, heat flow, and arbitrarily strong sheared flows are treated consistently, and 2) Exploitation of the two-fluid theories to derive new plasma configurations in which the flow-field is a co-determinant of the overall dynamics; some of these states belong to the category of self-organized relaxed states. Physical processes which may provide a route to self-organization and complexity are also explored. (author)

  3. Cleanly: trashducation urban system

    DEFF Research Database (Denmark)

    Reif, Inbal; Alt, Florian; Ramos, Juan David Hincapie

    Half the world's population is expected to live in urban areas by 2020. The high human density and changes in peoples' consumption habits result in an ever-increasing amount of trash that must be handled by governing bodies. Problems created by inefficient or dysfunctional cleaning services are e......, which not only motivates our research but also provides useful information on reasons and possible solutions for trash problems....

  4. Self-organizing of critical state in granulated superconductors

    International Nuclear Information System (INIS)

    Ginzburg, S.L.; Savitskaya, N.E.

    2000-01-01

    Critical state in granulated superconductors was studied on the basis of two mathematical models - the system of differential equations for calibration and invariant difference of phases and a simplified model describing the system of associated images and equivalent to the standard models to study self-organizing criticality. The critical state of granulated superconductors in all studied cases was shown to be self-organized. Besides, it is shown that the applied models are practically equivalent ones, that is they both show similar critical behavior and lead to coincidence of noncritical phenomena. For the first time one showed that the occurrence of self-organized critically within the system of nonlinear differential equations and its equivalence to self-organized critically in the standard models [ru

  5. Emergence or self-organization?: Look to the soil population.

    Science.gov (United States)

    Addiscott, Tom

    2011-07-01

    EMERGENCE IS NOT WELL DEFINED, BUT ALL EMERGENT SYSTEMS HAVE THE FOLLOWING CHARACTERISTICS: the whole is more than the sum of the parts, they show bottom-up rather top-down organization and, if biological, they involve chemical signaling. Self-organization can be understood in terms of the second and third stages of thermodynamics enabling these stages used as analogs of ecosystem functioning. The second stage system was suggested earlier to provide a useful analog of the behavior of natural and agricultural ecosystems subjected to perturbations, but for this it needs the capacity for self-organization. Considering the hierarchy of the ecosystem suggests that this self-organization is provided by the third stage, whose entropy maximization acts as an analog of that of the soil population when it releases small molecules from much larger molecules in dead plant matter. This it does as vigorously as conditions allow. Through this activity, the soil population confers self-organization at both the ecosystem and the global level. The soil population has been seen as both emergent and self-organizing, supporting the suggestion that the two concepts are are so closely linked as to be virtually interchangeable. If this idea is correct one of the characteristics of a biological emergent system seems to be the ability to confer self-organization on an ecosystem or other entity which may be larger than itself. The beehive and the termite colony are emergent systems which share this ability.

  6. Optical electronics self-organized integration and applications

    CERN Document Server

    Yoshimura, Tetsuzo

    2012-01-01

    IntroductionFrom Electronics to Optical ElectronicsAnalysis Tools for Optical CircuitsSelf-Organized Optical Waveguides: Theoretical AnalysisSelf-Organized Optical Waveguides: Experimental DemonstrationsOptical Waveguide Films with Vertical Mirrors 3-D Optical Circuits with Stacked Waveguide Films Heterogeneous Thin-Film Device IntegrationOptical Switches OE Hardware Built by Optical ElectronicsIntegrated Solar Energy Conversion SystemsFuture Challenges.

  7. Complexity in plasma: From self-organization to geodynamo

    International Nuclear Information System (INIS)

    Sato, T.

    1996-01-01

    A central theme of open-quote open-quote Complexity close-quote close-quote is the question of the creation of ordered structure in nature (self-organization). The assertion is made that self-organization is governed by three key processes, i.e., energy pumping, entropy expulsion and nonlinearity. Extensive efforts have been done to confirm this assertion through computer simulations of plasmas. A system exhibits markedly different features in self-organization, depending on whether the energy pumping is instantaneous or continuous, or whether the produced entropy is expulsed or reserved. The nonlinearity acts to bring a nonequilibrium state into a bifurcation, thus resulting in a new structure along with an anomalous entropy production. As a practical application of our grand view of self-organization a preferential generation of a dipole magnetic field is successfully demonstrated. copyright 1996 American Institute of Physics

  8. Self-organizing magnetohydrodynamic plasma

    International Nuclear Information System (INIS)

    Sato, T.; Horiuchi, R.; Watanabe, K.; Hayashi, T.; Kusano, K.

    1990-09-01

    In a resistive magnetohydrodynamic (MHD) plasma, both the magnetic energy and the magnetic helicity dissipate with the resistive time scale. When sufficiently large free magnetic energy does exist, however, an ideal current driven instability is excited whereby magnetic reconnection is driven at a converging point of induced plasma flows which does exist in a bounded compressible plasma. At a reconnection point excess free energy (entropy) is rapidly dissipated by ohmic heating and lost by radiation, while magnetic helicity is completely conserved. The magnetic topology is largely changed by reconnection and a new ordered structure with the same helicity is created. It is discussed that magnetic reconnection plays a key role in the MHD self-organization process. (author)

  9. Self-organization in irradiated materials

    International Nuclear Information System (INIS)

    Gerasimenko, N.N.; Dzhamanbalin, K.K.; Medetov, N.A.

    2003-01-01

    Full text: By the present time a great deal of experimental material concerning self-organization in irradiated materials is stored. It means that in different materials (single crystal and amorphous semiconductor, metals, polymers) during one process of irradiation with accelerated particles or energetic quanta the structure previously disordered can be reordered to the previous or different order. These processes are considered separately from the processes of radiation-stimulated ordering when the renewal of the structure occurs as the result of extra irradiation, sometimes accompanied with another influence (heating, lighting, application of mechanical tensions). The processes of reordering are divided into two basic classes: the reconstruction of crystalline structure (1) and the formation of space-ordered system (2). The processes of ordering are considered with the use of synergetic approach and are analyzed conformably to the concrete conditions of new order appearance process realization in order to reveal the self-organization factor's role. The concrete experimental results of investigating of the radiation ordering processes are analyzed for different materials: semiconductor, metals, inorganic dielectrics, polymers. The ordering processes are examined from the point of their possible use in the technology of creating nano-dimensional structures general and quantum-dimensional ones in particular

  10. Hierarchical organization versus self-organization

    OpenAIRE

    Busseniers, Evo

    2014-01-01

    In this paper we try to define the difference between hierarchical organization and self-organization. Organization is defined as a structure with a function. So we can define the difference between hierarchical organization and self-organization both on the structure as on the function. In the next two chapters these two definitions are given. For the structure we will use some existing definitions in graph theory, for the function we will use existing theory on (self-)organization. In the t...

  11. Order out of Randomness: Self-Organization Processes in Astrophysics

    Science.gov (United States)

    Aschwanden, Markus J.; Scholkmann, Felix; Béthune, William; Schmutz, Werner; Abramenko, Valentina; Cheung, Mark C. M.; Müller, Daniel; Benz, Arnold; Chernov, Guennadi; Kritsuk, Alexei G.; Scargle, Jeffrey D.; Melatos, Andrew; Wagoner, Robert V.; Trimble, Virginia; Green, William H.

    2018-03-01

    Self-organization is a property of dissipative nonlinear processes that are governed by a global driving force and a local positive feedback mechanism, which creates regular geometric and/or temporal patterns, and decreases the entropy locally, in contrast to random processes. Here we investigate for the first time a comprehensive number of (17) self-organization processes that operate in planetary physics, solar physics, stellar physics, galactic physics, and cosmology. Self-organizing systems create spontaneous " order out of randomness", during the evolution from an initially disordered system to an ordered quasi-stationary system, mostly by quasi-periodic limit-cycle dynamics, but also by harmonic (mechanical or gyromagnetic) resonances. The global driving force can be due to gravity, electromagnetic forces, mechanical forces (e.g., rotation or differential rotation), thermal pressure, or acceleration of nonthermal particles, while the positive feedback mechanism is often an instability, such as the magneto-rotational (Balbus-Hawley) instability, the convective (Rayleigh-Bénard) instability, turbulence, vortex attraction, magnetic reconnection, plasma condensation, or a loss-cone instability. Physical models of astrophysical self-organization processes require hydrodynamic, magneto-hydrodynamic (MHD), plasma, or N-body simulations. Analytical formulations of self-organizing systems generally involve coupled differential equations with limit-cycle solutions of the Lotka-Volterra or Hopf-bifurcation type.

  12. Self-organized natural roads for predicting traffic flow: a sensitivity study

    International Nuclear Information System (INIS)

    Jiang, Bin; Zhao, Sijian; Yin, Junjun

    2008-01-01

    In this paper, we extended road-based topological analysis to both nationwide and urban road networks, and concentrated on a sensitivity study with respect to the formation of self-organized natural roads based on the Gestalt principle of good continuity. Both annual average daily traffic (AADT) and global positioning system (GPS) data were used to correlate with a series of ranking metrics including five centrality-based metrics and two PageRank metrics. It was found that there exists a tipping point from segment-based to road-based network topology in terms of correlation between ranking metrics and their traffic. To our great surprise, (1) this correlation is significantly improved if a selfish rather than utopian strategy is adopted in forming the self-organized natural roads, and (2) point-based metrics assigned by summation into individual roads tend to have a much better correlation with traffic flow than line-based metrics. These counter-intuitive surprising findings constitute emergent properties of self-organized natural roads, which are intelligent enough for predicting traffic flow, thus shedding substantial light on the understanding of road networks and their traffic from the perspective of complex networks

  13. Understanding complex urban systems integrating multidisciplinary data in urban models

    CERN Document Server

    Gebetsroither-Geringer, Ernst; Atun, Funda; Werner, Liss

    2016-01-01

    This book is devoted to the modeling and understanding of complex urban systems. This second volume of Understanding Complex Urban Systems focuses on the challenges of the modeling tools, concerning, e.g., the quality and quantity of data and the selection of an appropriate modeling approach. It is meant to support urban decision-makers—including municipal politicians, spatial planners, and citizen groups—in choosing an appropriate modeling approach for their particular modeling requirements. The contributors to this volume are from different disciplines, but all share the same goal: optimizing the representation of complex urban systems. They present and discuss a variety of approaches for dealing with data-availability problems and finding appropriate modeling approaches—and not only in terms of computer modeling. The selection of articles featured in this volume reflect a broad variety of new and established modeling approaches such as: - An argument for using Big Data methods in conjunction with Age...

  14. Patterns identification in supervisory systems of nuclear reactors installations and gas pipelines systems using self-organizing maps; Identificacao de padroes em sistemas supervisorios de instalacoes de reatores nucleares e em sistemas de gasodutos utilizando mapas auto-organizaveis

    Energy Technology Data Exchange (ETDEWEB)

    Doraskevicius Junior, Waldemar

    2005-07-01

    Self-Organizing Maps, SOM, of Kohonen were studied, implemented and tested with the aim of developing, for the energy branch, an effective tool especially for transient identification in nuclear reactors and for gas pipelines networks logistic supervision, by classifying operations and identifying transients or abnormalities. The digital system for the test was developed in Java platform, for the portability and scalability, and for belonging to free development platforms. The system, executed in personal computers, showed satisfactory results to aid in decision taking, by classifying IRIS (International Reactor Innovative and Secure) reactor operation conditions (data from simulator) and by classifying Southeast (owner: TRANSPETRO - Brazil) gas pipeline network. Various adaptations were needed for such business, as new topologies for the output layer of artificial neural network and particular preparation for the input data. (author)

  15. Hidden linkages between urbanization and food systems.

    Science.gov (United States)

    Seto, Karen C; Ramankutty, Navin

    2016-05-20

    Global societies are becoming increasingly urban. This shift toward urban living is changing our relationship with food, including how we shop and what we buy, as well as ideas about sanitation and freshness. Achieving food security in an era of rapid urbanization will require considerably more understanding about how urban and food systems are intertwined. Here we discuss some potential understudied linkages that are ripe for further examination. Copyright © 2016, American Association for the Advancement of Science.

  16. System and method employing a self-organizing map load feature database to identify electric load types of different electric loads

    Science.gov (United States)

    Lu, Bin; Harley, Ronald G.; Du, Liang; Yang, Yi; Sharma, Santosh K.; Zambare, Prachi; Madane, Mayura A.

    2014-06-17

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a self-organizing map load feature database of a plurality of different electric load types and a plurality of neurons, each of the load types corresponding to a number of the neurons; employing a weight vector for each of the neurons; sensing a voltage signal and a current signal for each of the loads; determining a load feature vector including at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the loads; and identifying by a processor one of the load types by relating the load feature vector to the neurons of the database by identifying the weight vector of one of the neurons corresponding to the one of the load types that is a minimal distance to the load feature vector.

  17. Self-organized criticality paradigm

    International Nuclear Information System (INIS)

    Duran, I.; Stoeckel, J.; Hron, M.; Horacek, J.; Jakubka, K.; Kryska, L.

    2000-01-01

    According to the paradigm of the Self-Organized Criticality (SOC), the anomalous transport in tokamaks is caused by fast transient processes - avalanches. One of the manifestations of these phenomena should be 1/f decay of electrostatic fluctuations power spectra in a certain frequency range. In this paper, the frequency spectra of floating potential, density and fluctuation-induced flux, measured by poloidal and radial arrays of Langmuir probes on the CASTOR tokamak, are presented. The floating potential and the fluctuation-induced flux decay from 30 kHz up to 100 kHz as f -1 . The plasma density decays as f -1 in a more narrow band, 20 to 40 kHz. The possible limitation of SOC behavior for frequencies higher than 100 kHz due to intermittency is stressed. For this reason the Probability Distribution Functions (PDFs) of floating potential fluctuations were computed at different time scales using wavelet transform. A clear departure of the computed PDFs from Gaussianity, which is a classical signature of intermittency, is observed at time scales under 10 μs (100 kHz). (author)

  18. Urban Space Explorer: A Visual Analytics System for Urban Planning.

    Science.gov (United States)

    Karduni, Alireza; Cho, Isaac; Wessel, Ginette; Ribarsky, William; Sauda, Eric; Dou, Wenwen

    2017-01-01

    Understanding people's behavior is fundamental to many planning professions (including transportation, community development, economic development, and urban design) that rely on data about frequently traveled routes, places, and social and cultural practices. Based on the results of a practitioner survey, the authors designed Urban Space Explorer, a visual analytics system that utilizes mobile social media to enable interactive exploration of public-space-related activity along spatial, temporal, and semantic dimensions.

  19. 9th Workshop on Self-Organizing Maps

    CERN Document Server

    Príncipe, José; Zegers, Pablo

    2013-01-01

    Self-organizing maps (SOMs) were developed by Teuvo Kohonen in the early eighties. Since then more than 10,000 works have been based on SOMs. SOMs are unsupervised neural networks useful for clustering and visualization purposes. Many SOM applications have been developed in engineering and science, and other fields. This book contains refereed papers presented at the 9th Workshop on Self-Organizing Maps (WSOM 2012) held at the Universidad de Chile, Santiago, Chile, on December 12-14, 2012. The workshop brought together researchers and practitioners in the field of self-organizing systems. Among the book chapters there are excellent examples of the use of SOMs in agriculture, computer science, data visualization, health systems, economics, engineering, social sciences, text and image analysis, and time series analysis. Other chapters present the latest theoretical work on SOMs as well as Learning Vector Quantization (LVQ) methods.

  20. Synergetic Development Assessment of Urban River System Landscapes

    Directory of Open Access Journals (Sweden)

    Jingya Qiao

    2017-11-01

    Full Text Available This paper presents Synergetic Development Assessment (SDA as a methodology to evaluate the environmental, economic, and social performance of an urban river system landscape from the perspective of sustainability. SDA is based on synergetics and its “order parameters” theory, proposed as a science to study the self-organization of complex systems. A case study of river system landscapes in China was carried out by, first, simplifying the composite system into three subsystems: environmental, economic, and social; then, going on to construct a hierarchical structure to explore the order parameters as the evaluation index. The Analytic Hierarchy Process was used to get the weight of the evaluation index to complete the assessment index system. At the same time, a Sequential Synergy Degree Model was built to accomplish the SDA. We find that from 2005 to 2015, the order degree of the environmental subsystem developed slowly, with fluctuations, and that river pattern is the key factor. Meanwhile, the order degree of the economic subsystem fluctuated widely, which significantly depended on the changing value of water resources, and the order degree of social subsystem improved continuously, with social culture lagging far behind. As a whole, the synergy degree of the composite system developed orderly at a corresponding low level, which was in low synergy from 2005 to 2009 and then in general synergy up to 2015.

  1. Atmospheric Convective Organization: Self-Organized Criticality or Homeostasis?

    Science.gov (United States)

    Yano, Jun-Ichi

    2015-04-01

    Atmospheric convection has a tendency organized on a hierarchy of scales ranging from the mesoscale to the planetary scales, with the latter especially manifested by the Madden-Julian oscillation. The present talk examines two major possible mechanisms of self-organization identified in wider literature from a phenomenological thermodynamic point of view by analysing a planetary-scale cloud-resolving model simulation. The first mechanism is self-organized criticality. A saturation tendency of precipitation rate with the increasing column-integrated water, reminiscence of critical phenomena, indicates self-organized criticality. The second is a self-regulation mechanism that is known as homeostasis in biology. A thermodynamic argument suggests that such self-regulation maintains the column-integrated water below a threshold by increasing the precipitation rate. Previous analyses of both observational data as well as cloud-resolving model (CRM) experiments give mixed results. A satellite data analysis suggests self-organized criticality. Some observational data as well as CRM experiments support homeostasis. Other analyses point to a combination of these two interpretations. In this study, a CRM experiment over a planetary-scale domain with a constant sea-surface temperature is analyzed. This analysis shows that the relation between the column-integrated total water and precipitation suggests self-organized criticality, whereas the one between the column-integrated water vapor and precipitation suggests homeostasis. The concurrent presence of these two mechanisms are further elaborated by detailed statistical and budget analyses. These statistics are scale invariant, reflecting a spatial scaling of precipitation processes. These self-organization mechanisms are most likely be best theoretically understood by the energy cycle of the convective systems consisting of the kinetic energy and the cloud-work function. The author has already investigated the behavior of this

  2. Self-Organization during Friction in Complex Surface Engineered Tribosystems

    Directory of Open Access Journals (Sweden)

    Ben D. Beake

    2010-02-01

    Full Text Available Self-organization during friction in complex surface engineered tribosystems is investigated. The probability of self-organization in these complex tribosystems is studied on the basis of the theoretical concepts of irreversible thermodynamics. It is shown that a higher number of interrelated processes within the system result in an increased probability of self-organization. The results of this thermodynamic model are confirmed by the investigation of the wear performance of a novel Ti0.2Al0.55Cr0.2Si0.03Y0.02N/Ti0.25Al0.65Cr0.1N (PVD coating with complex nano-multilayered structure under extreme tribological conditions of dry high-speed end milling of hardened H13 tool steel.

  3. A concept of vehicle-based collision prevention in self-organized railway systems (SOG); Konzept zur fahrzeuggestuetzten Kollisionsvermeidung im selbstorganisierenden Gueterverkehr (SOG)

    Energy Technology Data Exchange (ETDEWEB)

    Vallee, H.

    2002-07-01

    Self-organizing vehicles are a revolution in railway transport: They find their own way in the available railway network, and they detect and solve conflicts encountered on the way. - The report presents the algorithms for conflict identification and solution. Conflicts are mapped according to the number of conflict sites, the travelling direction of the vehicles in the conflict sites, and particularities of the programmed destinations. Solution schemes are presented for each type of conflict. The applicability of the algorithms is illustrated by a simulation and in trial operation of real vehicles. [German] Selbstorganisierend verkehrende Fahrzeuge revolutionieren den Schienengueterverkehr. Sie suchen ihren Fahrweg durch das ihnen zur Verfuegung stehende Gleisnetz selbst. Sie erkennen und loesen Konflikte innerhalb der von ihnen gewaehlten Fahrwege. - In dieser Arbeit werden die Algorithmen fuer die Konflikterkennung und Konfliktloesung beschrieben. Konflikte werden in Konfliktarten eingeteilt. Kriterien dafuer sind die Anzahl der Konfliktorte, die Fahrtrichtungen der Fahrzeuge innerhalb der Konfliktorte sowie Besonderheiten der programmierten Zielorte. Fuer jede Konfliktart werden schematisierte Loesungen angegeben. Die Tauglichkeit der Algorithmen wurde in einer Simulation und einem Testbetrieb mit realen Fahrzeugen gezeigt. (orig.)

  4. Bacillus subtilis MreB orthologs self-organize into filamentous structures underneath the cell membrane in a heterologous cell system.

    Directory of Open Access Journals (Sweden)

    Felix Dempwolff

    Full Text Available Actin-like bacterial cytoskeletal element MreB has been shown to be essential for the maintenance of rod cell shape in many bacteria. MreB forms rapidly remodelling helical filaments underneath the cell membrane in Bacillus subtilis and in other bacterial cells, and co-localizes with its two paralogs, Mbl and MreBH. We show that MreB localizes as dynamic bundles of filaments underneath the cell membrane in Drosophila S2 Schneider cells, which become highly stable when the ATPase motif in MreB is modified. In agreement with ATP-dependent filament formation, the depletion of ATP in the cells lead to rapid dissociation of MreB filaments. Extended induction of MreB resulted in the formation of membrane protrusions, showing that like actin, MreB can exert force against the cell membrane. Mbl also formed membrane associated filaments, while MreBH formed filaments within the cytosol. When co-expressed, MreB, Mbl and MreBH built up mixed filaments underneath the cell membrane. Membrane protein RodZ localized to endosomes in S2 cells, but localized to the cell membrane when co-expressed with Mbl, showing that bacterial MreB/Mbl structures can recruit a protein to the cell membrane. Thus, MreB paralogs form a self-organizing and dynamic filamentous scaffold underneath the membrane that is able to recruit other proteins to the cell surface.

  5. Bacillus subtilis MreB orthologs self-organize into filamentous structures underneath the cell membrane in a heterologous cell system.

    Science.gov (United States)

    Dempwolff, Felix; Reimold, Christian; Reth, Michael; Graumann, Peter L

    2011-01-01

    Actin-like bacterial cytoskeletal element MreB has been shown to be essential for the maintenance of rod cell shape in many bacteria. MreB forms rapidly remodelling helical filaments underneath the cell membrane in Bacillus subtilis and in other bacterial cells, and co-localizes with its two paralogs, Mbl and MreBH. We show that MreB localizes as dynamic bundles of filaments underneath the cell membrane in Drosophila S2 Schneider cells, which become highly stable when the ATPase motif in MreB is modified. In agreement with ATP-dependent filament formation, the depletion of ATP in the cells lead to rapid dissociation of MreB filaments. Extended induction of MreB resulted in the formation of membrane protrusions, showing that like actin, MreB can exert force against the cell membrane. Mbl also formed membrane associated filaments, while MreBH formed filaments within the cytosol. When co-expressed, MreB, Mbl and MreBH built up mixed filaments underneath the cell membrane. Membrane protein RodZ localized to endosomes in S2 cells, but localized to the cell membrane when co-expressed with Mbl, showing that bacterial MreB/Mbl structures can recruit a protein to the cell membrane. Thus, MreB paralogs form a self-organizing and dynamic filamentous scaffold underneath the membrane that is able to recruit other proteins to the cell surface.

  6. Anomalous relaxation and self-organization in nonequilibrium processes

    International Nuclear Information System (INIS)

    Fatkullin, Ibrahim; Kladko, Konstantin; Mitkov, Igor; Bishop, A. R.

    2001-01-01

    We study thermal relaxation in ordered arrays of coupled nonlinear elements with external driving. We find that our model exhibits dynamic self-organization manifested in a universal stretched-exponential form of relaxation. We identify two types of self-organization, cooperative and anticooperative, which lead to fast and slow relaxation, respectively. We give a qualitative explanation for the behavior of the stretched exponent in different parameter ranges. We emphasize that this is a system exhibiting stretched-exponential relaxation without explicit disorder or frustration

  7. 5G heterogeneous networks self-organizing and optimization

    CERN Document Server

    Rong, Bo; Kadoch, Michel; Sun, Songlin; Li, Wenjing

    2016-01-01

    This SpringerBrief provides state-of-the-art technical reviews on self-organizing and optimization in 5G systems. It covers the latest research results from physical-layer channel modeling to software defined network (SDN) architecture. This book focuses on the cutting-edge wireless technologies such as heterogeneous networks (HetNets), self-organizing network (SON), smart low power node (LPN), 3D-MIMO, and more. It will help researchers from both the academic and industrial worlds to better understand the technical momentum of 5G key technologies.

  8. Complexity in plasma. A grand view of self-organization

    International Nuclear Information System (INIS)

    Sato, Tetsuya.

    1994-11-01

    The central theme of the Complexity is the inquest of the creation of ordered structure in nature. Extensive computer simulations on plasmas have revealed that self-organization is governed by the three key processes, i.e. energy pumping, entropy expulsion and nonlinearity. A system exhibits characteristically different self-organization, depending on whether the energy pumping is instantaneous or continuous, or whether the produced entropy is expulsed or reserved. The nonlinearity acts to bring a nonequilibrium state into a bifurcation, thus resulting in a new structure along with an anomalous entropy production. (author)

  9. Self-Organization in Coupled Map Scale-Free Networks

    International Nuclear Information System (INIS)

    Xiao-Ming, Liang; Zong-Hua, Liu; Hua-Ping, Lü

    2008-01-01

    We study the self-organization of phase synchronization in coupled map scale-free networks with chaotic logistic map at each node and find that a variety of ordered spatiotemporal patterns emerge spontaneously in a regime of coupling strength. These ordered behaviours will change with the increase of the average links and are robust to both the system size and parameter mismatch. A heuristic theory is given to explain the mechanism of self-organization and to figure out the regime of coupling for the ordered spatiotemporal patterns

  10. Eco-evolutionary feedbacks in self-organized ecosystems

    NARCIS (Netherlands)

    de Jager, M.

    2015-01-01

    Spatial patterns in natural systems may appear amazingly complex. Yet, they can often be explained by a few simple rules. In self-organized ecosystems, complex spatial patterns at the ecosystem scale arise as the consequence of actions of and interactions between organisms at a local scale.

  11. Growing hierarchical probabilistic self-organizing graphs.

    Science.gov (United States)

    López-Rubio, Ezequiel; Palomo, Esteban José

    2011-07-01

    Since the introduction of the growing hierarchical self-organizing map, much work has been done on self-organizing neural models with a dynamic structure. These models allow adjusting the layers of the model to the features of the input dataset. Here we propose a new self-organizing model which is based on a probabilistic mixture of multivariate Gaussian components. The learning rule is derived from the stochastic approximation framework, and a probabilistic criterion is used to control the growth of the model. Moreover, the model is able to adapt to the topology of each layer, so that a hierarchy of dynamic graphs is built. This overcomes the limitations of the self-organizing maps with a fixed topology, and gives rise to a faithful visualization method for high-dimensional data.

  12. Self-organized topology of recurrence-based complex networks

    International Nuclear Information System (INIS)

    Yang, Hui; Liu, Gang

    2013-01-01

    With the rapid technological advancement, network is almost everywhere in our daily life. Network theory leads to a new way to investigate the dynamics of complex systems. As a result, many methods are proposed to construct a network from nonlinear time series, including the partition of state space, visibility graph, nearest neighbors, and recurrence approaches. However, most previous works focus on deriving the adjacency matrix to represent the complex network and extract new network-theoretic measures. Although the adjacency matrix provides connectivity information of nodes and edges, the network geometry can take variable forms. The research objective of this article is to develop a self-organizing approach to derive the steady geometric structure of a network from the adjacency matrix. We simulate the recurrence network as a physical system by treating the edges as springs and the nodes as electrically charged particles. Then, force-directed algorithms are developed to automatically organize the network geometry by minimizing the system energy. Further, a set of experiments were designed to investigate important factors (i.e., dynamical systems, network construction methods, force-model parameter, nonhomogeneous distribution) affecting this self-organizing process. Interestingly, experimental results show that the self-organized geometry recovers the attractor of a dynamical system that produced the adjacency matrix. This research addresses a question, i.e., “what is the self-organizing geometry of a recurrence network?” and provides a new way to reproduce the attractor or time series from the recurrence plot. As a result, novel network-theoretic measures (e.g., average path length and proximity ratio) can be achieved based on actual node-to-node distances in the self-organized network topology. The paper brings the physical models into the recurrence analysis and discloses the spatial geometry of recurrence networks

  13. Self-organized Segregation on the Grid

    Science.gov (United States)

    Omidvar, Hamed; Franceschetti, Massimo

    2018-02-01

    We consider an agent-based model with exponentially distributed waiting times in which two types of agents interact locally over a graph, and based on this interaction and on the value of a common intolerance threshold τ , decide whether to change their types. This is equivalent to a zero-temperature ising model with Glauber dynamics, an asynchronous cellular automaton with extended Moore neighborhoods, or a Schelling model of self-organized segregation in an open system, and has applications in the analysis of social and biological networks, and spin glasses systems. Some rigorous results were recently obtained in the theoretical computer science literature, and this work provides several extensions. We enlarge the intolerance interval leading to the expected formation of large segregated regions of agents of a single type from the known size ɛ >0 to size ≈ 0.134. Namely, we show that for 0.433sites can be observed within any sufficiently large region of the occupied percolation cluster. The exponential bounds that we provide also imply that complete segregation, where agents of a single type cover the whole grid, does not occur with high probability for p=1/2 and the range of intolerance considered.

  14. Toward an integrated theory of spatial morphology and resilient urban systems

    Directory of Open Access Journals (Sweden)

    Lars Marcus

    2014-12-01

    Full Text Available We take the first step in the development of a new field of research with the aim of merging spatial morphology and resilience science. This involves a revisiting and reunderstanding of the meaning of sustainable urban form. We briefly describe the fields of resilience science and spatial morphology. Drawing on a selected set of propositions in both fields, we put urban form in the context of the adaptive renewal cycle, a dynamic framework model used in resilience science to capture the dynamics of complex adaptive systems, of which urban systems are prime examples. We discuss the insights generated in this endeavor, dealing with some key morphological aspects in relation to four key attributes of resilience, i.e., "change," "diversity," "self-organization," and "learning." We discuss and relate these to urban form and other social variables, with special attention paid to the "backloop phase" of the adaptive renewal cycle. We conclude by postulating ways in which resilience thinking could contribute to the development of a new research frontier for addressing designs for resilient urban social-ecological systems, and end by proposing three strategic areas of research in such a field.

  15. 10th Workshop on Self-Organizing Maps

    CERN Document Server

    Schleif, Frank-Michael; Kaden, Marika; Lange, Mandy

    2014-01-01

    The book collects the scientific contributions presented at the 10th Workshop on Self-Organizing Maps (WSOM 2014) held at the University of Applied Sciences Mittweida, Mittweida (Germany, Saxony), on July 2–4, 2014. Starting with the first WSOM-workshop 1997 in Helsinki this workshop focuses on newest results in the field of supervised and unsupervised vector quantization like self-organizing maps for data mining and data classification.   This 10th WSOM brought together more than 50 researchers, experts and practitioners in the beautiful small town Mittweida in Saxony (Germany) nearby the mountains Erzgebirge to discuss new developments in the field of unsupervised self-organizing vector quantization systems and learning vector quantization approaches for classification. The book contains the accepted papers of the workshop after a careful review process as well as summaries of the invited talks.   Among these book chapters there are excellent examples of the use of self-organizing maps in agriculture, ...

  16. Non-Taylor magnetohydrodynamic self-organization

    International Nuclear Information System (INIS)

    Zhu, Shao-ping; Horiuchi, Ritoku; Sato, Tetsuya.

    1994-10-01

    A self-organization process in a plasma with a finite pressure is investigated by means of a three-dimensional magnetohydrodynamic simulation. It is demonstrated that a non-Taylor finite β self-organized state is realized in which a perpendicular component of the electric current is generated and the force-free(parallel) current decreases until they reach to almost the same level. The self-organized state is described by an MHD force-balance relation, namely, j perpendicular = B x ∇p/B·B and j parallel = μB where μ is not a constant, and the pressure structure resembles the structure of the toroidal magnetic field intensity. Unless an anomalous perpendicular thermal conduction arises, the plasma cannot relax to a Taylor state but to a non-Taylor (non-force-free) self-organized state. This state becomes more prominent for a weaker resistivity condition. The non-Taylor state has a rather universal property, for example, independence of the initial β value. Another remarkable finding is that the Taylor's conjecture of helicity conservation is, in a strict sense, not valid. The helicity dissipation occurs and its rate slows down critically in accordance with the stepwise relaxation of the magnetic energy. It is confirmed that the driven magnetic reconnection caused by the nonlinearly excited plasma kink flows plays the leading role in all of these key features of the non-Taylor self-organization. (author)

  17. Risk-based fault detection using Self-Organizing Map

    International Nuclear Information System (INIS)

    Yu, Hongyang; Khan, Faisal; Garaniya, Vikram

    2015-01-01

    The complexity of modern systems is increasing rapidly and the dominating relationships among system variables have become highly non-linear. This results in difficulty in the identification of a system's operating states. In turn, this difficulty affects the sensitivity of fault detection and imposes a challenge on ensuring the safety of operation. In recent years, Self-Organizing Maps has gained popularity in system monitoring as a robust non-linear dimensionality reduction tool. Self-Organizing Map is able to capture non-linear variations of the system. Therefore, it is sensitive to the change of a system's states leading to early detection of fault. In this paper, a new approach based on Self-Organizing Map is proposed to detect and assess the risk of fault. In addition, probabilistic analysis is applied to characterize the risk of fault into different levels according to the hazard potential to enable a refined monitoring of the system. The proposed approach is applied on two experimental systems. The results from both systems have shown high sensitivity of the proposed approach in detecting and identifying the root cause of faults. The refined monitoring facilitates the determination of the risk of fault and early deployment of remedial actions and safety measures to minimize the potential impact of fault. - Highlights: • A new approach based on Self-Organizing Map is proposed to detect faults. • Integration of fault detection with risk assessment methodology. • Fault risk characterization into different levels to enable focused system monitoring

  18. Information and Self-Organization

    Directory of Open Access Journals (Sweden)

    Hermann Haken

    2016-12-01

    Full Text Available The process of “self-organization” takes place in open and complex systems that acquire spatio-temporal or functional structures without specific ordering instructions from the outside. [...

  19. The Danish urban system pre-1800

    DEFF Research Database (Denmark)

    Christensen, Søren Bitsch; Mikkelsen, Jørgen

    2006-01-01

    , religious and military centres. From 1200 to 1350 Denmark, similar to the German area, underwent considerable urbanization; a large number of market towns were created, and in contrast to the older ones they were mercantile towns. Denmark thus clearly became the most urbanized country in Scandinavia....... As Copenhagen grew in the sixteenth and seventeenth centuries, the urban system decisively changed its character in the direction of a primate system. The characteristics of the primate system are particularly distinct within the boundaries of the Kingdom of Denmark, but less pronounced if the entire monarchy...... is included in the period in which Denmark was a conglomerate state. The institutional conditions must in general be attributed considerable importance in explaining Danish urban development. Thus, Denmark is one of the countries where town privileges were of great significance until the middle...

  20. Singularity spectrum of self-organized criticality

    International Nuclear Information System (INIS)

    Canessa, E.

    1992-10-01

    I introduce a simple continuous probability theory based on the Ginzburg-Landau equation that provides for the first time a common analytical basis to relate and describe the main features of two seemingly different phenomena of condensed-matter physics, namely self-organized criticality and multifractality. Numerical support is given by a comparison with reported simulation data. Within the theory the origin of self-organized critical phenomena is analysed in terms of a nonlinear singularity spectrum different form the typical convex shape due to multifractal measures. (author). 29 refs, 5 figs

  1. Natural hazards and self-organized criticality

    International Nuclear Information System (INIS)

    Krenn, R.

    2012-01-01

    Several natural hazards exhibit power-law behavior on their frequency-size distributions. Self-organized criticality has become a promising candidate that could offer a more in-depth understanding of the origin of temporal and spatial scaling in dissipative nonequilibrium systems. The outcomes of this thesis are presented in three scientific papers followed by a concluding summary and an appendix.In paper (A) we present a semi-phenomenological approach to explain the complex scaling behavior of the Drossel-Schwabl forest-fire model (DS-FFM) in two dimensions. We derive the scaling exponent solely from the scaling exponent of the clusters' accessible perimeter. Furthermore, the unusual transition to an exponential decay is explained both qualitatively and quantitatively. The exponential decay itself could be reproduced at least qualitatively. In paper (B) we extend the DS-FFM towards anthropogenic ignition factors. The main outcomes are an increase of the scaling exponent with decreasing lightning probability as well as a splitting of the partial frequency-size distributions of lightning induced and man made fires. Lightning is identified as the dominant mechanism in the regime of the largest fires. The results could be validated through an analysis of the Canadian Large Fire Database.In paper (C) we obtain an almost complete theory of the Olami-Feder-Christensen (OFC) model's complex spatio-temporal behavior. Synchronization pushes the system towards a critical state and generates the Gutenberg-Richter law. Desynchronization prevents the system from becoming overcritical and generates foreshocks and aftershocks. Our approach also provides a simple explanation of Omori's law. Beyond this, it explains the phenomena of foreshock migration and aftershock diffusion and the occurrence of large earthquakes without any foreshocks. A novel integer algorithm for the numerics is presented in appendix (A).(author) [de

  2. Systemic Resilience of Complex Urban Systems

    Directory of Open Access Journals (Sweden)

    Serge Salat

    2012-07-01

    Full Text Available Two key paradigms emerge out of the variety of urban forms: certain cities resemble trees, others leaves. The structural difference between a tree and a leaf is huge: one is open, the other closed. Trees are entirely disconnected on a given scale: even if two twigs are spatially close, if they do not belong to the same branch, to go from one to the other implies moving down and then up all the hierarchy of branches.  Leaves on the contrary are entirely connected on intermediary scales. The veins of a leaf are disconnected on the two larger scales but entirely connected on the two or three following intermediary scales before presenting tiny tree-like structures on the finest capillary scales. Deltas are leaves not trees. Neither galaxies nor whirlpools are trees. We will see in this paper that historical cities, like leaves, deltas, galaxies, lungs, brains and vein systems are all fractal structures, multiply connected and complex on all scales. These structures display the same degree of complexity and connectivity, regardless of the magnification scale on which we observe them. We say that these structures are scale free. Mathematical fractal forms are often generated recursively by applying again and again the same generator to an initiator. The iteration creates an arborescence. But scale free structure is not synonymous with a recursive tree-like structure. The fractal structure of the leaf is much more complex than that of the tree by its multiconnectivity on three or more intermediary levels. In contrast, trees in the virgin forest, even when they seem to be entangled, horizontal, and rhizomic, have branches that are not interconnected to form a lattice. As we will see, the history of urban planning has evolved from leaf-like to tree-like patterns, with a consequent loss of efficiency and resilience. Indeed, in a closed foliar path structure, the formation of cycles enables internal complexification and flow fluctuations due to the

  3. Guided self-organization inception

    CERN Document Server

    2014-01-01

    Is it possible to guide the process of self-organisation towards specific patterns and outcomes?  Wouldn’t this be self-contradictory?   After all, a self-organising process assumes a transition into a more organised form, or towards a more structured functionality, in the absence of centralised control.  Then how can we place the guiding elements so that they do not override rich choices potentially discoverable by an uncontrolled process?  This book presents different approaches to resolving this paradox.  In doing so, the presented studies address a broad range of phenomena, ranging from autopoietic systems to morphological computation, and from small-world networks to information cascades in swarms.  A large variety of methods is employed, from spontaneous symmetry breaking to information dynamics to evolutionary algorithms, creating a rich spectrum reflecting this emerging field. Demonstrating several foundational theories and frameworks, as well as innovative practical implementations, Guided S...

  4. Self-organizing sensing and actuation for automatic control

    Science.gov (United States)

    Cheng, George Shu-Xing

    2017-07-04

    A Self-Organizing Process Control Architecture is introduced with a Sensing Layer, Control Layer, Actuation Layer, Process Layer, as well as Self-Organizing Sensors (SOS) and Self-Organizing Actuators (SOA). A Self-Organizing Sensor for a process variable with one or multiple input variables is disclosed. An artificial neural network (ANN) based dynamic modeling mechanism as part of the Self-Organizing Sensor is described. As a case example, a Self-Organizing Soft-Sensor for CFB Boiler Bed Height is presented. Also provided is a method to develop a Self-Organizing Sensor.

  5. How nature works the science of self-organized criticality

    CERN Document Server

    Bak, Per

    1996-01-01

    This is an acclaimed book intended for the general reader who is interested in science. The author is a physicist who is well-known for his development of the property called "self-organized criticality", a property or phenomenon that lies at the heart of large dynamical systems. It can be used to analyse systems that are complicated, and which are part of the new science of complexity. It is a unifying concept that can be used to study phenomena in fields as diverse as economics, astronomy, the earth sciences, and physics. The author discusses his discovery of self-organized criticality; its relation to the world of classical physics; computer simulations and experiments which aid scientists' understanding of the property; and the relation of the subject to popular areas such as fractal geometry and power laws; cellular automata, and a wide range of practical applications.

  6. Self-organized critical pinball machine

    DEFF Research Database (Denmark)

    Flyvbjerg, H.

    2004-01-01

    The nature of self-organized criticality (SOC) is pin-pointed with a simple mechanical model: a pinball machine. Its phase space is fully parameterized by two integer variables, one describing the state of an on-going game, the other describing the state of the machine. This is the simplest...

  7. Self-organized criticality in fragmenting

    DEFF Research Database (Denmark)

    Oddershede, L.; Dimon, P.; Bohr, J.

    1993-01-01

    The measured mass distributions of fragments from 26 fractured objects of gypsum, soap, stearic paraffin, and potato show evidence of obeying scaling laws; this suggests the possibility of self-organized criticality in fragmenting. The probability of finding a fragment scales inversely to a power...

  8. Self-Organized Criticality and $1/f$ Noise in Traffic

    OpenAIRE

    Paczuski, Maya; Nagel, Kai

    1996-01-01

    Phantom traffic jams may emerge ``out of nowhere'' from small fluctuations rather than being triggered by large, exceptional events. We show how phantom jams arise in a model of single lane highway traffic, which mimics human driving behavior. Surprisingly, the optimal state of highest efficiency, with the largest throughput, is a critical state with traffic jams of all sizes. We demonstrate that open systems self-organize to the most efficient state. In the model we study, this critical stat...

  9. Self-organization analysis for a nonlocal convective Fisher equation

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, J.A.R. da [Instituto de Fisica, Universidade de Brasilia, 70919-970 Brasilia DF (Brazil); International Center for Condensed Matter Physics, CP 04513, 70919-970 Brasilia DF (Brazil); Penna, A.L.A. [Instituto de Fisica, Universidade de Brasilia, 70919-970 Brasilia DF (Brazil); International Center for Condensed Matter Physics, CP 04513, 70919-970 Brasilia DF (Brazil)], E-mail: penna.andre@gmail.com; Vainstein, M.H. [Instituto de Fisica, Universidade de Brasilia, 70919-970 Brasilia DF (Brazil); International Center for Condensed Matter Physics, CP 04513, 70919-970 Brasilia DF (Brazil); Morgado, R. [International Center for Condensed Matter Physics, CP 04513, 70919-970 Brasilia DF (Brazil); Departamento de Matematica, Universidade de Brasilia, 70910-900 Brasilia DF (Brazil); Oliveira, F.A. [Instituto de Fisica, Universidade de Brasilia, 70919-970 Brasilia DF (Brazil); International Center for Condensed Matter Physics, CP 04513, 70919-970 Brasilia DF (Brazil)

    2009-02-02

    Using both an analytical method and a numerical approach we have investigated pattern formation for a nonlocal convective Fisher equation with constant and spatial velocity fields. We analyze the limits of the influence function due to nonlocal interaction and we obtain the phase diagram of critical velocities v{sub c} as function of the width {mu} of the influence function, which characterize the self-organization of a finite system.

  10. Self-organization via active exploration in robotic applications

    Science.gov (United States)

    Ogmen, H.; Prakash, R. V.

    1992-01-01

    We describe a neural network based robotic system. Unlike traditional robotic systems, our approach focussed on non-stationary problems. We indicate that self-organization capability is necessary for any system to operate successfully in a non-stationary environment. We suggest that self-organization should be based on an active exploration process. We investigated neural architectures having novelty sensitivity, selective attention, reinforcement learning, habit formation, flexible criteria categorization properties and analyzed the resulting behavior (consisting of an intelligent initiation of exploration) by computer simulations. While various computer vision researchers acknowledged recently the importance of active processes (Swain and Stricker, 1991), the proposed approaches within the new framework still suffer from a lack of self-organization (Aloimonos and Bandyopadhyay, 1987; Bajcsy, 1988). A self-organizing, neural network based robot (MAVIN) has been recently proposed (Baloch and Waxman, 1991). This robot has the capability of position, size rotation invariant pattern categorization, recognition and pavlovian conditioning. Our robot does not have initially invariant processing properties. The reason for this is the emphasis we put on active exploration. We maintain the point of view that such invariant properties emerge from an internalization of exploratory sensory-motor activity. Rather than coding the equilibria of such mental capabilities, we are seeking to capture its dynamics to understand on the one hand how the emergence of such invariances is possible and on the other hand the dynamics that lead to these invariances. The second point is crucial for an adaptive robot to acquire new invariances in non-stationary environments, as demonstrated by the inverting glass experiments of Helmholtz. We will introduce Pavlovian conditioning circuits in our future work for the precise objective of achieving the generation, coordination, and internalization

  11. Systems biology and the origins of life? part II. Are biochemical networks possible ancestors of living systems? networks of catalysed chemical reactions: non-equilibrium, self-organization and evolution.

    Science.gov (United States)

    Ricard, Jacques

    2010-01-01

    The present article discusses the possibility that catalysed chemical networks can evolve. Even simple enzyme-catalysed chemical reactions can display this property. The example studied is that of a two-substrate proteinoid, or enzyme, reaction displaying random binding of its substrates A and B. The fundamental property of such a system is to display either emergence or integration depending on the respective values of the probabilities that the enzyme has bound one of its substrate regardless it has bound the other substrate, or, specifically, after it has bound the other substrate. There is emergence of information if p(A)>p(AB) and p(B)>p(BA). Conversely, if p(A)equilibrium. Moreover, in such systems, emergence results in an increase of the energy level of the ternary EAB complex that becomes closer to the transition state of the reaction, thus leading to the enhancement of catalysis. Hence a drift from quasi-equilibrium is, to a large extent, responsible for the production of information and enhancement of catalysis. Non-equilibrium of these simple systems must be an important aspect that leads to both self-organization and evolutionary processes. These conclusions can be extended to networks of catalysed chemical reactions. Such networks are, in fact, networks of networks, viz. meta-networks. In this formal representation, nodes are chemical reactions catalysed by poorly specific proteinoids, and links can be identified to the transport of metabolites from proteinoid to proteinoid. The concepts of integration and emergence can be applied to such situations and can be used to define the identity of these networks and therefore their evolution. Defined as open non-equilibrium structures, such biochemical networks possess two remarkable properties: (1) the probability of occurrence of their nodes is dependant upon the input and output of matter in, and from, the system and (2) the probability of occurrence of the nodes is strictly linked to their degree of

  12. Self-organizing periodicity in development: organ positioning in plants.

    Science.gov (United States)

    Bhatia, Neha; Heisler, Marcus G

    2018-02-08

    Periodic patterns during development often occur spontaneously through a process of self-organization. While reaction-diffusion mechanisms are often invoked, other types of mechanisms that involve cell-cell interactions and mechanical buckling have also been identified. Phyllotaxis, or the positioning of plant organs, has emerged as an excellent model system to study the self-organization of periodic patterns. At the macro scale, the regular spacing of organs on the growing plant shoot gives rise to the typical spiral and whorled arrangements of plant organs found in nature. In turn, this spacing relies on complex patterns of cell polarity that involve feedback between a signaling molecule - the plant hormone auxin - and its polar, cell-to-cell transport. Here, we review recent progress in understanding phyllotaxis and plant cell polarity and highlight the development of new tools that can help address the remaining gaps in our understanding. © 2018. Published by The Company of Biologists Ltd.

  13. The Consistent Support System in The Society for Lifelong Sports : From a View Point of Self-Organization of Sports Club and Support

    OpenAIRE

    長岡, 雅美; 赤松, 喜久; Masami, Nagaoka; Yoshihisa, Akamatsu

    2008-01-01

    The purpose of this study is to clarify the concept of Guidance and Support on community sports and to specify the directionality of organization and support for achievement of the sports society through life. The authors have stressed that it is necessary for achievement of the society for longlife sports,to cooperate with other groups and to construct a consistent support system. This study is also to explore the condition of community sports club management through analyzing the Japan Juni...

  14. Self-organization at the frictional interface for green tribology.

    Science.gov (United States)

    Nosonovsky, Michael

    2010-10-28

    Despite the fact that self-organization during friction has received relatively little attention from tribologists so far, it has the potential for the creation of self-healing and self-lubricating materials, which are important for green or environment-friendly tribology. The principles of the thermodynamics of irreversible processes and of the nonlinear theory of dynamical systems are used to investigate the formation of spatial and temporal structures during friction. The transition to the self-organized state with low friction and wear occurs through destabilization of steady-state (stationary) sliding. The criterion for destabilization is formulated and several examples are discussed: the formation of a protective film, microtopography evolution and slip waves. The pattern formation may involve self-organized criticality and reaction-diffusion systems. A special self-healing mechanism may be embedded into the material by coupling the corresponding required forces. The analysis provides the structure-property relationship, which can be applied for the design optimization of composite self-lubricating and self-healing materials for various ecologically friendly applications and green tribology.

  15. Innovative Mechanism of Rural Organization Based on Self-Organization

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The paper analyzes the basic situation of the formation of innovative rural organizations with the form of self-organization;reveals the features of self-organization,including the four aspects of openness of rural organization,innovation of rural organization far away from equilibrium,the non-linear response mechanism of rural organization innovation and the random rise and fall of rural organization innovation.The evolution mechanism of rural organization innovation is revealed according to the growth stage,the ideal stage,the decline and the fall stage.The paper probes into the basic restriction mechanism of the self-organization evaluation of rural organization from three aspects,including target recognition,path dependence and knowledge sharing.The basic measures on cultivating the innovative mechanism of rural organization are put forward.Firstly,constructing the dissipative structure of rural organization innovation;secondly,cultivating the dynamic study capability of rural organization innovation system;thirdly,selecting the step-by-step evolution strategy of rural organization innovation system.

  16. Ageing as a price of cooperation and complexity: self-organization of complex systems causes the gradual deterioration of constituent networks.

    Science.gov (United States)

    Kiss, Huba J M; Mihalik, Agoston; Nánási, Tibor; Ory, Bálint; Spiró, Zoltán; Soti, Csaba; Csermely, Peter

    2009-06-01

    The network concept is increasingly used for the description of complex systems. Here, we summarize key aspects of the evolvability and robustness of the hierarchical network set of macromolecules, cells, organisms and ecosystems. Listing the costs and benefits of cooperation as a necessary behaviour to build this network hierarchy, we outline the major hypothesis of the paper: the emergence of hierarchical complexity needs cooperation leading to the ageing (i.e. gradual deterioration) of the constituent networks. A stable environment develops cooperation leading to over-optimization, and forming an 'always-old' network, which accumulates damage, and dies in an apoptosis-like process. A rapidly changing environment develops competition forming a 'forever-young' network, which may suffer an occasional over-perturbation exhausting system resources, and causing death in a necrosis-like process. Giving a number of examples we demonstrate how cooperation evokes the gradual accumulation of damage typical to ageing. Finally, we show how various forms of cooperation and consequent ageing emerge as key elements in all major steps of evolution from the formation of protocells to the establishment of the globalized, modern human society.

  17. Environmental sustainability assessment of urban systems applying coupled urban metabolism and life cycle assessment

    DEFF Research Database (Denmark)

    Birkved, Morten; Goldstein, Benjamin Paul

    2013-01-01

    environmental sustainability of large urban systems by relating the environmental sustainability performance of urban systems with global environmental burden boundaries quantifying pollution thresholds beyond which performance of global ecosystems services may be detrimentally affected....

  18. Study on self organized criticality of China power grid blackouts

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xingyong; Zhang, Xiubin; He, Bin [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

    2009-03-15

    Based on the complex system theory and the concept of self organized criticality (SOC) theory, the mechanism of China power grid blackout is studied by analyzing the blackout data in the China power system from 1981 to 2002. The probability distribution functions of various measures of blackout size have a power tail. The analysis of scaled window variance and rescaled range statistics of the time series show moderate long time correlations. The blackout data seem consistent with SOC; the results obtained show that SOC dynamics may play an important role in the dynamics of power systems blackouts. It would be possible to propose novel approaches for understanding and controlling power systems blackouts. (author)

  19. Study on self organized criticality of China power grid blackouts

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Xingyong [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)], E-mail: zhaoxingyong@sjtu.edu.cn; Zhang Xiubin; He Bin [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

    2009-03-15

    Based on the complex system theory and the concept of self organized criticality (SOC) theory, the mechanism of China power grid blackout is studied by analyzing the blackout data in the China power system from 1981 to 2002. The probability distribution functions of various measures of blackout size have a power tail. The analysis of scaled window variance and rescaled range statistics of the time series show moderate long time correlations. The blackout data seem consistent with SOC; the results obtained show that SOC dynamics may play an important role in the dynamics of power systems blackouts. It would be possible to propose novel approaches for understanding and controlling power systems blackouts.

  20. Self-organized computation with unreliable, memristive nanodevices

    International Nuclear Information System (INIS)

    Snider, G S

    2007-01-01

    Nanodevices have terrible properties for building Boolean logic systems: high defect rates, high variability, high death rates, drift, and (for the most part) only two terminals. Economical assembly requires that they be dynamical. We argue that strategies aimed at mitigating these limitations, such as defect avoidance/reconfiguration, or applying coding theory to circuit design, present severe scalability and reliability challenges. We instead propose to mitigate device shortcomings and exploit their dynamical character by building self-organizing, self-healing networks that implement massively parallel computations. The key idea is to exploit memristive nanodevice behavior to cheaply implement adaptive, recurrent networks, useful for complex pattern recognition problems. Pulse-based communication allows the designer to make trade-offs between power consumption and processing speed. Self-organization sidesteps the scalability issues of characterization, compilation and configuration. Network dynamics supplies a graceful response to device death. We present simulation results of such a network-a self-organized spatial filter array-that demonstrate its performance as a function of defects and device variation

  1. Self-organization of polymerizable bolaamphiphiles bearing diacetylene mesogenic group.

    Science.gov (United States)

    Yin, Shouchun; Song, Bo; Liu, Guanqing; Wang, Zhiqiang; Zhang, Xi

    2007-05-22

    We report herein the synthesis of a series of polymerizable bolaamphiphiles containing a diacetylene group and mesogenic unit and their self-organization behaviors in bulk and at interface. The polymerizable bolaamphiphiles are noted as DPDA-n, where n refers to the spacer length of alkyl chain. DPDA-10 with suitable spacer length can self-organize into stable cylindrical micellar nanostructures, and these nanostructures have preferred orientation regionally when adsorbed at the mica/water interface. It is confirmed that the micellar nanostructure of DPDA-10 can be polymerized both in the bulk solution and in the film by UV irradiation. The emission property of DPDA-10 after UV irradiation has been significantly enhanced in comparison to that before polymerization, which may be due to the extension of the conjugated system arising from the transformation of the diacetylene group into polydiacetylene upon polymerization. In addition, the self-organization of DPDA-n is dependent on the spacer length. DPDA-7 with a short spacer length forms an irregular flat sheet structure with many defects; DPDA-15 with a long spacer length forms rodlike micellar structures. Thus, this work may provide a new approach for designing and fabricating organic functional nanostructured materials.

  2. Self-organization in metal complexes

    International Nuclear Information System (INIS)

    Radecka-Paryzek, W.

    1999-01-01

    Inorganic self-organization involves the spontaneous generation of well-defined supramolecular architectures from metal ions and organic ligands. The basic concept of supramolecular chemistry is a molecular recognition. When the substrate are metal ions, recognition is expressed in the stability and selectivity of metal ion complexation by organic ligands and depends on the geometry of the ligand and on their binding sites that it contains. The combination of the geometric features of the ligand units and the coordination geometries of the metal ions provides very efficient tool for the synthesis of novel, intriguing and highly sophisticated species such as catenanes, box structures, double and triple helicates with a variety of interesting properties. The article will focus on the examples of inorganic self-organization involving the templating as a first step for the assembly of supramolecular structures of high complexity. (author)

  3. Self-organized critical neural networks

    International Nuclear Information System (INIS)

    Bornholdt, Stefan; Roehl, Torsten

    2003-01-01

    A mechanism for self-organization of the degree of connectivity in model neural networks is studied. Network connectivity is regulated locally on the basis of an order parameter of the global dynamics, which is estimated from an observable at the single synapse level. This principle is studied in a two-dimensional neural network with randomly wired asymmetric weights. In this class of networks, network connectivity is closely related to a phase transition between ordered and disordered dynamics. A slow topology change is imposed on the network through a local rewiring rule motivated by activity-dependent synaptic development: Neighbor neurons whose activity is correlated, on average develop a new connection while uncorrelated neighbors tend to disconnect. As a result, robust self-organization of the network towards the order disorder transition occurs. Convergence is independent of initial conditions, robust against thermal noise, and does not require fine tuning of parameters

  4. Eco-Polycentric Urban Systems: An Ecological Region Perspective for Network Cities

    Directory of Open Access Journals (Sweden)

    André Botequilha-Leitão

    2012-04-01

    Full Text Available The research presented in this paper is a work in progress. It provides linkages between the author’s earlier research under the sustainable land planning framework (SLP and emergent ideas and planning and design strategies, centered on the (landscape ecological dimension of cities’ sustainability. It reviews several concepts, paradigms, and metaphors that have been emerging during the last decade, which can contribute to expand our vision on city planning and design. Among other issues, city form—monocentric, polycentric, and diffused—is discussed. The hypothesis set forth is that cities can improve the pathway to sustainability by adopting intermediate, network urban forms such as polycentric urban systems (PUS under a broader vision (as compared to the current paradigm, to make way to urban ecological regions. It discusses how both the principles of SLP and those emergent ideas can contribute to integrate PUS with their functional hinterland, adopting an ecosystemic viewpoint of cities. It proposes to redirect the current dominant economic focus of PUS to include all of the other functions that are essential to urbanites, such as production (including the 3Rs, recreation, and ecology in a balanced way. Landscape ecology principles are combined with complexity science in order to deal with uncertainty to improve regional systems’ resilience. Cooperation in its multiple forms is seen as a fundamental social, but also economic process contributing to the urban network functioning, including its evolving capabilities for self-organization and adaptation.

  5. The Mammalian Cortex as a Self-Organizing Complex System: Multi-Scale Homeostatic Approaches to Criticality via Dynamical Balance of Inhibition against Excitation

    Science.gov (United States)

    Ng, Tony T.

    The mammalian cortex is a highly structured network of densely packed neurons that interact strongly with each other in very specific ways. Loosely speaking, neurons are cells that fire clicks at each other as a means of communication. Common sites of communication, known as synapses, are enabled by transmitter molecules released from presynaptic sender cells, which bind to receptors on postsynaptic receiver cells. There are two major classes of neurons - excitatory ones that prompt their downstream neighbors to fire spikes through depolarization, and inhibitory ones that suppress spike activity of their postsynaptic partners via hyperpolarization. Depolarization and hyperpolarization make membrane potential of a cell more positive and more negative, respectively. A sufficiently depolarized neuron fires a spike, which technically is called an action potential. In this thesis, we focus on the interplay between three of the cortex's most ubiquitous features and examine some of the consequences that their interactions have on cortical dynamics. One of the features, widespread projections between clusters of excitatory neurons, is topological. The two remaining features, homeostasis and balance between the amount of excitatory and inhibitory activity are dynamical. Here, homeostasis refers to the regulatory mechanism of individual cells or collections of cells that maintains constant levels of spike activity over time. Simply by varying the average homeostatic firing rate in clusters of excitatory neurons or by tuning the common homoeostatic rate of individual inhibitory neurons, we show via simulation that cluster-based activity bursts can exhibit critical dynamics and display power-law distributions with exponents that are consistent with those found in in vivo experiments of awake animals. Criticality is an idea that originated in statistical physics. At the critical point, activity levels of sites across an entire system, such as those of different cortical regions

  6. Workplace Accidents and Self-Organized Criticality

    OpenAIRE

    Mauro, John C.; Diehl, Brett; Marcellin, Richard F.; Vaughn, Daniel J.

    2018-01-01

    The occurrence of workplace accidents is described within the context of self-organized criticality, a theory from statistical physics that governs a wide range of phenomena across physics, biology, geosciences, economics, and the social sciences. Workplace accident data from the U.S. Bureau of Labor Statistics reveal a power-law relationship between the number of accidents and their severity as measured by the number of days lost from work. This power-law scaling is indicative of workplace a...

  7. Self-organization in circular shear layers

    DEFF Research Database (Denmark)

    Bergeron, K.; Coutsias, E.A.; Lynov, Jens-Peter

    1996-01-01

    Experiments on forced circular shear layers performed in both magnetized plasmas and in rotating fluids reveal qualitatively similar self-organization processes leading to the formation of patterns of coherent vortical structures with varying complexity. In this paper results are presented from...... both weakly nonlinear analysis and full numerical simulations that closely reproduce the experimental observations. Varying the Reynolds number leads to bifurcation sequences accompanied by topological changes in the distribution of the coherent structures as well as clear transitions in the total...

  8. Self-organized criticality in neural networks

    Science.gov (United States)

    Makarenkov, Vladimir I.; Kirillov, A. B.

    1991-08-01

    Possible mechanisms of creating different types of persistent states for informational processing are regarded. It is presented two origins of criticalities - self-organized and phase transition. A comparative analyses of their behavior is given. It is demonstrated that despite a likeness there are important differences. These differences can play a significant role to explain the physical issue of such highest functions of the brain as a short-term memory and attention. 1.

  9. Instantons in Self-Organizing Logic Gates

    Science.gov (United States)

    Bearden, Sean R. B.; Manukian, Haik; Traversa, Fabio L.; Di Ventra, Massimiliano

    2018-03-01

    Self-organizing logic is a recently suggested framework that allows the solution of Boolean truth tables "in reverse"; i.e., it is able to satisfy the logical proposition of gates regardless to which terminal(s) the truth value is assigned ("terminal-agnostic logic"). It can be realized if time nonlocality (memory) is present. A practical realization of self-organizing logic gates (SOLGs) can be done by combining circuit elements with and without memory. By employing one such realization, we show, numerically, that SOLGs exploit elementary instantons to reach equilibrium points. Instantons are classical trajectories of the nonlinear equations of motion describing SOLGs and connect topologically distinct critical points in the phase space. By linear analysis at those points, we show that these instantons connect the initial critical point of the dynamics, with at least one unstable direction, directly to the final fixed point. We also show that the memory content of these gates affects only the relaxation time to reach the logically consistent solution. Finally, we demonstrate, by solving the corresponding stochastic differential equations, that, since instantons connect critical points, noise and perturbations may change the instanton trajectory in the phase space but not the initial and final critical points. Therefore, even for extremely large noise levels, the gates self-organize to the correct solution. Our work provides a physical understanding of, and can serve as an inspiration for, models of bidirectional logic gates that are emerging as important tools in physics-inspired, unconventional computing.

  10. Search Techniques for Self-Organizing Systems

    Science.gov (United States)

    1975-07-01

    according to their associated function values. The classes need not have equal function value ranges (i.e., the . ................... "The Mucciardi- Gose ... Gose , "An Automatic Clustering Algorithm and Its !’ropertizs in High-Dimensional Spaces,’[ IFEE Trans. S s~tems, Man and Cybernetics, Vol. SMC-2

  11. Self-organizing energy-autonomous systems

    NARCIS (Netherlands)

    Liu, Q.

    2016-01-01

    With the rapid development of mobile technology, more and more devices connect to the Internet of Things (IoT). The management of such large-scale networks becomes a challenge. Firstly, a large number of heterogeneous devices are distributed over a wide area, leading to a variation of the

  12. Advances in applied self-organizing systems

    CERN Document Server

    Prokopenko, Mikhail

    2013-01-01

    This book is the perfect introduction for anyone wanting to create sophisticated Windows 8 apps for the first time.Assuming only a basic knowledge of HTML and CSS we'll walk you through the development process using C# and VB. The book will familiarize you with the tools you'll need to use in order to make the most of Windows' stunning new features. You'll discover how to take advantage of the built-in functionality to create high quality user experiences.

  13. Self-organization and oscillation of negatively charged dust particles in a 2-dimensional dusty plasma

    Energy Technology Data Exchange (ETDEWEB)

    Song, Y.L. [College of Science, China Agricultural University, Beijing 100083 (China); Huang, F., E-mail: huangfeng@cau.edu.cn [College of Science, China Agricultural University, Beijing 100083 (China); Chen, Z.Y., E-mail: chenzy@mail.buct.edu.cn [Department of Physics, Beijing University of Chemical Technology, Beijing 100029 (China); State Key Laboratory of Laser Propulsion & Application, Beijing 101416 (China); Liu, Y.H. [School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025 (China); Yu, M.Y. [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, D-44801 Bochum (Germany)

    2016-02-22

    Negatively charged dust particles immersed in 2-dimensional dusty plasma system are investigated by molecular dynamics simulations. The effects of the confinement potential and attraction interaction potential on dust particle self-organization are studied in detail and two typical dust particle distributions are obtained when the system reaches equilibrium. The average radial velocity (ARV), average radial force (ARF) and radial mean square displacement are employed to analyze the dust particles' dynamics. Both ARVs and ARFs exhibit oscillation behaviors when the simulation system reaches equilibrium state. The relationships between the oscillation and confinement potential and attraction potential are studied in this paper. The simulation results are qualitatively similar to experimental results. - Highlights: • Self-organization and oscillation of a 2-dimensional dusty plasma is investigated. • Effect of the confinement potential on dust self-organization and oscillation is given. • Effect of the attraction potential on dust self-organization and oscillation is studied.

  14. Self-organization and oscillation of negatively charged dust particles in a 2-dimensional dusty plasma

    International Nuclear Information System (INIS)

    Song, Y.L.; Huang, F.; Chen, Z.Y.; Liu, Y.H.; Yu, M.Y.

    2016-01-01

    Negatively charged dust particles immersed in 2-dimensional dusty plasma system are investigated by molecular dynamics simulations. The effects of the confinement potential and attraction interaction potential on dust particle self-organization are studied in detail and two typical dust particle distributions are obtained when the system reaches equilibrium. The average radial velocity (ARV), average radial force (ARF) and radial mean square displacement are employed to analyze the dust particles' dynamics. Both ARVs and ARFs exhibit oscillation behaviors when the simulation system reaches equilibrium state. The relationships between the oscillation and confinement potential and attraction potential are studied in this paper. The simulation results are qualitatively similar to experimental results. - Highlights: • Self-organization and oscillation of a 2-dimensional dusty plasma is investigated. • Effect of the confinement potential on dust self-organization and oscillation is given. • Effect of the attraction potential on dust self-organization and oscillation is studied.

  15. A New Era for Urban Modelling

    OpenAIRE

    Pumain , Denise

    1994-01-01

    International audience; In the last two decades, several interesting innovations have appeared in the field of urban research. New paradigms such as the dynamics of open systems, self-organization, synergetics, chaos, evolution, were recognized as conveying fruitful analogies for urban theory. New types of modeling were investigated, as sets of non-linear differential equations for spatial systems, cellular automata, multi-agents models, fractal growth, neural networks, evolutionary models… H...

  16. Pattern classification and recognition of invertebrate functional groups using self-organizing neural networks.

    Science.gov (United States)

    Zhang, WenJun

    2007-07-01

    Self-organizing neural networks can be used to mimic non-linear systems. The main objective of this study is to make pattern classification and recognition on sampling information using two self-organizing neural network models. Invertebrate functional groups sampled in the irrigated rice field were classified and recognized using one-dimensional self-organizing map and self-organizing competitive learning neural networks. Comparisons between neural network models, distance (similarity) measures, and number of neurons were conducted. The results showed that self-organizing map and self-organizing competitive learning neural network models were effective in pattern classification and recognition of sampling information. Overall the performance of one-dimensional self-organizing map neural network was better than self-organizing competitive learning neural network. The number of neurons could determine the number of classes in the classification. Different neural network models with various distance (similarity) measures yielded similar classifications. Some differences, dependent upon the specific network structure, would be found. The pattern of an unrecognized functional group was recognized with the self-organizing neural network. A relative consistent classification indicated that the following invertebrate functional groups, terrestrial blood sucker; terrestrial flyer; tourist (nonpredatory species with no known functional role other than as prey in ecosystem); gall former; collector (gather, deposit feeder); predator and parasitoid; leaf miner; idiobiont (acarine ectoparasitoid), were classified into the same group, and the following invertebrate functional groups, external plant feeder; terrestrial crawler, walker, jumper or hunter; neustonic (water surface) swimmer (semi-aquatic), were classified into another group. It was concluded that reliable conclusions could be drawn from comparisons of different neural network models that use different distance

  17. Understanding complex urban systems multidisciplinary approaches to modeling

    CERN Document Server

    Gurr, Jens; Schmidt, J

    2014-01-01

    Understanding Complex Urban Systems takes as its point of departure the insight that the challenges of global urbanization and the complexity of urban systems cannot be understood – let alone ‘managed’ – by sectoral and disciplinary approaches alone. But while there has recently been significant progress in broadening and refining the methodologies for the quantitative modeling of complex urban systems, in deepening the theoretical understanding of cities as complex systems, or in illuminating the implications for urban planning, there is still a lack of well-founded conceptual thinking on the methodological foundations and the strategies of modeling urban complexity across the disciplines. Bringing together experts from the fields of urban and spatial planning, ecology, urban geography, real estate analysis, organizational cybernetics, stochastic optimization, and literary studies, as well as specialists in various systems approaches and in transdisciplinary methodologies of urban analysis, the volum...

  18. Temporal, spatial and social patterens of self-organization within street sport

    DEFF Research Database (Denmark)

    Sand, Anne-Lene

    Due to an increased urbanization and digitalization self-organized practices are becoming a central way of doing sports among contemporary young people and adults in urban contexts. The aim of this presentation is to contribute with knowledge about what it means to be self-organized within street...... young people can re-define urban space themselves (Skelton and Valentine 2007). During a multi-sited fieldwork (Marcus 1995) I followed people in Denmark that value to be able to improvise in the way they organize their own street-sport practices through temporal, spatial and social practices. Street...... among young people and adults, in order to redefine and reconstruct future leisure organizations (Rojek 1995) and understand contemporary forms of street sport....

  19. Open innovation in urban energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, M. [Technische Universitaet Muenchen, TUM School of Management, Freising (Germany); Barth, V. [Carl von Ossietzky Universitaet Oldenburg, Ecological Economics, Oldenburg (Germany)

    2012-08-15

    Despite recent efforts, existing urban energy systems still hardly meet the demands of sustainable development or climate change. Meeting these targets thus will require innovations that use energy much more efficiently and emit far less greenhouse gases. These innovations need to be made on the production as well as the consumption side, on all levels, and need to cover not only technical aspects, but even more service solutions. While many of these solutions still need to be developed, some are already invented but only exist in limited market segments. Opening closed urban planning processes and using open innovation tools can foster bottom-up urban energy system transformation by addressing the interactive ways of decision-making integrating company representatives and citizens. While open innovation tools like (open) innovation workshops or ideas competitions are already used by several companies to find and develop new designs and products, there is yet little experience with energy efficiency ideas and bottom-up changes. Therefore, we analyse energy-efficient ideas generated in three different ideas competitions. We discuss the findings for theory and research on open innovation approaches and bottom-up urban changes. Our results show that there are a vast number of ideas available in the public. Open innovation tools offer advanced possibilities to generate energy-efficient solutions.

  20. Self-Organization Activities of College Students: Challenges and Opportunities

    Science.gov (United States)

    Shmurygina, Natalia; Bazhenova, Natalia; Bazhenov, Ruslan; Nikolaeva, Natalia; Tcytcarev, Andrey

    2016-01-01

    The article provides the analysis of self-organization activities of college students related to their participation in youth associations activities. The purpose of research is to disclose a degree of students' activities demonstration based on self-organization processes, assessment of existing self-organization practices of the youth,…

  1. Self organization of wireless sensor networks using ultra-wideband radios

    Science.gov (United States)

    Dowla, Farid U [Castro Valley, CA; Nekoogar, Franak [San Ramon, CA; Spiridon, Alex [Palo Alto, CA

    2009-06-16

    A novel UWB communications method and system that provides self-organization for wireless sensor networks is introduced. The self-organization is in terms of scalability, power conservation, channel estimation, and node synchronization in wireless sensor networks. The UWB receiver in the present invention adds two new tasks to conventional TR receivers. The two additional units are SNR enhancing unit and timing acquisition and tracking unit.

  2. Leader Election and Shape Formation with Self-Organizing Programmable Matter

    OpenAIRE

    Daymude, Joshua J.; Derakhshandeh, Zahra; Gmyr, Robert; Strothmann, Thim; Bazzi, Rida; Richa, Andréa W.; Scheideler, Christian

    2015-01-01

    We consider programmable matter consisting of simple computational elements, called particles, that can establish and release bonds and can actively move in a self-organized way, and we investigate the feasibility of solving fundamental problems relevant for programmable matter. As a suitable model for such self-organizing particle systems, we will use a generalization of the geometric amoebot model first proposed in SPAA 2014. Based on the geometric model, we present efficient local-control ...

  3. Do earthquakes exhibit self-organized criticality?

    International Nuclear Information System (INIS)

    Yang Xiaosong; Ma Jin; Du Shuming

    2004-01-01

    If earthquakes are phenomena of self-organized criticality (SOC), statistical characteristics of the earthquake time series should be invariant after the sequence of events in an earthquake catalog are randomly rearranged. In this Letter we argue that earthquakes are unlikely phenomena of SOC because our analysis of the Southern California Earthquake Catalog shows that the first-return-time probability P M (T) is apparently changed after the time series is rearranged. This suggests that the SOC theory should not be used to oppose the efforts of earthquake prediction

  4. Visions of sustainable urban energy systems. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Pietzsch, Ursula [HFT Stuttgart (Germany). zafh.net - Centre of Applied Research - Sustainable Energy Technology; Mikosch, Milena [Steinbeis-Zentrum, Stuttgart (Germany). Europaeischer Technologietransfer; Liesner, Lisa (eds.)

    2010-09-15

    Within the polycity final conference from 15th to 17th September, 2010, in Stuttgart (Federal Republic of Germany) the following lectures were held: (1) Visions of sustainable urban energy system (Ursula Eicker); (2) Words of welcome (Tanja Goenner); (3) Zero-energy Europe - We are on our way (Jean-Marie Bemtgen); (4) Polycity - Energy networks in sustainable cities An introduction (Ursula Pietzsch); (5) Energy efficient city - Successful examples in the European concerto initiative (Brigitte Bach); (6) Sustainable building and urban concepts in the Catalonian polycity project contributions to the polycity final conference 2010 (Nuria Pedrals); (7) Energy efficient buildings and renewable supply within the German polycity project (Ursula Eicker); (8) Energy efficient buildings and cities in the US (Thomas Spiegehalter); (9) Energy efficient communities - First results from an IEA collaboration project (Reinhard Jank); (10) The European energy performance of buildings directive (EPBD) - Lessons learned (Eduardo Maldonado); (11) Passive house standard in Europe - State-of-the-art and challenges (Wolfgang Feist); (12) High efficiency non-residential buildings: Concepts, implementations and experiences from the UK (Levin Lomas); (13) This is how we can save our world (Franz Alt); (14) Green buildings and renewable heating and cooling concepts in China (Yanjun Dai); (15) Sustainable urban energy solutions for Asia (Brahmanand Mohanty); (16) Description of ''Parc de l'Alba'' polygeneration system: A large-scale trigeneration system with district heating within the Spanish polycity project (Francesc Figueras Bellot); (17) Improved building automation and control systems with hardware-in-the loop solutions (Martin Becker); (18) The Italian polycity project area: Arquata (Luigi Fazari); (19) Photovoltaic system integration: In rehabilitated urban structures: Experiences and performance results from the Italian polycity project in Turin (Franco

  5. Urban stormwater - greywater management system for sustainable urban water management at sub-watershed level

    Science.gov (United States)

    Singh Arora, Amarpreet

    2017-11-01

    Urban water management involves urban water supply (import, treatment and distribution of water), urban wastewater management (collection, treatment and disposal of urban sewage) and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water), and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment) both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

  6. Self-organization process of a magnetohydrodynamic plasma in the presence of thermal conduction

    International Nuclear Information System (INIS)

    Zhu, Shao-ping; Horiuchi, Ritoku; Sato, Tetsuya; Watanabe, K.; Hayashi, T.; Todo, Y.; Watanabe, T.H.; Kageyama, A.; Takamaru, H.

    1995-12-01

    A self-organization process of a magnetohydrodynamic(MHD) plasma with a finite thermal conductivity is investigated by means of a three-dimensional MHD simulation. With no thermal conduction an MHD system self-organizes to a non-Taylor's state in which the electric current perpendicular to the magnetic field remains comparable to the parallel electric current. In the presence of thermal conductivity the perpendicular component of electric current and the nonuniformity of thermal pressure generated by driven reconnection tend to be smoothened. Thus, the self-organized state approaches to a force-free minimum energy state under the influence of thermal conduction. Detailed energy conversion processes are also studied to find that the rapid decay of magnetic energy during the self-organization process is caused not only through the ohmic heating, but also through the work done by the j x B force. (author)

  7. Revisit to self-organization of solitons for dissipative Korteweg-de Vries equation

    International Nuclear Information System (INIS)

    Kondoh, Y.; Van Dam, J.W.

    1995-03-01

    The process by which self-organization occurs for solitons described by the Korteweg-de Vries (KdV) equation with a viscous dissipation term is reinvestigated theoretically, with the use of numerical simulations in a periodic system. It is shown that, during nonlinear interactions, two basic processes for the self-organization of solitons are energy transfer and selective dissipation among the eigenmodes of the dissipative operator. It is also clarified that an important process during nonlinear self-organization is an interchange between the dominant operators, which has hitherto been overlooked in conventional self-organization theories and which leads to a final self-similar coherent structure determined uniquely by the dissipative operator

  8. The Self-Organized Archive: SPASE, PDS and Archive Cooperatives

    Science.gov (United States)

    King, T. A.; Hughes, J. S.; Roberts, D. A.; Walker, R. J.; Joy, S. P.

    2005-05-01

    Information systems with high quality metadata enable uses and services which often go beyond the original purpose. There are two types of metadata: annotations which are items that comment on or describe the content of a resource and identification attributes which describe the external properties of the resource itself. For example, annotations may indicate which columns are present in a table of data, whereas an identification attribute would indicate source of the table, such as the observatory, instrument, organization, and data type. When the identification attributes are collected and used as the basis of a search engine, a user can constrain on an attribute, the archive can then self-organize around the constraint, presenting the user with a particular view of the archive. In an archive cooperative where each participating data system or archive may have its own metadata standards, providing a multi-system search engine requires that individual archive metadata be mapped to a broad based standard. To explore how cooperative archives can form a larger self-organized archive we will show how the Space Physics Archive Search and Extract (SPASE) data model will allow different systems to create a cooperative and will use Planetary Data System (PDS) plus existing space physics activities as a demonstration.

  9. Self-organized critical behavior in pinned flux lattices

    International Nuclear Information System (INIS)

    Pla, O.; Nori, F.

    1991-01-01

    We study the response of pinned fluxed lattices, under small perturbations in the driving force, below and close to the pinning-depinning transition. For driving Lorentz forces below F c (the depinning force at which the whole flux lattice slides), the system has instabilities against small force increases, with a power-law distribution characteristic of self-organized criticality. Specifically, D(d)∼d -1,3 , where d is the displacement of a flux line after a very small force increase. We also study the initial stages of the motion of the lattice once the driving force overcomes the pinning forces

  10. Turbulence and Self-Organization Modeling Astrophysical Objects

    CERN Document Server

    Marov, Mikhail Ya

    2013-01-01

    This book focuses on the development of continuum models of natural turbulent media. It provides a theoretical approach to the solutions of different problems related to the formation, structure and evolution of astrophysical and geophysical objects. A stochastic modeling approach is used in the mathematical treatment of these problems, which reflects self-organization processes in open dissipative systems. The authors also consider examples of ordering for various objects in space throughout their evolutionary processes. This volume is aimed at graduate students and researchers in the fields of mechanics, astrophysics, geophysics, planetary and space science.

  11. Park system concept for environmental sustainabilityin urban spatial development

    Science.gov (United States)

    Uniaty, Q.

    2018-01-01

    Urban Park System is an integrated concept between nature system and urban life. The problems caused by urban population activity resulted in the need to increase the balance between two systems. Establishment of urban park system is a response to the need for resilience of urban space structures. As an ideal requirement it needs to be built integration between the ecological, social, economic, aesthetic aspects of urban landscape architecture. The methodology was developed based on an approach to issues affecting the conditions due to urban issues and its relation to the development efforts of urban park system; Observation of Jakarta problem was obtained based on published studies and data, literature, characteristic and potential analyzes, local physical, from limited field observations. Both are simple methods aimed to describe the nature of a condition as well as form characteristics of problems in controlling the development of region, to examine the causes and symptoms. This method try to assess an object study compared between the conditions before and after. The benefits of urban park system development will not only improve the urban environment, but the value of urban pride, identity and control urban growth in line with efforts to improve the balance between conservation and development. Integrated urban park system will enhance the multifunctional role, connectivity, habitability, durability, identity and investment.

  12. Distributed intelligent urban environment monitoring system

    Science.gov (United States)

    Du, Jinsong; Wang, Wei; Gao, Jie; Cong, Rigang

    2018-02-01

    The current environmental pollution and destruction have developed into a world-wide major social problem that threatens human survival and development. Environmental monitoring is the prerequisite and basis of environmental governance, but overall, the current environmental monitoring system is facing a series of problems. Based on the electrochemical sensor, this paper designs a small, low-cost, easy to layout urban environmental quality monitoring terminal, and multi-terminal constitutes a distributed network. The system has been small-scale demonstration applications and has confirmed that the system is suitable for large-scale promotion

  13. Structures in plasmas and their self-organizations

    International Nuclear Information System (INIS)

    Yoshida, Zensho

    1989-01-01

    This paper is a concise review of the physics of structures. The progress of the structure theory was motivated by the appearances of many different ordered structures that are self-organized through spontaneous dynamics. For typical examples in plasma physics, cited are the MHD equilibria (Taylor relaxed state), the ion acoustic solitons, and the van Kampen modes of continuous-spectrum Langmuir waves. A static theory for the intrinsic structures is developed to clarify the basic difference between the classical orders and the self-organized structures. In linear models, an intrinsic structure is characterized by a singular spectrum of a certain eigenvalue problem. The Taylor relaxed state is characterized by the continuum of the point spectra of the rotational operator. The general MHD equilibrium is related to a nonlinear eigenvalue problem. The soliton is a nonlinear eigenfunction of the Helmholtz-type Bohm equation. The variational expression of an intrinsic structure is characterized by restrictive functionals, which in a dynamical theory, is related to selective conservations. The Taylor relaxed state is obtained by minimizing the magnetic-field energy with conserving the magnetic helicity. This selective dissipation occurs in the fluctuations of kink modes. The soliton is self-organized by the dissipation of the Hamiltonian with keeping the energy approximately constant. The principle of the selective dissipation is logically a generalization of the ergodic hypothesis for the classical order and could be proved in a rigorous way by analyzing the attractor of the dynamical systems, just as the proof the ergodic theorem is obtained by the time-asymptotic analysis of a class of semigroups. (J.P.N.) 85 refs

  14. ICT INEQUALITIES IN THE SPANISH URBAN SYSTEM

    Directory of Open Access Journals (Sweden)

    Francisco Jose Armas QUINTA

    2010-12-01

    Full Text Available In the current Information Society cities enjoy a privileged position when it comes to transport and communication infrastructures. The post-industrial society has brought with it a notable change, changing from an economy based on the production of merchandise to another based on the production of services. The metropolitan areas act as key areas and markets for predominant sectors, such as finance and specialised services for business. In another way, big cities fulfil new roles in the global economy of the Information society, operating as command points in the world economy. They bring equipment together highly-qualified workers, they are big information and knowledge consumers and have been able to reinvent themselves, changing from industrial to cultural cities. They are, as well, ideal areas for big telecommunication companies and they are, for this reason, those who most benefit from information and communication technology. An important social area difference has then been introduced, with respect to other urban areas of lesser importance, or rather, with respect to rural areas that stay on the margin of the new technology revolution. In this context, it is right to ask what is happening in Spain. Why are ICT inequalities happening in Spain? Are there urban system differences before the arrival of the Information Society? Can it be said that Spanish urban areas are consolidated in the Information Society? In this article we try to outline the reality of the immersion the Information Society in the Spanish urban system, and, in the same way, bring to light a new idea of „Digital Divide‟, amongst those sectors of the population that make the most of all or a great part of the potential new technology offers and those that limit themselves to using the most basic functions, such as looking up information and using communication.

  15. Feedback, Lineages and Self-Organizing Morphogenesis.

    Directory of Open Access Journals (Sweden)

    Sameeran Kunche

    2016-03-01

    Full Text Available Feedback regulation of cell lineage progression plays an important role in tissue size homeostasis, but whether such feedback also plays an important role in tissue morphogenesis has yet to be explored. Here we use mathematical modeling to show that a particular feedback architecture in which both positive and negative diffusible signals act on stem and/or progenitor cells leads to the appearance of bistable or bi-modal growth behaviors, ultrasensitivity to external growth cues, local growth-driven budding, self-sustaining elongation, and the triggering of self-organization in the form of lamellar fingers. Such behaviors arise not through regulation of cell cycle speeds, but through the control of stem or progenitor self-renewal. Even though the spatial patterns that arise in this setting are the result of interactions between diffusible factors with antagonistic effects, morphogenesis is not the consequence of Turing-type instabilities.

  16. Self-organizing physical fields and gravity

    International Nuclear Information System (INIS)

    Pestov, I.B.

    2009-01-01

    It is shown that the Theory of Self-Organizing Physical Fields provides the adequate and consistent consideration of the gravitational phenomena. The general conclusion lies in the fact that the essence of gravidynamics is the new field concept of time and the general covariant law of energy conservation which in particular means that dark energy is simply the energy of the gravitational field. From the natural geometrical laws of gravidynamics the dynamical equations of the gravitational field are derived. Two exact solutions of these equations are obtained. One of them represents a shock gravitational wave and the other represents the Universe filled up with the gravitational energy only. These solutions are compared with the Schwarzschild and Friedmann solutions in the Einstein general theory of relativity

  17. Feedback, Lineages and Self-Organizing Morphogenesis

    Science.gov (United States)

    Calof, Anne L.; Lowengrub, John S.; Lander, Arthur D.

    2016-01-01

    Feedback regulation of cell lineage progression plays an important role in tissue size homeostasis, but whether such feedback also plays an important role in tissue morphogenesis has yet to be explored. Here we use mathematical modeling to show that a particular feedback architecture in which both positive and negative diffusible signals act on stem and/or progenitor cells leads to the appearance of bistable or bi-modal growth behaviors, ultrasensitivity to external growth cues, local growth-driven budding, self-sustaining elongation, and the triggering of self-organization in the form of lamellar fingers. Such behaviors arise not through regulation of cell cycle speeds, but through the control of stem or progenitor self-renewal. Even though the spatial patterns that arise in this setting are the result of interactions between diffusible factors with antagonistic effects, morphogenesis is not the consequence of Turing-type instabilities. PMID:26989903

  18. Self-organized modularization in evolutionary algorithms.

    Science.gov (United States)

    Dauscher, Peter; Uthmann, Thomas

    2005-01-01

    The principle of modularization has proven to be extremely successful in the field of technical applications and particularly for Software Engineering purposes. The question to be answered within the present article is whether mechanisms can also be identified within the framework of Evolutionary Computation that cause a modularization of solutions. We will concentrate on processes, where modularization results only from the typical evolutionary operators, i.e. selection and variation by recombination and mutation (and not, e.g., from special modularization operators). This is what we call Self-Organized Modularization. Based on a combination of two formalizations by Radcliffe and Altenberg, some quantitative measures of modularity are introduced. Particularly, we distinguish Built-in Modularity as an inherent property of a genotype and Effective Modularity, which depends on the rest of the population. These measures can easily be applied to a wide range of present Evolutionary Computation models. It will be shown, both theoretically and by simulation, that under certain conditions, Effective Modularity (as defined within this paper) can be a selection factor. This causes Self-Organized Modularization to take place. The experimental observations emphasize the importance of Effective Modularity in comparison with Built-in Modularity. Although the experimental results have been obtained using a minimalist toy model, they can lead to a number of consequences for existing models as well as for future approaches. Furthermore, the results suggest a complex self-amplification of highly modular equivalence classes in the case of respected relations. Since the well-known Holland schemata are just the equivalence classes of respected relations in most Simple Genetic Algorithms, this observation emphasizes the role of schemata as Building Blocks (in comparison with arbitrary subsets of the search space).

  19. Optimality and self-organization in river deltas

    Science.gov (United States)

    Tejedor, A.; Longjas, A.; Edmonds, D. A.; Zaliapin, I. V.; Georgiou, T. T.; Rinaldo, A.; Foufoula-Georgiou, E.

    2017-12-01

    Deltas are nourished by channel networks, whose connectivity constrains, if not drives, the evolution, functionality and resilience of these systems. Understanding the coevolution of deltaic channels and their flux organization is crucial for guiding maintenance strategies of these highly stressed systems from a range of anthropogenic activities. However, in contrast to tributary channel networks, to date, no theory has been proposed to explain how deltas self-organize to distribute water and sediment to the delta top and the shoreline. Here, we hypothesize the existence of an optimality principle underlying the self-organized partition of fluxes in delta channel networks. Specifically, we hypothesize that deltas distribute water and sediment fluxes on a given delta topology such as to maximize the diversity of flux delivery to the shoreline. By introducing the concept of nonlocal Entropy Rate (nER) and analyzing ten field deltas in diverse environments, we present evidence that supports our hypothesis, suggesting that delta networks achieve dynamically accessible maxima of their nER. Furthermore, by analyzing six simulated deltas using the Delf3D model and following their topologic and flux re-organization before and after major avulsions, we further study the evolution of nER and confirm our hypothesis. We discuss how optimal flux distributions in terms of nER, when interpreted in terms of resilience, are configurations that reflect an increased ability to withstand perturbations.

  20. Self-organizing map classifier for stressed speech recognition

    Science.gov (United States)

    Partila, Pavol; Tovarek, Jaromir; Voznak, Miroslav

    2016-05-01

    This paper presents a method for detecting speech under stress using Self-Organizing Maps. Most people who are exposed to stressful situations can not adequately respond to stimuli. Army, police, and fire department occupy the largest part of the environment that are typical of an increased number of stressful situations. The role of men in action is controlled by the control center. Control commands should be adapted to the psychological state of a man in action. It is known that the psychological changes of the human body are also reflected physiologically, which consequently means the stress effected speech. Therefore, it is clear that the speech stress recognizing system is required in the security forces. One of the possible classifiers, which are popular for its flexibility, is a self-organizing map. It is one type of the artificial neural networks. Flexibility means independence classifier on the character of the input data. This feature is suitable for speech processing. Human Stress can be seen as a kind of emotional state. Mel-frequency cepstral coefficients, LPC coefficients, and prosody features were selected for input data. These coefficients were selected for their sensitivity to emotional changes. The calculation of the parameters was performed on speech recordings, which can be divided into two classes, namely the stress state recordings and normal state recordings. The benefit of the experiment is a method using SOM classifier for stress speech detection. Results showed the advantage of this method, which is input data flexibility.

  1. Total Water Management, the New Paradigm for Urban Water Systems

    Science.gov (United States)

    There is a growing need for urban water managers to take a more holistic view of their water resource systems as population growth, urbanization, and current resource management practices put different stresses on local water resources and urban infrastructure. Total Water Manag...

  2. Self-Organization during Friction of Slide Bearing Antifriction Materials

    Directory of Open Access Journals (Sweden)

    Iosif S. Gershman

    2015-12-01

    Full Text Available This article discusses the peculiarities of self-organization behavior and formation of dissipative structures during friction of antifriction alloys for slide bearings against a steel counterbody. It shows that during self-organization, the moment of friction in a tribosystem may be decreasing with the load growth and in the bifurcations of the coefficient of friction with respect to load. Self-organization and the formation of dissipative structures lead to an increase in the seizure load.

  3. Analysis of mass incident diffusion in Weibo based on self-organization theory

    Science.gov (United States)

    Pan, Jun; Shen, Huizhang

    2018-02-01

    This study introduces some theories and methods of self-organization system to the research of the diffusion mechanism of mass incidents in Weibo (Chinese Twitter). Based on the analysis on massive Weibo data from Songjiang battery factory incident happened in 2013 and Jiiangsu Qidong OJI PAPER incident happened in 2012, we find out that diffusion system of mass incident in Weibo satisfies Power Law, Zipf's Law, 1/f noise and Self-similarity. It means this system is the self-organization criticality system and dissemination bursts can be understood as one kind of Self-organization behavior. As the consequence, self-organized criticality (SOC) theory can be used to explain the evolution of mass incident diffusion and people may come up with the right strategy to control such kind of diffusion if they can handle the key ingredients of Self-organization well. Such a study is of practical importance which can offer opportunities for policy makers to have good management on these events.

  4. Filamentary structures that self-organize due to adhesion

    Science.gov (United States)

    Sengab, A.; Picu, R. C.

    2018-03-01

    We study the self-organization of random collections of elastic filaments that interact adhesively. The evolution from an initial fully random quasi-two-dimensional state is controlled by filament elasticity, adhesion and interfilament friction, and excluded volume. Three outcomes are possible: the system may remain locked in the initial state, may organize into isolated fiber bundles, or may form a stable, connected network of bundles. The range of system parameters leading to each of these states is identified. The network of bundles is subisostatic and is stabilized by prestressed triangular features forming at bundle-to-bundle nodes, similar to the situation in foams. Interfiber friction promotes locking and expands the parametric range of nonevolving systems.

  5. Comprehensive evaluation system of intelligent urban growth

    Science.gov (United States)

    Li, Lian-Yan; Ren, Xiao-Bin

    2017-06-01

    With the rapid urbanization of the world, urban planning has become increasingly important and necessary to ensure people have access to equitable and sustainable homes, resources and jobs.This article is to talk about building an intelligent city evaluation system.First,using System Analysis Model(SAM) which concludes literature data analysis and stepwise regression analysis to describe intelligent growth scientifically and obtain the evaluation index. Then,using the improved entropy method to obtain the weight of the evaluation index.Afterwards, establishing a complete Smart Growth Comprehensive Evaluation Model(SGCEM).Finally,testing the correctness of the model.Choosing Otago(New Zealand )and Yumen(China) as research object by data mining and SGCEM model,then we get Yumen and Otago’s rational degree’s values are 0.3485 and 0.5376 respectively. It’s believed that the Otago’s smart level is higher,and it is found that the estimated value of rationality is consistent with the reality.

  6. Brain Basis of Self: Self-Organization and Lessons from Dreaming

    Directory of Open Access Journals (Sweden)

    David eKahn

    2013-07-01

    Full Text Available Through dreaming a different facet of the self is created as a result of a self-organizing process in the brain. Self-organization in biological systems often happens as an answer to an environmental change for which the existing system cannot cope; self-organization creates a system that can cope in the newly changed environment. In dreaming, self-organization serves the function of organizing disparate memories into a dream since the dreamer herself is not able to control how individual memories become weaved into a dream. The self-organized dream provides, thereby, a wide repertoire of experiences; this expanded repertoire of experience results in an expansion of the self beyond that obtainable when awake. Since expression of the self is associated with activity in specific areas of the brain, the article also discusses the brain basis of the self by reviewing studies of brain injured patients, discussing brain imaging studies in normal brain functioning when focused, when daydreaming and when asleep and dreaming.

  7. Self-organized critical model for protein folding

    Science.gov (United States)

    Moret, M. A.

    2011-09-01

    The major factor that drives a protein toward collapse and folding is the hydrophobic effect. At the folding process a hydrophobic core is shielded by the solvent-accessible surface area of the protein. We study the fractal behavior of 5526 protein structures present in the Brookhaven Protein Data Bank. Power laws of protein mass, volume and solvent-accessible surface area are measured independently. The present findings indicate that self-organized criticality is an alternative explanation for the protein folding. Also we note that the protein packing is an independent and constant value because the self-similar behavior of the volumes and protein masses have the same fractal dimension. This power law guarantees that a protein is a complex system. From the analyzed data, q-Gaussian distributions seem to fit well this class of systems.

  8. Experimental investigation of multiple self-organized structures in plasma

    International Nuclear Information System (INIS)

    Ivan, L. M.; Gaman, C.; Aflori, M.; Mihai-Plugaru, M.; Dimitriu, D.G.; Lozneanu, E.; Sanduloviciu, M.

    2005-01-01

    Complex space charge configuration emerges by self-organization in front of an electrode immersed in plasma when its potential is increased at a certain critical value. Consisting from a nucleus protected from the surrounding plasma by an electrical double layer, the complexity reveals an internal structure and behaviour which remind us primitive organisms. Thus the complexity is not static but stationary open system in which continuous decay is constantly compensated by substance and energy from the surrounding plasma. Endowed with a special kind of memory the complexity can work as an intelligent multifunctional system and consequently it is also able to perform innovations after selective interaction with an environment in evolution. Additionally, the complexity is able to replicate by division. (authors)

  9. Self-Organizing Maps for Fingerprint Image Quality Assessment

    DEFF Research Database (Denmark)

    Olsen, Martin Aastrup; Tabassi, Elham; Makarov, Anton

    2013-01-01

    Fingerprint quality assessment is a crucial task which needs to be conducted accurately in various phases in the biometric enrolment and recognition processes. Neglecting quality measurement will adversely impact accuracy and efficiency of biometric recognition systems (e.g. verification and iden......Fingerprint quality assessment is a crucial task which needs to be conducted accurately in various phases in the biometric enrolment and recognition processes. Neglecting quality measurement will adversely impact accuracy and efficiency of biometric recognition systems (e.g. verification...... machine learning techniques. We train a self-organizing map (SOM) to cluster blocks of fingerprint images based on their spatial information content. The output of the SOM is a high-level representation of the finger image, which forms the input to a Random Forest trained to learn the relationship between...

  10. Mechanisms of self-organization and finite size effects in a minimal agent based model

    International Nuclear Information System (INIS)

    Alfi, V; Cristelli, M; Pietronero, L; Zaccaria, A

    2009-01-01

    We present a detailed analysis of the self-organization phenomenon in which the stylized facts originate from finite size effects with respect to the number of agents considered and disappear in the limit of an infinite population. By introducing the possibility that agents can enter or leave the market depending on the behavior of the price, it is possible to show that the system self-organizes in a regime with a finite number of agents which corresponds to the stylized facts. The mechanism for entering or leaving the market is based on the idea that a too stable market is unappealing for traders, while the presence of price movements attracts agents to enter and speculate on the market. We show that this mechanism is also compatible with the idea that agents are scared by a noisy and risky market at shorter timescales. We also show that the mechanism for self-organization is robust with respect to variations of the exit/entry rules and that the attempt to trigger the system to self-organize in a region without stylized facts leads to an unrealistic dynamics. We study the self-organization in a specific agent based model but we believe that the basic ideas should be of general validity

  11. An urban energy performance evaluation system and its computer implementation.

    Science.gov (United States)

    Wang, Lei; Yuan, Guan; Long, Ruyin; Chen, Hong

    2017-12-15

    To improve the urban environment and effectively reflect and promote urban energy performance, an urban energy performance evaluation system was constructed, thereby strengthening urban environmental management capabilities. From the perspectives of internalization and externalization, a framework of evaluation indicators and key factors that determine urban energy performance and explore the reasons for differences in performance was proposed according to established theory and previous studies. Using the improved stochastic frontier analysis method, an urban energy performance evaluation and factor analysis model was built that brings performance evaluation and factor analysis into the same stage for study. According to data obtained for the Chinese provincial capitals from 2004 to 2013, the coefficients of the evaluation indicators and key factors were calculated by the urban energy performance evaluation and factor analysis model. These coefficients were then used to compile the program file. The urban energy performance evaluation system developed in this study was designed in three parts: a database, a distributed component server, and a human-machine interface. Its functions were designed as login, addition, edit, input, calculation, analysis, comparison, inquiry, and export. On the basis of these contents, an urban energy performance evaluation system was developed using Microsoft Visual Studio .NET 2015. The system can effectively reflect the status of and any changes in urban energy performance. Beijing was considered as an example to conduct an empirical study, which further verified the applicability and convenience of this evaluation system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Self-organization in a diversity induced thermodynamics.

    Science.gov (United States)

    Scirè, Alessandro; Annovazzi-Lodi, Valerio

    2017-01-01

    In this work we show how global self-organized patterns can come out of a disordered ensemble of point oscillators, as a result of a deterministic, and not of a random, cooperative process. The resulting system dynamics has many characteristics of classical thermodynamics. To this end, a modified Kuramoto model is introduced, by including Euclidean degrees of freedom and particle polarity. The standard deviation of the frequency distribution is the disorder parameter, diversity, acting as temperature, which is both a source of motion and of disorder. For zero and low diversity, robust static phase-synchronized patterns (crystals) appear, and the problem reverts to a generic dissipative many-body problem. From small to moderate diversity crystals display vibrations followed by structure disintegration in a competition of smaller dynamic patterns, internally synchronized, each of which is capable to manage its internal diversity. In this process a huge variety of self-organized dynamic shapes is formed. Such patterns can be seen again as (more complex) oscillators, where the same description can be applied in turn, renormalizing the problem to a bigger scale, opening the possibility of pattern evolution. The interaction functions are kept local because our idea is to build a system able to produce global patterns when its constituents only interact at the bond scale. By further increasing the oscillator diversity, the dynamics becomes erratic, dynamic patterns show short lifetime, and finally disappear for high diversity. Results are neither qualitatively dependent on the specific choice of the interaction functions nor on the shape of the probability function assumed for the frequencies. The system shows a phase transition and a critical behaviour for a specific value of diversity.

  13. Self-organized quantum rings : Physical characterization and theoretical modeling

    NARCIS (Netherlands)

    Fomin, V.M.; Gladilin, V.N.; Devreese, J.T.; Koenraad, P.M.; Fomin, V.M.

    2014-01-01

    An adequate modeling of the self-organized quantum rings is possible only on the basis of the modern characterization of those nanostructures.We discuss an atomic-scale analysis of the indium distribution of self-organized InGaAs quantum rings (QRs). The analysis of the shape, size and composition

  14. Self-organizing networks for extracting jet features

    International Nuclear Information System (INIS)

    Loennblad, L.; Peterson, C.; Pi, H.; Roegnvaldsson, T.

    1991-01-01

    Self-organizing neural networks are briefly reviewed and compared with supervised learning algorithms like back-propagation. The power of self-organization networks is in their capability of displaying typical features in a transparent manner. This is successfully demonstrated with two applications from hadronic jet physics; hadronization model discrimination and separation of b.c. and light quarks. (orig.)

  15. Self-organized complex space charge configurations at the origin of flicker noise

    International Nuclear Information System (INIS)

    Popescu, S.; Lozneanu, E.; Sanduloviciu, M.

    2003-01-01

    Based on experimental results obtained from a plasma diode we explain the fluctuations of the voltage supported by a non-linear gaseous conductor by the dynamical behavior of spatiotemporal patterns, in the form of moving double layers, formed after self-organization. Such phenomena appear when the system is subjected to an external constraint that creates and maintains a local gradient of electron kinetic energy. The described phenomenology suggests a plausible explanation for the appearance of flicker noise also in other physical systems, as for example semiconductors and, implicitly, offers a new model for the so-called self-organized criticality concept

  16. Optimizing cooling systems in Egyptian arid urbans

    International Nuclear Information System (INIS)

    Medhat, Ahmed A.; Khalil, Essam E.

    2006-01-01

    Present study is devoted to climatic and site oriented investigations that were carried out in a new rural development in the Upper-Egypt. Bioclimatic classifications considered Upper Egypt region, near Sudan border, as a Hot and Dry climatic region. [1]. that is affected by solar heat intensities that can reach 900 W/m2 for a period ranged from 5-to-7 hours per day with the presence of study storms. Cooling season extends up to eight months per year having Upper-day-bulb temperature ranged from 400 degree centigrade - to - 470 degree centigrade while Lower-dry-bulb-temperature ranged from 280 degree centigrade - to - 320 degree centigrade with the relative humidity ranged from 10%-to-37% RH. [2]. Site surveys and field experimental and analyses of the commonly used cooling systems were investigated, evaluated and optimized for optimum indoor comfort conditions at efficient energy efficiency. [3]. Extensive analyses were performed based on Psychrometric formulae to evaluate the impact of energy consumptions related to different cooling systems such as direct expansion, chilled water, and evaporative systems. the present study enables the critical investigations of the influence of arid outdoor conditions and the required indoor thermal parameters on the energy efficiencies of HVAC-system. This work; focuses on the suggestion of suitable system that should be implemented by local energy codes in these arid urban.(Author)

  17. Self-organization of mesoscopic silver wires by electrochemical deposition

    Directory of Open Access Journals (Sweden)

    Sheng Zhong

    2014-08-01

    Full Text Available Long, straight mesoscale silver wires have been fabricated from AgNO3 electrolyte via electrodeposition without the help of templates, additives, and surfactants. Although the wire growth speed is very fast due to growth under non-equilibrium conditions, the wire morphology is regular and uniform in diameter. Structural studies reveal that the wires are single-crystalline, with the [112] direction as the growth direction. A possible growth mechanism is suggested. Auger depth profile measurements show that the wires are stable against oxidation under ambient conditions. This unique system provides a convenient way for the study of self-organization in electrochemical environments as well as for the fabrication of highly-ordered, single-crystalline metal nanowires.

  18. Self-organized internal architectures of chiral micro-particles

    International Nuclear Information System (INIS)

    Provenzano, Clementina; Mazzulla, Alfredo; Desiderio, Giovanni; Pagliusi, Pasquale; De Santo, Maria P.; Cipparrone, Gabriella; Perrotta, Ida

    2014-01-01

    The internal architecture of polymeric self-assembled chiral micro-particles is studied by exploring the effect of the chirality, of the particle sizes, and of the interface/surface properties in the ordering of the helicoidal planes. The experimental investigations, performed by means of different microscopy techniques, show that the polymeric beads, resulting from light induced polymerization of cholesteric liquid crystal droplets, preserve both the spherical shape and the internal self-organized structures. The method used to create the micro-particles with controlled internal chiral architectures presents great flexibility providing several advantages connected to the acquired optical and photonics capabilities and allowing to envisage novel strategies for the development of chiral colloidal systems and materials

  19. Modeling self-organization of novel organic materials

    Science.gov (United States)

    Sayar, Mehmet

    In this thesis, the structural organization of oligomeric multi-block molecules is analyzed by computational analysis of coarse-grained models. These molecules form nanostructures with different dimensionalities, and the nanostructured nature of these materials leads to novel structural properties at different length scales. Previously, a number of oligomeric triblock rodcoil molecules have been shown to self-organize into mushroom shaped noncentrosymmetric nanostructures. Interestingly, thin films of these molecules contain polar domains and a finite macroscopic polarization. However, the fully polarized state is not the equilibrium state. In the first chapter, by solving a model with dipolar and Ising-like short range interactions, we show that polar domains are stable in films composed of aggregates as opposed to isolated molecules. Unlike classical molecular systems, these nanoaggregates have large intralayer spacings (a ≈ 6 nm), leading to a reduction in the repulsive dipolar interactions that oppose polar order within layers. This enables the formation of a striped pattern with polar domains of alternating directions. The energies of the possible structures at zero temperature are computed exactly and results of Monte Carlo simulations are provided at non-zero temperatures. In the second chapter, the macroscopic polarization of such nanostructured films is analyzed in the presence of a short range surface interaction. The surface interaction leads to a periodic domain structure where the balance between the up and down domains is broken, and therefore films of finite thickness have a net macroscopic polarization. The polarization per unit volume is a function of film thickness and strength of the surface interaction. Finally, in chapter three, self-organization of organic molecules into a network of one dimensional objects is analyzed. Multi-block organic dendron rodcoil molecules were found to self-organize into supramolecular nanoribbons (threads) and

  20. The sensitivity of Turing self-organization to biological feedback delays: 2D models of fish pigmentation

    KAUST Repository

    Gaffney, E. A.; Lee, S. S.

    2013-01-01

    © The authors 2013. Turing morphogen models have been extensively explored in the context of large-scale self-organization in multicellular biological systems. However, reconciling the detailed biology of morphogen dynamics, while accounting

  1. Urban Transportation Systems in Bogotá and Copenhagen

    DEFF Research Database (Denmark)

    Pineda, Andres Felipe Valderrama; Jørgensen, Ulrik

    2008-01-01

    In this paper we explore the socio-technical dynamics of developing new urban transport systems. Based on the analysis of empirical material from the study of the Transmilenio in Bogotá and the Metro in Copenhagen, we propose that the design, construction and operation of urban transport systems...

  2. Origin and evolution of the self-organizing cytoskeleton in the network of eukaryotic organelles.

    Science.gov (United States)

    Jékely, Gáspár

    2014-09-02

    The eukaryotic cytoskeleton evolved from prokaryotic cytomotive filaments. Prokaryotic filament systems show bewildering structural and dynamic complexity and, in many aspects, prefigure the self-organizing properties of the eukaryotic cytoskeleton. Here, the dynamic properties of the prokaryotic and eukaryotic cytoskeleton are compared, and how these relate to function and evolution of organellar networks is discussed. The evolution of new aspects of filament dynamics in eukaryotes, including severing and branching, and the advent of molecular motors converted the eukaryotic cytoskeleton into a self-organizing "active gel," the dynamics of which can only be described with computational models. Advances in modeling and comparative genomics hold promise of a better understanding of the evolution of the self-organizing cytoskeleton in early eukaryotes, and its role in the evolution of novel eukaryotic functions, such as amoeboid motility, mitosis, and ciliary swimming. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

  3. Operationalizing sustainability in urban coastal systems: a system dynamics analysis.

    Science.gov (United States)

    Mavrommati, Georgia; Bithas, Kostas; Panayiotidis, Panayiotis

    2013-12-15

    We propose a system dynamics approach for Ecologically Sustainable Development (ESD) in urban coastal systems. A systematic analysis based on theoretical considerations, policy analysis and experts' knowledge is followed in order to define the concept of ESD. The principles underlying ESD feed the development of a System Dynamics Model (SDM) that connects the pollutant loads produced by urban systems' socioeconomic activities with the ecological condition of the coastal ecosystem that it is delineated in operational terms through key biological elements defined by the EU Water Framework Directive. The receiving waters of the Athens Metropolitan area, which bears the elements of typical high population density Mediterranean coastal city but which currently has also new dynamics induced by the ongoing financial crisis, are used as an experimental system for testing a system dynamics approach to apply the concept of ESD. Systems' thinking is employed to represent the complex relationships among the components of the system. Interconnections and dependencies that determine the potentials for achieving ESD are revealed. The proposed system dynamics analysis can facilitate decision makers to define paths of development that comply with the principles of ESD. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Nanostructural self-organization and dynamic adaptation of metal-polymer tribosystems

    Science.gov (United States)

    Mashkov, Yu. K.

    2017-02-01

    The results of investigating the effect of nanosize modifiers of a polymer matrix on the nanostructural self-organization of polymer composites and dynamic adaptation of metal-polymer tribosystems, which considerably affect the wear resistance of polymer composite materials, have been analyzed. It has been shown that the physicochemical nanostructural self-organization processes are developed in metal-polymer tribosystems with the formation of thermotropic liquid-crystal structures of the polymer matrix, followed by the transition of the system to the stationary state with a negative feedback that ensures dynamic adaptation of the tribosystem to given operating conditions.

  5. Moving Towards a New Urban Systems Science

    Science.gov (United States)

    Peter M. Groffman; Mary L. Cadenasso; Jeannine Cavender-Bares; Daniel L. Childers; Nancy B. Grimm; Morgan Grove; Sarah E. Hobbie; Lucy R. Hutyra; G. Darrel Jenerette; Timon McPhearson; Diane E. Pataki; Steward T. A. Pickett; Richard V. Pouyat; Emma Rosi-Marshall; Benjamin L. Ruddell

    2016-01-01

    Research on urban ecosystems rapidly expanded in the 1990s and is now a central topic in ecosystem science. In this paper, we argue that there are two critical challenges for ecosystem science that are rooted in urban ecosystems: (1) predicting or explaining the assembly and function of novel communities and ecosystems under altered environmental conditions and (2)...

  6. Self-organization theories and environmental management: The case of South Moresby, Canada

    Science.gov (United States)

    Grzybowski, Alex G. S.; Slocombe, D. Scott

    1988-07-01

    This article presents a new approach to the analysis and management of large-scale societal problems with complex ecological, economic, and social dimensions. The approach is based on the theory of self-organizing systems—complex, open, far-from-equilibrium systems with nonlinear dynamics. A brief overview and comparison of different self-organization theories (synergetics, self-organization theory, hypercycles, and autopoiesis) is presented in order to isolate the key characteristics of such systems. The approach is used to develop an analysis of the landuse controversy in the South Moresby area of the Queen Charlotte Islands, British Columbia, Canada. Critical variables are identified for each subsystem and classified by spatial and temporal scale, and discussed in terms of information content and internal/external origin. Eradication of sea otters, introduction of black-tailed deer, impacts of large-scale clearcut logging, sustainability of the coastal forest industry, and changing relations between native peoples and governments are discussed in detail to illustrate the system dynamics of the South Moresby “sociobiophysical” system. Finally, implications of the self-organizing sociobiophysical system view for regional analysis and management are identified.

  7. Self-organization processes in field-invasion team sports : implications for leadership.

    Science.gov (United States)

    Passos, Pedro; Araújo, Duarte; Davids, Keith

    2013-01-01

    In nature, the interactions between agents in a complex system (fish schools; colonies of ants) are governed by information that is locally created. Each agent self-organizes (adjusts) its behaviour, not through a central command centre, but based on variables that emerge from the interactions with other system agents in the neighbourhood. Self-organization has been proposed as a mechanism to explain the tendencies for individual performers to interact with each other in field-invasion sports teams, displaying functional co-adaptive behaviours, without the need for central control. The relevance of self-organization as a mechanism that explains pattern-forming dynamics within attacker-defender interactions in field-invasion sports has been sustained in the literature. Nonetheless, other levels of interpersonal coordination, such as intra-team interactions, still raise important questions, particularly with reference to the role of leadership or match strategies that have been prescribed in advance by a coach. The existence of key properties of complex systems, such as system degeneracy, nonlinearity or contextual dependency, suggests that self-organization is a functional mechanism to explain the emergence of interpersonal coordination tendencies within intra-team interactions. In this opinion article we propose how leadership may act as a key constraint on the emergent, self-organizational tendencies of performers in field-invasion sports.

  8. Self-organized spectrum chunk selection algorithm for Local Area LTE-Advanced

    DEFF Research Database (Denmark)

    Kumar, Sanjay; Wang, Yuanye; Marchetti, Nicola

    2010-01-01

    This paper presents a self organized spectrum chunk selection algorithm in order to minimize the mutual intercell interference among Home Node Bs (HeNBs), aiming to improve the system throughput performance compared to the existing frequency reuse one scheme. The proposed algorithm is useful...

  9. Urban eco-efficiency and system dynamics modelling

    Energy Technology Data Exchange (ETDEWEB)

    Hradil, P., Email: petr.hradil@vtt.fi

    2012-06-15

    Assessment of urban development is generally based on static models of economic, social or environmental impacts. More advanced dynamic models have been used mostly for prediction of population and employment changes as well as for other macro-economic issues. This feasibility study was arranged to test the potential of system dynamic modelling in assessing eco-efficiency changes during urban development. (orig.)

  10. Features of monitoring system of physical state of urban bridges.

    Directory of Open Access Journals (Sweden)

    A.V. Bilchenko

    2011-12-01

    Full Text Available Abstract, the main features of urban bridge, structure are presented. The proposals concerning specialized management creation for exploitation, maintenance and reconstruction of bridges are developed. The essence of the new approach designed for the change of urban bridge structures physical state assessment system is stated.

  11. Assessment on Peri-Urban Dairy Production System and Evaluation ...

    African Journals Online (AJOL)

    Assessment on Peri-Urban Dairy Production System and Evaluation of Quality of Cows' Raw Milk: A Case of Shambu, Fincha and Kombolcha Towns of Horro Guduru Wollega Zone, Ethiopia. ... Science, Technology and Arts Research Journal ... Keywords: Bacterial load Ethiopia Horro Guduru Peri-Urban Dairying Raw milk ...

  12. Photoluminescence of self-organized perylene bisimide polymers

    NARCIS (Netherlands)

    Neuteboom, E.E.; Meskers, S.C.J.; Meijer, E.W.; Janssen, R.A.J.

    2004-01-01

    Three polymers consisting of alternating perylene bisimide chromophores and flexible polytetrahydrofuran segments of different length have been studied using absorption and (time-resolved) photoluminescence spectroscopy. In o-dichlorobenzene, the chromophores self organize to form H-like aggregates.

  13. Self-organizing maps: A tool to ascertain taxonomic relatedness ...

    Indian Academy of Sciences (India)

    MADHU

    what is known as numerical taxonomy (Garrity et al. 2001). ... Curvilinear component analysis; self-organizing maps; principal component analysis. Abbreviations used: ... This tool undergoes unsupervised learning and is particularly useful in ...

  14. Modelling the self-organization and collapse of complex networks

    Indian Academy of Sciences (India)

    Modelling the self-organization and collapse of complex networks. Sanjay Jain Department of Physics and Astrophysics, University of Delhi Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore Santa Fe Institute, Santa Fe, New Mexico.

  15. Symbiotic intelligence: Self-organizing knowledge on distributed networks, driven by human interaction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, N.; Joslyn, C.; Rocha, L.; Smith, S.; Kantor, M. [Los Alamos National Lab., NM (United States); Rasmussen, S. [Los Alamos National Lab., NM (United States)]|[Santa Fe Inst., NM (United States)

    1998-07-01

    This work addresses how human societies, and other diverse and distributed systems, solve collective challenges that are not approachable from the level of the individual, and how the Internet will change the way societies and organizations view problem solving. The authors apply the ideas developed in self-organizing systems to understand self-organization in informational systems. The simplest explanation as to why animals (for example, ants, wolves, and humans) are organized into societies is that these societies enhance the survival of the individuals which make up the populations. Individuals contribute to, as well as adapt to, these societies because they make life easier in one way or another, even though they may not always understand the process, either individually or collectively. Despite the lack of understanding of the how of the process, society during its existence as a species has changed significantly, from separate, small hunting tribes to a highly technological, globally integrated society. The authors combine this understanding of societal dynamics with self-organization on the Internet (the Net). The unique capability of the Net is that it combines, in a common medium, the entire human-technological system in both breadth and depth: breadth in the integration of heterogeneous systems of machines, information and people; and depth in the detailed capturing of the entire complexity of human use and creation of information. When the full diversity of societal dynamics is combined with the accuracy of communication on the Net, a phase transition is argued to occur in problem solving capability. Through conceptual examples, an experiment of collective decision making on the Net and a simulation showing the effect of noise and loss on collective decision making, the authors argue that the resulting symbiotic structure of humans and the Net will evolve as an alternative problem solving approach for groups, organizations and society. Self-organizing

  16. Innovative Mechanism of Rural Organization Based on Self-Organization

    OpenAIRE

    Wang, Xing jin; Gao, Bing

    2011-01-01

    The paper analyzes the basic situation for the formation of innovative rural organizations with the form of self-organization; revels the features of self-organization, including the four aspects of openness of rural organization, innovation of rural organization is far away from equilibrium, the non-linear response mechanism of rural organization innovation and the random rise and fall of rural organization innovation. The evolution mechanism of rural organization innovation is reveled accor...

  17. Extending Particle Swarm Optimisers with Self-Organized Criticality

    DEFF Research Database (Denmark)

    Løvbjerg, Morten; Krink, Thiemo

    2002-01-01

    Particle swarm optimisers (PSOs) show potential in function optimisation, but still have room for improvement. Self-organized criticality (SOC) can help control the PSO and add diversity. Extending the PSO with SOC seems promising reaching faster convergence and better solutions.......Particle swarm optimisers (PSOs) show potential in function optimisation, but still have room for improvement. Self-organized criticality (SOC) can help control the PSO and add diversity. Extending the PSO with SOC seems promising reaching faster convergence and better solutions....

  18. On micro-scale self-organization in a plasma

    International Nuclear Information System (INIS)

    Maluckov, A.; Jovanovic, M.S.; Skoric, M.M.; Sato, T.

    1998-01-01

    We concentrate on a nonlinear saturation of a stimulated Raman backscattering in an open convective weakly confined model in the context of micro-kinetic scale self-organization in plasmas. The results have led to an assertion that a long-time nonlinear saturation in an open SRBS model with phenomenological effects of anomalous dissipation, plasma heating and subsequent entropy expulsion, reveals a generic interrelation of self-organization at wave-fluid (macro) and particle-kinetic (micro) levels. (author)

  19. Linkages between the Urban Environment and Earth's Climate System

    Science.gov (United States)

    Shepherd, J. Marshall; Jin, Menglin

    2003-01-01

    Urbanization is one of the extreme cases of land use change. Although currently only 1.2% of the land is considered urban, the spatial coverage and density of cities are expected to rapidly increase in the near future. It is estimated that by the year 2025 60% of the world s population will live in cities (UNFP, 1999). Though urban areas are local in scale, human activity in urban environments has impacts at local, to global scale by changing atmospheric composition; impacting components of the water cycle; and modifying the carbon cycle 2nd ecosystems. For example, urban dwellers are undoubtedly familiar with "high" ozone pollution days, flash flooding in city streets, or heat stress on summer days. However, our understanding of urbanization on the total Earth-climate system is incomplete. Better understanding of how the Earth s weather, oceans, and land work together and the influence of the urban environment on this climate system is critical. This paper highlights some of the major and current issues involving interactions between urban environments and the Earth's climate system. It also captures some of the most current thinking and findings of the authors and key experts in the field.

  20. Effect of prediction on the self-organization of pedestrian counter flow

    International Nuclear Information System (INIS)

    Wang Ziyang; Zhao Hui; Ma Jian; Qin Yong; Jia Limin

    2012-01-01

    Pedestrians may predict the behavior of others and then adjust their movement accordingly to avoid potential conflicts in advance. Motivated by this fact, we propose a predictive control theory-based pedestrian counter flow model, which describes the predictive mechanism underlying pedestrian self-organization phenomena. In this model, a pedestrian will make in-advance-avoid behavior based on the estimation of future moving gain within a given predictive length to reduce potential conflicts. The future gain in the present model is affected by three factors, i.e. the predictive length, the smooth degree of entrance and the influential area of coming pedestrians. Simulation results of the model show that increasing predictive length has a remarkable effect on reducing conflicts, improving pedestrian velocity, smoothing pedestrian movement and stabilizing the self-organized lanes. When enlarging the influential area of coming pedestrians, pedestrians tend to aggregate to the formed self-organized lanes, which makes the lanes wider and the lane number reduced. Interestingly, moderate enlargement (of the influential area) will reduce conflicts significantly, while excessive enlargement will lead to an increase in conflicts. We also discuss the predictive effect toward the smooth degree of entrance. When there are some formed self-organized lanes in the system, the effect is significant, and it will make the lanes more regular and stable, while when the existing lanes are unstable, the effect has little impact on the system. (paper)

  1. Urban traffic simulated from the dual representation: Flow, crisis and congestion

    International Nuclear Information System (INIS)

    Hu Maobin; Jiang Rui; Wang Ruili; Wu Qingsong

    2009-01-01

    We propose a traffic simulation model for urban system based on the dual graph representation of a urban road network and with a random entering vehicle rate. To avoid the shortcoming of 'Space Syntax' of ignoring the road's metric distance, we consider both the motion of the vehicles along roads and the navigation of the vehicles in the network. Simulations have shown some basic properties of urban traffic system, such as flux fluctuation, crisis and dissipation, phase transition from a free flow to jams, overall capacity, the distribution of traveling time, and the fundamental diagram. The system's behavior greatly depends on the topology of the transportation network. A well-planned lattice grid can keep more vehicles travelling. The critical entering vehicle rate is much greater in lattice grid than in a self-organized network. The vehicles have to travel longer time in a self-organized urban system due to the navigation cost.

  2. Integrated Urban Wastewater System Data Network - Data network system : Diagnostic Report Cali, Colombia

    NARCIS (Netherlands)

    Unesco-IHE

    2008-01-01

    The pressure on the Urban Wastewater Systems (UWwS) increases as urbanization continues relentlessly and climate change appears to lead to more extreme rainfall events. These pressures have a negative effect on the efficiency of UWwS to reduce the urban pollution reaching water-receiving systems.

  3. Sustained activity in hierarchical modular neural networks: self-organized criticality and oscillations

    Directory of Open Access Journals (Sweden)

    Sheng-Jun Wang

    2011-06-01

    Full Text Available Cerebral cortical brain networks possess a number of conspicuous features of structure and dynamics. First, these networks have an intricate, non-random organization. They are structured in a hierarchical modular fashion, from large-scale regions of the whole brain, via cortical areas and area subcompartments organized as structural and functional maps to cortical columns, and finally circuits made up of individual neurons. Second, the networks display self-organized sustained activity, which is persistent in the absence of external stimuli. At the systems level, such activity is characterized by complex rhythmical oscillations over a broadband background, while at the cellular level, neuronal discharges have been observed to display avalanches, indicating that cortical networks are at the state of self-organized criticality. We explored the relationship between hierarchical neural network organization and sustained dynamics using large-scale network modeling. It was shown that sparse random networks with balanced excitation and inhibition can sustain neural activity without external stimulation. We find that a hierarchical modular architecture can generate sustained activity better than random networks. Moreover, the system can simultaneously support rhythmical oscillations and self-organized criticality, which are not present in the respective random networks. The underlying mechanism is that each dense module cannot sustain activity on its own, but displays self-organized criticality in the presence of weak perturbations. The hierarchical modular networks provide the coupling among subsystems with self-organized criticality. These results imply that the hierarchical modular architecture of cortical networks plays an important role in shaping the ongoing spontaneous activity of the brain, potentially allowing the system to take advantage of both the sensitivityof critical state and predictability and timing of oscillations for efficient

  4. Sustainable Urban Agriculture in Ghana: What Governance System Works?

    Directory of Open Access Journals (Sweden)

    Eileen Bogweh Nchanji

    2017-11-01

    Full Text Available Urban farming takes advantage of its proximity to market, transport and other urban infrastructure to provide food for the city and sustain the livelihoods of urban and peri-urban dwellers. It is an agricultural activity which employs more than 50% of the local urban population with positive and negative impacts on local and national development. Urban agriculture is an informal activity not supported by law but in practice is regulated to a certain extent by state institutions, traditional rulers, farmers and national and international non-governmental organisations. Tamale’s rapid population growth, exacerbated by the unplanned development system and institutional conflicts, are factors contributing to the present bottlenecks in the urban agricultural system. In this paper, these bottlenecks are conceptualised as problems of governance. These issues will be illustrated using ethnographic data from land sales, crop-livestock competition, waste-water irrigation, and markets. I will explain how conflicts which arise from these different situations are resolved through the interactions of various governance systems. Informal governance arrangements are widespread, but neither they nor formal systems are always successful in resolving governance issues. A participatory governance does not seem possible due to actors’ divergent interests. A governance solution for this sector is not yet apparent, contributing to food and nutritional insecurity.

  5. REVIEW OF THE EUROPEAN SYSTEMS RESEARCH PROGRAMS OF URBAN TERRITORIES

    Directory of Open Access Journals (Sweden)

    L. N. Kovalskyi

    2017-01-01

    Full Text Available The model of sustainable development of the territory should be in a state of control and management. The system of urban monitoring of Ukraine does not fully provide information on the level of sustainable development of settlements and regions. Therefore, it is necessary to create systems for monitoring indicators of sustainable development of human settlements and regions. The objective of this study is to analyze the existing programs for stimulating sustainable development in European countries and to develop recommendations on the need to organize such systems in Ukraine and to improve the system of urban monitoring. The article describes such systems and programs: URBACT is a program for sharing best practices between cities by creating thematic networks. URBACT’s mission is to encourage cities to work together and develop integrated solutions to common urban problems, through networking, to learn from each other’s experiences and identify best practices in order to improve urban policies; URBAN AUDIT – a large set of statistical information. The main objective of the system is to provide objective and comparable statistical data on European cities; URBAN ATLAS – provides a pan-European comparison of urban land use data. The information is in the form of open geospatial data. The system is aimed at facilitating work on site planning and site accounting. It is necessary to adopt the best practices of implementing sustainable development technology and apply it in other countries that have chosen a model for their development – a model for sustainable development of the territory. The current system of town-planning monitoring in Ukraine needs to be improved and given a new task – to take into account indicators of sustainable development of the territories. This system is most suitable for this task, since urban monitoring already takes into account certain indicators in the form of spatial data.

  6. Self-organization of intracellular gradients during mitosis

    Directory of Open Access Journals (Sweden)

    Fuller Brian G

    2010-01-01

    Full Text Available Abstract Gradients are used in a number of biological systems to transmit spatial information over a range of distances. The best studied are morphogen gradients where information is transmitted over many cell lengths. Smaller mitotic gradients reflect the need to organize several distinct events along the length of the mitotic spindle. The intracellular gradients that characterize mitosis are emerging as important regulatory paradigms. Intracellular gradients utilize intrinsic auto-regulatory feedback loops and diffusion to establish stable regions of activity within the mitotic cytosol. We review three recently described intracellular mitotic gradients. The Ran GTP gradient with its elaborate cascade of nuclear transport receptors and cargoes is the best characterized, yet the dynamics underlying the robust gradient of Ran-GTP have received little attention. Gradients of phosphorylation have been observed on Aurora B kinase substrates both before and after anaphase onset. In both instances the phosphorylation gradient appears to result from a soluble gradient of Aurora B kinase activity. Regulatory properties that support gradient formation are highlighted. Intracellular activity gradients that regulate localized mitotic events bare several hallmarks of self-organizing biologic systems that designate spatial information during pattern formation. Intracellular pattern formation represents a new paradigm in mitotic regulation.

  7. Spontaneous neuronal activity as a self-organized critical phenomenon

    Science.gov (United States)

    de Arcangelis, L.; Herrmann, H. J.

    2013-01-01

    Neuronal avalanches are a novel mode of activity in neuronal networks, experimentally found in vitro and in vivo, and exhibit a robust critical behaviour. Avalanche activity can be modelled within the self-organized criticality framework, including threshold firing, refractory period and activity-dependent synaptic plasticity. The size and duration distributions confirm that the system acts in a critical state, whose scaling behaviour is very robust. Next, we discuss the temporal organization of neuronal avalanches. This is given by the alternation between states of high and low activity, named up and down states, leading to a balance between excitation and inhibition controlled by a single parameter. During these periods both the single neuron state and the network excitability level, keeping memory of past activity, are tuned by homeostatic mechanisms. Finally, we verify if a system with no characteristic response can ever learn in a controlled and reproducible way. Learning in the model occurs via plastic adaptation of synaptic strengths by a non-uniform negative feedback mechanism. Learning is a truly collective process and the learning dynamics exhibits universal features. Even complex rules can be learned provided that the plastic adaptation is sufficiently slow.

  8. Pressure-Point Strategy: Leverages for Urban Systemic Transformation

    Directory of Open Access Journals (Sweden)

    Katleen De Flander

    2017-01-01

    Full Text Available Sustainability can be understood as a specific kind of problem framing that emphasizes the interconnectedness of different problems and scales and calls for new forms of problem handling that are much more process-oriented, reflexive and iterative in nature. Closely related with the notion of reflexive governance, we propose such an alternative strategy for societal problem handling and change management in the urban context. The strategy starts from stress states in the urban system(s and uses their initial momentum to encourage systemic change through intraventions—rather than interventions—at selected pressure points. This paper highlights the potential to evolve what has often been an intuitive practice, led by community or elected leaders with unique wisdom about functions and pressure points in their urban system, into a more accessible strategy for shaping socio-ecological transformation in urban practice.

  9. Nonlinear dynamics analysis of a self-organizing recurrent neural network: chaos waning.

    Science.gov (United States)

    Eser, Jürgen; Zheng, Pengsheng; Triesch, Jochen

    2014-01-01

    Self-organization is thought to play an important role in structuring nervous systems. It frequently arises as a consequence of plasticity mechanisms in neural networks: connectivity determines network dynamics which in turn feed back on network structure through various forms of plasticity. Recently, self-organizing recurrent neural network models (SORNs) have been shown to learn non-trivial structure in their inputs and to reproduce the experimentally observed statistics and fluctuations of synaptic connection strengths in cortex and hippocampus. However, the dynamics in these networks and how they change with network evolution are still poorly understood. Here we investigate the degree of chaos in SORNs by studying how the networks' self-organization changes their response to small perturbations. We study the effect of perturbations to the excitatory-to-excitatory weight matrix on connection strengths and on unit activities. We find that the network dynamics, characterized by an estimate of the maximum Lyapunov exponent, becomes less chaotic during its self-organization, developing into a regime where only few perturbations become amplified. We also find that due to the mixing of discrete and (quasi-)continuous variables in SORNs, small perturbations to the synaptic weights may become amplified only after a substantial delay, a phenomenon we propose to call deferred chaos.

  10. Actomyosin-based Self-organization of cell internalization during C. elegans gastrulation

    Directory of Open Access Journals (Sweden)

    Pohl Christian

    2012-11-01

    Full Text Available Abstract Background Gastrulation is a key transition in embryogenesis; it requires self-organized cellular coordination, which has to be both robust to allow efficient development and plastic to provide adaptability. Despite the conservation of gastrulation as a key event in Metazoan embryogenesis, the morphogenetic mechanisms of self-organization (how global order or coordination can arise from local interactions are poorly understood. Results We report a modular structure of cell internalization in Caenorhabditis elegans gastrulation that reveals mechanisms of self-organization. Cells that internalize during gastrulation show apical contractile flows, which are correlated with centripetal extensions from surrounding cells. These extensions converge to seal over the internalizing cells in the form of rosettes. This process represents a distinct mode of monolayer remodeling, with gradual extrusion of the internalizing cells and simultaneous tissue closure without an actin purse-string. We further report that this self-organizing module can adapt to severe topological alterations, providing evidence of scalability and plasticity of actomyosin-based patterning. Finally, we show that globally, the surface cell layer undergoes coplanar division to thin out and spread over the internalizing mass, which resembles epiboly. Conclusions The combination of coplanar division-based spreading and recurrent local modules for piecemeal internalization constitutes a system-level solution of gradual volume rearrangement under spatial constraint. Our results suggest that the mode of C. elegans gastrulation can be unified with the general notions of monolayer remodeling and with distinct cellular mechanisms of actomyosin-based morphogenesis.

  11. Exponential Self-Organization and Moore’s Law: Measures and Mechanisms

    OpenAIRE

    Georgiev, Georgi Yordanov; Chatterjee, Atanu; Iannacchione, Germano

    2017-01-01

    The question of how complex systems become more organized and efficient with time is open. Examples are the formation of elementary particles from pure energy, the formation of atoms from particles, the formation of stars and galaxies, and the formation of molecules from atoms, of organisms, and of the society. In this sequence, order appears inside complex systems and randomness (entropy) is expelled to their surroundings. Key features of self-organizing systems are that they are open and th...

  12. Self-organization of the critical state in Josephson lattices and granulated superconductors

    International Nuclear Information System (INIS)

    Ginzburg, S.L.

    1994-01-01

    A number of models of a Josephson medium and granulated superconductors are studied. It is shown that an important parameter is the quantity V∼j c a 3 /Φ 0 , where j c is the Josephson-current density, a is the granule size, and Φ 0 is the quantum of flux. In the limit V>>1 the continuum approximation is inapplicable. In this case the Josephson medium is transformed into a system in which pinning is realized on elementary loops that incorporate Josephson junctions. Here, nonlinear properties of these junctions obtain. The equations obtained for the currents of the Josephson lattice are identical to the standard formulation in the problem of self-organized criticality, while in granulated superconductors a problem of self-organized criticality with a different symmetry arises-a problem not of sites, but of loop. From the point of view of the critical state in granulated superconductors the concept of self-organized criticality radically changes the entire customary picture. The usual equations of the critical state describe only the average values of the magnetic field in the hydrodynamic approximation. However, it follows from the concept of self-organized criticality that the critical state has an extremely complicated structure, much more complicated than that which follows from the equation of the critical state. In particular, the fluctuations of various quantities in the critical state are much stronger than the ordinary statistical fluctuations, since there are large-scale fluctuations of the currents and fields, with a power-law (scaling) behavior that extends up to scales of the order of the size of the system, as in a turbulent medium. On the other hand, the basic equations in it reflect all the features of pinning - hysteresis and threshold behavior. Therefore, the self-organization of the critical state of a superconductor is a natural realization of this extremely general problem. 15 refs., 4 figs

  13. A systems approach to reduce urban rail energy consumption

    International Nuclear Information System (INIS)

    González-Gil, A.; Palacin, R.; Batty, P.; Powell, J.P.

    2014-01-01

    Highlights: • An insightful overview of energy usage in urban rail systems is given. • The principal measures to reduce urban rail energy consumption are appraised. • A methodology is proposed to help implement energy saving schemes in urban rail. • Regenerative braking is shown to offer the greatest energy saving potential. - Abstract: There is increasing interest in the potential of urban rail to reduce the impact of metropolitan transportation due to its high capacity, reliability and absence of local emissions. However, in a context characterised by increasing capacity demands and rising energy costs, and where other transport modes are considerably improving their environmental performance, urban rail must minimise its energy use without affecting its service quality. Urban rail energy consumption is defined by a wide range of interdependent factors; therefore, a system wide perspective is required, rather than focusing on energy savings at subsystem level. This paper contributes to the current literature by proposing an holistic approach to reduce the overall energy consumption of urban rail. Firstly, a general description of this transport mode is given, which includes an assessment of its typical energy breakdown. Secondly, a comprehensive appraisal of the main practices, strategies and technologies currently available to minimise its energy use is provided. These comprise: regenerative braking, energy-efficient driving, traction losses reduction, comfort functions optimisation, energy metering, smart power management and renewable energy micro-generation. Finally, a clear, logical methodology is described to optimally define and implement energy saving schemes in urban rail systems. This includes general guidelines for a qualitative assessment and comparison of measures alongside a discussion on the principal interdependences between them. As a hypothetical example of application, the paper concludes that the energy consumption in existing urban

  14. Self-organization of spatio-temporal earthquake clusters

    Directory of Open Access Journals (Sweden)

    S. Hainzl

    2000-01-01

    Full Text Available Cellular automaton versions of the Burridge-Knopoff model have been shown to reproduce the power law distribution of event sizes; that is, the Gutenberg-Richter law. However, they have failed to reproduce the occurrence of foreshock and aftershock sequences correlated with large earthquakes. We show that in the case of partial stress recovery due to transient creep occurring subsequently to earthquakes in the crust, such spring-block systems self-organize into a statistically stationary state characterized by a power law distribution of fracture sizes as well as by foreshocks and aftershocks accompanying large events. In particular, the increase of foreshock and the decrease of aftershock activity can be described by, aside from a prefactor, the same Omori law. The exponent of the Omori law depends on the relaxation time and on the spatial scale of transient creep. Further investigations concerning the number of aftershocks, the temporal variation of aftershock magnitudes, and the waiting time distribution support the conclusion that this model, even "more realistic" physics in missed, captures in some ways the origin of the size distribution as well as spatio-temporal clustering of earthquakes.

  15. Impact of network topology on self-organized criticality

    Science.gov (United States)

    Hoffmann, Heiko

    2018-02-01

    The general mechanisms behind self-organized criticality (SOC) are still unknown. Several microscopic and mean-field theory approaches have been suggested, but they do not explain the dependence of the exponents on the underlying network topology of the SOC system. Here, we first report the phenomena that in the Bak-Tang-Wiesenfeld (BTW) model, sites inside an avalanche area largely return to their original state after the passing of an avalanche, forming, effectively, critically arranged clusters of sites. Then, we hypothesize that SOC relies on the formation process of these clusters, and present a model of such formation. For low-dimensional networks, we show theoretically and in simulation that the exponent of the cluster-size distribution is proportional to the ratio of the fractal dimension of the cluster boundary and the dimensionality of the network. For the BTW model, in our simulations, the exponent of the avalanche-area distribution matched approximately our prediction based on this ratio for two-dimensional networks, but deviated for higher dimensions. We hypothesize a transition from cluster formation to the mean-field theory process with increasing dimensionality. This work sheds light onto the mechanisms behind SOC, particularly, the impact of the network topology.

  16. Self-organized fluorescent nanosensors for ratiometric Pb2+ detection.

    Science.gov (United States)

    Arduini, Maria; Mancin, Fabrizio; Tecilla, Paolo; Tonellato, Umberto

    2007-07-31

    Silica nanoparticles (60 nm diameter) doped with fluorescent dyes and functionalized on the surface with thiol groups have been proved to be efficient fluorescent chemosensors for Pb2+ ions. The particles can detect a 1 microM metal ion concentration with a good selectivity, suffering only interference from Cu2+ ions. Analyte binding sites are provided by the simple grafting of the thiol groups on the nanoparticles. Once bound to the particles surface, the Pb2+ ions quench the emission of the reporting dyes embedded. Sensor performances can be improved by taking advantage of the ease of production of multishell silica particles. On one hand, signaling units can be concentrated in the external shells, allowing a closer interaction with the surface-bound analyte. On the other, a second dye can be buried in the particle core, far enough from the surface to be unaffected by the Pb2+ ions, thus producing a reference signal. In this way, a ratiometric system is easily prepared by simple self-organization of the particle components.

  17. Self-organized criticality in developing neuronal networks.

    Directory of Open Access Journals (Sweden)

    Christian Tetzlaff

    Full Text Available Recently evidence has accumulated that many neural networks exhibit self-organized criticality. In this state, activity is similar across temporal scales and this is beneficial with respect to information flow. If subcritical, activity can die out, if supercritical epileptiform patterns may occur. Little is known about how developing networks will reach and stabilize criticality. Here we monitor the development between 13 and 95 days in vitro (DIV of cortical cell cultures (n = 20 and find four different phases, related to their morphological maturation: An initial low-activity state (≈19 DIV is followed by a supercritical (≈20 DIV and then a subcritical one (≈36 DIV until the network finally reaches stable criticality (≈58 DIV. Using network modeling and mathematical analysis we describe the dynamics of the emergent connectivity in such developing systems. Based on physiological observations, the synaptic development in the model is determined by the drive of the neurons to adjust their connectivity for reaching on average firing rate homeostasis. We predict a specific time course for the maturation of inhibition, with strong onset and delayed pruning, and that total synaptic connectivity should be strongly linked to the relative levels of excitation and inhibition. These results demonstrate that the interplay between activity and connectivity guides developing networks into criticality suggesting that this may be a generic and stable state of many networks in vivo and in vitro.

  18. Self-organizing maps based on limit cycle attractors.

    Science.gov (United States)

    Huang, Di-Wei; Gentili, Rodolphe J; Reggia, James A

    2015-03-01

    Recent efforts to develop large-scale brain and neurocognitive architectures have paid relatively little attention to the use of self-organizing maps (SOMs). Part of the reason for this is that most conventional SOMs use a static encoding representation: each input pattern or sequence is effectively represented as a fixed point activation pattern in the map layer, something that is inconsistent with the rhythmic oscillatory activity observed in the brain. Here we develop and study an alternative encoding scheme that instead uses sparsely-coded limit cycles to represent external input patterns/sequences. We establish conditions under which learned limit cycle representations arise reliably and dominate the dynamics in a SOM. These limit cycles tend to be relatively unique for different inputs, robust to perturbations, and fairly insensitive to timing. In spite of the continually changing activity in the map layer when a limit cycle representation is used, map formation continues to occur reliably. In a two-SOM architecture where each SOM represents a different sensory modality, we also show that after learning, limit cycles in one SOM can correctly evoke corresponding limit cycles in the other, and thus there is the potential for multi-SOM systems using limit cycles to work effectively as hetero-associative memories. While the results presented here are only first steps, they establish the viability of SOM models based on limit cycle activity patterns, and suggest that such models merit further study. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Self-organization in three-dimensional compressible magnetohydrodynamic flow

    International Nuclear Information System (INIS)

    Horiuchi, Ritoku; Sato, Tetsuya.

    1987-07-01

    A three-dimensional self-organization process of a compressible dissipative plasma with a velocity-magnetic field correlation is investigated in detail by means of a variational method and a magnetohydrodynamic simulation. There are two types of relaxation, i.e., fast relaxation in which the cross helicity is not conserved, and slow relaxation in which the cross helicity is approximately conserved. In the slow relaxation case the cross helicity consists of two components with opposite sign which have almost the same amplitude in the large wavenumber region. In both cases the system approaches a high correlation state, dependent on the initial condition. These results are consistent with an observational data of the solar wind. Selective dissipation of magnetic energy, normal cascade of magnetic energy spectrum and inverse cascade of magnetic helicity spectrum are observed for the sub-Alfvenic flow case as was previously observed for the zero flow case. When the flow velocity is super-Alfvenic, the relaxation process is significantly altered from the zero flow case. (author)

  20. Deliberative Self-Organizing Traffic Lights with Elementary Cellular Automata

    Directory of Open Access Journals (Sweden)

    Jorge L. Zapotecatl

    2017-01-01

    Full Text Available Self-organizing traffic lights have shown considerable improvements compared to traditional methods in computer simulations. Self-organizing methods, however, use sophisticated sensors, increasing their cost and limiting their deployment. We propose a novel approach using simple sensors to achieve self-organizing traffic light coordination. The proposed approach involves placing a computer and a presence sensor at the beginning of each block; each such sensor detects a single vehicle. Each computer builds a virtual environment simulating vehicle movement to predict arrivals and departures at the downstream intersection. At each intersection, a computer receives information across a data network from the computers of the neighboring blocks and runs a self-organizing method to control traffic lights. Our simulations showed a superior performance for our approach compared with a traditional method (a green wave and a similar performance (close to optimal compared with a self-organizing method using sophisticated sensors but at a lower cost. Moreover, the developed sensing approach exhibited greater robustness against sensor failures.

  1. Current research trend on urban sewerage system in China

    Science.gov (United States)

    Ning, Yun-Fang; Dong, Wen-Yi; Lin, Lu-Sheng; Zhang, Qian

    2017-03-01

    The research emphasis has always been on sewerage treatment technology in China, though urban drainage system has gained little attention. In the context of urban drainage system and the problem associated with rain, the focus is still mainly toward the simple “emissions”. While the relationship between conservation and utilization of rainwater resources and urban ecology are popular, the relationship between rainwater discharge and non-point source pollution are often neglected. The reasonable choice of sewerage system is dependent on the collection and discharge of urban sewerage, the applicability and economic benefits, along with the ability to meet the water quality requirements and environmental protection. This paper analyzes and summarizes the development of urban drainage system in china, and introduces different drainage forms. The choice of drainage system should be based on the overall planning of the city, environmental protection requirements, the local natural conditions and water conditions, urban sewerage and water quality, the original drainage facilities, and local climatic conditions. It must be comprehensive to meet the environmental protection requirements, through technical and economic comparison.

  2. Self-Organization of Internet Paths

    NARCIS (Netherlands)

    Kleiberg, T.; Van Mieghem, P.

    2009-01-01

    The Internet consists of a constantly evolving complex hierarchical architecture where routers are grouped into autonomous systems (ASes) that interconnect to provide global connectivity. Routing is generally performed in a decentralized fashion, where each router determines the route to the

  3. Urban Water Innovation Network (UWIN): Transitioning Toward Sustainbale Urban Water Systems

    Science.gov (United States)

    Arabi, M.

    2015-12-01

    City water systems are at risk of disruption from global social and environmental hazards, which could have deleterious effects on human health, property, and loss of critical infrastructure. The Urban Water Innovation Network (UWIN), a consortium of 14 academic institutions and other key partners across the U.S., is working to address challenges that threaten urban water systems across the nation. UWIN's mission is to create technological, institutional and management solutions to help communities increase the resilience of their water systems and enhance their preparedness for responding to water crisis. The network seeks solutions that achieve widespread adoption consistent with inclusive, equitable and sustainable urban development. The integrative and adaptive analysis framework of UWIN is presented. The framework identifies a toolbox of sustainable solutions by simultaneously minimizing pressures, enhancing resilience to extreme events, and maximizing cobenefits. The benefits of sustainable urban water solutions for linked urban ecosystems, economies, and arrangements for environmental justice and social equity, will be discussed. The network encompasses six U.S. regions with varying ecohydrologic and climatic regimes ranging from the coastal moist mid-latitude climates of the Mid-Atlantic to the subtropical semi-arid deserts of the Southwest. These regions also represent a wide spectrum of demographic, cultural, and policy settings. The opportunities for cross-site assessments that facilitate the exploration of locally appropriate solutions across regions undergoing various development trajectories will be discussed.

  4. Ultrasonic Sensors in Urban Traffic Driving-Aid Systems

    Directory of Open Access Journals (Sweden)

    Teresa de Pedro

    2011-01-01

    Full Text Available Currently, vehicles are often equipped with active safety systems to reduce the risk of accidents, most of which occur in urban environments. The most prominent include Antilock Braking Systems (ABS, Traction Control and Stability Control. All these systems use different kinds of sensors to constantly monitor the conditions of the vehicle, and act in an emergency. In this paper the use of ultrasonic sensors in active safety systems for urban traffic is proposed, and the advantages and disadvantages when compared to other sensors are discussed. Adaptive Cruise Control (ACC for urban traffic based on ultrasounds is presented as an application example. The proposed system has been implemented in a fully-automated prototype vehicle and has been tested under real traffic conditions. The results confirm the good performance of ultrasonic sensors in these systems.

  5. Ultrasonic sensors in urban traffic driving-aid systems.

    Science.gov (United States)

    Alonso, Luciano; Milanés, Vicente; Torre-Ferrero, Carlos; Godoy, Jorge; Oria, Juan P; de Pedro, Teresa

    2011-01-01

    Currently, vehicles are often equipped with active safety systems to reduce the risk of accidents, most of which occur in urban environments. The most prominent include Antilock Braking Systems (ABS), Traction Control and Stability Control. All these systems use different kinds of sensors to constantly monitor the conditions of the vehicle, and act in an emergency. In this paper the use of ultrasonic sensors in active safety systems for urban traffic is proposed, and the advantages and disadvantages when compared to other sensors are discussed. Adaptive Cruise Control (ACC) for urban traffic based on ultrasounds is presented as an application example. The proposed system has been implemented in a fully-automated prototype vehicle and has been tested under real traffic conditions. The results confirm the good performance of ultrasonic sensors in these systems.

  6. Involving Extension in Urban Food Systems: An Example from California

    Directory of Open Access Journals (Sweden)

    Lucy Diekmann

    2017-06-01

    Full Text Available Nationwide, Extension is increasingly involved in local food system work. In cities, initiatives to improve the local food system often include urban agriculture, which has attracted the attention of diverse stakeholders for its many potential social, health, economic, and environmental impacts. This article illustrates how Extension in the San Francisco Bay Area is developing urban agriculture programming and engaging in food-system-related partnerships. It also shares lessons learned from these efforts. In this metropolitan region, Extension practice aligns well with research findings on Extension involvement in local food systems, particularly with the emphasis on providing educational opportunities and resources adapted to unique needs of city residents and working collaboratively with community and government partners to facilitate broader food system change. The results of this case study will be useful for Extension personnel in designing and implementing programs related to urban food systems.

  7. Development of European urban tourist systems

    Directory of Open Access Journals (Sweden)

    Jerković Senta

    2009-01-01

    Full Text Available Relationship between urban development and tourism is a significant process in Europe today. Development of tourism has caused many organizational changes in urban environment. In the middle of the 20th century cultural and historical heritage in the cities was impetus of development of tourism in European cities. Nowadays, in many European cities tourism is recognized as a mean of further economic development. Strategy of polycentricity, outlined in European spatial development perspective is supporting that process, too. Many tourist centres and metropolitan tourist areas have been developed. In the period from 1996. to 2007. number of visitors in European cultural capitals was growing continuously by rate of 25,6%. In the same period, the number of international tourist arrivals increased by rate of only 7%.

  8. Self-organizing amyloid in bacteria

    DEFF Research Database (Denmark)

    Otzen, D. E.; Vad, B. S.; Dueholm, M. S.

    2017-01-01

    Real biological membranes are complex multi-component systems which are not easily subjected to systematic investigations, although e.g. the dynamics of light-induced structural reorganizations of thylakoid membranes in chloroplast organelles have been studied using time-resolved small-angle neut...

  9. Thought analysis on self-organization theories of MHD plasma

    International Nuclear Information System (INIS)

    Kondoh, Yoshiomi; Sato, Tetsuya.

    1992-08-01

    A thought analysis on the self-organization theories of dissipative MHD plasma is presented to lead to three groups of theories that lead to the same relaxed state of ∇ x B = λB, in order to find an essential physical picture embedded in the self-organization phenomena due to nonlinear and dissipative processes. The self-organized relaxed state due to the dissipation by the Ohm loss is shown to be formulated generally as the state such that yields the minimum dissipation rate of global auto-and/or cross-correlations between two quantities in j, B, and A for their own instantaneous values of the global correlations. (author)

  10. Self-organization of physical fields and spin

    International Nuclear Information System (INIS)

    Pestov, I.B.

    2008-01-01

    The subject of the present investigation is the laws of intrinsic self-organization of fundamental physical fields. In the framework of the Theory of Self-Organization the geometrical and physical nature of spin phenomena is uncovered. The key points are spin symmetry (the fundamental realization of the concept of geometrical internal symmetry) and the spinning field (space of defining representation of spin symmetry). It is shown that the essence of spin is the bipolar structure of spin symmetry induced by the gravitational potentials. The bipolar structure provides natural violation of spin symmetry and leads to spinstatics (theory of spinning field outside the time) and spindynamics. The equations of spinstatics and spindynamics are derived. It is shown that Sommerfeld's formula can be derived from the equations of spindynamics and hence the correspondence principle is valid. This means that the Theory of Self-Organization provides the new understanding of spin phenomena

  11. Self-Organized Construction with Continuous Building Material

    DEFF Research Database (Denmark)

    Heinrich, Mary Katherine; Wahby, Mostafa; Divband Soorati, Mohammad

    2016-01-01

    Self-organized construction with continuous, structured building material, as opposed to modular units, offers new challenges to the robot-based construction process and lends the opportunity for increased flexibility in constructed artifact properties, such as shape and deformation. As an example...... investigation, we look at continuous filaments organized into braided structures, within the context of bio-hybrids constructing architectural artifacts. We report the result of an early swarm robot experiment. The robots successfully constructed a braid in a self-organized process. The construction process can...... be extended by using different materials and by embedding sensors during the self-organized construction directly into the braided structure. In future work, we plan to apply dedicated braiding robot hardware and to construct sophisticated 3-d structures with local variability in patterns of filament...

  12. Co-operation and Self-Organization

    Directory of Open Access Journals (Sweden)

    Christian Fuchs

    2008-07-01

    Full Text Available Co-operation has its specific meanings in physical (dissipative, biological (autopoietic and social (re-creative systems. On upper hierarchical systemic levels there are additional, emergent properties of co-operation, co-operation evolves dialectically. The focus of this paper is human cooperation. Social systems permanently reproduce themselves in a loop that mutually connects social structures and actors. Social structures enable and constrain actions, they are medium and outcome of social actions. This reflexive process is termed re-creation and describes the process of social selforganization. Co-operation in a very weak sense means coaction and takes place permanently in re-creative systems: two or more actors act together in a co-ordinated manner so that a new emergent property emerges. Co-action involves the formation of forces, environment and sense (dispositions, decisions, definitions. Mechanistic approaches conceive coaction in terms of rational planning, consciousness, intention, predictability, and necessity. Holistic approaches conceive coaction in terms of spontaneity, unconscious and unintended actions, non-predictability, chance. Dialectic approaches conceive co-action in terms of a unity of rational planning and spontaneous emergence, a unity of conscious and unconscious aspects and consequences, and a unity of necessity and chance. Co-operation in a strong sense that is employed in this paper means that actors work together, create a new emergent reality, have shared goals, all benefit from co-operating, can reach their goals in joint effort more quickly and more efficiently than on an individual basis, make concerted use of existing structures in order to produce new structures, learn from each other mutually, are interconnected in a social network, and are mutually dependent and responsible. There is a lack of cooperation, self-determination, inclusion and direct democracy in modern society due to its antagonistic

  13. Intelligent Machine Vision for Automated Fence Intruder Detection Using Self-organizing Map

    OpenAIRE

    Veldin A. Talorete Jr.; Sherwin A Guirnaldo

    2017-01-01

    This paper presents an intelligent machine vision for automated fence intruder detection. A series of still captured images that contain fence events using Internet Protocol cameras was used as input data to the system. Two classifiers were used; the first is to classify human posture and the second one will classify intruder location. The system classifiers were implemented using Self-Organizing Map after the implementation of several image segmentation processes. The human posture classifie...

  14. A Review of Sustainable Urban Drainage Systems Considering the Climate Change and Urbanization Impacts

    Directory of Open Access Journals (Sweden)

    Qianqian Zhou

    2014-04-01

    Full Text Available Climate change and urbanization are converging to challenge city drainage infrastructure due to their adverse impacts on precipitation extremes and the environment of urban areas. Sustainable drainage systems have gained growing public interest in recent years, as a result of its positive effects on water quality and quantity issues and additional recreational amenities perceived in the urban landscape. This paper reviews recent progress in sustainable drainage development based on literature across different disciplinary fields. After presenting the key elements and criteria of sustainable drainage design, various devices and examples of sustainable drainage systems are introduced. The state-of-the-art model approaches and decision-aid tools for assessing the sustainable alternatives are discussed and compared. The paper further explores some limitations and difficulties in the application of the innovative solutions and suggests an integrated and trans-disciplinary approach for sustainable drainage design.

  15. Integrated management of water resources in urban water system: Water Sensitive Urban Development as a strategic approach

    Directory of Open Access Journals (Sweden)

    Juan Joaquín Suárez López

    2014-08-01

    Full Text Available The urban environment has to be concerned with the integrated water resources management, which necessarily includes the concept of basin unity and governance.  The traditional urban water cycle framework, which includes water supply, sewerage and wastewater treatment services, is being replaced by a holistic and systemic concept, where water is associated with urbanism and sustainability policies. This global point of view cannot be ignored as new regulations demand systemic and environmental approaches to the administrations, for instance, in the management of urban drainage and sewerage systems. The practical expression of this whole cluster interactions is beginning to take shape in several countries, with the definition of Low Impact Development and Water Sensitivity Urban Design concepts. Intends to integrate this new strategic approach under the name: “Water Sensitive Urban Development” (WSUD. With WSUD approach, the current urban water systems (originally conceived under the traditional concept of urban water cycle can be transformed, conceptual and physically, for an integrated management of the urban water system in new models of sustainable urban development. A WSUD implementing new approach to the management of pollution associated with stormwater in the urban water system is also presented, including advances in environmental regulations and incorporation of several techniques in Spain.

  16. Self-Organizing Map Models of Language Acquisition

    Directory of Open Access Journals (Sweden)

    Ping eLi

    2013-11-01

    Full Text Available Connectionist models have had a profound impact on theories of language. While most early models were inspired by the classic PDP architecture, recent models of language have explored various other types of models, including self-organizing models for language acquisition. In this paper we aim at providing a review of the latter type of models, and highlight a number of simulation experiments that we have conducted based on these models. We show that self-organizing connectionist models can provide significant insights into long-standing debates in both monolingual and bilingual language development.

  17. Unsupervised learning via self-organization a dynamic approach

    CERN Document Server

    Kyan, Matthew; Jarrah, Kambiz; Guan, Ling

    2014-01-01

    To aid in intelligent data mining, this book introduces a new family of unsupervised algorithms that have a basis in self-organization, yet are free from many of the constraints typical of other well known self-organizing architectures. It then moves through a series of pertinent real world applications with regards to the processing of multimedia data from its role in generic image processing techniques such as the automated modeling and removal of impulse noise in digital images, to problems in digital asset management, and its various roles in feature extraction, visual enhancement, segmentation, and analysis of microbiological image data.

  18. TWO CHANNELS OF SELF-ORGANIZATION OF IONIZED GASEOUS MEDIA

    Directory of Open Access Journals (Sweden)

    Benedict Oprescu

    2013-12-01

    Full Text Available The appearance is pointed out, experimentally, of a complex electric charge structure, within an ionized gas, relatively homogeneous at first, under the influence of a number of external constraints. Two different mechanisms of self-organization are presented: the former implying, essentially, long-range interactions, and the latter implying, essentially, short-range quantum interactions. The phenomenological scenarios are presented, which underlie the two mechanisms of self-organization, as well as the broader theoretical frame, currently accepted, concerning the generation of complexity in the material media that are far from the state of thermodynamic equilibrium.

  19. Exponential Self-Organization and Moore’s Law: Measures and Mechanisms

    Directory of Open Access Journals (Sweden)

    Georgi Yordanov Georgiev

    2017-01-01

    Full Text Available The question of how complex systems become more organized and efficient with time is open. Examples are the formation of elementary particles from pure energy, the formation of atoms from particles, the formation of stars and galaxies, and the formation of molecules from atoms, of organisms, and of the society. In this sequence, order appears inside complex systems and randomness (entropy is expelled to their surroundings. Key features of self-organizing systems are that they are open and they are far away from equilibrium, with increasing energy flows through them. This work searches for global measures of such self-organizing systems, which are predictable and do not depend on the substrate of the system studied. Our results will help to understand the existence of complex systems and mechanisms of self-organization. In part we also provide insights, in this work, about the underlying physical essence of Moore’s law and the multiple logistic growth observed in technological progress.

  20. On the self-organized critical state of Vesuvio volcano

    Science.gov (United States)

    Luongo, G.; Mazzarella, A.; Palumbo, A.

    1996-01-01

    The catalogue of volcanic earthquakes recorded at Vesuvio (1972-1993) is shown to be complete for events with magnitude enclosed between 1.8 and 3.0. Such a result is converted in significant fractal laws (power laws) relating the distribution of earthquakes to the distribution of energy release, seismic moment, size of fractured zone and linear dimension of faults. The application of the Cantor dust model to time sequence of Vesuvio seismic and eruptive events allows the determination of significant time-clustering fractal structures. In particular, the Vesuvio eruptive activity shows a double-regime process with a stronger clustering on short-time scales than on long-time scales. The complexity of the Vesuvio system does not depend on the number of geological, geophysical and geochemical factors that govern it, but mainly on the number of their interconnections, on the intensity of such linkages and on the feed-back processes. So, all the identified fractal features are taken as evidence that the Vesuvio system is in a self-organized critical state i.e., in a marginally stable state in which a small perturbation can start a chain reaction that can lead to catastrophe. After the catatrophe, the system regulates itself and begins a new cycle, not necessarily periodic, that will end with a successive catastrophe. The variations of the fractal dimension and of the specific scale ranges, in which the fractal behaviour is found to hold, serve as possible volcanic predictors reflecting changes of the same volcanic process.

  1. Self-organization and atomic nuclei

    International Nuclear Information System (INIS)

    Rotter, I.

    1988-01-01

    The transition from the resonance reaction mechanism at low level density to the direct reaction mechanism at high level density is investigated by means of numerical results obtained from microscopic calculations for nucleon induced reactions. The transition takes place rather sharply at approx . Here, two types of motion of the nucleons exist simultaneously: a motion in long-living states which are near equilibrium and a motion in short-living states which are far from equilibrium. A formation of order out of chaos takes place only in the open quantum mechanical nuclear system. It is caused by the quantum fluctuations via the continuum

  2. Determinism, chaos, self-organization and entropy

    Directory of Open Access Journals (Sweden)

    JOSÉ PONTES

    2016-06-01

    Full Text Available ABSTRACT We discuss two changes of paradigms that occurred in science along the XXth century: the end of the mechanist determinism, and the end of the apparent incompatibility between biology, where emergence of order is law, and physics, postulating a progressive loss of order in natural systems. We recognize today that three mechanisms play a major role in the building of order: the nonlinear nature of most evolution laws, along with distance to equilibrium, and with the new paradigm, that emerged in the last forty years, as we recognize that networks present collective order properties not found in the individual nodes. We also address the result presented by Blumenfeld (L.A. Blumenfeld, Problems of Biological Physics, Springer, Berlin, 1981 showing that entropy decreases resulting from building one of the most complex biological structures, the human being, are small and may be trivially compensated for compliance with thermodynamics. Life is made at the expense of very low thermodynamic cost, so thermodynamics does not pose major restrictions to the emergence of life. Besides, entropy does not capture our idea of order in biological systems. The above questions show that science is not free of confl icts and backlashes, often resulting from excessive extrapolations.

  3. Determinism, chaos, self-organization and entropy.

    Science.gov (United States)

    Pontes, José

    2016-01-01

    We discuss two changes of paradigms that occurred in science along the XXth century: the end of the mechanist determinism, and the end of the apparent incompatibility between biology, where emergence of order is law, and physics, postulating a progressive loss of order in natural systems. We recognize today that three mechanisms play a major role in the building of order: the nonlinear nature of most evolution laws, along with distance to equilibrium, and with the new paradigm, that emerged in the last forty years, as we recognize that networks present collective order properties not found in the individual nodes. We also address the result presented by Blumenfeld (L.A. Blumenfeld, Problems of Biological Physics, Springer, Berlin, 1981) showing that entropy decreases resulting from building one of the most complex biological structures, the human being, are small and may be trivially compensated for compliance with thermodynamics. Life is made at the expense of very low thermodynamic cost, so thermodynamics does not pose major restrictions to the emergence of life. Besides, entropy does not capture our idea of order in biological systems. The above questions show that science is not free of confl icts and backlashes, often resulting from excessive extrapolations.

  4. Optimal energy management of urban rail systems: Key performance indicators

    International Nuclear Information System (INIS)

    González-Gil, A.; Palacin, R.; Batty, P.

    2015-01-01

    Highlights: • An overall picture of urban rail energy use is provided. • Performance indicators are developed for urban rail system energy optimisation. • A multi-level methodology for assessing energy efficiency measures is presented. - Abstract: Urban rail systems are facing increasing pressure to minimise their energy consumption and thusly reduce their operational costs and environmental impact. However, given the complexity of such systems, this can only be effectively achieved through a holistic approach which considers the numerous interdependences between subsystems (i.e. vehicles, operations and infrastructure). Such an approach requires a comprehensive set of energy consumption-related Key Performance Indicators (KEPIs) that enable: a multilevel analysis of the actual energy performance of the system; an assessment of potential energy saving strategies; and the monitoring of the results of implemented measures. This paper proposes an original, complete list of KEPIs developed through a scientific approach validated by different stakeholders. It consists of a hierarchical list of 22 indicators divided into two levels: 10 key performance indicators, to ascertain the performance of the whole system and complete subsystems; and 12 performance indicators, to evaluate the performance of single units within subsystems, for example, a single rail vehicle or station. Additionally, the paper gives a brief insight into urban rail energy usage by providing an adequate context in which to understand the proposed KEPIs, together with a methodology describing their application when optimising the energy consumption of urban rail systems

  5. Developing Efficient Urban Electrical Systems Using Microgrids

    Energy Technology Data Exchange (ETDEWEB)

    Gahagan, Michael

    2010-09-15

    Electric vehicles and battery storage will complicate utility operations and strain existing networks. One possible solution is the implementation of 'microgrids' autonomous electricity environments that operate within a larger electric utility grid and their 'controllers' Microgrids direct locally generated power to local demand, coordinate with centralized utility networks to meet additional demand, and pass excess supply to neighboring microgrids. This paper explains the evolution of microgrids. It details their design and operation. It also reviews their many benefits within urban settings, including minimizing customer costs while maximizing use of local generation from clean, renewable resources.

  6. Hierarchical self-organization of non-cooperating individuals.

    Directory of Open Access Journals (Sweden)

    Tamás Nepusz

    Full Text Available Hierarchy is one of the most conspicuous features of numerous natural, technological and social systems. The underlying structures are typically complex and their most relevant organizational principle is the ordering of the ties among the units they are made of according to a network displaying hierarchical features. In spite of the abundant presence of hierarchy no quantitative theoretical interpretation of the origins of a multi-level, knowledge-based social network exists. Here we introduce an approach which is capable of reproducing the emergence of a multi-levelled network structure based on the plausible assumption that the individuals (representing the nodes of the network can make the right estimate about the state of their changing environment to a varying degree. Our model accounts for a fundamental feature of knowledge-based organizations: the less capable individuals tend to follow those who are better at solving the problems they all face. We find that relatively simple rules lead to hierarchical self-organization and the specific structures we obtain possess the two, perhaps most important features of complex systems: a simultaneous presence of adaptability and stability. In addition, the performance (success score of the emerging networks is significantly higher than the average expected score of the individuals without letting them copy the decisions of the others. The results of our calculations are in agreement with a related experiment and can be useful from the point of designing the optimal conditions for constructing a given complex social structure as well as understanding the hierarchical organization of such biological structures of major importance as the regulatory pathways or the dynamics of neural networks.

  7. 25 Years of Self-organized Criticality: Concepts and Controversies

    Science.gov (United States)

    Watkins, Nicholas W.; Pruessner, Gunnar; Chapman, Sandra C.; Crosby, Norma B.; Jensen, Henrik J.

    2016-01-01

    Introduced by the late Per Bak and his colleagues, self-organized criticality (SOC) has been one of the most stimulating concepts to come out of statistical mechanics and condensed matter theory in the last few decades, and has played a significant role in the development of complexity science. SOC, and more generally fractals and power laws, have attracted much comment, ranging from the very positive to the polemical. The other papers (Aschwanden et al. in Space Sci. Rev., 2014, this issue; McAteer et al. in Space Sci. Rev., 2015, this issue; Sharma et al. in Space Sci. Rev. 2015, in preparation) in this special issue showcase the considerable body of observations in solar, magnetospheric and fusion plasma inspired by the SOC idea, and expose the fertile role the new paradigm has played in approaches to modeling and understanding multiscale plasma instabilities. This very broad impact, and the necessary process of adapting a scientific hypothesis to the conditions of a given physical system, has meant that SOC as studied in these fields has sometimes differed significantly from the definition originally given by its creators. In Bak's own field of theoretical physics there are significant observational and theoretical open questions, even 25 years on (Pruessner 2012). One aim of the present review is to address the dichotomy between the great reception SOC has received in some areas, and its shortcomings, as they became manifest in the controversies it triggered. Our article tries to clear up what we think are misunderstandings of SOC in fields more remote from its origins in statistical mechanics, condensed matter and dynamical systems by revisiting Bak, Tang and Wiesenfeld's original papers.

  8. Self-Organized Complexity and Coherent Infomax from the Viewpoint of Jaynes’s Probability Theory

    Directory of Open Access Journals (Sweden)

    William A. Phillips

    2012-01-01

    Full Text Available This paper discusses concepts of self-organized complexity and the theory of Coherent Infomax in the light of Jaynes’s probability theory. Coherent Infomax, shows, in principle, how adaptively self-organized complexity can be preserved and improved by using probabilistic inference that is context-sensitive. It argues that neural systems do this by combining local reliability with flexible, holistic, context-sensitivity. Jaynes argued that the logic of probabilistic inference shows it to be based upon Bayesian and Maximum Entropy methods or special cases of them. He presented his probability theory as the logic of science; here it is considered as the logic of life. It is concluded that the theory of Coherent Infomax specifies a general objective for probabilistic inference, and that contextual interactions in neural systems perform functions required of the scientist within Jaynes’s theory.

  9. Self-organization processes and nanocluster formation in crystal lattices by low-energy ion irradiation

    International Nuclear Information System (INIS)

    Tereshko, I.; Abidzina, V.; Tereshko, A.; Glushchenko, V.; Elkin, I.

    2007-01-01

    The goal of this paper is to study self-organization processes that cause nanostructural evolution in nonlinear crystal media. The subjects of the investigation were nonlinear homogeneous and heterogeneous atom chains. The method of computer simulation was used to investigate the interaction between low-energy ions and crystal lattices. It was based on the conception of three-dimensional lattice as a nonlinear atom chain system. We showed that that in homogeneous atom chains critical energy needed for self-organization processes development is less than for nonlinear atom chain with already embedded clusters. The possibility of nanostructure formation was studied by a molecular dynamics method of nonlinear oscillations in atomic oscillator systems of crystal lattices after their low-energy ion irradiation. (authors)

  10. On Origin of Power-Law Distributions in Self-Organized Criticality from Random Walk Treatment

    International Nuclear Information System (INIS)

    Cao Xiaofeng; Deng Zongwei; Yang Chunbin

    2008-01-01

    The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random walk process in a one-dimensional lattice. We assume that the variation of the number of active sites has three possibilities in each update: to increase by 1 with probability f 1 , to decrease by 1 with probability f 2 , or remain unchanged with probability 1-f 1 -f 2 . This mimics the dynamics in the system. Power-law distributions of the lifetime are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions.

  11. Internal structures of self-organized relaxed states and self-similar decay phase

    International Nuclear Information System (INIS)

    Kondoh, Yoshiomi

    1992-03-01

    A thought analysis on relaxation due to nonlinear processes is presented to lead to a set of general thoughts applicable to general nonlinear dynamical systems for finding out internal structures of the self-organized relaxed state without using 'invariant'. Three applications of the set of general thoughts to energy relaxations in resistive MHD plasmas, incompressible viscous fluids, and incompressible viscous MHD fluids are shown to lead to the internal structures of the self-organized relaxed states. It is shown that all of the relaxed states in these three dynamical systems are followed by self-similar decay phase without significant change of the spatial structure. The well known relaxed state of ∇ x B = ±λ B is shown to be derived generally in the low β plasma limit. (author)

  12. Vulnerability Analysis of Urban Drainage Systems: Tree vs. Loop Networks

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2017-03-01

    Full Text Available Vulnerability analysis of urban drainage networks plays an important role in urban flood management. This study analyzes and compares the vulnerability of tree and loop systems under various rainfall events to structural failure represented by pipe blockage. Different pipe blockage scenarios, in which one of the pipes in an urban drainage network is assumed to be blocked individually, are constructed and their impacts on the network are simulated under different storm events. Furthermore, a vulnerability index is defined to measure the vulnerability of the drainage systems before and after the implementation of adaptation measures. The results obtained indicate that the tree systems have a relatively larger proportion of critical hydraulic pipes than the loop systems, thus the vulnerability of tree systems is substantially greater than that of the loop systems. Furthermore, the vulnerability index of tree systems is reduced after they are converted into a loop system with the implementation of adaptation measures. This paper provides an insight into the differences in the vulnerability of tree and loop systems, and provides more evidence for development of adaptation measures (e.g., tanks to reduce urban flooding.

  13. Discerning Thermodynamic Basis of Self-Organization in Critical Zone Structure and Function

    Science.gov (United States)

    Richardson, M.; Kumar, P.

    2017-12-01

    Self-organization characterizes the spontaneous emergence of order. Self-organization in the Critical Zone, the region of Earth's skin from below the groundwater table to the top of the vegetation canopy, involves the interaction of biotic and abiotic processes occurring through a hierarchy of temporal and spatial scales. The self-organization is sustained through input of energy and material in an open system framework, and the resulting formations are called dissipative structures. Why do these local states of organization form and how are they thermodynamically favorable? We hypothesize that structure formation is linked to energy conversion and matter throughput rates across driving gradients. Furthermore, we predict that structures in the Critical Zone evolve based on local availability of nutrients, water, and energy. By considering ecosystems as open thermodynamic systems, we model and study the throughput signatures on short times scales to determine origins and characteristics of ecosystem structure. This diagnostic approach allows us to use fluxes of matter and energy to understand the thermodynamic drivers of the system. By classifying the fluxes and dynamics in a system, we can identify patterns to determine the thermodynamic drivers for organized states. Additionally, studying the partitioning of nutrients, water, and energy throughout ecosystems through dissipative structures will help identify reasons for structure shapes and how these shapes impact major Critical Zone functions.

  14. Self-Organization and Annealed Disorder in a Fracturing Process

    DEFF Research Database (Denmark)

    Caldarelli, Guido; Di Tolla, Francesco; Petri, Alberto

    1996-01-01

    We show that a vectorial model for inhomogeneous elastic media self-organizes under external stress. An onset of crack avalanches of every duration and length scale compatible with the lattice size is observed. The behavior is driven by the introduction of annealed disorder, i.e., by lowering...... condition for reproducing the algebraic distribution of the energy released during cracks formation....

  15. Comparative investigation of two different self-organizing map ...

    African Journals Online (AJOL)

    Purpose: To demonstrate the ability and investigate the performance of two different wavelength selection approaches based on self-organizing map (SOM) technique in partial least-squares (PLS) regression for analysis of pharmaceutical binary mixtures with strongly overlapping spectra. Methods: Two different variable ...

  16. Self-organized criticality in a network of interacting neurons

    NARCIS (Netherlands)

    Cowan, J.D.; Neuman, J.; Kiewiet, B.; van Drongelen, W.

    2013-01-01

    This paper contains an analysis of a simple neural network that exhibits self-organized criticality. Such criticality follows from the combination of a simple neural network with an excitatory feedback loop that generates bistability, in combination with an anti-Hebbian synapse in its input pathway.

  17. Self-organization as a possible route to fusion energy

    International Nuclear Information System (INIS)

    Sanduloviciu, M.; Lozneanu, E.; Popescu, S.

    2000-01-01

    The generation of a ball lightning-like complex structure by sudden injection of matter and energy proves the presence of a cascading self-organization scenario in an experimental device containing a collisional plasma. Based on these results, we suggest the possibility to replicate, under controlled laboratory conditions, the ball lightning-like structures with potential fusion applications. (author)

  18. Gaining insight in domestic violence with emergent self organizing maps

    NARCIS (Netherlands)

    Poelmans, J.; Elzinga, P.; Viaene, S.; van Hulle, M.M.; Dedene, G.

    2009-01-01

    Topographic maps are an appealing exploratory instrument for discovering new knowledge from databases. During the past years, new types of Self Organizing Maps (SOM) were introduced in the literature, including the recent Emergent SOM. The ESOM tool is used here to analyze a large set of police

  19. Urban Typologies: Towards an ORNL Urban Information System (UrbIS)

    Science.gov (United States)

    KC, B.; King, A. W.; Sorokine, A.; Crow, M. C.; Devarakonda, R.; Hilbert, N. L.; Karthik, R.; Patlolla, D.; Surendran Nair, S.

    2016-12-01

    Urban environments differ in a large number of key attributes; these include infrastructure, morphology, demography, and economic and social variables, among others. These attributes determine many urban properties such as energy and water consumption, greenhouse gas emissions, air quality, public health, sustainability, and vulnerability and resilience to climate change. Characterization of urban environments by a single property such as population size does not sufficiently capture this complexity. In addressing this multivariate complexity one typically faces such problems as disparate and scattered data, challenges of big data management, spatial searching, insufficient computational capacity for data-driven analysis and modelling, and the lack of tools to quickly visualize the data and compare the analytical results across different cities and regions. We have begun the development of an Urban Information System (UrbIS) to address these issues, one that embraces the multivariate "big data" of urban areas and their environments across the United States utilizing the Big Data as a Service (BDaaS) concept. With technological roots in High-performance Computing (HPC), BDaaS is based on the idea of outsourcing computations to different computing paradigms, scalable to super-computers. UrbIS aims to incorporate federated metadata search, integrated modeling and analysis, and geovisualization into a single seamless workflow. The system includes web-based 2D/3D visualization with an iGlobe interface, fast cloud-based and server-side data processing and analysis, and a metadata search engine based on the Mercury data search system developed at Oak Ridge National Laboratory (ORNL). Results of analyses will be made available through web services. We are implementing UrbIS in ORNL's Compute and Data Environment for Science (CADES) and are leveraging ORNL experience in complex data and geospatial projects. The development of UrbIS is being guided by an investigation of

  20. Crossover to self-organized criticality in an inertial sandpile model

    OpenAIRE

    Head, DA; Rodgers, GJ

    1996-01-01

    We introduce a one-dimensional sandpile model which incorporates particle inertia. The inertial dynamics are governed by a new parameter which, as it passes through a threshold value, alters the toppling dynamics in such a way that the system no longer evolves to a self-organized critical state. A range of mean-field theories based on a kinetic equation approach is presented which confirm the numerical findings. We conclude by considering the physical applications of this model, particularly ...

  1. Sustainable urban systems: Co-design and framing for transformation.

    Science.gov (United States)

    Webb, Robert; Bai, Xuemei; Smith, Mark Stafford; Costanza, Robert; Griggs, David; Moglia, Magnus; Neuman, Michael; Newman, Peter; Newton, Peter; Norman, Barbara; Ryan, Chris; Schandl, Heinz; Steffen, Will; Tapper, Nigel; Thomson, Giles

    2018-02-01

    Rapid urbanisation generates risks and opportunities for sustainable development. Urban policy and decision makers are challenged by the complexity of cities as social-ecological-technical systems. Consequently there is an increasing need for collaborative knowledge development that supports a whole-of-system view, and transformational change at multiple scales. Such holistic urban approaches are rare in practice. A co-design process involving researchers, practitioners and other stakeholders, has progressed such an approach in the Australian context, aiming to also contribute to international knowledge development and sharing. This process has generated three outputs: (1) a shared framework to support more systematic knowledge development and use, (2) identification of barriers that create a gap between stated urban goals and actual practice, and (3) identification of strategic focal areas to address this gap. Developing integrated strategies at broader urban scales is seen as the most pressing need. The knowledge framework adopts a systems perspective that incorporates the many urban trade-offs and synergies revealed by a systems view. Broader implications are drawn for policy and decision makers, for researchers and for a shared forward agenda.

  2. Greenhouse gas emissions from integrated urban drainage systems

    DEFF Research Database (Denmark)

    Mannina, Giorgio; Butler, David; Benedetti, Lorenzo

    2018-01-01

    As sources of greenhouse gas (GHG) emissions, integrated urban drainage systems (IUDSs) (i.e., sewer systems, wastewater treatment plants and receiving water bodies) contribute to climate change. This paper, produced by the International Working Group on Data and Models, which works under the IWA...

  3. A Multilayer perspective for the analysis of urban transportation systems.

    Science.gov (United States)

    Aleta, Alberto; Meloni, Sandro; Moreno, Yamir

    2017-03-15

    Public urban mobility systems are composed by several transportation modes connected together. Most studies in urban mobility and planning often ignore the multi-layer nature of transportation systems considering only aggregated versions of this complex scenario. In this work we present a model for the representation of the transportation system of an entire city as a multiplex network. Using two different perspectives, one in which each line is a layer and one in which lines of the same transportation mode are grouped together, we study the interconnected structure of 9 different cities in Europe raging from small towns to mega-cities like London and Berlin highlighting their vulnerabilities and possible improvements. Finally, for the city of Zaragoza in Spain, we also consider data about service schedule and waiting times, which allow us to create a simple yet realistic model for urban mobility able to reproduce real-world facts and to test for network improvements.

  4. On the nature and shape of tubulin trails: implications on microtubule self-organization.

    Science.gov (United States)

    Glade, Nicolas

    2012-06-01

    Microtubules, major elements of the cell skeleton are, most of the time, well organized in vivo, but they can also show self-organizing behaviors in time and/or space in purified solutions in vitro. Theoretical studies and models based on the concepts of collective dynamics in complex systems, reaction-diffusion processes and emergent phenomena were proposed to explain some of these behaviors. In the particular case of microtubule spatial self-organization, it has been advanced that microtubules could behave like ants, self-organizing by 'talking to each other' by way of hypothetic (because never observed) concentrated chemical trails of tubulin that are expected to be released by their disassembling ends. Deterministic models based on this idea yielded indeed like-looking spatio-temporal self-organizing behaviors. Nevertheless the question remains of whether microscopic tubulin trails produced by individual or bundles of several microtubules are intense enough to allow microtubule self-organization at a macroscopic level. In the present work, by simulating the diffusion of tubulin in microtubule solutions at the microscopic scale, we measure the shape and intensity of tubulin trails and discuss about the assumption of microtubule self-organization due to the production of chemical trails by disassembling microtubules. We show that the tubulin trails produced by individual microtubules or small microtubule arrays are very weak and not elongated even at very high reactive rates. Although the variations of concentration due to such trails are not significant compared to natural fluctuations of the concentration of tubuline in the chemical environment, the study shows that heterogeneities of biochemical composition can form due to microtubule disassembly. They could become significant when produced by numerous microtubule ends located in the same place. Their possible formation could play a role in certain conditions of reaction. In particular, it gives a mesoscopic

  5. Indicating anthropogenic effectson urban water system - indicators and extension

    Science.gov (United States)

    Strauch, G.; Ufz-Team

    2003-04-01

    Urban water systems are polluted by diffusive and direct contribution of anthropogenic activities. Besides industrial contaminants like aromatic and chlorinated HC and other persistent organic compounds, the urban aquatic environment is increasingly polluted by low concentrated but high eco-toxic compounds as pharmaceuticals, fragrances, plasticizers which most have disrupt endocrine functions, and trace elements carried in by surface and sub-surface waste water and seeping processes. This contamination could have a longtime impact on the urban ecosystem and on the human health. The interdisciplinary project on risk assessment of water pollution was initiated to explore new methodologies for assessing human activities on the urban water system and processes among urban watersheds. In a first assumption we used a flow model concept with in- and output and surface water transport represented by the city of Halle, Germany, and the river Saale. The river Saale acts as surface water system collecting waste water inputs along the city traverse. We investigated the anthropogenic effect on the urban water system using the indicators hydrological parameters, compound specific pattern of complex organic substances and trace elements, isotopic signatures of water (H, O) and dissolved substances (sulfate, DIC, nitrate), pathogens, and microbiota. A first balance modeling showed that main ions are not very sensitive concerning the direct urban input into the river. Depending on the discharge of the river in high and low flood stages the load of dissolved matter has no specific urban effect. However, the concentration pattern of fragrances (tonalid, galaxolid) and endocrine disrupters (t-nonylphenol) point to a different pollution along the city traverse: downstream of the sewage plant a higher load was observed in comparison to the upstream passage. Furthermore, a degradation ability of fungi and bacteria occurred in the bank sediments could be detected in lab experiments

  6. APPROACHES TO THE ANALYSIS AND EVALUATION OF URBAN TOURISM SYSTEM WITHIN URBAN DESTINATIONS

    Directory of Open Access Journals (Sweden)

    Amalia BĂDIŢĂ

    2013-12-01

    Full Text Available The city is an area that has a complex functionality which is based on the utility of its zones that imprint a quality of life and a specificity to the place, but it is also based on the architectural aesthetics which determines a local lifestyle and a potential which can be exploited through tourist activities. The study aims to identify the characteristics of the urban tourism and the elements of an urban tourism system, which will be approached by identifying the city-breaker profile, the relation between turisticity and urbanity to determine the quality of places. These elements will be applied as a case study in Craiova, a mixed industrial and services economical profile city, with a low tourism function. This type of city has an urban tourism system which starts to take shape, and according to the theory of "overlapping cities" although there are many forms of tourism in a city (cultural, business, shopping, sports tourism, visiting relatives and friends and recreational tourism, Craiova focuses on the typology of the city for festivals, business, leisure and sport, as a strategy for the tourism sector development and for entering the tourism market of Romania.

  7. European practices of providing of efficiency of self-organizations institutions of population in the context of public services

    Directory of Open Access Journals (Sweden)

    T. V. Serohina

    2017-06-01

    Full Text Available The research revealed that European countries devote sufficient attention to ensuring the effectiveness of the institutions of self-organization in the context of their public services. The most common areas where they operate are a system of health, education and assistance during emergencies. The study showed that in the development of public services, there were significant transformations in terms of subject-provider. Historically it was confessional organizations working on a voluntary basis, and linked their activity with the realization of Christian mission. Subsequently, when there had been formation of a «welfare state», the state took over responsibility for the area of public services. In favor of institutions of self-organization has been a change in the system when it became clear that they are best in the provide public services, especially in the social sphere, because they are the demonstrating of social needs. The main mechanisms of cooperation between institutions of self-organization and the public sector are, first, subsidies for statutory activities of the organization. Another mechanism is delegating services or outsourcing and in this case contracts mostly are for one year with possibility of further extension. In addition there is auxiliary element of providing of effectiveness institutions of self-organization, it consists in deprivation of their donors from taxes. Although institutions of self-organization are financed mainly by public authorities, they remain independent, because they have opportunity of funding from other sources. German experience showed that the starting point in the system of public services is the understanding of the necessity of paying taxes as acknowledgment of the rights of all members of society. That is why every taxpayer expects to receive public services at the appropriate level. This unwritten rule contributes to a very high level of provision of public services through an adequate

  8. Spatial self-organization and the production of the city

    Directory of Open Access Journals (Sweden)

    Romulo Krafta

    1999-03-01

    Full Text Available Production of urban space is assumed to be a rent seeking activity, carried out by many developers who are constantly trying to get the best possible assessment of market and spatial features in order to better produce profit. Developers act locally, that is, they can choose their locations from all over the city, although they do not have a perfect foresight. Different urban locations prompt different types of development, e. g. several housing, commercial, industrial types, although each location can support more than one type development. The more structured the city is, the narrower is the type choice; on the contrary, in areas scarcely occupied the degree of freedom and unpredictability is larger. Developers compete to each other for locations where the land price is lower; in fact land is considered the single most important component of the development, in the sense that it is the only one whose price can vary and hence affect the price of the final good. Developers "invent" new locations constantly, by buying cheap land, investing on it and selling the resulting built space at higher prices. As soon as a developer discover a new location, others follow, making the land price to rise and the advantage to disappear. The resulting urban development is uneven and generally unpredictable; however, urban areas can be assessed from the point of view of its stability, or its resistance to change. A model has been tried out, as follows.Urban space is disaggregated in units of public space, each one presenting a certain level of urbanisation (infrastructure and built form, what affords a measure of spatial differentiation. Built form is also distinguished by their typological affiliation, so that the stocks are classified according to categories, precisely the ones taken on by developers. Moreover, stocks are also characterised by vintages, so that their actual market value can be updated after each iteration. The urban system is constituted by a

  9. Enhancement of biomembrane functions under phase-separated conditions: A self-organized criticality phenomenon?

    International Nuclear Information System (INIS)

    Eze, M.O.; Chela Flores, J.

    1993-12-01

    Self-organized criticality (SOC) is hereby proposed as a possible physical basis for explaining observations in the temperature-dependence of the rates of biological membrane-associated events. The biomembrane undergoes a reversible, cooperative, thermotropic gel-to-liquid crystalline phase transition which is broad, and involves lateral phase separation. The lateral phase separated (rather than the totally gel-, or the totally liquid crystalline-) membrane state has been observed to be the state in which vital membrane functions are facilitated. The membrane in this unique state is viewed, for our purposes here, as a dynamical, extended dissipative system with spatial and temporal degrees of freedom, exhibiting power law behaviour, typical of the self-organized critical state. Experiments are suggested for verifying this hypothesis. (author). 30 refs

  10. Clustering of the Self-Organizing Map based Approach in Induction Machine Rotor Faults Diagnostics

    Directory of Open Access Journals (Sweden)

    Ahmed TOUMI

    2009-12-01

    Full Text Available Self-Organizing Maps (SOM is an excellent method of analyzingmultidimensional data. The SOM based classification is attractive, due to itsunsupervised learning and topology preserving properties. In this paper, theperformance of the self-organizing methods is investigated in induction motorrotor fault detection and severity evaluation. The SOM is based on motor currentsignature analysis (MCSA. The agglomerative hierarchical algorithms using theWard’s method is applied to automatically dividing the map into interestinginterpretable groups of map units that correspond to clusters in the input data. Theresults obtained with this approach make it possible to detect a rotor bar fault justdirectly from the visualization results. The system is also able to estimate theextent of rotor faults.

  11. Self-organization of domain growth in the Ising model with impurities

    DEFF Research Database (Denmark)

    Andersen, Jørgen Vitting; Mouritsen, Ole G.

    1992-01-01

    We have studied avalanchelike rearrangements of domain patterns in the two-dimensional Ising model with static impurities, which is quenched to low temperatures. When breaking the up-down symmetry of the spins by a small applied field, the mere fluctuation of a single spin eventually results...... in a cascade of spin flips at the domain boundaries. We have analyzed the lifetime and size distribution functions for the avalanches and related the results to the general phenomena of self-organized criticality and to recent experiments on cellular magnetic domain patterns in magnetic garnet films. Our...... results suggest that the self-organized state in this system appears to be subcritical, in agreement with a recent theory....

  12. The origin of power-law distributions in self-organized criticality

    International Nuclear Information System (INIS)

    Yang, C B

    2004-01-01

    The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random-walk process in a one-dimensional lattice. Power-law distributions of the lifetime and spatial size are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions. At the mean time, the mean spatial size for avalanches with the same lifetime is found to increase in a power law with the lifetime. (letter to the editor)

  13. Interfacial self-organization of bolaamphiphiles bearing mesogenic groups: relationships between the molecular structures and their self-organized morphologies.

    Science.gov (United States)

    Song, Bo; Liu, Guanqing; Xu, Rui; Yin, Shouchun; Wang, Zhiqiang; Zhang, Xi

    2008-04-15

    This article discusses the relationship between the molecular structure of bolaamphiphiles bearing mesogenic groups and their interfacial self-organized morphology. On the basis of the molecular structures of bolaamphiphiles, we designed and synthesized a series of molecules with different hydrophobic alkyl chain lengths, hydrophilic headgroups, mesogenic groups, and connectors between the alkyl chains and the mesogenic group. Through investigating their interfacial self-organization behavior, some experiential rules are summarized: (1) An appropriate alkyl chain length is necessary to form stable surface micelles; (2) different categories of headgroups have a great effect on the interfacial self-organized morphology; (3) different types of mesogenic groups have little effect on the structure of the interfacial assembly when it is changed from biphenyl to azobenzene or stilbene; (4) the orientation of the ester linker between the mesogenic group and alkyl chain can greatly influence the interfacial self-organization behavior. It is anticipated that this line of research may be helpful for the molecular engineering of bolaamphiphiles to form tailor-made morphologies.

  14. Evolutionary Cell Computing: From Protocells to Self-Organized Computing

    Science.gov (United States)

    Colombano, Silvano; New, Michael H.; Pohorille, Andrew; Scargle, Jeffrey; Stassinopoulos, Dimitris; Pearson, Mark; Warren, James

    2000-01-01

    On the path from inanimate to animate matter, a key step was the self-organization of molecules into protocells - the earliest ancestors of contemporary cells. Studies of the properties of protocells and the mechanisms by which they maintained themselves and reproduced are an important part of astrobiology. These studies also have the potential to greatly impact research in nanotechnology and computer science. Previous studies of protocells have focussed on self-replication. In these systems, Darwinian evolution occurs through a series of small alterations to functional molecules whose identities are stored. Protocells, however, may have been incapable of such storage. We hypothesize that under such conditions, the replication of functions and their interrelationships, rather than the precise identities of the functional molecules, is sufficient for survival and evolution. This process is called non-genomic evolution. Recent breakthroughs in experimental protein chemistry have opened the gates for experimental tests of non-genomic evolution. On the basis of these achievements, we have developed a stochastic model for examining the evolutionary potential of non-genomic systems. In this model, the formation and destruction (hydrolysis) of bonds joining amino acids in proteins occur through catalyzed, albeit possibly inefficient, pathways. Each protein can act as a substrate for polymerization or hydrolysis, or as a catalyst of these chemical reactions. When a protein is hydrolyzed to form two new proteins, or two proteins are joined into a single protein, the catalytic abilities of the product proteins are related to the catalytic abilities of the reactants. We will demonstrate that the catalytic capabilities of such a system can increase. Its evolutionary potential is dependent upon the competition between the formation of bond-forming and bond-cutting catalysts. The degree to which hydrolysis preferentially affects bonds in less efficient, and therefore less well

  15. An Urban Cellular Automata Model for Simulating Dynamic States on a Local Scale

    Directory of Open Access Journals (Sweden)

    Jenni Partanen

    2016-12-01

    Full Text Available In complex systems, flexibility and adaptability to changes are crucial to the systems’ dynamic stability and evolution. Such resilience requires that the system is able to respond to disturbances by self-organizing, which implies a certain level of entropy within the system. Dynamic states (static, cyclical/periodic, complex, and chaotic reflect this generative capacity, and correlate with the level of entropy. For planning complex cities, we need to develop methods to guide such autonomous progress in an optimal manner. A classical apparatus, cellular automaton (CA, provides such a tool. Applications of CA help us to study temporal dynamics in self-organizing urban systems. By exploring the dynamic states of the model’s dynamics resulting from different border conditions it is possible to discover favorable set(s of rules conductive to the self-organizing dynamics and enable the system’s recovery at the time of crises. Level of entropy is a relevant measurement for evaluation of these dynamic states. The 2-D urban cellular automaton model studied here is based on the microeconomic principle that similar urban activities are attracted to each other, especially in certain self-organizing areas, and that the local dynamics of these enclaves affect the dynamics of the urban region by channeling flows of information, goods and people. The results of the modeling experiment indicate that the border conditions have a major impact on the model’s dynamics generating various dynamic states of the system. Most importantly, it seemed that the model could simulate a favorable, complex dynamic state with medium entropy level which may refer to the continuous self-organization of the system. The model provides a tool for exploring and understanding the effects of boundary conditions in the planning process as various scenarios are tested: resulting dynamics of the system can be explored with such “planning rules” prior to decisions, helping to

  16. MUWS (Microbiology in Urban Water Systems – an interdisciplinary approach to study microbial communities in urban water systems

    Directory of Open Access Journals (Sweden)

    P. Deines

    2010-07-01

    Full Text Available Microbiology in Urban Water Systems (MUWS is an integrated project, which aims to characterize the microorganisms found in both potable water distribution systems and sewer networks. These large infrastructure systems have a major impact on our quality of life, and despite the importance of these systems as major components of the water cycle, little is known about their microbial ecology. Potable water distribution systems and sewer networks are both large, highly interconnected, dynamic, subject to time and varying inputs and demands, and difficult to control. Their performance also faces increasing loading due to increasing urbanization and longer-term environmental changes. Therefore, understanding the link between microbial ecology and any potential impacts on short or long-term engineering performance within urban water infrastructure systems is important. By combining the strengths and research expertise of civil-, biochemical engineers and molecular microbial ecologists, we ultimately aim to link microbial community abundance, diversity and function to physical and engineering variables so that novel insights into the performance and management of both water distribution systems and sewer networks can be explored. By presenting the details and principals behind the molecular microbiological techniques that we use, this paper demonstrates the potential of an integrated approach to better understand how urban water system function, and so meet future challenges.

  17. PM2006: a highly scalable urban planning management information system--Case study: Suzhou Urban Planning Bureau

    Science.gov (United States)

    Jing, Changfeng; Liang, Song; Ruan, Yong; Huang, Jie

    2008-10-01

    During the urbanization process, when facing complex requirements of city development, ever-growing urban data, rapid development of planning business and increasing planning complexity, a scalable, extensible urban planning management information system is needed urgently. PM2006 is such a system that can deal with these problems. In response to the status and problems in urban planning, the scalability and extensibility of PM2006 are introduced which can be seen as business-oriented workflow extensibility, scalability of DLL-based architecture, flexibility on platforms of GIS and database, scalability of data updating and maintenance and so on. It is verified that PM2006 system has good extensibility and scalability which can meet the requirements of all levels of administrative divisions and can adapt to ever-growing changes in urban planning business. At the end of this paper, the application of PM2006 in Urban Planning Bureau of Suzhou city is described.

  18. Valuing flexibilities in the design of urban water management systems.

    Science.gov (United States)

    Deng, Yinghan; Cardin, Michel-Alexandre; Babovic, Vladan; Santhanakrishnan, Deepak; Schmitter, Petra; Meshgi, Ali

    2013-12-15

    Climate change and rapid urbanization requires decision-makers to develop a long-term forward assessment on sustainable urban water management projects. This is further complicated by the difficulties of assessing sustainable designs and various design scenarios from an economic standpoint. A conventional valuation approach for urban water management projects, like Discounted Cash Flow (DCF) analysis, fails to incorporate uncertainties, such as amount of rainfall, unit cost of water, and other uncertainties associated with future changes in technological domains. Such approach also fails to include the value of flexibility, which enables managers to adapt and reconfigure systems over time as uncertainty unfolds. This work describes an integrated framework to value investments in urban water management systems under uncertainty. It also extends the conventional DCF analysis through explicit considerations of flexibility in systems design and management. The approach incorporates flexibility as intelligent decision-making mechanisms that enable systems to avoid future downside risks and increase opportunities for upside gains over a range of possible futures. A water catchment area in Singapore was chosen to assess the value of a flexible extension of standard drainage canals and a flexible deployment of a novel water catchment technology based on green roofs and porous pavements. Results show that integrating uncertainty and flexibility explicitly into the decision-making process can reduce initial capital expenditure, improve value for investment, and enable decision-makers to learn more about system requirements during the lifetime of the project. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. A Comprehensive System for Monitoring Urban Accessibility in Smart Cities.

    Science.gov (United States)

    Mora, Higinio; Gilart-Iglesias, Virgilio; Pérez-Del Hoyo, Raquel; Andújar-Montoya, María Dolores

    2017-08-09

    The present work discusses the possibilities offered by the evolution of Information and Communication Technologies with the aim of designing a system to dynamically obtain knowledge of accessibility issues in urban environments. This system is facilitated by technology to analyse the urban user experience and movement accessibility, which enabling accurate identification of urban barriers and monitoring its effectiveness over time. Therefore, the main purpose of the system is to meet the real needs and requirements of people with movement disabilities. The information obtained can be provided as a support service for decision-making to be used by city government, institutions, researchers, professionals and other individuals of society in general to improve the liveability and quality of the lives of citizens. The proposed system is a means of social awareness that makes the most vulnerable groups of citizens visible by involving them as active participants. To perform and implement the system, the latest communication and positioning technologies for smart sensing have been used, as well as the cloud computing paradigm. Finally, to validate the proposal, a case study has been presented using the university environment as a pre-deployment step in urban environments.

  20. Institutional Framework for Collaborative Urban Planning in Afghanistan in view of the Transferring Process of International Urban Planning Systems

    Directory of Open Access Journals (Sweden)

    Habib Ahmad Javid

    2015-09-01

    Full Text Available This article provides an overview of Afghanistan’s urban planning institutional change in certain historical periods, particular dilemmas within the current urban planning system and its gradual shift from totalitarian urban planning approaches practiced during 1960s - 1980s to a different form of planning being practiced by the current government. In addition, it will seek to analyze the ease and tension caused by the three recent phenomena that have emerged after the establishment of a new democratic government in Afghanistan since 2001, such as private sector-led urban development, international funding community’s and NGOs’ role in planning and the delegation of certain roles given to different tires of the government. Another purpose of this work is to analyze the collaboration among urban planning institutions, private sector, international funding community, NGOs and civil society within the current urban planning arena of Afghanistan and to identify the roles, responsibilities and functions of urban planning institutions in different levels of urban governance. Finally find out what possible and necessary institutional changes and framework are needed in order to foster grassroots based inter-institutional collaboration and partnership among various tires of government. The methodological approach to the research is based on qualitative data analysis. For the analysis purpose, government urban planning data and in-depth, semi-structured, face-to-face interviews with Afghanistan’s urban planning officials were thematically used, which provided in-depth information about involved actors in urban planning and their roles and relationships.

  1. Urban Systems during Disasters: Factors for Resilience

    Directory of Open Access Journals (Sweden)

    Deborah Wallace

    2008-06-01

    Full Text Available Urban neighborhoods form the basic functional unit of municipalities. Socioeconomically, they consist of social networks and interlocking layers of social networks. Old, stable neighborhoods are blessed with large social networks and dense interlocking layers. Both social control and social support depend on these complex structures of tight and loose ties. Public health and public order depend on these structures. They are the basis of resilience of both the neighborhood itself and of the municipality that is composed of neighborhoods. In New York City in the 1970s and later, domain shift occurred because of the disruption of the socioeconomic structure by the massive destruction of low-rental housing. A combined epidemic of building fires and landlord abandonment of buildings leveled a huge percentage of housing in poor neighborhoods and forced mass migration between neighborhoods. Social relationships that had existed between families and individuals for decades were destroyed. Community efficacy also greatly diminished. Drug use, violent crime, tuberculosis, and low-weight births were among the many public health and public order problems that soared in incidence consequent to the unraveling of the communities. These problems spilled out into the metropolitan region of dependent suburban counties. The ability of a municipality and its dependent suburban counties to weather a disaster such as an avian flu pandemic depends on the size of social networks in its neighborhoods and on the interconnection between the social networks. Diversity such as gained by social and economic integration influences the strength of the loose ties between social networks. Poor neighborhoods with extreme resilience conferred by a dense fabric of social networks must also maintain connections with mainstream political structure or they will fail to react to both good and bad impacts and communications.

  2. Urban Transportation Planning Short Course: Evaluation of Alternative Transportation Systems.

    Science.gov (United States)

    Federal Highway Administration (DOT), Washington, DC.

    This urban transportation pamphlet delves into the roles of policy groups and technical staffs in evaluating alternative transportation plans, evaluation criteria, systems to evaluate, and evaluation procedures. The introduction admits the importance of subjective, but informed, judgment as an effective tool in weighing alternative transportation…

  3. SUSTAIN:Urban Modeling Systems Integrating Optimization and Economics

    Science.gov (United States)

    The System for Urban Stormwater Treatment and Analysis INtegration (SUSTAIN) was developed by the U.S. Environmental Protection Agency to support practitioners in developing cost-effective management plans for municipal storm water programs and evaluating and selecting Best Manag...

  4. A Scanning scheimpflug lidar system developed for urban pollution monitoring

    Science.gov (United States)

    Yang, Yang; Guan, Peng; Mei, Liang

    2018-04-01

    A scanning Scheimpflug lidar system based on the Scheimpflug principle has been developed by employing a high power multimode 808 nm laser diode and a highly integrated CMOS sensor in Dalian University of Technology, Dalian, Northern China. Atmospheric scanning measurements in urban area were performed for the studies of particle emission sources.

  5. Landscapes of facilitation: how self-organized patchiness of aquatic macrophytes promotes diversity in streams.

    Science.gov (United States)

    Cornacchia, Loreta; van de Koppel, Johan; van der Wal, Daphne; Wharton, Geraldene; Puijalon, Sara; Bouma, Tjeerd J

    2018-04-01

    Spatial heterogeneity plays a crucial role in the coexistence of species. Despite recognition of the importance of self-organization in creating environmental heterogeneity in otherwise uniform landscapes, the effects of such self-organized pattern formation in promoting coexistence through facilitation are still unknown. In this study, we investigated the effects of pattern formation on species interactions and community spatial structure in ecosystems with limited underlying environmental heterogeneity, using self-organized patchiness of the aquatic macrophyte Callitriche platycarpa in streams as a model system. Our theoretical model predicted that pattern formation in aquatic vegetation - due to feedback interactions between plant growth, water flow and sedimentation processes - could promote species coexistence, by creating heterogeneous flow conditions inside and around the plant patches. The spatial plant patterns predicted by our model agreed with field observations at the reach scale in naturally vegetated rivers, where we found a significant spatial aggregation of two macrophyte species around C. platycarpa. Field transplantation experiments showed that C. platycarpa had a positive effect on the growth of both beneficiary species, and the intensity of this facilitative effect was correlated with the heterogeneous hydrodynamic conditions created within and around C. platycarpa patches. Our results emphasize the importance of self-organized patchiness in promoting species coexistence by creating a landscape of facilitation, where new niches and facilitative effects arise in different locations. Understanding the interplay between competition and facilitation is therefore essential for successful management of biodiversity in many ecosystems. © 2018 The Authors Ecology published by Wiley Periodicals, Inc. on behalf of Ecological Society of America.

  6. Environmental and natural resource implications of sustainable urban infrastructure systems

    Science.gov (United States)

    Bergesen, Joseph D.; Suh, Sangwon; Baynes, Timothy M.; Kaviti Musango, Josephine

    2017-12-01

    As cities grow, their environmental and natural resource footprints also tend to grow to keep up with the increasing demand on essential urban services such as passenger transportation, commercial space, and thermal comfort. The urban infrastructure systems, or socio-technical systems providing these services are the major conduits through which natural resources are consumed and environmental impacts are generated. This paper aims to gauge the potential reductions in environmental and resources footprints through urban transformation, including the deployment of resource-efficient socio-technical systems and strategic densification. Using hybrid life cycle assessment approach combined with scenarios, we analyzed the greenhouse gas (GHG) emissions, water use, metal consumption and land use of selected socio-technical systems in 84 cities from the present to 2050. The socio-technical systems analyzed are: (1) bus rapid transit with electric buses, (2) green commercial buildings, and (3) district energy. We developed a baseline model for each city considering gross domestic product, population density, and climate conditions. Then, we overlaid three scenarios on top of the baseline model: (1) decarbonization of electricity, (2) aggressive deployment of resource-efficient socio-technical systems, and (3) strategic urban densification scenarios to each city and quantified their potentials in reducing the environmental and resource impacts of cities by 2050. The results show that, under the baseline scenario, the environmental and natural resource footprints of all 84 cities combined would increase 58%-116% by 2050. The resource-efficient scenario along with strategic densification, however, has the potential to curve down GHG emissions to 17% below the 2010 level in 2050. Such transformation can also limit the increase in all resource footprints to less than 23% relative to 2010. This analysis suggests that resource-efficient urban infrastructure and decarbonization of

  7. Mimosa Origami: A nanostructure-enabled directional self-organization regime of materials

    Science.gov (United States)

    Wong, William S. Y.; Li, Minfei; Nisbet, David R.; Craig, Vincent S. J.; Wang, Zuankai; Tricoli, Antonio

    2016-01-01

    One of the innate fundamentals of living systems is their ability to respond toward distinct stimuli by various self-organization behaviors. Despite extensive progress, the engineering of spontaneous motion in man-made inorganic materials still lacks the directionality and scale observed in nature. We report the directional self-organization of soft materials into three-dimensional geometries by the rapid propagation of a folding stimulus along a predetermined path. We engineer a unique Janus bilayer architecture with superior chemical and mechanical properties that enables the efficient transformation of surface energy into directional kinetic and elastic energies. This Janus bilayer can respond to pinpoint water stimuli by a rapid, several-centimeters-long self-assembly that is reminiscent of the Mimosa pudica’s leaflet folding. The Janus bilayers also shuttle water at flow rates up to two orders of magnitude higher than traditional wicking-based devices, reaching velocities of 8 cm/s and flow rates of 4.7 μl/s. This self-organization regime enables the ease of fabricating curved, bent, and split flexible channels with lengths greater than 10 cm, demonstrating immense potential for microfluidics, biosensors, and water purification applications. PMID:28861471

  8. Self-organized lattice of ordered quantum dot molecules

    International Nuclear Information System (INIS)

    Lippen, T. von; Noetzel, R.; Hamhuis, G.J.; Wolter, J.H.

    2004-01-01

    Ordered groups of InAs quantum dots (QDs), lateral QD molecules, are created by self-organized anisotropic strain engineering of a (In,Ga)As/GaAs superlattice (SL) template on GaAs (311)B in molecular-beam epitaxy. During stacking, the SL template self-organizes into a two-dimensionally ordered strain modulated network on a mesoscopic length scale. InAs QDs preferentially grow on top of the nodes of the network due to local strain recognition. The QDs form a lattice of separated groups of closely spaced ordered QDs whose number can be controlled by the GaAs separation layer thickness on top of the SL template. The QD groups exhibit excellent optical properties up to room temperature

  9. SOUNET: Self-Organized Underwater Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Hee-won Kim

    2017-02-01

    Full Text Available In this paper, we propose an underwater wireless sensor network (UWSN named SOUNET where sensor nodes form and maintain a tree-topological network for data gathering in a self-organized manner. After network topology discovery via packet flooding, the sensor nodes consistently update their parent node to ensure the best connectivity by referring to the timevarying neighbor tables. Such a persistent and self-adaptive method leads to high network connectivity without any centralized control, even when sensor nodes are added or unexpectedly lost. Furthermore, malfunctions that frequently happen in self-organized networks such as node isolation and closed loop are resolved in a simple way. Simulation results show that SOUNET outperforms other conventional schemes in terms of network connectivity, packet delivery ratio (PDR, and energy consumption throughout the network. In addition, we performed an experiment at the Gyeongcheon Lake in Korea using commercial underwater modems to verify that SOUNET works well in a real environment.

  10. SOUNET: Self-Organized Underwater Wireless Sensor Network.

    Science.gov (United States)

    Kim, Hee-Won; Cho, Ho-Shin

    2017-02-02

    In this paper, we propose an underwater wireless sensor network (UWSN) named SOUNET where sensor nodes form and maintain a tree-topological network for data gathering in a self-organized manner. After network topology discovery via packet flooding, the sensor nodes consistently update their parent node to ensure the best connectivity by referring to the timevarying neighbor tables. Such a persistent and self-adaptive method leads to high network connectivity without any centralized control, even when sensor nodes are added or unexpectedly lost. Furthermore, malfunctions that frequently happen in self-organized networks such as node isolation and closed loop are resolved in a simple way. Simulation results show that SOUNET outperforms other conventional schemes in terms of network connectivity, packet delivery ratio (PDR), and energy consumption throughout the network. In addition, we performed an experiment at the Gyeongcheon Lake in Korea using commercial underwater modems to verify that SOUNET works well in a real environment.

  11. A self-organized criticality model for plasma transport

    International Nuclear Information System (INIS)

    Carreras, B.A.; Newman, D.; Lynch, V.E.

    1996-01-01

    Many models of natural phenomena manifest the basic hypothesis of self-organized criticality (SOC). The SOC concept brings together the self-similarity on space and time scales that is common to many of these phenomena. The application of the SOC modelling concept to the plasma dynamics near marginal stability opens new possibilities of understanding issues such as Bohm scaling, profile consistency, broad band fluctuation spectra with universal characteristics and fast time scales. A model realization of self-organized criticality for plasma transport in a magnetic confinement device is presented. The model is based on subcritical resistive pressure-gradient-driven turbulence. Three-dimensional nonlinear calculations based on this model show the existence of transport under subcritical conditions. This model that includes fluctuation dynamics leads to results very similar to the running sandpile paradigm

  12. Energy driven self-organization in nanoscale metallic liquid films.

    Science.gov (United States)

    Krishna, H; Shirato, N; Favazza, C; Kalyanaraman, R

    2009-10-01

    Nanometre thick metallic liquid films on inert substrates can spontaneously dewet and self-organize into complex nanomorphologies and nanostructures with well-defined length scales. Nanosecond pulses of an ultraviolet laser can capture the dewetting evolution and ensuing nanomorphologies, as well as introduce dramatic changes to dewetting length scales due to the nanoscopic nature of film heating. Here, we show theoretically that the self-organization principle, based on equating the rate of transfer of thermodynamic free energy to rate of loss in liquid flow, accurately describes the spontaneous dewetting. Experimental measurements of laser dewetting of Ag and Co liquid films on SiO(2) substrates confirm this principle. This energy transfer approach could be useful for analyzing the behavior of nanomaterials and chemical processes in which spontaneous changes are important.

  13. Self-organizing map models of language acquisition

    Science.gov (United States)

    Li, Ping; Zhao, Xiaowei

    2013-01-01

    Connectionist models have had a profound impact on theories of language. While most early models were inspired by the classic parallel distributed processing architecture, recent models of language have explored various other types of models, including self-organizing models for language acquisition. In this paper, we aim at providing a review of the latter type of models, and highlight a number of simulation experiments that we have conducted based on these models. We show that self-organizing connectionist models can provide significant insights into long-standing debates in both monolingual and bilingual language development. We suggest future directions in which these models can be extended, to better connect with behavioral and neural data, and to make clear predictions in testing relevant psycholinguistic theories. PMID:24312061

  14. 11th Workshop on Self-Organizing Maps

    CERN Document Server

    Mendenhall, Michael; O'Driscoll, Patrick

    2016-01-01

    This book contains the articles from the international conference 11th Workshop on Self-Organizing Maps 2016 (WSOM 2016), held at Rice University in Houston, Texas, 6-8 January 2016. WSOM is a biennial international conference series starting with WSOM'97 in Helsinki, Finland, under the guidance and direction of Professor Tuevo Kohonen (Emeritus Professor, Academy of Finland). WSOM brings together the state-of-the-art theory and applications in Competitive Learning Neural Networks: SOMs, LVQs and related paradigms of unsupervised and supervised vector quantization. The current proceedings present the expert body of knowledge of 93 authors from 15 countries in 31 peer reviewed contributions. It includes papers and abstracts from the WSOM 2016 invited speakers representing leading researchers in the theory and real-world applications of Self-Organizing Maps and Learning Vector Quantization: Professor Marie Cottrell (Universite Paris 1 Pantheon Sorbonne, France), Professor Pablo Estevez (University of Chile and ...

  15. Self-organized service negotiation for collaborative decision making.

    Science.gov (United States)

    Zhang, Bo; Huang, Zhenhua; Zheng, Ziming

    2014-01-01

    This paper proposes a self-organized service negotiation method for CDM in intelligent and automatic manners. It mainly includes three phases: semantic-based capacity evaluation for the CDM sponsor, trust computation of the CDM organization, and negotiation selection of the decision-making service provider (DMSP). In the first phase, the CDM sponsor produces the formal semantic description of the complex decision task for DMSP and computes the capacity evaluation values according to participator instructions from different DMSPs. In the second phase, a novel trust computation approach is presented to compute the subjective belief value, the objective reputation value, and the recommended trust value. And in the third phase, based on the capacity evaluation and trust computation, a negotiation mechanism is given to efficiently implement the service selection. The simulation experiment results show that our self-organized service negotiation method is feasible and effective for CDM.

  16. Energy sources, self-organization, and the origin of life.

    Science.gov (United States)

    Boiteau, Laurent; Pascal, Robert

    2011-02-01

    The emergence and early developments of life are considered from the point of view that contingent events that inevitably marked evolution were accompanied by deterministic driving forces governing the selection between different alternatives. Accordingly, potential energy sources are considered for their propensity to induce self-organization within the scope of the chemical approach to the origin of life. Requirements in terms of quality of energy locate thermal or photochemical activation in the atmosphere as highly likely processes for the formation of activated low-molecular weight organic compounds prone to induce biomolecular self-organization through their ability to deliver quanta of energy matching the needs of early biochemical pathways or the reproduction of self-replicating entities. These lines of reasoning suggest the existence of a direct connection between the free energy content of intermediates of early pathways and the quanta of energy delivered by available sources of energy.

  17. Self-Organized Criticality of Rainfall in Central China

    Directory of Open Access Journals (Sweden)

    Zhiliang Wang

    2012-01-01

    Full Text Available Rainfall is a complexity dynamics process. In this paper, our objective is to find the evidence of self-organized criticality (SOC for rain datasets in China by employing the theory and method of SOC. For this reason, we analyzed the long-term rain records of five meteorological stations in Henan, a central province of China. Three concepts, that is, rain duration, drought duration, accumulated rain amount, are proposed to characterize these rain events processes. We investigate their dynamics property by using scale invariant and found that the long-term rain processes in central China indeed exhibit the feature of self-organized criticality. The proposed theory and method may be suitable to analyze other datasets from different climate zones in China.

  18. Comparison of PV system design software packages for urban applications

    Energy Technology Data Exchange (ETDEWEB)

    Gharakhani Siraki, Arbi; Pillay, Pragasen

    2010-09-15

    A large number of software packages are available for solar resource evaluation and PV system design. However, few of them are suitable for urban applications. In this paper a comparison has been made between two specifically designed solar tools known as the Ecotect 2010 and the PVsyst 5.05. Conclusions have been made for proper use of these packages based on their specifications and privileges. Moreover, the calculations have been repeated with HOMER software package (which is a generic tool) for the same location. The results suggest that a generic solar software tool should not be used for an urban application.

  19. Socio-Environmental Resilience and Complex Urban Systems Modeling

    Science.gov (United States)

    Deal, Brian; Petri, Aaron; Pan, Haozhi; Goldenberg, Romain; Kalantari, Zahra; Cvetkovic, Vladimir

    2017-04-01

    The increasing pressure of climate change has inspired two normative agendas; socio-technical transitions and socio-ecological resilience, both sharing a complex-systems epistemology (Gillard et al. 2016). Socio-technical solutions include a continuous, massive data gathering exercise now underway in urban places under the guise of developing a 'smart'(er) city. This has led to the creation of data-rich environments where large data sets have become central to monitoring and forming a response to anomalies. Some have argued that these kinds of data sets can help in planning for resilient cities (Norberg and Cumming 2008; Batty 2013). In this paper, we focus on a more nuanced, ecologically based, socio-environmental perspective of resilience planning that is often given less consideration. Here, we broadly discuss (and model) the tightly linked, mutually influenced, social and biophysical subsystems that are critical for understanding urban resilience. We argue for the need to incorporate these sub system linkages into the resilience planning lexicon through the integration of systems models and planning support systems. We make our case by first providing a context for urban resilience from a socio-ecological and planning perspective. We highlight the data needs for this type of resilient planning and compare it to currently collected data streams in various smart city efforts. This helps to define an approach for operationalizing socio-environmental resilience planning using robust systems models and planning support systems. For this, we draw from our experiences in coupling a spatio-temporal land use model (the Landuse Evolution and impact Assessment Model (LEAM)) with water quality and quantity models in Stockholm Sweden. We describe the coupling of these systems models using a robust Planning Support System (PSS) structural framework. We use the coupled model simulations and PSS to analyze the connection between urban land use transformation (social) and water

  20. Expression cartography of human tissues using self organizing maps

    Directory of Open Access Journals (Sweden)

    Löffler Markus

    2011-07-01

    Full Text Available Abstract Background Parallel high-throughput microarray and sequencing experiments produce vast quantities of multidimensional data which must be arranged and analyzed in a concerted way. One approach to addressing this challenge is the machine learning technique known as self organizing maps (SOMs. SOMs enable a parallel sample- and gene-centered view of genomic data combined with strong visualization and second-level analysis capabilities. The paper aims at bridging the gap between the potency of SOM-machine learning to reduce dimension of high-dimensional data on one hand and practical applications with special emphasis on gene expression analysis on the other hand. Results The method was applied to generate a SOM characterizing the whole genome expression profiles of 67 healthy human tissues selected from ten tissue categories (adipose, endocrine, homeostasis, digestion, exocrine, epithelium, sexual reproduction, muscle, immune system and nervous tissues. SOM mapping reduces the dimension of expression data from ten of thousands of genes to a few thousand metagenes, each representing a minicluster of co-regulated single genes. Tissue-specific and common properties shared between groups of tissues emerge as a handful of localized spots in the tissue maps collecting groups of co-regulated and co-expressed metagenes. The functional context of the spots was discovered using overrepresentation analysis with respect to pre-defined gene sets of known functional impact. We found that tissue related spots typically contain enriched populations of genes related to specific molecular processes in the respective tissue. Analysis techniques normally used at the gene-level such as two-way hierarchical clustering are better represented and provide better signal-to-noise ratios if applied to the metagenes. Metagene-based clustering analyses aggregate the tissues broadly into three clusters containing nervous, immune system and the remaining tissues

  1. General fluid theories, variational principles and self-organization

    International Nuclear Information System (INIS)

    Mahajan, S.M.

    2002-01-01

    This paper reports two distinct but related advances: (1) The development and application of fluid theories that transcend conventional magnetohydrodynamics (MHD), in particular, theories that are valid in the long-mean-free-path limit and in which pressure anisotropy, heat flow, and arbitrarily strong sheared flows are treated consistently. (2) The discovery of new pressure-confining plasma configurations that are self-organized relaxed states. (author)

  2. Structures formation through self-organized accretion on cosmic strings

    International Nuclear Information System (INIS)

    Murdzek, R.

    2009-01-01

    In this paper, we shall show that the formation of structures through accretion by a cosmic string is driven by a natural feed-back mechanism: a part of the energy radiated by accretions creates a pressure on the accretion disk itself. This phenomenon leads to a nonlinear evolution of the accretion process. Thus, the formation of structures results as a consequence of a self-organized growth of the accreting central object.

  3. Self-organized vortex multiplets in swirling flow

    DEFF Research Database (Denmark)

    Okulov, Valery; Naumov, Igor; Sørensen, Jens Nørkær

    2008-01-01

    The possibility of double vortex multiplet formation at the center of an intensively swirling cocurrent flow generated in a cylindrical container by its rotating lid is reported for the first time. The boundary of the transition to unsteady flow regimes, which arise as a result of the equilibrium...... rotation of self-organized vortex multiplets (triplet, double triplet, double doublet, and quadruplet), has been experimentally determined for cylinders with the aspect (height to radius) ratios in a wider interval than that studied previously....

  4. Geographical information systems (GIS), a great tool for urban silviculture

    International Nuclear Information System (INIS)

    Otaya Burbano, Leodan Andres; Sanchez Zapata, Robinson de Jesus; Morales Soto, Leon; Botero Fernandez, Veronica

    2006-01-01

    As a pilot phase, to acquire experience, define methodologies and determine the advantages of Geographical Information Systems (GIS) for applying to urban silviculture and inventory, diagnosis, management plan and economic appraisal were made for the urban forest in the Magnolia neighborhood of the Envigado municipality, department of Antioquia, Colombia. for the management and analysis of the data collected in field, a database was designed using the software microsoft Access. The species inventoried were mapped digitally and the conditions there were analyzed using some tools and extensions of technological architecture ArcGIS 8.3 such as: characteristics, silviculture practices required, and environmental conflicts. It was determined that the GIS analysis of the urban forest conducted for a specific neighborhood can be a tool that permits environmental authorities and interested researchers to have agile and easy access to the information stored in it; it permits programming of required silviculture activities; it also permits having a general vision of the urban forest according to the infrastructure of the neighborhood, complemented by photographs of the area for improved illustration; it permits the inclusion or elimination of information in a rapid and simple manner, thus facilitating decision making with relation to management of the urban woodland and for comparison with other similar studies

  5. Environmental-benefit analysis of two urban waste collection systems.

    Science.gov (United States)

    Aranda Usón, Alfonso; Ferreira, Germán; Zambrana Vásquez, David; Zabalza Bribián, Ignacio; Llera Sastresa, Eva

    2013-10-01

    Sustainable transportation infrastructure and travel policies aim to optimise the use of transportation systems to achieve economic and related social and environmental goals. To this end, a novel methodology based on life cycle assessment (LCA) has been developed in this study, with the aim of quantifying, in terms of CO2 emissions equivalent, the impact associated with different alternatives of waste collection systems in different urban typologies. This new approach is focussed on saving energy and raw materials and reducing the environmental impact associated with the waste collection system in urban areas, as well as allowing the design and planning of the best available technologies and most environment-friendly management. The methodology considers a large variety of variables from the point of view of sustainable urban transport such as the location and size of the urban area, the amount of solid waste generated, the level of social awareness on waste separation procedures, the distance between houses and waste collection points and the distance from the latter to the possible recovery plants and/or landfills, taking into account the material and energy recovery ratio within an integrated waste management system. As a case study, two different waste collection systems have been evaluated with this methodology in the ecocity Valdespartera located in Zaragoza, Spain, consisting of approximately 10,000 homes: (i) a system based on traditional truck transportation and manual collection, and (ii) a stationary vacuum waste collection system. Results show that, when operating at loads close to 100%, the stationary collection system has the best environmental performance in comparison with the conventional system. In contrast, when operating at load factors around 13% the environmental benefits in terms of net CO2-eq. emissions for the stationary collection system are around 60% lower in comparison with the conventional one. Copyright © 2013 Elsevier B.V. All

  6. Institutional Framework for Collaborative Urban Planning in Afghanistan in view of the Transferring Process of International Urban Planning Systems

    OpenAIRE

    Habib Ahmad Javid; Tetsuo Kidokoro

    2015-01-01

    This article provides an overview of Afghanistan’s urban planning institutional change in certain historical periods, particular dilemmas within the current urban planning system and its gradual shift from totalitarian urban planning approaches practiced during 1960s - 1980s to a different form of planning being practiced by the current government. In addition, it will seek to analyze the ease and tension caused by the three recent phenomena that have emerged after the establishment of a new ...

  7. Conceptual study of superconducting urban area power systems

    International Nuclear Information System (INIS)

    Noe, Mathias; Gold-acker, Wilfried; Bach, Robert; Prusseit, Werner; Willen, Dag; Poelchau, Juri; Linke, Christian

    2010-01-01

    Efficient transmission, distribution and usage of electricity are fundamental requirements for providing citizens, societies and economies with essential energy resources. It will be a major future challenge to integrate more sustainable generation resources, to meet growing electricity demand and to renew electricity networks. Research and development on superconducting equipment and components have an important role to play in addressing these challenges. Up to now, most studies on superconducting applications in power systems have been concentrated on the application of specific devices like for example cables and current limiters. In contrast to this, the main focus of our study is to show the consequence of a large scale integration of superconducting power equipment in distribution level urban power systems. Specific objectives are to summarize the state-of-the-art of superconducting power equipment including cooling systems and to compare the superconducting power system with respect to energy and economic efficiency with conventional solutions. Several scenarios were considered starting from the replacement of an existing distribution level sub-grid up to a full superconducting urban area distribution level power system. One major result is that a full superconducting urban area distribution level power system could be cost competitive with existing solutions in the future. In addition to that, superconducting power systems offer higher energy efficiency as well as a number of technical advantages like lower voltage drops and improved stability.

  8. Energy saving and recovery measures in integrated urban water systems

    Science.gov (United States)

    Freni, Gabriele; Sambito, Mariacrocetta

    2017-11-01

    The present paper describes different energy production, recovery and saving measures which can be applied in an integrated urban water system. Production measures are often based on the installation of photovoltaic systems; the recovery measures are commonly based on hydraulic turbines, exploiting the available pressure potential to produce energy; saving measures are based on substitution of old pumps with higher efficiency ones. The possibility of substituting some of the pipes of the water supply system can be also considered in a recovery scenario in order to reduce leakages and recovery part of the energy needed for water transport and treatment. The reduction of water losses can be obtained through the Active Leakage Control (ALC) strategies resulting in a reduction in energy consumption and in environmental impact. Measures were applied to a real case study to tested it the efficiency, i.e., the integrated urban water system of the Palermo metropolitan area in Sicily (Italy).

  9. Urban Security Initiative: Earthquake impacts on the urban ``system of systems``

    Energy Technology Data Exchange (ETDEWEB)

    Maheshwari, S.; Jones, E.; Rasmussen, S.

    1999-06-01

    This paper is a discussion of how to address the problems of disasters in a large city, a project titled Urban Security Initiative undertaken by the Los Alamos National Laboratory. The paper first discusses the need to address the problems of disasters in large cities and ten provides a framework that is suitable to address this problem. The paper then provides an overview of the module of the project that deals with assessment of earthquake damage on urban infrastructure in large cities and an internet-based approach for consensus building leading to better coordination in the post-disaster period. Finally, the paper discusses the future direction of the project.

  10. A Data-Driven, Integrated Flare Model Based on Self-Organized Criticality

    Science.gov (United States)

    Dimitropoulou, M.; Isliker, H.; Vlahos, L.; Georgoulis, M.

    2013-09-01

    We interpret solar flares as events originating in solar active regions having reached the self-organized critical state, by alternatively using two versions of an "integrated flare model" - one static and one dynamic. In both versions the initial conditions are derived from observations aiming to investigate whether well-known scaling laws observed in the distribution functions of characteristic flare parameters are reproduced after the self-organized critical state has been reached. In the static model, we first apply a nonlinear force-free extrapolation that reconstructs the three-dimensional magnetic fields from two-dimensional vector magnetograms. We then locate magnetic discontinuities exceeding a threshold in the Laplacian of the magnetic field. These discontinuities are relaxed in local diffusion events, implemented in the form of cellular-automaton evolution rules. Subsequent loading and relaxation steps lead the system to self-organized criticality, after which the statistical properties of the simulated events are examined. In the dynamic version we deploy an enhanced driving mechanism, which utilizes the observed evolution of active regions, making use of sequential vector magnetograms. We first apply the static cellular automaton model to consecutive solar vector magnetograms until the self-organized critical state is reached. We then evolve the magnetic field inbetween these processed snapshots through spline interpolation, acting as a natural driver in the dynamic model. The identification of magnetically unstable sites as well as their relaxation follow the same rules as in the static model after each interpolation step. Subsequent interpolation/driving and relaxation steps cover all transitions until the end of the sequence. Physical requirements, such as the divergence-free condition for the magnetic field vector, are approximately satisfied in both versions of the model. We obtain robust power laws in the distribution functions of the modelled

  11. Performance indicators for the efficiency analysis of urban drainage systems.

    Science.gov (United States)

    Artina, S; Becciu, G; Maglionico, M; Paoletti, A; Sanfilippo, U

    2005-01-01

    Performance indicators implemented in a decision support system (DSS) for the technical, managerial and economic evaluation of urban drainage systems (UDS), called MOMA FD, are presented. Several kinds of information are collected and processed by MOMA FD to evaluate both present situation and future scenarios of development and enhancement. Particular interest is focused on the evaluation of the environmental impact, which is considered a very relevant factor in the decision making process to identify the priorities for UDS improvements.

  12. Supramolecular chemistry: from molecular information towards self-organization and complex matter

    International Nuclear Information System (INIS)

    Lehn, Jean-Marie

    2004-01-01

    Molecular chemistry has developed a wide range of very powerful procedures for constructing ever more sophisticated molecules from atoms linked by covalent bonds. Beyond molecular chemistry lies supramolecular chemistry, which aims at developing highly complex chemical systems from components interacting via non-covalent intermolecular forces. By the appropriate manipulation of these interactions, supramolecular chemistry became progressively the chemistry of molecular information, involving the storage of information at the molecular level, in the structural features, and its retrieval, transfer, and processing at the supramolecular level, through molecular recognition processes operating via specific interactional algorithms. This has paved the way towards apprehending chemistry also as an information science. Numerous receptors capable of recognizing, i.e. selectively binding, specific substrates have been developed, based on the molecular information stored in the interacting species. Suitably functionalized receptors may perform supramolecular catalysis and selective transport processes. In combination with polymolecular organization, recognition opens ways towards the design of molecular and supramolecular devices based on functional (photoactive, electroactive, ionoactive, etc) components. A step beyond preorganization consists in the design of systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined supramolecular architectures by self-assembly from their components. Self-organization processes, directed by the molecular information stored in the components and read out at the supramolecular level through specific interactions, represent the operation of programmed chemical systems. They have been implemented for the generation of a variety of discrete functional architectures of either organic or inorganic nature. Self-organization processes also give access to advanced supramolecular materials, such as

  13. Adaptive traffic control systems for urban networks

    Directory of Open Access Journals (Sweden)

    Radivojević Danilo

    2017-01-01

    Full Text Available Adaptive traffic control systems represent complex, but powerful tool for improvement of traffic flow conditions in locations or zones where applied. Many traffic agencies, especially those that have a large number of signalized intersections with high variability of the traffic demand, choose to apply some of the adaptive traffic control systems. However, those systems are manufactured and offered by multiple vendors (companies that are competing for the market share. Due to that fact, besides the information available from the vendors themselves, or the information from different studies conducted on different continents, very limited amount of information is available about the details how those systems are operating. The reason for that is the protecting of the intellectual property from plagiarism. The primary goal of this paper is to make a brief analysis of the functionalities, characteristics, abilities and results of the most recognized, but also less known adaptive traffic control systems to the professional public and other persons with interest in this subject.

  14. Modeling carbon emissions from urban traffic system using mobile monitoring.

    Science.gov (United States)

    Sun, Daniel Jian; Zhang, Ying; Xue, Rui; Zhang, Yi

    2017-12-01

    Comprehensive analyses of urban traffic carbon emissions are critical in achieving low-carbon transportation. This paper started from the architecture design of a carbon emission mobile monitoring system using multiple sets of equipment and collected the corresponding data about traffic flow, meteorological conditions, vehicular carbon emissions and driving characteristics on typical roads in Shanghai and Wuxi, Jiangsu province. Based on these data, the emission model MOVES was calibrated and used with various sensitivity and correlation evaluation indices to analyze the traffic carbon emissions at microscopic, mesoscopic and macroscopic levels, respectively. The major factors that influence urban traffic carbon emissions were investigated, so that emission factors of CO, CO 2 and HC were calculated by taking representative passenger cars as a case study. As a result, the urban traffic carbon emissions were assessed quantitatively, and the total amounts of CO, CO 2 and HC emission from passenger cars in Shanghai were estimated as 76.95kt, 8271.91kt, and 2.13kt, respectively. Arterial roads were found as the primary line source, accounting for 50.49% carbon emissions. In additional to the overall major factors identified, the mobile monitoring system and carbon emission quantification method proposed in this study are of rather guiding significance for the further urban low-carbon transportation development. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Stereo-based Collision Avoidance System for Urban Traffic

    Science.gov (United States)

    Moriya, Takashi; Ishikawa, Naoto; Sasaki, Kazuyuki; Nakajima, Masato

    2002-11-01

    Numerous car accidents occur on urban road. However, researches done so far on driving assistance are subjecting highways whose environment is relatively simple and easy to handle, and new approach for urban settings is required. Our purpose is to extend its support to the following conditions in city traffic: the presence of obstacles such as pedestrians and telephone poles; the lane mark is not always drawn on a road; drivers may lack the sense of awareness of the lane mark. We propose a collision avoidance system, which can be applied to both highways and urban traffic environment. In our system, stereo cameras are set in front of a vehicle and the captured images are processed through a computer. We create a Projected Disparity Map (PDM) from stereo image pair, which is a disparity histogram taken along ordinate direction of obtained disparity image. When there is an obstacle in front, we can detect it by finding a peak appeared in the PDM. With a speed meter and a steering sensor, the stop distance and the radius of curvature of the self-vehicle are calculated, in order to set the observation-required area, which does not depend on lane marks, within a PDM. A danger level will be computed from the distance and the relative speed to the closest approaching object detected within the observation-required area. The method has been tested in urban traffic scenes and has shown to be effective for judging dangerous situation, and gives proper alarm to a driver.

  16. Integrated Quality Management System in Public Urban Traffic

    Directory of Open Access Journals (Sweden)

    Husein Pašagić

    2005-09-01

    Full Text Available Public urban traffic (PUT requirements are based on thespecific characteristics that dictate the requirements themselves.The problems faced by all the big cities regarding public urbantransport are very similar, and they range from unacceptabilityof the very organisational structure of the system facing the populationgrowth, limitations and congestions of the traffic routesloaded by an increasing number of automobiles, to the chroniclack of economic funds for the investments that would createthe necessary conditions for positive shifts. In PUT there aremany random parameters whose statistical laws are not easy todetermine and it is often the topic of research of various profilesof scientists. There is always the satisfaction, that is, the lack ofsatisfaction by the final user of the public urban transport andall the other involved groups. The result is that the potential usersof public urban transport give up and try to find other solutionsfor their transport needs, turning in principle to individualtraffic. Consequently, the number of passenger cars on the trafficroutes increases along with all the resulting negative effects.The complex systems of public urban transport facing the increasingrequirements to improve efficiency have to be subjectedto certain changes in order to achieve physical sustainability oftraffic at all, and to satisfy the environmental requirements thatoccur as counterbalance to the pollution of the urban area.With the aim of achieving optimal conditions for the qualityof service, and by introducing acceptable traffic solutionscombined with the integrated quality management systembased on the standards ISO 9001 and ISO 14000 high-qualityshifts are made possible. The integration of these standards resultsin the rational combining of the quality management systeminto a single efficient system, reflected in achieving high-quality traffic and transport service, improved informationflow, unique documentation, positive

  17. Toward a Shared Urban Transport System Ensuring Passengers & Goods Cohabitation

    Directory of Open Access Journals (Sweden)

    Anna Trentini

    2010-07-01

    Full Text Available The paper presents radical new urban transportation system concepts, potentially allowing changing the economic and environmental costs of passenger and freight transportation. The driver focuses on the concept of sharing, which means to make a joint use of transport resources, between passengers and goods flows. From a field observation of several existing solutions, an inductive reasoning enables us to move from a set of specific facts to establish an archetype for a radical new urban transportation system. Once the archetype defined, it is translated in real life through the example of the On Route proposal for London. The research frame of this paper is the ANR C-Goods (City Goods Operation Optimization using Decision support System project. Started in February 2009 the project involves four partners , and will end on 2011.

  18. A Two-Stage Queue Model to Optimize Layout of Urban Drainage System considering Extreme Rainstorms

    OpenAIRE

    He, Xinhua; Hu, Wenfa

    2017-01-01

    Extreme rainstorm is a main factor to cause urban floods when urban drainage system cannot discharge stormwater successfully. This paper investigates distribution feature of rainstorms and draining process of urban drainage systems and uses a two-stage single-counter queue method M/M/1→M/D/1 to model urban drainage system. The model emphasizes randomness of extreme rainstorms, fuzziness of draining process, and construction and operation cost of drainage system. Its two objectives are total c...

  19. A stochastic approach for automatic generation of urban drainage systems.

    Science.gov (United States)

    Möderl, M; Butler, D; Rauch, W

    2009-01-01

    Typically, performance evaluation of new developed methodologies is based on one or more case studies. The investigation of multiple real world case studies is tedious and time consuming. Moreover extrapolating conclusions from individual investigations to a general basis is arguable and sometimes even wrong. In this article a stochastic approach is presented to evaluate new developed methodologies on a broader basis. For the approach the Matlab-tool "Case Study Generator" is developed which generates a variety of different virtual urban drainage systems automatically using boundary conditions e.g. length of urban drainage system, slope of catchment surface, etc. as input. The layout of the sewer system is based on an adapted Galton-Watson branching process. The sub catchments are allocated considering a digital terrain model. Sewer system components are designed according to standard values. In total, 10,000 different virtual case studies of urban drainage system are generated and simulated. Consequently, simulation results are evaluated using a performance indicator for surface flooding. Comparison between results of the virtual and two real world case studies indicates the promise of the method. The novelty of the approach is that it is possible to get more general conclusions in contrast to traditional evaluations with few case studies.

  20. The implementation of biofiltration systems, rainwater tanks and urban irrigation in a single-layer urban canopy model

    Science.gov (United States)

    Demuzere, Matthias; Coutts, Andrew; Goehler, Maren; Broadbent, Ashley; Wouters, Hendrik; van Lipzig, Nicole; Gebert, Luke

    2015-04-01

    Urban vegetation is generally considered as a key tool to modify the urban energy balance through enhanced evapotranspiration (ET). Given that vegetation is most effective when it is healthy, stormwater harvesting and retention strategies (such as water sensitive urban design) could be used to support vegetation and promote ET. This study presents the implementation of a vegetated lined bio-filtration system (BFS) combined with a rainwater tank (RWT) and urban irrigation system in the single-layer urban canopy model Community Land Model-Urban. Runoff from roof and impervious road surface fractions is harvested and used to support an adequate soil moisture level for vegetation in the BFS. In a first stage, modelled soil moisture dynamics are evaluated and found reliable compared to observed soil moisture levels from biofiltration pits in Smith Street, Melbourne (Australia). Secondly, the impact of BFS, RWT and urban irrigation on ET is illustrated for a two-month period in 2012 using varying characteristics for all components. Results indicate that (i) a large amount of stormwater is potentially available for indoor and outdoor water demands, including irrigation of urban vegetation, (ii) ET from the BFS is an order of magnitude larger compared to the contributions from the impervious surfaces, even though the former only covers 10% of the surface fraction and (iii) attention should be paid to the cover fraction and soil texture of the BFS, size of the RWT and the surface fractions contributing to the collection of water in the RWT. Overall, this study reveals that this model development can effectuate future research with state-of-the-art urban climate models to further explore the benefits of vegetated biofiltration systems as a water sensitive urban design tool optimised with an urban irrigation system to maintain healthy vegetation.

  1. Innovative economic structures – support for development of urban systems

    Directory of Open Access Journals (Sweden)

    Florin Marian Buhociu

    2013-12-01

    Full Text Available Training and development of urban systems (US is a main direction of territorial and regional development which requires multiple studies, including those of economic background. They should aim to highlight, on the one hand, the economic potential of geographical areas making up the urban system and secondly to assess development trends you need to focus their own resources and those that are to be attracted to getting a economic trend upward in that area. It is therefore very important a zonal configuration of the urban system by following the joint capitalization of existing human and material resources, including by building synergy effect to be achieved following the joint evolution of settlements in the US. Along with the development of US is required, from the economical point of view, to implement new forms of economic structures to directly potentate the development of the area through constant cooperation, innovation and transfer of know-how. Romania currently has seven major urban centers that were selected and were assigned the role of growth poles. There were also 13 designated urban growth poles, including Galati and Braila. Urban agglomeration formed by the two municipalities, located at a distance from each other of about 25 km, is the second largest in the country after Bucharest. There is currently underway specialized documentation to achieve an optimal configuration for US Galati-Braila. From the economic point of view in the respective area can be implemented new development structures of cluster (Porter, M.E.,2000 type aimed at achieving the competitiveness poles and which will constitute the true engine of economic development. These two new structures of economic development are characterized by the fact that they allow and provide the necessary conditions to attract the systems and modern technologies to build local innovation systems that can be integrated into similar systems at regional and even national level. It is

  2. Study on the complex network characteristics of urban road system based on GIS

    Science.gov (United States)

    Gao, Zhonghua; Chen, Zhenjie; Liu, Yongxue; Huang, Kang

    2007-06-01

    Urban road system is the basic bone of urban transportation and one of the most important factors that influent and controls the urban configuration. In this paper, an approach of modeling, analyzing and optimizing urban road system is described based on complex network theory and GIS technology. The urban road system is studied on three focuses: building the urban road network, modeling the computational procedures based on urban road networks and analyzing the urban road system of Changzhou City as the study case. The conclusion is that the urban road network is a scale-free network with small-world characteristic, and there is still space for development of the whole network as a small-world network, also the key road crosses should be kept expedite.

  3. Chaos-driven decay of nuclear giant resonances: Quantum route to self-organization

    International Nuclear Information System (INIS)

    Drozdz, S.; Nishizaki, S.; Wambach, J.

    1994-01-01

    The influence of background states with increasing level of complexity on the strength distribution of the isoscalar and isovector giant quadrupole resonance in 40 Ca is studied. It is found that the background characteristics, typical for chaotic systems, strongly affect the fluctuation properties of the strength distribution. In particular, the small components of the wave function obey a scaling law analogous to self-organized systems at the critical state. This appears to be consistent with the Porter-Thomas distribution of the transition strength

  4. URBAN SELF-ORGANISATION IN DEPRIVED NEIGHBORHOODS: POSSIBILITIES AND LIMITS OF AUTONOMOUS COLLECTIVE ARTICULATION IN SALVADOR DA BAHIA

    Directory of Open Access Journals (Sweden)

    Katja Hölldampf

    2013-07-01

    Full Text Available From a comparative point of view, the given article is concerned with the possibilities and restrictions of urban self-organization within city’s neighbourhoods. Drawing upon a qualitative comparison between the case studies Alto de Ondina and Alto da Sereia – two disadvantaged urban neighbourhoods in the southern city centre of Salvador da Bahia (Brazil – and considering the conditional framework of daily life there, the idiographic context conditions that foster and alternatively impede self-organization are to be developed on data drawn from empirical surveys. Here, the data-led interpretations reach beyond the local and regional context and offer fundamental insights into auto-centered and autonomous acts of articulation. In Brazil, participative planning processes have been the common sense for urban governance. However, participative strategies tend to stand under the sign of codetermination, whereas the principles of self-determination and auto-centered articulation of collective interests are immantently present during processes of civic self-organization. Due to the fact that self-organized communities do not fall within a defined institutional framework or existing system, they are capable to articulate their needs and interests collectively. The underlying concept of “Agora Governance” in accordance with Korff & Rothfuss (2009 offers the possibility to stimulate urban management processes in a sustainable way, bringing together the civic perspective of the “human city” and the expert perspective of the “infrastructural city” into a consensual but often highly disputed negotiation process.

  5. Understanding Resilient Urban Futures: A Systemic Modelling Approach

    Directory of Open Access Journals (Sweden)

    Ralph Chapman

    2013-07-01

    Full Text Available The resilience of cities in response to natural disasters and long-term climate change has emerged as a focus of academic and policy attention. In particular, how to understand the interconnectedness of urban and natural systems is a key issue. This paper introduces an urban model that can be used to evaluate city resilience outcomes under different policy scenarios. The model is the Wellington Integrated Land Use-Transport-Environment Model (WILUTE. It considers the city (i.e., Wellington as a complex system characterized by interactions between a variety of internal urban processes (social, economic and physical and the natural environment. It is focused on exploring the dynamic relations between human activities (the geographic distribution of housing and employment, infrastructure layout, traffic flows and energy consumption, environmental effects (carbon emissions, influences on local natural and ecological systems and potential natural disasters (e.g., inundation due to sea level rise and storm events faced under different policy scenarios. The model gives insights that are potentially useful for policy to enhance the city’s resilience, by modelling outcomes, such as the potential for reduction in transportation energy use, and changes in the vulnerability of the city’s housing stock and transport system to sea level rise.

  6. Self-Organization in Integrated Conservation and Development Initiatives

    Directory of Open Access Journals (Sweden)

    Cristiana Simão Seixas

    2007-11-01

    Full Text Available This paper uses a cooking metaphor to explore key elements (i.e., ingredients for a great meal that contribute to self-organization processes in the context of successful community-based conservation (CBC or integrated conservation and development projects (ICDP. We pose two major questions: (1 What are the key factors that drive peoples' and/or organizations' willingness to take responsibilities and to act? (2 What contributes to community self-organization? In other words, how conservation-development projects originate, evolve, survive or disappear? In order to address these questions we examine trigger events and catalytic elements in several cases among the Equator Prize finalists and short-listed nominees, from both the 2002 and 2004 awards. The Prize recognizes efforts in integrating biodiversity conservation and poverty reduction. We use secondary data in our analysis, including data from several technical reports and scientific papers written about the Equator Prize finalists and short-listed nominees. We observed common ingredients in most projects including: (1 involvement and commitment of key players (including communities, (2 funding, (3 strong leadership, (4 capacity building, (5 partnership with supportive organizations and government, and (6 economic incentives (including alternative livelihood options. We also observed that CBC and ICDP initiatives opportunistically evolve in a multi-level world, in which local communities establish linkages with people and organizations at different political levels, across different geographical scales and for different purposes. We conclude that there is no right 'recipe' to promote community self-organization but often a mix of some of these six ingredients need to come together for 'success' and that one or two ingredients are not sufficient to ensure success. Also the existence of these six ingredients does not guarantee a great meal - the 'chef's' creativity also is critical. That is

  7. Monitoring of health and demographic outcomes in poor urban settlements: evidence from the Nairobi Urban Health and Demographic Surveillance System.

    Science.gov (United States)

    Emina, Jacques; Beguy, Donatien; Zulu, Eliya M; Ezeh, Alex C; Muindi, Kanyiva; Elung'ata, Patricia; Otsola, John K; Yé, Yazoumé

    2011-06-01

    The Nairobi Urban Health and Demographic Surveillance System (NUHDSS) was set up in Korogocho and Viwandani slum settlements to provide a platform for investigating linkages between urban poverty, health, and demographic and other socioeconomic outcomes, and to facilitate the evaluation of interventions to improve the wellbeing of the urban poor. Data from the NUHDSS confirm the high level of population mobility in slum settlements, and also demonstrate that slum settlements are long-term homes for many people. Research and intervention programs should take account of the duality of slum residency. Consistent with the trends observed countrywide, the data show substantial improvements in measures of child mortality, while there has been limited decline in fertility in slum settlements. The NUHDSS experience has shown that it is feasible to set up and implement long-term health and demographic surveillance system in urban slum settlements and to generate vital data for guiding policy and actions aimed at improving the wellbeing of the urban poor.

  8. Self-organized template formation for quantum dot ordering

    International Nuclear Information System (INIS)

    Noetzel, Richard; Mano, Takaaki; Wolter, Joachim H.

    2004-01-01

    Ordered arrays of quantum dots (QDs) are created by self-organized anisotropic strain engineering of (In,Ga)As/GaAs quantum wire (QWR) superlattice (SL) templates on exactly oriented GaAs (100) substrates by molecular beam epitaxy (MBE). The well-defined one-dimensional arrays of (In,Ga)As QDs formed on top of these templates due to local strain recognition are of excellent structural and optical quality up to room temperature. The QD arrays thus allow for fundamental studies and device operation principles based on single- and multiple carrier- and photon-, and coherent quantum interference effects

  9. Self-organized Criticality Model for Ocean Internal Waves

    International Nuclear Information System (INIS)

    Wang Gang; Hou Yijun; Lin Min; Qiao Fangli

    2009-01-01

    In this paper, we present a simple spring-block model for ocean internal waves based on the self-organized criticality (SOC). The oscillations of the water blocks in the model display power-law behavior with an exponent of -2 in the frequency domain, which is similar to the current and sea water temperature spectra in the actual ocean and the universal Garrett and Munk deep ocean internal wave model [Geophysical Fluid Dynamics 2 (1972) 225; J. Geophys. Res. 80 (1975) 291]. The influence of the ratio of the driving force to the spring coefficient to SOC behaviors in the model is also discussed. (general)

  10. Theoretical and applied aspects of the self-organizing maps

    OpenAIRE

    Cottrell , Marie; Olteanu , Madalina; Rossi , Fabrice; Villa-Vialaneix , Nathalie

    2016-01-01

    International audience; The Self-Organizing Map (SOM) is widely used, easy to implement , has nice properties for data mining by providing both clustering and visual representation. It acts as an extension of the k-means algorithm that preserves as much as possible the topological structure of the data. However, since its conception, the mathematical study of the SOM remains difficult and has be done only in very special cases. In WSOM 2005, Jean-Claude Fort presented the state of the art, th...

  11. Self-Organized Criticality and Mass Extinction in Evolutionary Algorithms

    DEFF Research Database (Denmark)

    Krink, Thiemo; Thomsen, Rene

    2001-01-01

    The gaps in the fossil record gave rise to the hypothesis that evolution proceeded in long periods of stasis, which alternated with occasional, rapid changes that yielded evolutionary progress. One mechanism that could cause these punctuated bursts is the re-colonbation of changing and deserted...... at a critical state between chaos and order, known as self-organized criticality (SOC). Based on this background, we used SOC to control the size of spatial extinction zones in a diffusion model. The SOC selection process was easy to implement and implied only negligible computational costs. Our results show...

  12. Simple lecture demonstrations of instability and self-organization

    International Nuclear Information System (INIS)

    Mayer, V V; Varaksina, E I; Saranin, V A

    2014-01-01

    A dielectric liquid layer with an electric field created inside it is proposed as a means for demonstrating the phenomenon of self-organization. The field is produced by the distributed charge transferred by a corona discharge from the tip to the liquid surface. The theory of the phenomenon is presented. An analogy with the Rayleigh – Taylor instability is drawn and a comparison with the Benard instability is given. The practicality of the method for both natural sciences and the humanities is discussed. (methodological notes)

  13. Environmental-benefit analysis of two urban waste collection systems

    International Nuclear Information System (INIS)

    Aranda Usón, Alfonso; Ferreira, Germán; Zambrana Vásquez, David; Zabalza Bribián, Ignacio; Llera Sastresa, Eva

    2013-01-01

    Sustainable transportation infrastructure and travel policies aim to optimise the use of transportation systems to achieve economic and related social and environmental goals. To this end, a novel methodology based on life cycle assessment (LCA) has been developed in this study, with the aim of quantifying, in terms of CO 2 emissions equivalent, the impact associated with different alternatives of waste collection systems in different urban typologies. This new approach is focussed on saving energy and raw materials and reducing the environmental impact associated with the waste collection system in urban areas, as well as allowing the design and planning of the best available technologies and most environment-friendly management. The methodology considers a large variety of variables from the point of view of sustainable urban transport such as the location and size of the urban area, the amount of solid waste generated, the level of social awareness on waste separation procedures, the distance between houses and waste collection points and the distance from the latter to the possible recovery plants and/or landfills, taking into account the material and energy recovery ratio within an integrated waste management system. As a case study, two different waste collection systems have been evaluated with this methodology in the ecocity Valdespartera located in Zaragoza, Spain, consisting of approximately 10,000 homes: (i) a system based on traditional truck transportation and manual collection, and (ii) a stationary vacuum waste collection system. Results show that, when operating at loads close to 100%, the stationary collection system has the best environmental performance in comparison with the conventional system. In contrast, when operating at load factors around 13% the environmental benefits in terms of net CO 2 -eq. emissions for the stationary collection system are around 60% lower in comparison with the conventional one. - Highlights: • A comprehensive

  14. Environmental-benefit analysis of two urban waste collection systems

    Energy Technology Data Exchange (ETDEWEB)

    Aranda Usón, Alfonso, E-mail: alaranda@unizar.es; Ferreira, Germán; Zambrana Vásquez, David; Zabalza Bribián, Ignacio; Llera Sastresa, Eva

    2013-10-01

    Sustainable transportation infrastructure and travel policies aim to optimise the use of transportation systems to achieve economic and related social and environmental goals. To this end, a novel methodology based on life cycle assessment (LCA) has been developed in this study, with the aim of quantifying, in terms of CO{sub 2} emissions equivalent, the impact associated with different alternatives of waste collection systems in different urban typologies. This new approach is focussed on saving energy and raw materials and reducing the environmental impact associated with the waste collection system in urban areas, as well as allowing the design and planning of the best available technologies and most environment-friendly management. The methodology considers a large variety of variables from the point of view of sustainable urban transport such as the location and size of the urban area, the amount of solid waste generated, the level of social awareness on waste separation procedures, the distance between houses and waste collection points and the distance from the latter to the possible recovery plants and/or landfills, taking into account the material and energy recovery ratio within an integrated waste management system. As a case study, two different waste collection systems have been evaluated with this methodology in the ecocity Valdespartera located in Zaragoza, Spain, consisting of approximately 10,000 homes: (i) a system based on traditional truck transportation and manual collection, and (ii) a stationary vacuum waste collection system. Results show that, when operating at loads close to 100%, the stationary collection system has the best environmental performance in comparison with the conventional system. In contrast, when operating at load factors around 13% the environmental benefits in terms of net CO{sub 2}-eq. emissions for the stationary collection system are around 60% lower in comparison with the conventional one. - Highlights: • A

  15. Toward a shared urban transport system passengers & Goods Cohabitation

    Directory of Open Access Journals (Sweden)

    Anna Trentini

    2011-10-01

    Full Text Available The paper presents radical new urban transportation system concepts, potentially allowing changing the economic and environmental costs of passenger and freight transportation. The driver focuses on the concept of sharing, which means to make a joint use of transport resources, between passengers and goods flows. From a field observation of several existing solutions, an inductive reasoning enables us to move from a set of specific facts to establish an archetype for a radical new urban transportation system. Once the archetype defined, it is translated in real life through the example of the On Route proposal for London.The research frame of this paper is the ANR ( French National Research Agency C-Goods (City Goods Operation Optimization using Decision support System project. Started in February 2009 the project involves four partners, (The multi-disciplinary French engineer school EIGSI (Ecole d’Ingénieurs en Génie des Systèmes Industriels, the French university ENMP (Ecole Nationale Supérieure des Mines de Paris, the Poitiers Urban Community (CAP, and the consulting service Interface Transport, specialized in transport economy and will end on 2012.

  16. Revisit to the helicity and the generalized self-organization theory

    International Nuclear Information System (INIS)

    Kondoh, Y.; Takahashi, T.; Momota, H.

    2000-09-01

    It is clarified that the so-caned 'helicity conservation law' is never the conservation equation of the helicity K itself', but is merely 'the time change rate equation of K', which is passively and resultantly determined by the mutually independent volume and surface integral terms. It is shown that since the total helicity K can never be conserved in the real experimental systems, the conjecture of the total helicity invariance is not physically available to real magnetized plasmas in an exact sense. The well-known relaxation theory by Dr. J. B. Taylor is clarified to be neither the variational principle nor the energy principle, but be merely a mathematical calculation, using the variational calculus in order to find the minimum magnetic energy solution from the set of solutions having the same value of K. With the use of auto-correlations for physical quantities, it is presented that a novel basic formulation of an extended generalized self-organization theory, which is not based on neither the variational principle nor the energy principle. It is clarified that conservation equations concerning with all physical quantities for the dynamic system of interest are naturally embedded in the formulation of the generalized self-organization theory. The self-organized states of every physical quantities of interest may be realized during their own phases and the dynamical system may evolve repeatedly those out of phase organizations, depending on boundary conditions and input powers. It is shown that the conservation laws can be used to extend conventional methods of plasma current drives by energy injections with use of various types of energies, such as magnetic energies, electromagnetic wave energies, internal energies of plasmoids by plasma guns, which induce the thermal plasma flow velocity, various particle beam energies, and so on. (author)

  17. Revisit to the helicity and the generalized self-organization theory

    Energy Technology Data Exchange (ETDEWEB)

    Kondoh, Y.; Takahashi, T. [Dept. of Electronic Engineering, Gunma Univ., Kiryu, Gunma (Japan); Momota, H. [Illinois Univ., Illinois (United States)

    2000-09-01

    It is clarified that the so-caned 'helicity conservation law' is never the conservation equation of the helicity K itself', but is merely 'the time change rate equation of K', which is passively and resultantly determined by the mutually independent volume and surface integral terms. It is shown that since the total helicity K can never be conserved in the real experimental systems, the conjecture of the total helicity invariance is not physically available to real magnetized plasmas in an exact sense. The well-known relaxation theory by Dr. J. B. Taylor is clarified to be neither the variational principle nor the energy principle, but be merely a mathematical calculation, using the variational calculus in order to find the minimum magnetic energy solution from the set of solutions having the same value of K. With the use of auto-correlations for physical quantities, it is presented that a novel basic formulation of an extended generalized self-organization theory, which is not based on neither the variational principle nor the energy principle. It is clarified that conservation equations concerning with all physical quantities for the dynamic system of interest are naturally embedded in the formulation of the generalized self-organization theory. The self-organized states of every physical quantities of interest may be realized during their own phases and the dynamical system may evolve repeatedly those out of phase organizations, depending on boundary conditions and input powers. It is shown that the conservation laws can be used to extend conventional methods of plasma current drives by energy injections with use of various types of energies, such as magnetic energies, electromagnetic wave energies, internal energies of plasmoids by plasma guns, which induce the thermal plasma flow velocity, various particle beam energies, and so on. (author)

  18. Modeling of Instabilities and Self-organization at the Frictional Interface

    Science.gov (United States)

    Mortazavi, Vahid

    The field of friction-induced self-organization and its practical importance remains unknown territory to many tribologists. Friction is usually thought of as irreversible dissipation of energy and deterioration; however, under certain conditions, friction can lead to the formation of new structures at the interface, including in-situ tribofilms and various patterns at the interface. This thesis studies self-organization and instabilities at the frictional interface, including the instability due to the temperature-dependency of the coefficient of friction, the transient process of frictional running-in, frictional Turing systems, the stick-and-slip phenomenon, and, finally, contact angle (CA) hysteresis as an example of solid-liquid friction and dissipation. All these problems are chosen to bridge the gap between fundamental interest in understanding the conditions leading to self-organization and practical motivation. We study the relationship between friction-induced instabilities and friction-induced self-organization. Friction is usually thought of as a stabilizing factor; however, sometimes it leads to the instability of sliding, in particular when friction is coupled with another process. Instabilities constitute the main mechanism for pattern formation. At first, a stationary structure loses its stability; after that, vibrations with increasing amplitude occur, leading to a limit cycle corresponding to a periodic pattern. The self-organization is usually beneficial for friction and wear reduction because the tribological systems tend to enter a state with the lowest energy dissipation. The introductory chapter starts with basic definitions related to self-organization, instabilities and friction, literature review, and objectives. We discuss fundamental concepts that provide a methodological tool to investigate, understand and enhance beneficial processes in tribosystems which might lead to self-organization. These processes could result in the ability of a

  19. Self-organization as the cause of different states of dc and hf discharge plasmas

    International Nuclear Information System (INIS)

    Lozneanu, E.; Dimitriu, D.; Gaman, C.; Furtuna, C.; Filep, E.; Sanduloviciu, M.

    2004-01-01

    Dc and hf gas discharges used in industrial devices are strongly nonlinear media whose characteristics and behavior critically depend on the type of the device and on the way and the amount of energy injected into the system. Consequently, considering a certain industrial device, it is possible to select, by gradually changing the injected energy, the working regimes that offer the most suitable conditions for a certain practical applications. The consideration of the nonlinear behavior of gaseous conductors (plasmas), created in dc and hf electric fields, and implicitly of the self-organizing phenomena at their origin become important for certain applications (Authors)

  20. Influence of Selective Edge Removal and Refractory Period in a Self-Organized Critical Neuron Model

    International Nuclear Information System (INIS)

    Lin Min; Gang, Zhao; Chen Tianlun

    2009-01-01

    A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system. (condensed matter: structural, mechanical, and thermal properties)

  1. Clustering Multiple Sclerosis Subgroups with Multifractal Methods and Self-Organizing Map Algorithm

    Science.gov (United States)

    Karaca, Yeliz; Cattani, Carlo

    Magnetic resonance imaging (MRI) is the most sensitive method to detect chronic nervous system diseases such as multiple sclerosis (MS). In this paper, Brownian motion Hölder regularity functions (polynomial, periodic (sine), exponential) for 2D image, such as multifractal methods were applied to MR brain images, aiming to easily identify distressed regions, in MS patients. With these regions, we have proposed an MS classification based on the multifractal method by using the Self-Organizing Map (SOM) algorithm. Thus, we obtained a cluster analysis by identifying pixels from distressed regions in MR images through multifractal methods and by diagnosing subgroups of MS patients through artificial neural networks.

  2. Renormalization group and instantons in stochastic nonlinear dynamics, from self-organized criticality to thermonuclear reactors

    International Nuclear Information System (INIS)

    Volchenkov, D.

    2009-01-01

    Stochastic counterparts of nonlinear dynamics are studied by means of nonperturbative functional methods developed in the framework of quantum field theory (QFT). In particular, we discuss fully developed turbulence, including leading corrections on possible compressibility of fluids, transport through porous media, theory of waterspouts and tsunami waves, stochastic magnetohydrodynamics, turbulent transport in crossed fields, self-organized criticality, and dynamics of accelerated wrinkled flame fronts advancing in a wide canal. This report would be of interest to the broad auditorium of physicists and applied mathematicians, with a background in nonperturbative QFT methods or nonlinear dynamical systems, having an interest in both methodological developments and interdisciplinary applications. (author)

  3. Renormalization group and instantons in stochastic nonlinear dynamics, from self-organized criticality to thermonuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Volchenkov, D. [Bielefeld Univ., Center of Excellence Cognitive Interaction Technology (CITEC) (Germany)

    2009-03-15

    Stochastic counterparts of nonlinear dynamics are studied by means of nonperturbative functional methods developed in the framework of quantum field theory (QFT). In particular, we discuss fully developed turbulence, including leading corrections on possible compressibility of fluids, transport through porous media, theory of waterspouts and tsunami waves, stochastic magnetohydrodynamics, turbulent transport in crossed fields, self-organized criticality, and dynamics of accelerated wrinkled flame fronts advancing in a wide canal. This report would be of interest to the broad auditorium of physicists and applied mathematicians, with a background in nonperturbative QFT methods or nonlinear dynamical systems, having an interest in both methodological developments and interdisciplinary applications. (author)

  4. On the genesis of spatio-temporal self-organized structures in plasma devices

    International Nuclear Information System (INIS)

    Talasman, S.J.; Sanduloviciu, M.

    1995-01-01

    The genesis of luminous sharply defined nearly spherical space charges structures formed in an Argon plasma column was experimental investigated. The results reveal spatio-temporal characteristics proper to systems resulting after a self-organization process. Their phenomenology involves electrical charges separation produced by symmetry breaking and spatial separation of the excitation and ionization cross sections functions in a region where electrons are accelerated and, as a result, the appearance of electrostatic forces that, acting as long range correlations, assures, together with dissipative effects, its stability. (Author) 8 Figs., 31 Refs

  5. Macromolecular target prediction by self-organizing feature maps.

    Science.gov (United States)

    Schneider, Gisbert; Schneider, Petra

    2017-03-01

    Rational drug discovery would greatly benefit from a more nuanced appreciation of the activity of pharmacologically active compounds against a diverse panel of macromolecular targets. Already, computational target-prediction models assist medicinal chemists in library screening, de novo molecular design, optimization of active chemical agents, drug re-purposing, in the spotting of potential undesired off-target activities, and in the 'de-orphaning' of phenotypic screening hits. The self-organizing map (SOM) algorithm has been employed successfully for these and other purposes. Areas covered: The authors recapitulate contemporary artificial neural network methods for macromolecular target prediction, and present the basic SOM algorithm at a conceptual level. Specifically, they highlight consensus target-scoring by the employment of multiple SOMs, and discuss the opportunities and limitations of this technique. Expert opinion: Self-organizing feature maps represent a straightforward approach to ligand clustering and classification. Some of the appeal lies in their conceptual simplicity and broad applicability domain. Despite known algorithmic shortcomings, this computational target prediction concept has been proven to work in prospective settings with high success rates. It represents a prototypic technique for future advances in the in silico identification of the modes of action and macromolecular targets of bioactive molecules.

  6. Self-organizing magnetic beads for biomedical applications

    International Nuclear Information System (INIS)

    Gusenbauer, Markus; Kovacs, Alexander; Reichel, Franz; Exl, Lukas; Bance, Simon; Özelt, Harald; Schrefl, Thomas

    2012-01-01

    In the field of biomedicine magnetic beads are used for drug delivery and to treat hyperthermia. Here we propose to use self-organized bead structures to isolate circulating tumor cells using lab-on-chip technologies. Typically blood flows past microposts functionalized with antibodies for circulating tumor cells. Creating these microposts with interacting magnetic beads makes it possible to tune the geometry in size, position and shape. We developed a simulation tool that combines micromagnetics and discrete particle dynamics, in order to design micropost arrays made of interacting beads. The simulation takes into account the viscous drag of the blood flow, magnetostatic interactions between the magnetic beads and gradient forces from external aligned magnets. We developed a particle–particle particle–mesh method for effective computation of the magnetic force and torque acting on the particles. - Highlights: ► We propose to use self-organized bead structures to isolate circulating tumor cells. ► Flexible ways are important to get a high probability of catching cancer cells. ► The beads make it possible to tune the geometry in size position and shape.

  7. Classification of perovskites with supervised self-organizing maps

    International Nuclear Information System (INIS)

    Kuzmanovski, Igor; Dimitrovska-Lazova, Sandra; Aleksovska, Slobotka

    2007-01-01

    In this work supervised self-organizing maps were used for structural classification of perovskites. For this purpose, structural data for total number of 286 perovskites, belonging to ABO 3 and/or A 2 BB'O 6 types, were collected from literature: 130 of these are cubic, 85 orthorhombic and 71 monoclinic. For classification purposes, the effective ionic radii of the cations, electronegativities of the cations in B-position, as well as, the oxidation states of these cations, were used as input variables. The parameters of the developed models, as well as, the most suitable variables for classification purposes were selected using genetic algorithms. Two-third of all the compounds were used in the training phase. During the optimization process the performances of the models were checked using cross-validation leave-1/10-out. The performances of obtained solutions were checked using the test set composed of the remaining one-third of the compounds. The obtained models for classification of these three classes of perovskite compounds show very good results. Namely, the classification of the compounds in the test set resulted in small number of discrepancies (4.2-6.4%) between the actual crystallographic class and the one predicted by the models. All these results are strong arguments for the validity of supervised self-organizing maps for performing such types of classification. Therefore, the proposed procedure could be successfully used for crystallographic classification of perovskites in one of these three classes

  8. SELF-ORGANIZATION OF LEAD SULFIDE QUANTUM DOTS INTO SUPERSTRUCTURES

    Directory of Open Access Journals (Sweden)

    Elena V. Ushakova

    2014-11-01

    Full Text Available The method of X-ray structural analysis (X-ray scattering at small angles is used to show that the structures obtained by self-organization on a substrate of lead sulfide (PbS quantum dots are ordered arrays. Self-organization of quantum dots occurs at slow evaporation of solvent from a cuvette. The cuvette is a thin layer of mica with teflon ring on it. The positions of peaks in SAXS pattern are used to calculate crystal lattice of obtained ordered structures. Such structures have a primitive orthorhombic crystal lattice. Calculated lattice parameters are: a = 21,1 (nm; b = 36,2 (nm; c = 62,5 (nm. Dimensions of structures are tens of micrometers. The spectral properties of PbS QDs superstructures and kinetic parameters of their luminescence are investigated. Absorption band of superstructures is broadened as compared to the absorption band of the quantum dots in solution; the luminescence band is slightly shifted to the red region of the spectrum, while its bandwidth is not changed much. Luminescence lifetime of obtained structures has been significantly decreased in comparison with the isolated quantum dots in solution, but remained the same for the lead sulfide quantum dots close-packed ensembles. Such superstructures can be used to produce solar cells with improved characteristics.

  9. Self-organization in cathode boundary layer discharges in xenon

    International Nuclear Information System (INIS)

    Takano, Nobuhiko; Schoenbach, Karl H

    2006-01-01

    Self-organization of direct current xenon microdischarges in cathode boundary layer configuration has been studied for pressures in the range 30-140 Torr and for currents in the range 50 μA-1 mA. Side-on and end-on observations of the discharge have provided information on the structure and spatial arrangement of the plasma filaments. The regularly spaced filaments, which appear in the normal glow mode when the current is lowered, have a length which is determined by the cathode fall. It varies, dependent on pressure and current, between 50 and 70 μm. The minimum diameter is approximately 80 μm, as determined from the radiative emission in the visible. The filaments are sources of extensive excimer emission. Measurements of the cathode fall length have allowed us to determine the secondary emission coefficient for the discharge in the normal glow mode and to estimate the cathode fall voltage at the transition from normal glow mode to filamentary mode. It was found that the cathode fall voltage at this transition decreases, indicating the onset of additional electron gain processes at the cathode. The regular arrangement of the filaments, self-organization, is assumed to be due to Coulomb interactions between the positively charged cathode fall channels and positive space charges on the surface of the surrounding dielectric spacer. Calculations based on these assumptions showed good agreement with experimentally observed filament patterns

  10. Obtaining parton distribution functions from self-organizing maps

    International Nuclear Information System (INIS)

    Honkanen, H.; Liuti, S.; Loitiere, Y.C.; Brogan, D.; Reynolds, P.

    2007-01-01

    We present an alternative algorithm to global fitting procedures to construct Parton Distribution Functions parametrizations. The proposed algorithm uses Self-Organizing Maps which at variance with the standard Neural Networks, are based on competitive-learning. Self-Organizing Maps generate a non-uniform projection from a high dimensional data space onto a low dimensional one (usually 1 or 2 dimensions) by clustering similar PDF representations together. The SOMs are trained on progressively narrower selections of data samples. The selection criterion is that of convergence towards a neighborhood of the experimental data. All available data sets on deep inelastic scattering in the kinematical region of 0.001 ≤ x ≤ 0.75, and 1 ≤ Q 2 ≤ 100 GeV 2 , with a cut on the final state invariant mass, W 2 ≥ 10 GeV 2 were implemented. The proposed fitting procedure, at variance with standard neural network approaches, allows for an increased control of the systematic bias by enabling the user to directly control the data selection procedure at various stages of the process. (author)

  11. Informational temperature concept and the nature of self-organization

    International Nuclear Information System (INIS)

    Lin, Shu-Kun

    1996-01-01

    Self-organization phenomena are spontaneous processes. Their behavior should be governed by the second law of thermodynamics. The dissipative structure theory of the Prigogine school of thermodynamics claims that open-quotes order out of chaosclose quotes through open-quotes self-organizationclose quotes and challenges the validity of the second law of thermodynamics. Unfortunately this theory is questionable. Therefore we have to reconsider the related fundamental theoretical problems. Informational entropy (S) and information (I) are related by S = S max - I, where S max is the maximum informational entropy. This conforms with the broadly accepted definition that entropy is the information loss. As informational entropy concept has been proved to be useful, it will be convenient to define an informational temperature, T I . This can be related to energy E and the informational entropy S. Information registration is a process of ΔI > 0, or ΔS 0). Therefore, T I is negative, and has the opposite sign of the conventional thermodynamic temperature, T. This concept is useful for clarifying the concepts of open-quotes orderclose quotes and open-quotes disorderclose quotes of static structures and characterizing many typical information loss processes of self-organization

  12. ADVANCED DRIVER SAFETY SUPPORT SYSTEMS FOR THE URBAN TYPE VEHICLE

    Directory of Open Access Journals (Sweden)

    Katarzyna JEZIERSKA-KRUPA

    2015-12-01

    Full Text Available Smart Power Team is currently working on the design of an urban electric vehicle designed to compete in the Shell Eco-marathon. One important aspect of this type of vehicle characteristics is it safety. The project of advanced driver assistance systems has included some proposals of such systems and the concept of their execution. The first concept, BLIS (Blind Spot Information System, is to build a system of informing a driver about vehicles appearing in the blind spot. The system constitutes a second concept, CDIS (Collision Detection and Information System, and it is designed to detect a vehicle collision and inform the team. Further systems are: DPMS (Dew Point Measurement System - a system which does not allow a situation, where the windows are fogged, OHRS (Overtaking Horn Reminder System - a system which checks overtaking and MSS (main supervision system - a supervisory system. These concepts are based on the assumption of the use of laser sensors, photoelectric, humidity and temperature, and other commercially available systems. The article presents a detailed description of driver assistance systems and virtual prototyping methodology for these systems, as well as the numerical results of the verification of one of the systems.

  13. Flood forecasting within urban drainage systems using NARX neural network.

    Science.gov (United States)

    Abou Rjeily, Yves; Abbas, Oras; Sadek, Marwan; Shahrour, Isam; Hage Chehade, Fadi

    2017-11-01

    Urbanization activity and climate change increase the runoff volumes, and consequently the surcharge of the urban drainage systems (UDS). In addition, age and structural failures of these utilities limit their capacities, and thus generate hydraulic operation shortages, leading to flooding events. The large increase in floods within urban areas requires rapid actions from the UDS operators. The proactivity in taking the appropriate actions is a key element in applying efficient management and flood mitigation. Therefore, this work focuses on developing a flooding forecast system (FFS), able to alert in advance the UDS managers for possible flooding. For a forecasted storm event, a quick estimation of the water depth variation within critical manholes allows a reliable evaluation of the flood risk. The Nonlinear Auto Regressive with eXogenous inputs (NARX) neural network was chosen to develop the FFS as due to its calculation nature it is capable of relating water depth variation in manholes to rainfall intensities. The campus of the University of Lille is used as an experimental site to test and evaluate the FFS proposed in this paper.

  14. An integrated urban drainage system model for assessing renovation scheme.

    Science.gov (United States)

    Dong, X; Zeng, S; Chen, J; Zhao, D

    2012-01-01

    Due to sustained economic growth in China over the last three decades, urbanization has been on a rapidly expanding track. In recent years, regional industrial relocations were also accelerated across the country from the east coast to the west inland. These changes have led to a large-scale redesign of urban infrastructures, including the drainage system. To help the reconstructed infrastructures towards a better sustainability, a tool is required for assessing the efficiency and environmental performance of different renovation schemes. This paper developed an integrated dynamic modeling tool, which consisted of three models for describing the sewer, the wastewater treatment plant (WWTP) and the receiving water body respectively. Three auxiliary modules were also incorporated to conceptualize the model, calibrate the simulations, and analyze the results. The developed integrated modeling tool was applied to a case study in Shenzhen City, which is one of the most dynamic cities and facing considerable challenges for environmental degradation. The renovation scheme proposed to improve the environmental performance of Shenzhen City's urban drainage system was modeled and evaluated. The simulation results supplied some suggestions for the further improvement of the renovation scheme.

  15. Large Scale Self-Organizing Information Distribution System

    National Research Council Canada - National Science Library

    Low, Steven

    2005-01-01

    This project investigates issues in "large-scale" networks. Here "large-scale" refers to networks with large number of high capacity nodes and transmission links, and shared by a large number of users...

  16. Strain relaxation and self-organization phenomena in heteroepitaxial systems

    DEFF Research Database (Denmark)

    Shiryaev, Sergey Y; Hansen, J. Lundsgaard; Larsen, A. Nylandsted

    1995-01-01

    The plastic behavior of strained, compositionally graded Si1-xGex alloy layers grown on Si substrates has been studied by a combination of optical, atomic force, and transmission electron microscopy. Formation of ordered patterns of misfit dislocations has been found in films grown at low (simila...

  17. Self-organization of turbulence. A brief review of self-organization with particular reference to hydrodynamic and magnetohydrodynamic turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, A [Bell Labs., Murray Hill, NJ (USA)

    1982-02-01

    Theoretical treatments of turbulence in fluids and plasmas often assume that the turbulence is isotropic and homogeneous. It is also often considered that turbulence produces uniformly distributed chaos, even when starting with a coherent initial condition. Recently, however, phenomena which do not obey these classic concepts have emerged. For example, in two-dimensional Navier-Stokes turbulence, an organized flow or structure is found to appear even from a chaotic initial condition. The author attempts to review some of the recent developments of a phenomenon called self-organization in the field of hydrodynamics and plasma physics.

  18. Urban underground logistics system in China: Opportunities or challenges?

    Directory of Open Access Journals (Sweden)

    Zhilong Chen

    2017-09-01

    Full Text Available An urban underground logistics system (ULS is one important means of solving urban traffic problems that has unique advantages. Freight transportation in China requires a new transportation mode. Therefore, ULS has garnered increasing attention. However, to date, few scholars and practitioners have investigated ULS in China. Although ULS shows good development opportunities, it also faces great challenges. Based on the Macro-environment and situation analysis (PEST-SWOT model, which is a strategic analysis method that combines both SWOT and PEST to effectively identify advantages, disadvantages, opportunities and threats, this paper first uses PEST to analyze the macro-environment of ULS in China and identify its internal factors (i.e., advantages and disadvantages and external factors (i.e., opportunities and threats. Next, based on the SWOT framework, this paper proposes several development strategies and recommendations that provide a comprehensive and novel perspective to the study of ULS in China.

  19. Self-organized ignition of a tokamak plasma

    International Nuclear Information System (INIS)

    Schoepf, K.

    2007-01-01

    The continuous progress in the attainment of plasma parameters required for establishing nuclear fusion in magnetically confined plasmas as well as the prospect of feasible steady-state operation has instigated the interest in the physics of burning plasmas [1]. Aside from the required plasma current drive, fusion energy production with tokamaks demands particular attention to confinement and fuelling regimes in order to maintain the plasma density n and temperature T at favourable values matching with specific requirements such as the triple product nτ E T, where τ E represents the plasma energy confinement time. The identification of state and parameter space regions capable of ignited fusion plasma operation is evidently crucial if significant energy gains are to be realized over longer periods. Examining the time-evolving state of tokamak fusion plasma in a parameter space spanned by the densities of plasma constituents and their temperatures has led to the formation of an ignition criterion [2] fundamentally different from the commonly used static patterns. The incorporation of non-stationary particle and energy balances into the analysis here, the application of a 'soft' Troyon beta limit [3], the consideration of actual fusion power deposition [4,5] and its effect of reducing τ E are seen to significantly influence the fusion burn dynamics and to shape the ignition conditions. The presented investigation refers to a somewhat upgraded (to achieve ignition) ITER-like tokamak plasma and uses volume averages of locally varying quantities and processes. The resulting ignition criterion accounts for the dynamic evolution of a reacting plasma controlled by heating and fuel feeding. Interestingly, also self-organized ignition can be observed: a fusion plasma possessing a density and temperature above a distinct separatrix in the considered parameter phase space is seen to evolve - without external heating and hence practically by itself - towards an ignited

  20. Urban Systems and Energy Consumptions: A Critical Approach

    Directory of Open Access Journals (Sweden)

    Rocco Papa

    2014-05-01

    Full Text Available City transformations are also due to the development of new energy sources, which have influenced economy and lifestyles, as well as the physical and functional organization of urban systems. Cities are the key place where it is need to act for the achievement of strategic environmental objectives, such as reducing greenhouse gas emissions and energy saving. The hard resolution of these challenges depends on several factors: their multidimensional nature, the change of the economic and settlement development model, and also the complexity of the relationships between the elements that constitute the urban systems and that affect energy consumption. According to this awareness the Project Smart Energy Master for the energy management of territory financed by PON 04A2_00120 R & C Axis II, from 2012 to 2015 has been developed: it is aimed at supporting local authorities in the development of strategies for the reduction of energy consumption through actions designed to change behavior (in terms of use and energy consumption and to improve the energy efficiency of equipment and infrastructure. With the goal of describing some of the results of the methodological phase of this project, this paper proposes a review of the major studies on the issue of energy consumption at the urban scale in the first section; in the second section the outcomes of the first phase of the development of the comprehension/interpretive model related to the identification of the set of physical/environmental variables at urban scale, that most affect the energy consumption, are described; the third makes a critical review of the reference scientific literature, characterised by a too sectoral approach, compared to the complexity of the topic.

  1. Scaling, phase transitions, and nonuniversality in a self-organized critical cellular-automaton model

    International Nuclear Information System (INIS)

    Christensen, K.; Olami, Z.

    1992-01-01

    We present a two-dimensional continuous cellular automaton that is equivalent to a driven spring-block model. Both the conservation and the anisotropy in the model are controllable quantities. Above a critical level of conservation, the model exhibits self-organized criticality. The self-organization of this system and hence the critical exponents depend on the conservation and the boundary conditions. In the critical isotropic nonconservative phase, the exponents change continuously as a function of conservation. Furthermore, the exponents vary continuously when changing the boundary conditions smoothly. Consequently, there is no universality of the critical exponents. We discuss the relevance of this for earthquakes. Introducing anisotropy changes the scaling of the distribution function, but not the power-law exponent. We explore the phase diagram of this model. We find that at low conservation levels a localization transition occurs. We see two additional phase transitions. The first is seen when moving from the conservative into the nonconservative model. The second appears when passing from the anisotropic two-dimensional system to the purely one-dimensional system

  2. Computational modeling of neural plasticity for self-organization of neural networks.

    Science.gov (United States)

    Chrol-Cannon, Joseph; Jin, Yaochu

    2014-11-01

    Self-organization in biological nervous systems during the lifetime is known to largely occur through a process of plasticity that is dependent upon the spike-timing activity in connected neurons. In the field of computational neuroscience, much effort has been dedicated to building up computational models of neural plasticity to replicate experimental data. Most recently, increasing attention has been paid to understanding the role of neural plasticity in functional and structural neural self-organization, as well as its influence on the learning performance of neural networks for accomplishing machine learning tasks such as classification and regression. Although many ideas and hypothesis have been suggested, the relationship between the structure, dynamics and learning performance of neural networks remains elusive. The purpose of this article is to review the most important computational models for neural plasticity and discuss various ideas about neural plasticity's role. Finally, we suggest a few promising research directions, in particular those along the line that combines findings in computational neuroscience and systems biology, and their synergetic roles in understanding learning, memory and cognition, thereby bridging the gap between computational neuroscience, systems biology and computational intelligence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. QUALITATIVE ANALYSIS OF OFFICIAL MILK CONTROL IN VALENCIA COMMUNITY (SPAIN BY SELF ORGANIZING MAPS

    Directory of Open Access Journals (Sweden)

    Carlos Javier Fernandez

    2009-06-01

    Full Text Available Breeding programs in dairy goats are mainly based on milk production and composition. Murciano-Granadina goats are located principally in the central and southern regions of Spain. This study is focused in Valencia Community (Spain and the objective is to study the Murciano-Granadina livestock based on the database from Murciano-Granadina Goat Breeders Association of Valencia (AMURVAL.  The aim of this study is to analyze the relationship among different variables related with milk production; milk yield, fat, protein, lactose, SCC, the number of births, lactation number and season. This analysis is carried out by using the Self Organizing Map. This tool allows mapping high-dimensional input spaces into much lower-dimensional spaces, thus making much more straightforward to understand any representation of data. These representations enable to visually extract qualitative relationships among variables (Visual Data Mining. A total of 3221 Murciano-Granadina dairy goats from AMURVAL were chosen. Self Organizing Maps (SOM were used to analyze data with the system identification toolbox of MATLAB v7. Data were obtained from Official Milk Control during 2006 campaign. SOM considered in this study is formed by 21´14 neurons (294 neurons; the chosen architecture is given by the range of the input variables used. The map shown that more than 70% of the goats has milk yield greater than 300 kg per lactation and goat, indicating good performance of farms. Besides, the SOM obtained indicate a group of neurons that included goats with high SSC (2%. The use of Self Organizing Maps in the descriptive analysis of this kind of data sets has proven to be highly valuable in extracting qualitative conclusions and guiding in improving the performance of farms.

  4. Self-organized structures in a superorganism: do ants “behave” like molecules?

    Science.gov (United States)

    Detrain, Claire; Deneubourg, Jean-Louis

    2006-09-01

    While the striking structures (e.g. nest architecture, trail networks) of insect societies may seem familiar to many of us, the understanding of pattern formation still constitutes a challenging problem. Over the last two decades, self-organization has dramatically changed our view on how collective decision-making and structures may emerge out of a population of ant workers having each their own individuality as well as a limited access to information. A variety of collective behaviour spontaneously outcome from multiple interactions between nestmates, even when there is no directing influence imposed by an external template, a pacemaker or a leader. By focussing this review on foraging structures, we show that ant societies display some properties which are usually considered in physico-chemical systems, as typical signatures of self-organization. We detail the key role played by feed-back loops, fluctuations, number of interacting units and sensitivity to environmental factors in the emergence of a structured collective behaviour. Nonetheless, going beyond simple analogies with non-living self-organized patterns, we stress on the specificities of social structures made of complex living units of which the biological features have been selected throughout the evolution depending on their adaptive value. In particular, we consider the ability of each ant individual to process information about environmental and social parameters, to accordingly tune its interactions with nestmates and ultimately to determine the final pattern emerging at the collective level. We emphasize on the parsimony and simplicity of behavioural rules at the individual level which allow an efficient processing of information, energy and matter within the whole colony.

  5. Self-Organized Governance Networks for Ecosystem Management: Who Is Accountable?

    Directory of Open Access Journals (Sweden)

    Thomas Hahn

    2011-06-01

    Full Text Available Governance networks play an increasingly important role in ecosystem management. The collaboration within these governance networks can be formalized or informal, top-down or bottom-up, and designed or self-organized. Informal self-organized governance networks may increase legitimacy if a variety of stakeholders are involved, but at the same time, accountability becomes blurred when decisions are taken. Basically, democratic accountability refers to ways in which citizens can control their government and the mechanisms for doing so. Scholars in ecosystem management are generally positive to policy/governance networks and emphasize its potential for enhancing social learning, adaptability, and resilience in social-ecological systems. Political scientists, on the other hand, have emphasized the risk that the public interest may be threatened by governance networks. I describe and analyze the multilevel governance network of Kristianstads Vattenrike Biosphere Reserve (KVBR in Southern Sweden, with the aim of understanding whether and how accountability is secured in the governance network and its relation to representative democracy. The analysis suggests that the governance network of KVBR complements representative democracy. It deals mainly with "low politics"; the learning and policy directions are developed in the governance network, but the decisions are embedded in representative democratic structures. Because several organizations and agencies co-own the process and are committed to the outcomes, there is a shared or extended accountability. A recent large investment in KVBR caused a major crisis at the municipal level, fueled by the financial crisis. The higher levels of the governance network, however, served as a social memory and enhanced resilience of the present biosphere development trajectory. For self-organized networks, legitimacy is the bridge between adaptability and accountability; accountability is secured as long as the

  6. THE STRESS RESISTANCE OF STUDENTS. THE PARADIGM OF SUBJECT PERSONALITY SELF- ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Sergey I. Dyakov

    2016-01-01

    Full Text Available The aim of the investigation is to consider a problem of stress resistance of students in the context of subject self-organization of the personality. Methods. The following methods of research are used: questioning; psychological and diagnostic tests «Tolerance of Uncertainty» (NTN and «Personal Factors of Decisions» (PFD by T. V. Kornilova; original experimental experiences – «Coding», a technique of a self-assessment (scaling and «A locus control». While data processing the methods of mathematical statistics (SPSS 12 package – the correlation analysis of Pearson and the factorial analysis with rotation use a component by «verimax» method are applied. Results and scientific novelty. Types of subjectivity and strategy of stress resistance are allocated. The nature and a role of the emotional and stressful mechanism having information and semantic properties in its basis are disclosed. Communication of irresponsible mechanisms of mentality with the sphere of consciousness in the context of subjectivity of the personality is shown. Mechanisms of emotional and rational self-control of system of mental self-organization of the person are presented. The statistical and qualitative data opening communications between properties of subjectivity and stress resistance of the personality are empirically obtained. Variation of the relations and also types of subjectivity and stress resistance emphasized based on the results of the presented research. Original (author’s methods of studying of subjectivity and factors of stress resistance are presented. Practical significance. The revealed factors of subject self-organization reveal the stress-producing directions of the environment and the relation of the personality to situations of changes and uncertainty: and also indicate subject properties of resistance to stress which need to be developed to increase the level of health of students, to reduce risk of deviance and delinquency of

  7. Is there a self-organization principle of river deltas?

    Science.gov (United States)

    Tejedor, Alejandro; Longjas, Anthony; Foufoula-Georgiou, Efi

    2017-04-01

    River deltas are known to possess a complex topological and flux-partitioning structure which has recently been quantified using spectral graph theory [Tejedor et al., 2015a,b]. By analysis of real and simulated deltas it has also been shown that there is promise in formalizing relationships between this topo-dynamic delta structure and the underlying delta forming processes [e.g., Tejedor et al., 2016]. The question we pose here is whether there exists a first order organizational principle behind the self-organization of river deltas and whether this principle can be unraveled from the co-evolving topo-dynamic structure encoded in the delta planform. To answer this question, we introduce a new metric, the nonlocal Entropy Rate (nER) that captures the information content of a delta network in terms of the degree of uncertainty in delivering fluxes from any point of the network to the shoreline. We hypothesize that if the "guiding principle" of undisturbed deltas is to efficiently and robustly build land by increasing the diversity of their flux pathways over the delta plane, then they would exhibit maximum nonlocal Entropy Rate at states at which geometry and flux dynamics are at equilibrium. At the same time, their nER would be non-optimal at transient states, such as before and after major avulsions during which topology and dynamics adjust to each other to reach a new equilibrium state. We will present our results for field and simulated deltas, which confirm this hypothesis and open up new ways of thinking about self-organization, complexity and robustness in river deltas. One particular connection of interest might have important implications since entropy rate and resilience are related by the fluctuation theorem [Demetrius and Manke, 2005], and therefore our results suggest that deltas might in fact self-organize to maximize their resilience to structural and dynamic perturbations. References: Tejedor, A., A. Longjas, I. Zaliapin, and E. Foufoula

  8. Urban Environmental Education for Global Transformation Initiatives - Integrating Information and Communication Systems for Urban Sustainability in 2050.

    Science.gov (United States)

    Chaudhari, K.

    2017-12-01

    The Urban population of developing countries is predicted to rise from one third in 1990 to over 50% by 2025. In 1950 the world's total urban population was 734 million, of whom 448 million were living in developed countries and remaining 286 were in developing region. The total population on earth is predicted to increase by more than one billion people within the next 15 years, reaching 8.5 billion in 2030, and to increase further to 9.7 billion in 2050 and 11.2 billion by 2100. Looking at the ever increasing urbanization.In 2016, an estimated 54.5 per cent of the world's populations inhabited in urban region. By 2030, urban areas are projected to shelter 60 per cent of people worldwide and one in every three people will live in cities with at least half a million inhabitants.On the basis of these figures and other global trends, it would appear that Africa and Asia will have the highest share of world's urban growth in next 25 years, resulting consideration rise of large number of metropolitan cities and towns. Therefore issues related to urban climate change will be important for socio economic development for urban transformation through environmental sustainability.The information and communication systems plays an important role in achieving the social sustainability through environmental sustainability for urban transformation. This presentation aims to start the Global initiatives on the problem identifications in environment education for global transformation, education for socio-economic and environmental sustainability due to urbanization in 2050 to investigate problems related to social-economic risks and management issues resulting from urbanization to aid mitigation planning in globalized world and to educate scientists and local populations to form a basis for sustainable solutions in environment learning.The presentation aims to assess the potential of information and communication technology for environment education,both within different

  9. Sustainable Water Management in Urban, Agricultural, and Natural Systems

    Directory of Open Access Journals (Sweden)

    Tess Russo

    2014-12-01

    Full Text Available Sustainable water management (SWM requires allocating between competing water sector demands, and balancing the financial and social resources required to support necessary water systems. The objective of this review is to assess SWM in three sectors: urban, agricultural, and natural systems. This review explores the following questions: (1 How is SWM defined and evaluated? (2 What are the challenges associated with sustainable development in each sector? (3 What are the areas of greatest potential improvement in urban and agricultural water management systems? And (4 What role does country development status have in SWM practices? The methods for evaluating water management practices range from relatively simple indicator methods to integration of multiple models, depending on the complexity of the problem and resources of the investigators. The two key findings and recommendations for meeting SWM objectives are: (1 all forms of water must be considered usable, and reusable, water resources; and (2 increasing agricultural crop water production represents the largest opportunity for reducing total water consumption, and will be required to meet global food security needs. The level of regional development should not dictate sustainability objectives, however local infrastructure conditions and financial capabilities should inform the details of water system design and evaluation.

  10. Self-organized plasmonic metasurfaces for all-optical modulation

    Science.gov (United States)

    Della Valle, G.; Polli, D.; Biagioni, P.; Martella, C.; Giordano, M. C.; Finazzi, M.; Longhi, S.; Duò, L.; Cerullo, G.; Buatier de Mongeot, F.

    2015-06-01

    We experimentally demonstrate a self-organized metasurface with a polarization dependent transmittance that can be dynamically controlled by optical means. The configuration consists of tightly packed plasmonic nanowires with a large dispersion of width and height produced by the defocused ion-beam sputtering of a thin gold film supported on a silica glass. Our results are quantitatively interpreted according to a theoretical model based on the thermomodulational nonlinearity of gold and a finite-element numerical analysis of the absorption and scattering cross-sections of the nanowires. We found that the polarization sensitivity of the metasurface can be strongly enhanced by pumping with ultrashort laser pulses, leading to potential applications in ultrafast all-optical modulation and switching of light.

  11. Self-Organized Criticality Theory Model of Thermal Sandpile

    International Nuclear Information System (INIS)

    Peng Xiao-Dong; Qu Hong-Peng; Xu Jian-Qiang; Han Zui-Jiao

    2015-01-01

    A self-organized criticality model of a thermal sandpile is formulated for the first time to simulate the dynamic process with interaction between avalanche events on the fast time scale and diffusive transports on the slow time scale. The main characteristics of the model are that both particle and energy avalanches of sand grains are considered simultaneously. Properties of intermittent transport and improved confinement are analyzed in detail. The results imply that the intermittent phenomenon such as blobs in the low confinement mode as well as edge localized modes in the high confinement mode observed in tokamak experiments are not only determined by the edge plasma physics, but also affected by the core plasma dynamics. (paper)

  12. Weighted Evolving Networks with Self-organized Communities

    International Nuclear Information System (INIS)

    Xie Zhou; Wang Xiaofan; Li Xiang

    2008-01-01

    In order to describe the self-organization of communities in the evolution of weighted networks, we propose a new evolving model for weighted community-structured networks with the preferential mechanisms functioned in different levels according to community sizes and node strengths, respectively. Theoretical analyses and numerical simulations show that our model captures power-law distributions of community sizes, node strengths, and link weights, with tunable exponents of ν ≥ 1, γ > 2, and α > 2, respectively, sharing large clustering coefficients and scaling clustering spectra, and covering the range from disassortative networks to assortative networks. Finally, we apply our new model to the scientific co-authorship networks with both their weighted and unweighted datasets to verify its effectiveness

  13. Dynamical quenching and annealing in self-organization multiagent models

    Science.gov (United States)

    Burgos, E.; Ceva, Horacio; Perazzo, R. P.

    2001-07-01

    We study the dynamics of a generalized minority game (GMG) and of the bar attendance model (BAM) in which a number of agents self-organize to match an attendance that is fixed externally as a control parameter. We compare the usual dynamics used for the minority game with one for the BAM that makes a better use of the available information. We study the asymptotic states reached in both frameworks. We show that states that can be assimilated to either thermodynamic equilibrium or quenched configurations can appear in both models, but with different settings. We discuss the relevance of the parameter G that measures the value of the prize for winning in units of the fine for losing. We also provide an annealing protocol by which the quenched configurations of the GMG can progressively be modified to reach an asymptotic equilibrium state that coincides with the one obtained with the BAM.

  14. Clustering analysis of malware behavior using Self Organizing Map

    DEFF Research Database (Denmark)

    Pirscoveanu, Radu-Stefan; Stevanovic, Matija; Pedersen, Jens Myrup

    2016-01-01

    For the time being, malware behavioral classification is performed by means of Anti-Virus (AV) generated labels. The paper investigates the inconsistencies associated with current practices by evaluating the identified differences between current vendors. In this paper we rely on Self Organizing...... Map, an unsupervised machine learning algorithm, for generating clusters that capture the similarities between malware behavior. A data set of approximately 270,000 samples was used to generate the behavioral profile of malicious types in order to compare the outcome of the proposed clustering...... approach with the labels collected from 57 Antivirus vendors using VirusTotal. Upon evaluating the results, the paper concludes on shortcomings of relying on AV vendors for labeling malware samples. In order to solve the problem, a cluster-based classification is proposed, which should provide more...

  15. Dicyanovinyl sexithiophenes: self-organization and photovoltaic properties

    Energy Technology Data Exchange (ETDEWEB)

    Levichkova, Marieta; Wynands, David; Levin, Alexandr; Leo, Karl; Riede, Moritz [Institut fuer Angewandte Photophysik, TU Dresden (Germany); Walzer, Karsten; Hildebrandt, Dirk [Heliatek GmbH, Dresden (Germany); Baeuerle, Peter [Institut fuer Organische Chemie II und Neue Materialien, Universitaet Ulm (Germany); Rentenberger, Rosina [Institut fuer Physik, TU Ilmenau (Germany)

    2010-07-01

    Recently, vacuum deposited films consisting of conjugated dicyanovinyl-capped (DCV) oligothiophenes have shown significant potential as photoactive layers in small molecule solar cells. Here, we study the structural and optical properties of films of two DCV-derivatives both comprising six thiophene rings (DCV6Ts) but having different side groups. For both derivatives, neat DCV6T and mixed DCV6T:C{sub 60} films are compared using UV-VIS absorption and photoluminescence spectroscopy, X-ray diffraction (XRD), and atomic force microscopy. It is shown that the modification of the molecular structure results in a structured and red shifted absorption band, which indicates better molecular arrangement in the solid state. The improved self-organization at room temperature deposition is confirmed by XRD. Furthermore, the nanomorphology of the mixed DCV6T:C{sub 60} films is optimized using substrate heating. Bulk heterojunction solar cells with power conversion efficiencies exceeding 4% are presented.

  16. Characterization of Suicidal Behaviour with Self-Organizing Maps

    Directory of Open Access Journals (Sweden)

    José M. Leiva-Murillo

    2013-01-01

    Full Text Available The study of the variables involved in suicidal behavior is important from a social, medical, and economical point of view. Given the high number of potential variables of interest, a large population of subjects must be analysed in order to get conclusive results. In this paper, we describe a method based on self-organizing maps (SOMs for finding the most relevant variables even when their relation to suicidal behavior is strongly nonlinear. We have applied the method to a cohort with more than 8,000 subjects and 600 variables and discovered four groups of variables involved in suicidal behavior. According to the results, there are four main groups of risk factors that characterize the population of suicide attempters: mental disorders, alcoholism, impulsivity, and childhood abuse. The identification of specific subpopulations of suicide attempters is consistent with current medical knowledge and may provide a new avenue of research to improve the management of suicidal cases.

  17. Autonomous Data Collection Using a Self-Organizing Map.

    Science.gov (United States)

    Faigl, Jan; Hollinger, Geoffrey A

    2018-05-01

    The self-organizing map (SOM) is an unsupervised learning technique providing a transformation of a high-dimensional input space into a lower dimensional output space. In this paper, we utilize the SOM for the traveling salesman problem (TSP) to develop a solution to autonomous data collection. Autonomous data collection requires gathering data from predeployed sensors by moving within a limited communication radius. We propose a new growing SOM that adapts the number of neurons during learning, which also allows our approach to apply in cases where some sensors can be ignored due to a lower priority. Based on a comparison with available combinatorial heuristic algorithms for relevant variants of the TSP, the proposed approach demonstrates improved results, while also being less computationally demanding. Moreover, the proposed learning procedure can be extended to cases where particular sensors have varying communication radii, and it can also be extended to multivehicle planning.

  18. Modeling financial markets by self-organized criticality

    Science.gov (United States)

    Biondo, Alessio Emanuele; Pluchino, Alessandro; Rapisarda, Andrea

    2015-10-01

    We present a financial market model, characterized by self-organized criticality, that is able to generate endogenously a realistic price dynamics and to reproduce well-known stylized facts. We consider a community of heterogeneous traders, composed by chartists and fundamentalists, and focus on the role of informative pressure on market participants, showing how the spreading of information, based on a realistic imitative behavior, drives contagion and causes market fragility. In this model imitation is not intended as a change in the agent's group of origin, but is referred only to the price formation process. We introduce in the community also a variable number of random traders in order to study their possible beneficial role in stabilizing the market, as found in other studies. Finally, we also suggest some counterintuitive policy strategies able to dampen fluctuations by means of a partial reduction of information.

  19. Self-organized architectures from assorted DNA-framed nanoparticles

    Science.gov (United States)

    Liu, Wenyan; Halverson, Jonathan; Tian, Ye; Tkachenko, Alexei V.; Gang, Oleg

    2016-09-01

    The science of self-assembly has undergone a radical shift from asking questions about why individual components self-organize into ordered structures, to manipulating the resultant order. However, the quest for far-reaching nanomanufacturing requires addressing an even more challenging question: how to form nanoparticle (NP) structures with designed architectures without explicitly prescribing particle positions. Here we report an assembly concept in which building instructions are embedded into NPs via DNA frames. The integration of NPs and DNA origami frames enables the fabrication of NPs with designed anisotropic and selective interactions. Using a pre-defined set of different DNA-framed NPs, we show it is possible to design diverse planar architectures, which include periodic structures and shaped meso-objects that spontaneously emerge on mixing of the different topological types of NP. Even objects of non-trivial shapes, such as a nanoscale model of Leonardo da Vinci's Vitruvian Man, can be self-assembled successfully.

  20. Self-organization of progress across the century of physics

    Science.gov (United States)

    Perc, Matjaž

    2013-04-01

    We make use of information provided in the titles and abstracts of over half a million publications that were published by the American Physical Society during the past 119 years. By identifying all unique words and phrases and determining their monthly usage patterns, we obtain quantifiable insights into the trends of physics discovery from the end of the 19th century to today. We show that the magnitudes of upward and downward trends yield heavy-tailed distributions, and that their emergence is due to the Matthew effect. This indicates that both the rise and fall of scientific paradigms is driven by robust principles of self-organization. Data also confirm that periods of war decelerate scientific progress, and that the later is very much subject to globalisation.

  1. SORN: a self-organizing recurrent neural network

    Directory of Open Access Journals (Sweden)

    Andreea Lazar

    2009-10-01

    Full Text Available Understanding the dynamics of recurrent neural networks is crucial for explaining how the brain processes information. In the neocortex, a range of different plasticity mechanisms are shaping recurrent networks into effective information processing circuits that learn appropriate representations for time-varying sensory stimuli. However, it has been difficult to mimic these abilities in artificial neural network models. Here we introduce SORN, a self-organizing recurrent network. It combines three distinct forms of local plasticity to learn spatio-temporal patterns in its input while maintaining its dynamics in a healthy regime suitable for learning. The SORN learns to encode information in the form of trajectories through its high-dimensional state space reminiscent of recent biological findings on cortical coding. All three forms of plasticity are shown to be essential for the network's success.

  2. Self-organized global control of carbon emissions

    Science.gov (United States)

    Zhao, Zhenyuan; Fenn, Daniel J.; Hui, Pak Ming; Johnson, Neil F.

    2010-09-01

    There is much disagreement concerning how best to control global carbon emissions. We explore quantitatively how different control schemes affect the collective emission dynamics of a population of emitting entities. We uncover a complex trade-off which arises between average emissions (affecting the global climate), peak pollution levels (affecting citizens’ everyday health), industrial efficiency (affecting the nation’s economy), frequency of institutional intervention (affecting governmental costs), common information (affecting trading behavior) and market volatility (affecting financial stability). Our findings predict that a self-organized free-market approach at the level of a sector, state, country or continent can provide better control than a top-down regulated scheme in terms of market volatility and monthly pollution peaks. The control of volatility also has important implications for any future derivative carbon emissions market.

  3. Performance and energy efficiency in wireless self-organized networks

    Energy Technology Data Exchange (ETDEWEB)

    Gao, C.

    2009-07-01

    Self-organized packet radio networks (ad-hoc networks) and wireless sensor networks have got massive attention recently. One of critical problems in such networks is the energy efficiency, because wireless nodes are usually powered by battery. Energy efficiency design can dramatically increase the survivability and stability of wireless ad-hoc/sensor networks. In this thesis the energy efficiency has been considered at different protocol layers for wireless ad-hoc/sensor networks. The energy consumption of wireless nodes is inspected at the physical layer and MAC layer. At the network layer, some current routing protocols are compared and special attention has been paid to reactive routing protocols. A minimum hop analysis is given and according to the analysis result, a modification of AODV routing is proposed. A variation of transmit power can be also applied to clustering algorithm, which is believed to be able to control the scalability of network. Clustering a network can also improve the energy efficiency. We offer a clustering scheme based on the link state measurement and variation of transmit power of intra-cluster and inter-cluster transmission. Simulation shows that it can achieve both targets. In association with the clustering algorithm, a global synchronization scheme is proposed to increase the efficiency of clustering algorithm. The research attention has been also paid to self-organization for multi-hop cellular networks. A 2-hop 2-slot uplink proposal to infrastructure-based cellular networks. The proposed solution can significantly increase the throughput of uplink communication and reduce the energy consumption of wireless terminals. (orig.)

  4. Traffic instabilities in self-organized pedestrian crowds.

    Directory of Open Access Journals (Sweden)

    Mehdi Moussaïd

    Full Text Available In human crowds as well as in many animal societies, local interactions among individuals often give rise to self-organized collective organizations that offer functional benefits to the group. For instance, flows of pedestrians moving in opposite directions spontaneously segregate into lanes of uniform walking directions. This phenomenon is often referred to as a smart collective pattern, as it increases the traffic efficiency with no need of external control. However, the functional benefits of this emergent organization have never been experimentally measured, and the underlying behavioral mechanisms are poorly understood. In this work, we have studied this phenomenon under controlled laboratory conditions. We found that the traffic segregation exhibits structural instabilities characterized by the alternation of organized and disorganized states, where the lifetime of well-organized clusters of pedestrians follow a stretched exponential relaxation process. Further analysis show that the inter-pedestrian variability of comfortable walking speeds is a key variable at the origin of the observed traffic perturbations. We show that the collective benefit of the emerging pattern is maximized when all pedestrians walk at the average speed of the group. In practice, however, local interactions between slow- and fast-walking pedestrians trigger global breakdowns of organization, which reduce the collective and the individual payoff provided by the traffic segregation. This work is a step ahead toward the understanding of traffic self-organization in crowds, which turns out to be modulated by complex behavioral mechanisms that do not always maximize the group's benefits. The quantitative understanding of crowd behaviors opens the way for designing bottom-up management strategies bound to promote the emergence of efficient collective behaviors in crowds.

  5. Self-organized criticality revisited: non-local transport by turbulent amplification

    DEFF Research Database (Denmark)

    Milovanov, Alexander V.; Rasmussen, Jens Juul

    2015-01-01

    We revise the applications of self-organized criticality (SOC) as a paradigmatic model for tokamak plasma turbulence. The work, presented here, is built around the idea that some systems do not develop a pure critical state associable with SOC, since their dynamical evolution involves as a compet......We revise the applications of self-organized criticality (SOC) as a paradigmatic model for tokamak plasma turbulence. The work, presented here, is built around the idea that some systems do not develop a pure critical state associable with SOC, since their dynamical evolution involves...... as a competing key factor an inverse cascade of the energy in reciprocal space. Then relaxation of slowly increasing stresses will give rise to intermittent bursts of transport in real space and outstanding transport events beyond the range of applicability of the 'conventional' SOC. Also, we are concerned...... with the causes and origins of non-local transport in magnetized plasma, and show that this type of transport occurs naturally in self-consistent strong turbulence via a complexity coupling to the inverse cascade. We expect these coupling phenomena to occur in the parameter range of strong nonlinearity and time...

  6. Self-organized criticality in asymmetric exclusion model with noise for freeway traffic

    Science.gov (United States)

    Nagatani, Takashi

    1995-02-01

    The one-dimensional asymmetric simple-exclusion model with open boundaries for parallel update is extended to take into account temporary stopping of particles. The model presents the traffic flow on a highway with temporary deceleration of cars. Introducing temporary stopping into the asymmetric simple-exclusion model drives the system asymptotically into a steady state exhibiting a self-organized criticality. In the self-organized critical state, start-stop waves (or traffic jams) appear with various sizes (or lifetimes). The typical interval between consecutive jams scales as ≃ Lv with v = 0.51 ± 0.05 where L is the system size. It is shown that the cumulative jam-interval distribution Ns( L) satisfies the finite-size scaling form ( Ns( L) ≃ L- vf( s/ Lv). Also, the typical lifetime ≃ Lv‧ with v‧ = 0.52 ± 0.05. The cumulative distribution Nm( L) of lifetimes satisfies the finite-size scaling form Nm( L)≃ L-1g( m/ Lv‧).

  7. Perspectives of experimental and theoretical studies of self-organized dust structures in complex plasmas under microgravity conditions

    International Nuclear Information System (INIS)

    Tsytovich, V N

    2015-01-01

    We review research aimed at understanding the phenomena occurring in a complex plasma under microgravity conditions. Some aspects of the work already performed are considered that have not previously been given sufficient attention but which are potentially crucial for future work. These aspects, in particular, include the observation of compact dust structures that are estimated to be capable of confining all components of a dust plasma in a bounded spatial volume; experimental evidence of the nonlinear screening of dust particles; and experimental evidence of the excitation of collective electric fields. In theoretical terms, novel collective attraction processes between likely charged dust particles are discussed and all schemes of the shadowy attraction between dust particles used earlier, including in attempts to interpret observations, are reviewed and evaluated. Dust structures are considered from the standpoint of the current self-organization theory. It is emphasized that phase transitions between states of self-organized systems differ significantly from those in homogeneous states and that the phase diagrams should be constructed in terms of the parameters of a self-organized structure and cannot be constructed in terms of the temperature and density or similar parameters of homogeneous structures. Using the existing theoretical approaches to modeling self-organized structures in dust plasmas, the parameter distribution of a structure is recalculated for a simpler model that includes the quasineutrality condition and neglects diffusion. These calculations indicate that under microgravity conditions, any self-organized structure can contain a limited number of dust particles and is finite in size. The maximum possible number of particles in a structure determines the characteristic inter-grain distance in dust crystals that can be created under microgravity conditions. Crystallization criteria for the structures are examined and the quasispherical

  8. Influence of distance to urban markets on smallholder dairy farming systems in Kenya

    NARCIS (Netherlands)

    Migose, S.A.; Bebe, B.O.; Boer, de I.J.M.; Oosting, S.J.

    2018-01-01

    We studied influence of distance to urban markets on smallholder dairy farming system development. Farms were chosen from three locations that varied in distance to the urban market of Nakuru Town in the Kenyan highlands: urban location (UL, n = 10) at less than 15 km distance, mid-rural location

  9. Urban fuel demand in Ethiopia: an almost‐ideal demand system ...

    African Journals Online (AJOL)

    This paper investigates the opportunities for reducing the pressure of urban centers on rural forest areas, using a dataset of 350 urban households in Tigrai in northern Ethiopia. We applied an almost‐ideal demand system to fuels. The results suggest that reducing the pressure of urban centers on local forests cannot be ...

  10. A dispersion modelling system for urban air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Karppinen, A.; Kukkonen, J.; Nordlund, G.; Rantakrans, E.; Valkama, I.

    1998-10-01

    An Urban Dispersion Modelling system UDM-FMI, developed at the Finnish Meteorological Institute is described in the report. The modelling system includes a multiple source Gaussian plume model and a meteorological pre-processing model. The dispersion model is an integrated urban scale model, taking into account of all source categories (point, line, area and volume sources). It includes a treatment of chemical transformation (for NO{sub 2}) wet and dry deposition (for SO{sub 2}) plume rise, downwash phenomena and dispersion of inert particles. The model allows also for the influence of a finite mixing height. The model structure is mainly based on the state-of-the-art methodology. The system also computes statistical parameters from the time series, which can be compared to air quality guidelines. The relevant meteorological parameters for the dispersion model are evaluated using data produced by a meteorological pre-processor. The model is based mainly on the energy budget method. Results of national investigations have been used for evaluating climate-dependent parameters. The model utilises the synoptic meteorological observations, radiation records and aerological sounding observations. The model results include the hourly time series of the relevant atmospheric turbulence 51 refs.

  11. Managing urban energy system: A case of Suzhou in China

    International Nuclear Information System (INIS)

    Liang Sai; Zhang Tianzhu

    2011-01-01

    Managing urban energy system is vital for energy conservation and CO 2 reduction. Integrating energy input-output model with carbon emission pinch analysis, we propose a framework for managing urban energy system. This framework could analyze current energy demands and CO 2 emissions, predict their future possibilities and optimize energy mix of key sectors under CO 2 emission constraints. Key sectors are identified by the energy input-output table from both direct and accumulative perspectives. Moreover, taking Suzhou, a typical manufacturing center and export-oriented city in China, as a case example, energy metabolism of Suzhou in 2020 is predicted using energy input-output model. And three sectors named Coking, Smelting and pressing of metals and Production and supply of electric power are identified to have big effects on CO 2 emissions. Subsequently, energy mix of three identified key sectors is optimized under CO 2 emission constraints by the carbon emission pinch analysis. According to the results, clean energy sources will occupy a great position in Suzhou's future energy demands. And the reuse of wastes as energy sources should be limited to achieve CO 2 mitigation targets. Finally, policy implications of results and future work are discussed. - Research highlights: → We construct a framework for sustainable energy system management. → We apply the framework in a typical manufacturing center named Suzhou in China. → Key sectors for CO 2 emissions are identified, and energy mix is optimized. → Policy implications of results and future work are discussed.

  12. Self-organized nanostructures in silicon and glass for MEMS, MOEMS and BioMEMS

    International Nuclear Information System (INIS)

    Lilienthal, K.; Fischer, M.; Stubenrauch, M.; Schober, A.

    2010-01-01

    The utilization of self-organization in the process workflows for Micro-Electro-Mechanical-Systems (MEMS) and their derivatives is a smart way to get large areas of nanostructured surfaces for various applications. The generation of nano-masking spots by self-organizing residues in the plasma can lead to needle- or tube-like structures on the surface after (deep-) reactive ion etching. With lengths of 3 up to 25 μm and 150 up to 500 nm in diameter for silicon broad applications in the fields of micro fluidics with catalysts, micro-optical or mechanical mountings or carrier wafer bonding in microelectronics are possible. Now, we also developed dry etching processes for fused silica which shows analogue properties to 'Black Silicon' and investigated these glass nanostructures by a first parameter study to identify new usable structures and hybrids. This innovative starting point allows the transfer of 'Black Silicon' technologies and its applications to another important material class in micro- and nanotechnologies, fused silica.

  13. Lifelong learning of human actions with deep neural network self-organization.

    Science.gov (United States)

    Parisi, German I; Tani, Jun; Weber, Cornelius; Wermter, Stefan

    2017-12-01

    Lifelong learning is fundamental in autonomous robotics for the acquisition and fine-tuning of knowledge through experience. However, conventional deep neural models for action recognition from videos do not account for lifelong learning but rather learn a batch of training data with a predefined number of action classes and samples. Thus, there is the need to develop learning systems with the ability to incrementally process available perceptual cues and to adapt their responses over time. We propose a self-organizing neural architecture for incrementally learning to classify human actions from video sequences. The architecture comprises growing self-organizing networks equipped with recurrent neurons for processing time-varying patterns. We use a set of hierarchically arranged recurrent networks for the unsupervised learning of action representations with increasingly large spatiotemporal receptive fields. Lifelong learning is achieved in terms of prediction-driven neural dynamics in which the growth and the adaptation of the recurrent networks are driven by their capability to reconstruct temporally ordered input sequences. Experimental results on a classification task using two action benchmark datasets show that our model is competitive with state-of-the-art methods for batch learning also when a significant number of sample labels are missing or corrupted during training sessions. Additional experiments show the ability of our model to adapt to non-stationary input avoiding catastrophic interference. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. Self-organized control in cooperative robots using a pattern formation principle

    International Nuclear Information System (INIS)

    Starke, Jens; Ellsaesser, Carmen; Fukuda, Toshio

    2011-01-01

    Self-organized modular approaches proved in nature to be robust and optimal and are a promising strategy to control future concepts of flexible and modular manufacturing processes. We show how this can be applied to a model of flexible manufacturing based on time-dependent robot-target assignment problems where robot teams have to serve manufacturing targets such that an objective function is optimized. Feasibility of the self-organized solutions can be guaranteed even for unpredictable situations like sudden changes in the demands or breakdowns of robots. As example an uncrewed space mission is visualized in a simulation where robots build a space station. - Highlights: → Adapting a pattern formation principle to control cooperative robots in a robust way. → Flexible manufacturing systems are modelled by time-dependent assignment problems. → Coupled selection equations guarantee feasibility of solutions. → Solution structure (permutations) is not destroyed by inhomogeneous growth rates. → Example of an uncrewed space mission shows effectivity and robustness.

  15. Formation of self-organized anode patterns in arc discharge simulations

    International Nuclear Information System (INIS)

    Trelles, Juan Pablo

    2013-01-01

    Pattern formation and self-organization are phenomena commonly observed experimentally in diverse types of plasma systems, including atmospheric-pressure electric arc discharges. However, numerical simulations reproducing anode pattern formation in arc discharges have proven exceedingly elusive. Time-dependent three-dimensional thermodynamic non-equilibrium simulations reveal the spontaneous formation of self-organized patterns of anode attachment spots in the free-burning arc, a canonical thermal plasma flow established by a constant dc current between an axi-symmetric electrode configuration in the absence of external forcing. The number of spots, their size and distribution within the pattern depend on the applied total current and on the resolution of the spatial discretization, whereas the main properties of the plasma flow, such as maximum temperatures, velocity and voltage drop, depend only on the former. The sensibility of the solution to the spatial discretization stresses the computational requirements for comprehensive arc discharge simulations. The obtained anode patterns qualitatively agree with experimental observations and confirm that the spots originate at the fringes of the arc–anode attachment. The results imply that heavy-species–electron energy equilibration, in addition to thermal instability, has a dominant role in the formation of anode spots in arc discharges. (paper)

  16. Self-organized nanostructures in silicon and glass for MEMS, MOEMS and BioMEMS

    Energy Technology Data Exchange (ETDEWEB)

    Lilienthal, K., E-mail: katharina.lilienthal@tu-ilmenau.de [Research Group ' Micro fluidics and Biosensors' , Ilmenau University of Technology, Institute of Micro- and Nanotechnologies, D-98693 Ilmenau (Germany); Fischer, M. [Research Group ' Micro fluidics and Biosensors' , Ilmenau University of Technology, Institute of Micro- and Nanotechnologies, D-98693 Ilmenau (Germany); Stubenrauch, M. [Department of Micromechanical Systems, Ilmenau University of Technology, Institute of Micro- and Nanotechnologies, D-98693 Ilmenau (Germany); Schober, A. [Research Group ' Micro fluidics and Biosensors' , Ilmenau University of Technology, Institute of Micro- and Nanotechnologies, D-98693 Ilmenau (Germany)

    2010-05-25

    The utilization of self-organization in the process workflows for Micro-Electro-Mechanical-Systems (MEMS) and their derivatives is a smart way to get large areas of nanostructured surfaces for various applications. The generation of nano-masking spots by self-organizing residues in the plasma can lead to needle- or tube-like structures on the surface after (deep-) reactive ion etching. With lengths of 3 up to 25 {mu}m and 150 up to 500 nm in diameter for silicon broad applications in the fields of micro fluidics with catalysts, micro-optical or mechanical mountings or carrier wafer bonding in microelectronics are possible. Now, we also developed dry etching processes for fused silica which shows analogue properties to 'Black Silicon' and investigated these glass nanostructures by a first parameter study to identify new usable structures and hybrids. This innovative starting point allows the transfer of 'Black Silicon' technologies and its applications to another important material class in micro- and nanotechnologies, fused silica.

  17. Self-organized amniogenesis by human pluripotent stem cells in a biomimetic implantation-like niche

    Science.gov (United States)

    Shao, Yue; Taniguchi, Kenichiro; Gurdziel, Katherine; Townshend, Ryan F.; Xue, Xufeng; Yong, Koh Meng Aw; Sang, Jianming; Spence, Jason R.; Gumucio, Deborah L.; Fu, Jianping

    2017-04-01

    Amniogenesis--the development of amnion--is a critical developmental milestone for early human embryogenesis and successful pregnancy. However, human amniogenesis is poorly understood due to limited accessibility to peri-implantation embryos and a lack of in vitro models. Here we report an efficient biomaterial system to generate human amnion-like tissue in vitro through self-organized development of human pluripotent stem cells (hPSCs) in a bioengineered niche mimicking the in vivo implantation environment. We show that biophysical niche factors act as a switch to toggle hPSC self-renewal versus amniogenesis under self-renewal-permissive biochemical conditions. We identify a unique molecular signature of hPSC-derived amnion-like cells and show that endogenously activated BMP-SMAD signalling is required for the amnion-like tissue development by hPSCs. This study unveils the self-organizing and mechanosensitive nature of human amniogenesis and establishes the first hPSC-based model for investigating peri-implantation human amnion development, thereby helping advance human embryology and reproductive medicine.

  18. A principle of fractal-stochastic dualism and Gompertzian dynamics of growth and self-organization.

    Science.gov (United States)

    Waliszewski, Przemyslaw

    2005-10-01

    The emergence of Gompertzian dynamics at the macroscopic, tissue level during growth and self-organization is determined by the existence of fractal-stochastic dualism at the microscopic level of supramolecular, cellular system. On one hand, Gompertzian dynamics results from the complex coupling of at least two antagonistic, stochastic processes at the molecular cellular level. It is shown that the Gompertz function is a probability function, its derivative is a probability density function, and the Gompertzian distribution of probability is of non-Gaussian type. On the other hand, the Gompertz function is a contraction mapping and defines fractal dynamics in time-space; a prerequisite condition for the coupling of processes. Furthermore, the Gompertz function is a solution of the operator differential equation with the Morse-like anharmonic potential. This relationship indicates that distribution of intrasystemic forces is both non-linear and asymmetric. The anharmonic potential is a measure of the intrasystemic interactions. It attains a point of the minimum (U(0), t(0)) along with a change of both complexity and connectivity during growth and self-organization. It can also be modified by certain factors, such as retinoids.

  19. Self-organized dynamics in local load-sharing fiber bundle models.

    Science.gov (United States)

    Biswas, Soumyajyoti; Chakrabarti, Bikas K

    2013-10-01

    We study the dynamics of a local load-sharing fiber bundle model in two dimensions under an external load (which increases with time at a fixed slow rate) applied at a single point. Due to the local load-sharing nature, the redistributed load remains localized along the boundary of the broken patch. The system then goes to a self-organized state with a stationary average value of load per fiber along the (increasing) boundary of the broken patch (damaged region) and a scale-free distribution of avalanche sizes and other related quantities are observed. In particular, when the load redistribution is only among nearest surviving fiber(s), the numerical estimates of the exponent values are comparable with those of the Manna model. When the load redistribution is uniform along the patch boundary, the model shows a simple mean-field limit of this self-organizing critical behavior, for which we give analytical estimates of the saturation load per fiber values and avalanche size distribution exponent. These are in good agreement with numerical simulation results.

  20. Manifold Learning with Self-Organizing Mapping for Feature Extraction of Nonlinear Faults in Rotating Machinery

    Directory of Open Access Journals (Sweden)

    Lin Liang

    2015-01-01

    Full Text Available A new method for extracting the low-dimensional feature automatically with self-organization mapping manifold is proposed for the detection of rotating mechanical nonlinear faults (such as rubbing, pedestal looseness. Under the phase space reconstructed by single vibration signal, the self-organization mapping (SOM with expectation maximization iteration algorithm is used to divide the local neighborhoods adaptively without manual intervention. After that, the local tangent space alignment algorithm is adopted to compress the high-dimensional phase space into low-dimensional feature space. The proposed method takes advantages of the manifold learning in low-dimensional feature extraction and adaptive neighborhood construction of SOM and can extract intrinsic fault features of interest in two dimensional projection space. To evaluate the performance of the proposed method, the Lorenz system was simulated and rotation machinery with nonlinear faults was obtained for test purposes. Compared with the holospectrum approaches, the results reveal that the proposed method is superior in identifying faults and effective for rotating machinery condition monitoring.

  1. Applications of geographic information system and expert system for urban runoff and water quality management

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Beum-Hee [Pai Chai University, Taejeon(Korea)

    2001-06-30

    It is very important to select appropriate methods of collecting, predicting, and analyzing information for the development of urban water resources and the prevention of disasters. Thus, in this study an accurate data generation method is developed using Geographic Information System (GIS) and Remote Sensing (RS). The methods of development and application of an expert system are suggested to solve more efficiently the problems of water resources and quality induced by the rapid urbanization. The time-varying data in a large region, the An-Yang Cheon watershed, were reasonably obtained by the application of the GIS using ARC/INFO and RS data. The ESPE (Expert System for Parameter Estimation), an expert system is developed using the CLIPS 6.0. The simulated results showed agreement with the measured data globally. These methods are expected to efficiently simulate the runoff and water quality in the rapidly varying urban area. (author). 10 refs., 4 tabs., 10 figs.

  2. Sustainability, resilience and governance of an urban food system: a case study of peri-urban Wuhan

    OpenAIRE

    Dolley, Jonathan

    2017-01-01

    While it is clear that urban food systems need to be made resilient so that broader sustainability\\ud goals can be maintained over time, it has been a matter of debate as to how resilience should be\\ud conceptualised when applied to social-ecological systems. Through a case study of peri-urban\\ud Wuhan, this research develops and applies a resilience based conceptual framework for periurban\\ud food systems analysis in order to explore the potential for an enhanced understanding of\\ud resilien...

  3. Phosphorus cycling in Montreal's food and urban agriculture systems.

    Science.gov (United States)

    Metson, Geneviève S; Bennett, Elena M

    2015-01-01

    Cities are a key system in anthropogenic phosphorus (P) cycling because they concentrate both P demand and waste production. Urban agriculture (UA) has been proposed as a means to improve P management by recycling cities' P-rich waste back into local food production. However, we have a limited understanding of the role UA currently plays in the P cycle of cities or its potential to recycle local P waste. Using existing data combined with surveys of local UA practitioners, we quantified the role of UA in the P cycle of Montreal, Canada to explore the potential for UA to recycle local P waste. We also used existing data to complete a substance flow analysis of P flows in the overall food system of Montreal. In 2012, Montreal imported 3.5 Gg of P in food, of which 2.63 Gg ultimately accumulated in landfills, 0.36 Gg were discharged to local waters, and only 0.09 Gg were recycled through composting. We found that UA is only a small sub-system in the overall P cycle of the city, contributing just 0.44% of the P consumed as food in the city. However, within the UA system, the rate of recycling is high: 73% of inputs applied to soil were from recycled sources. While a Quebec mandate to recycle 100% of all organic waste by 2020 might increase the role of UA in P recycling, the area of land in UA is too small to accommodate all P waste produced on the island. UA may, however, be a valuable pathway to improve urban P sustainability by acting as an activity that changes residents' relationship to, and understanding of, the food system and increases their acceptance of composting.

  4. Self-organized criticality as a paradigm for transport processes in magnetically confined plasma

    International Nuclear Information System (INIS)

    Karreras, B.A.; N'yuman, D.; Linch, V.E.

    1996-01-01

    Many models of natural events prove the basic hypotheses of self-organized critically. The concept on self-organized criticality combines self similarity on a spatial and time scale, characteristic of many such events. Application of the self-organized criticality concept to plasma dynamics close to the stability limit opens new possibilities for comprehension of such events as the Bom scaling, profile selfconsistency, wide band fluctuation spectra with universal characteristics and small time scales. Refs. 51, figs. 17

  5. Self-Organization of Template-Replicating Polymers and the Spontaneous Rise of Genetic Information

    Directory of Open Access Journals (Sweden)

    Jarle Breivik

    2001-11-01

    Full Text Available Abstract: Living systems imply self-reproducing constructs capable of Darwinian evolution. How such dynamics can arise from undirected interactions between simple monomeric objects remains an open question. Here we circumvent difficulties related to the manipulation of chemical interactions, and present a system of ferromagnetic objects that self-organize into template-replicating polymers due to environmental fluctuations in temperature. Initially random sequences of monomers direct the formation of complementary sequences, and structural information is inherited from one structure to another. Selective replication of sequences occurs in dynamic interaction with the environment, and the system demonstrates the fundamental link between thermodynamics, information theory, and life science in an unprecedented manner.

  6. The Topological Analysis of Urban Transit System as a Small-World Network

    OpenAIRE

    Zhaosheng Yang; Huxing Zhou; Peng Gao; Hong Chen; Nan Zhang

    2011-01-01

    This paper proposes a topological analysis of urban transit system based on a functional representation network constructed from the urban transit system in Beijing. The representation gives a functional view on nodes named a transit line. Statistical measures are computed and introduced in complex network analysis. It shows that the urban transit system forms small-world networks and exhibits properties different from random networks and regular networks. Furthermore, the topological propert...

  7. Effects of rainwater harvesting on centralized urban water supply systems

    DEFF Research Database (Denmark)

    Grandet, C.; Binning, Philip John; Mikkelsen, Peter Steen

    2010-01-01

    depths but very different temporal distributions. Supply reliability and the extent of reliance on the public distribution system are identified as suitable performance indicators for mains water infrastructure. A uniform temporal distribution of rainfall in an oceanic climate like that of Dinard......, Northern France, yielded supply reliabilities close to 100% for reasonable tank sizes (0.065 m3/m2 of roof area in Dinard compared with 0.262 m3/m2 in Nice with a RWSO of 30% for a detached house). However, the collection and use of rainfall results in a permanent decrease in mains water demand leading...... to an increase in water age in the distribution network. Investigations carried on a real network showed that water age is greatly affected when rainwater supplies more than 30% of the overall water demand. In urban water utilities planning, rainwater supply systems may however be profitable for the community...

  8. Urbanism, climate change and health: systems approaches to governance.

    Science.gov (United States)

    Capon, Anthony G; Synnott, Emma S; Holliday, Sue

    2009-01-01

    Effective action on climate change health impacts and vulnerability will require systems approaches and integrated policy and planning responses from a range of government agencies. Similar responses are needed to address other complex problems, such as the obesity epidemic. Local government, with its focus on the governance of place, will have a key role in responding to these convergent agendas. Industry can also be part of the solution - indeed it must be, because it has a lead role in relevant sectors. Understanding the co-benefits for health of climate mitigation actions will strengthen the case for early action. There is a need for improved decision support tools to inform urban governance. These tools should be based on a systems approach and should incorporate a spatial perspective.

  9. Evolving Self-Organized Behavior for Homogeneous and Heterogeneous UAV or UCAV Swarms

    National Research Council Canada - National Science Library

    Price, Ian C

    2006-01-01

    This investigation uses a self-organization (SO) approach to enable cooperative search and destruction of retaliating targets with swarms of homogeneous and heterogeneous unmanned aerial vehicles (UAVs...

  10. System-wide Benchmark Simulation Model for integrated analysis of urban wastewater systems

    DEFF Research Database (Denmark)

    Saagi, R.; Flores-Alsina, X.; Gernaey, K. V.

    Interactions between different components (sewer, wastewater treatment plant (WWTP) and river) of an urban wastewater system (UWS) are widely recognized (Benedetti et al., 2013). This has resulted in an increasing interest in the modelling of the UWS. System-wide models take into account the inte...

  11. Electronic self-organization in layered transition metal dichalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Ritschel, Tobias

    2015-10-30

    The interplay between different self-organized electronically ordered states and their relation to unconventional electronic properties like superconductivity constitutes one of the most exciting challenges of modern condensed matter physics. In the present thesis this issue is thoroughly investigated for the prototypical layered material 1T-TaS{sub 2} both experimentally and theoretically. At first the static charge density wave order in 1T-TaS{sub 2} is investigated as a function of pressure and temperature by means of X-ray diffraction. These data indeed reveal that the superconductivity in this material coexists with an inhomogeneous charge density wave on a macroscopic scale in real space. This result is fundamentally different from a previously proposed separation of superconducting and insulating regions in real space. Furthermore, the X-ray diffraction data uncover the important role of interlayer correlations in 1T-TaS{sub 2}. Based on the detailed insights into the charge density wave structure obtained by the X-ray diffraction experiments, density functional theory models are deduced in order to describe the electronic structure of 1T-TaS{sub 2} in the second part of this thesis. As opposed to most previous studies, these calculations take the three-dimensional character of the charge density wave into account. Indeed the electronic structure calculations uncover complex orbital textures, which are interwoven with the charge density wave order and cause dramatic differences in the electronic structure depending on the alignment of the orbitals between neighboring layers. Furthermore, it is demonstrated that these orbital-mediated effects provide a route to drive semiconductor-to-metal transitions with technologically pertinent gaps and on ultrafast timescales. These results are particularly relevant for the ongoing development of novel, miniaturized and ultrafast devices based on layered transition metal dichalcogenides. The discovery of orbital textures

  12. Contamination of Detained Sediment in Sustainable Urban Drainage Systems

    Directory of Open Access Journals (Sweden)

    Deonie Allen

    2017-05-01

    Full Text Available Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS. The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix.

  13. Fractal analysis of urban environment: land use and sewer system

    Science.gov (United States)

    Gires, A.; Ochoa Rodriguez, S.; Van Assel, J.; Bruni, G.; Murla Tulys, D.; Wang, L.; Pina, R.; Richard, J.; Ichiba, A.; Willems, P.; Tchiguirinskaia, I.; ten Veldhuis, M. C.; Schertzer, D. J. M.

    2014-12-01

    Land use distribution are usually obtained by automatic processing of satellite and airborne pictures. The complexity of the obtained patterns which are furthermore scale dependent is enhanced in urban environment. This scale dependency is even more visible in a rasterized representation where only a unique class is affected to each pixel. A parameter commonly analysed in urban hydrology is the coefficient of imperviousness, which reflects the proportion of rainfall that will be immediately active in the catchment response. This coefficient is strongly scale dependent with a rasterized representation. This complex behaviour is well grasped with the help of the scale invariant notion of fractal dimension which enables to quantify the space occupied by a geometrical set (here the impervious areas) not only at a single scale but across all scales. This fractal dimension is also compared to the ones computed on the representation of the catchments with the help of operational semi-distributed models. Fractal dimensions of the corresponding sewer systems are also computed and compared with values found in the literature for natural river networks. This methodology is tested on 7 pilot sites of the European NWE Interreg IV RainGain project located in France, Belgium, Netherlands, United-Kingdom and Portugal. Results are compared between all the case study which exhibit different physical features (slope, level of urbanisation, population density...).

  14. Daily urban systems in function of the spatial organisation in Serbia

    Directory of Open Access Journals (Sweden)

    Tošić Dragutin

    2009-01-01

    Full Text Available In the form of theoretical discussion, this paper makes a brief analysis of relevant methodological steps for determination of Daily Urban Systems and the approach for their spatial-functional representation. The potential of using Daily Urban Systems as instruments for regional planning and regional development has been indicated. A model for determining Daily Urban Systems in Serbia has been proposed according to our socio-economic conditions. The experience thus far in reference to research of demographic, spatial and functional components of Daily Urban Systems demonstrates that for definition of their spatial and temporal manifestation and continuity models, the most relevant indicators are those which relate to distribution and functional specialization of work centers and places of living, and those which relate to quantitative-qualitative characteristics of daily migrants. Daily Urban Systems of Serbia have been developed under the conditions of continuous redistribution of population from rural to urban settlements and more or less synchronized processes of deagrarisation, deindustrialisation and urbanization with general socioeconomic flows. According to the dynamics of development in functions of work, living, education, service activities and public-social facilities in the urban regions, there have been formed Daily Urban Systems with appropriate hierarchy. The paper presents results of the latest research of Daily Urban Systems in Serbia, driven by scientific and appreciative reasons (preparation of the Regional spatial plans for municipalities of Južno pomoravlje and for Timočka krajina, and determination of the nodal systems in Zlatibor county. Daily Urban Systems, especially their regional role and implication, are proposed for instruments of rational spatial-functional organization of Serbia. According to the relevant theoretical-methodological approach and presented empirical evidence, the model of Daily Urban Systems

  15. A model library for simulation and benchmarking of integrated urban wastewater systems

    DEFF Research Database (Denmark)

    Saagi, R.; Flores Alsina, Xavier; Kroll, J. S.

    2017-01-01

    This paper presents a freely distributed, open-source toolbox to predict the behaviour of urban wastewater systems (UWS). The proposed library is used to develop a system-wide Benchmark Simulation Model (BSM-UWS) for evaluating (local/global) control strategies in urban wastewater systems (UWS...

  16. Holistic Analysis of the Urban Water Systems in Greater Cincinnati Region

    Science.gov (United States)

    Urban water and wastewater systems with two utilities in Greater Cincinnati region were evaluated as a case study to elucidates a bigger picture of a typical centralized urban water system. Two different integrated assessment metrics were used to analyze the same system. LCA an...

  17. Self-Organizing Maps on the Cell Broadband Engine Architecture

    International Nuclear Information System (INIS)

    McConnell, Sabine M

    2010-01-01

    We present and evaluate novel parallel implementations of Self-Organizing Maps for the Cell Broadband Engine Architecture. Motivated by the interactive nature of the data-mining process, we evaluate the scalability of the implementations on two clusters using different network characteristics and incarnations (PS3 TM console and PowerXCell 8i) of the architecture. Our implementations use varying combinations of the Power Processing Elements (PPEs) and Synergistic Processing Elements (SPEs) found in the Cell architecture. For a single processor, our implementation scaled well with the number of SPEs regardless of the incarnation. When combining multiple PS3 TM consoles, the synchronization over the slower network resulted in poor speedups and demonstrated that the use of such a low-cost cluster may be severely restricted, even without the use of SPEs. When using multiple SPEs for the PowerXCell 8i cluster, the speedup grew linearly with increasing number of SPEs for a given number of processors, and linear up to a maximum with the number of processors for a given number of SPEs. Our implementation achieved a worst-case efficiency of 67% for the maximum number of processing elements involved in the computation, but consistently higher values for smaller numbers of processing elements with speedups of up to 70.

  18. Self-organization of human embryonic stem cells on micropatterns

    Science.gov (United States)

    Deglincerti, Alessia; Etoc, Fred; Guerra, M. Cecilia; Martyn, Iain; Metzger, Jakob; Ruzo, Albert; Simunovic, Mijo; Yoney, Anna; Brivanlou, Ali H.; Siggia, Eric; Warmflash, Aryeh

    2018-01-01

    Fate allocation in the gastrulating embryo is spatially organized as cells differentiate to specialized cell types depending on their positions with respect to the body axes. There is a need for in vitro protocols that allow the study of spatial organization associated with this developmental transition. While embryoid bodies and organoids can exhibit some spatial organization of differentiated cells, these methods do not yield consistent and fully reproducible results. Here, we describe a micropatterning approach where human embryonic stem cells are confined to disk-shaped, sub-millimeter colonies. After 42 hours of BMP4 stimulation, cells form self-organized differentiation patterns in concentric radial domains, which express specific markers associated with the embryonic germ layers, reminiscent of gastrulating embryos. Our protocol takes 3 days; it uses commercial microfabricated slides (CYTOO), human laminin-521 (LN-521) as extra-cellular matrix coating, and either conditioned or chemically-defined medium (mTeSR). Differentiation patterns within individual colonies can be determined by immunofluorescence and analyzed with cellular resolution. Both the size of the micropattern and the type of medium affect the patterning outcome. The protocol is appropriate for personnel with basic stem cell culture training. This protocol describes a robust platform for quantitative analysis of the mechanisms associated with pattern formation at the onset of gastrulation. PMID:27735934

  19. Trading leads to scale-free self-organization

    Science.gov (United States)

    Ebert, M.; Paul, W.

    2012-12-01

    Financial markets display scale-free behavior in many different aspects. The power-law behavior of part of the distribution of individual wealth has been recognized by Pareto as early as the nineteenth century. Heavy-tailed and scale-free behavior of the distribution of returns of different financial assets have been confirmed in a series of works. The existence of a Pareto-like distribution of the wealth of market participants has been connected with the scale-free distribution of trading volumes and price-returns. The origin of the Pareto-like wealth distribution, however, remained obscure. Here we show that in a market where the imbalance of supply and demand determines the direction of prize changes, it is the process of trading itself that spontaneously leads to a self-organization of the market with a Pareto-like wealth distribution for the market participants and at the same time to a scale-free behavior of return fluctuations and trading volume distributions.

  20. Self-organization of punishment in structured populations

    Science.gov (United States)

    Perc, Matjaž; Szolnoki, Attila

    2012-04-01

    Cooperation is crucial for the remarkable evolutionary success of the human species. Not surprisingly, some individuals are willing to bear additional costs in order to punish defectors. Current models assume that, once set, the fine and cost of punishment do not change over time. Here we show that relaxing this assumption by allowing players to adapt their sanctioning efforts in dependence on the success of cooperation can explain both the spontaneous emergence of punishment and its ability to deter defectors and those unwilling to punish them with globally negligible investments. By means of phase diagrams and the analysis of emerging spatial patterns, we demonstrate that adaptive punishment promotes public cooperation through the invigoration of spatial reciprocity, the prevention of the emergence of cyclic dominance, or the provision of competitive advantages to those that sanction antisocial behavior. The results presented indicate that the process of self-organization significantly elevates the effectiveness of punishment, and they reveal new mechanisms by means of which this fascinating and widespread social behavior could have evolved.

  1. Mobile Anomaly Detection Based on Improved Self-Organizing Maps

    Directory of Open Access Journals (Sweden)

    Chunyong Yin

    2017-01-01

    Full Text Available Anomaly detection has always been the focus of researchers and especially, the developments of mobile devices raise new challenges of anomaly detection. For example, mobile devices can keep connection with Internet and they are rarely turned off even at night. This means mobile devices can attack nodes or be attacked at night without being perceived by users and they have different characteristics from Internet behaviors. The introduction of data mining has made leaps forward in this field. Self-organizing maps, one of famous clustering algorithms, are affected by initial weight vectors and the clustering result is unstable. The optimal method of selecting initial clustering centers is transplanted from K-means to SOM. To evaluate the performance of improved SOM, we utilize diverse datasets and KDD Cup99 dataset to compare it with traditional one. The experimental results show that improved SOM can get higher accuracy rate for universal datasets. As for KDD Cup99 dataset, it achieves higher recall rate and precision rate.

  2. Surface self-organization in multilayer film coatings

    Science.gov (United States)

    Shuvalov, Gleb M.; Kostyrko, Sergey A.

    2017-12-01

    It is a recognized fact that during film deposition and subsequent thermal processing the film surface evolves into an undulating profile. Surface roughness affects many important aspects in the engineering application of thin film materials such as wetting, heat transfer, mechanical, electromagnetic and optical properties. To accurately control the morphological surface modifications at the micro- and nanoscale and improve manufacturing techniques, we design a mathematical model of the surface self-organization process in multilayer film materials. In this paper, we consider a solid film coating with an arbitrary number of layers under plane strain conditions. The film surface has a small initial perturbation described by a periodic function. It is assumed that the evolution of the surface relief is governed by surface and volume diffusion. Based on Gibbs thermodynamics and linear theory of elasticity, we present a procedure for constructing a governing equation that gives the amplitude change of the surface perturbation with time. A parametric study of the evolution equation leads to the definition of a critical undulation wavelength that stabilizes the surface. As a numerical result, the influence of geometrical and physical parameters on the morphological stability of an isotropic two-layered film coating is analyzed.

  3. Business Client Segmentation in Banking Using Self-Organizing Maps

    Directory of Open Access Journals (Sweden)

    Bach Mirjana Pejić

    2014-11-01

    Full Text Available Segmentation in banking for the business client market is traditionally based on size measured in terms of income and the number of employees, and on statistical clustering methods (e.g. hierarchical clustering, k-means. The goal of the paper is to demonstrate that self-organizing maps (SOM effectively extend the pool of possible criteria for segmentation of the business client market with more relevant criteria, including behavioral, demographic, personal, operational, situational, and cross-selling products. In order to attain the goal of the paper, the dataset on business clients of several banks in Croatia, which, besides size, incorporates a number of different criteria, is analyzed using the SOM-Ward clustering algorithm of Viscovery SOMine software. The SOM-Ward algorithm extracted three segments that differ with respect to the attributes of foreign trade operations (import/export, annual income, origin of capital, important bank selection criteria, views on the loan selection and the industry. The analyzed segments can be used by banks for deciding on the direction of further marketing activities.

  4. Self-Organized Criticality in an Anisotropic Earthquake Model

    Science.gov (United States)

    Li, Bin-Quan; Wang, Sheng-Jun

    2018-03-01

    We have made an extensive numerical study of a modified model proposed by Olami, Feder, and Christensen to describe earthquake behavior. Two situations were considered in this paper. One situation is that the energy of the unstable site is redistributed to its nearest neighbors randomly not averagely and keeps itself to zero. The other situation is that the energy of the unstable site is redistributed to its nearest neighbors randomly and keeps some energy for itself instead of reset to zero. Different boundary conditions were considered as well. By analyzing the distribution of earthquake sizes, we found that self-organized criticality can be excited only in the conservative case or the approximate conservative case in the above situations. Some evidence indicated that the critical exponent of both above situations and the original OFC model tend to the same result in the conservative case. The only difference is that the avalanche size in the original model is bigger. This result may be closer to the real world, after all, every crust plate size is different. Supported by National Natural Science Foundation of China under Grant Nos. 11675096 and 11305098, the Fundamental Research Funds for the Central Universities under Grant No. GK201702001, FPALAB-SNNU under Grant No. 16QNGG007, and Interdisciplinary Incubation Project of SNU under Grant No. 5

  5. Self-organization of social hierarchy on interaction networks

    International Nuclear Information System (INIS)

    Fujie, Ryo; Odagaki, Takashi

    2011-01-01

    In order to examine the effects of interaction network structures on the self-organization of social hierarchy, we introduce the agent-based model: each individual as on a node of a network has its own power and its internal state changes by fighting with its neighbors and relaxation. We adopt three different networks: regular lattice, small-world network and scale-free network. For the regular lattice, we find the emergence of classes distinguished by the internal state. The transition points where each class emerges are determined analytically, and we show that each class is characterized by the local ranking relative to their neighbors. We also find that the antiferromagnetic-like configuration emerges just above the critical point. For the heterogeneous networks, individuals become winners (or losers) in descending order of the number of their links. By using mean-field analysis, we reveal that the transition point is determined by the maximum degree and the degree distribution in its neighbors

  6. LSOT: A Lightweight Self-Organized Trust Model in VANETs

    Directory of Open Access Journals (Sweden)

    Zhiquan Liu

    2016-01-01

    Full Text Available With the advances in automobile industry and wireless communication technology, Vehicular Ad hoc Networks (VANETs have attracted the attention of a large number of researchers. Trust management plays an important role in VANETs. However, it is still at the preliminary stage and the existing trust models cannot entirely conform to the characteristics of VANETs. This work proposes a novel Lightweight Self-Organized Trust (LSOT model which contains trust certificate-based and recommendation-based trust evaluations. Both the supernodes and trusted third parties are not needed in our model. In addition, we comprehensively consider three factor weights to ease the collusion attack in trust certificate-based trust evaluation, and we utilize the testing interaction method to build and maintain the trust network and propose a maximum local trust (MLT algorithm to identify trustworthy recommenders in recommendation-based trust evaluation. Furthermore, a fully distributed VANET scenario is deployed based on the famous Advogato dataset and a series of simulations and analysis are conducted. The results illustrate that our LSOT model significantly outperforms the excellent experience-based trust (EBT and Lightweight Cross-domain Trust (LCT models in terms of evaluation performance and robustness against the collusion attack.

  7. Self-organization of muscle cell structure and function.

    Directory of Open Access Journals (Sweden)

    Anna Grosberg

    2011-02-01

    Full Text Available The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

  8. Self-organization of muscle cell structure and function.

    Science.gov (United States)

    Grosberg, Anna; Kuo, Po-Ling; Guo, Chin-Lin; Geisse, Nicholas A; Bray, Mark-Anthony; Adams, William J; Sheehy, Sean P; Parker, Kevin Kit

    2011-02-01

    The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

  9. Benefits of Self-Organizing Networks (SON for Mobile Operators

    Directory of Open Access Journals (Sweden)

    Olav Østerbø

    2012-01-01

    Full Text Available Self-Organizing Networks (SON is a collection of functions for automatic configuration, optimization, diagnostisation and healing of cellular networks. It is considered to be a necessity in future mobile networks and operations due to the increased cost pressure. The main drivers are essentially to reduce CAPEX and OPEX, which would otherwise increase dramatically due to increased number of network parameters that has to be monitored and set, the rapidly increasing numbers of base stations in the network and parallel operation of 2G, 3G and Evolved Packet Core (EPC infrastructures. This paper presents evaluations on the use of some of the most important SON components. Mobile networks are getting more complex to configure, optimize and maintain. Many SON functions will give cost savings and performance benefits from the very beginning of a network deployment and these should be prioritized now. But even if many functions are already available and can give large benefits, the field is still in its infancy and more advanced functions are either not yet implemented or have immature implementations. It is therefore necessary to have a strategy for how and when different SON functions should be introduced in mobile networks.

  10. Random-Access Technique for Self-Organization of 5G Millimeter-Wave Cellular Communications

    Directory of Open Access Journals (Sweden)

    Jasper Meynard Arana

    2016-01-01

    Full Text Available The random-access (RA technique is a key procedure in cellular networks and self-organizing networks (SONs, but the overall processing time of this technique in millimeter-wave (mm-wave cellular systems with directional beams is very long because RA preambles (RAPs should be transmitted in all directions of Tx and Rx beams. In this paper, two different types of preambles (RAP-1 and RAP-2 are proposed to reduce the processing time in the RA stage. After analyzing the correlation property, false-alarm probability, and detection probability of the proposed RAPs, we perform simulations to show that the RAP-2 is suitable for RA in mm-wave cellular systems with directional beams because of the smaller processing time and high detection probability in multiuser environments.

  11. FPGA implementation of self organizing map with digital phase locked loops.

    Science.gov (United States)

    Hikawa, Hiroomi

    2005-01-01

    The self-organizing map (SOM) has found applicability in a wide range of application areas. Recently new SOM hardware with phase modulated pulse signal and digital phase-locked loops (DPLLs) has been proposed (Hikawa, 2005). The system uses the DPLL as a computing element since the operation of the DPLL is very similar to that of SOM's computation. The system also uses square waveform phase to hold the value of the each input vector element. This paper discuss the hardware implementation of the DPLL SOM architecture. For effective hardware implementation, some components are redesigned to reduce the circuit size. The proposed SOM architecture is described in VHDL and implemented on field programmable gate array (FPGA). Its feasibility is verified by experiments. Results show that the proposed SOM implemented on the FPGA has a good quantization capability, and its circuit size very small.

  12. Predicting spiral wave patterns from cell properties in a model of biological self-organization.

    Science.gov (United States)

    Geberth, Daniel; Hütt, Marc-Thorsten

    2008-09-01

    In many biological systems, biological variability (i.e., systematic differences between the system components) can be expected to outrank statistical fluctuations in the shaping of self-organized patterns. In principle, the distribution of single-element properties should thus allow predicting features of such patterns. For a mathematical model of a paradigmatic and well-studied pattern formation process, spiral waves of cAMP signaling in colonies of the slime mold Dictyostelium discoideum, we explore this possibility and observe a pronounced anticorrelation between spiral waves and cell properties (namely, the firing rate) and particularly a clustering of spiral wave tips in regions devoid of spontaneously firing (pacemaker) cells. Furthermore, we observe local inhomogeneities in the distribution of spiral chiralities, again induced by the pacemaker distribution. We show that these findings can be explained by a simple geometrical model of spiral wave generation.

  13. An autoregulatory circuit for long-range self-organization in Dictyostelium cell populations.

    Science.gov (United States)

    Sawai, Satoshi; Thomason, Peter A; Cox, Edward C

    2005-01-20

    Nutrient-deprived Dictyostelium amoebae aggregate to form a multicellular structure by chemotaxis, moving towards propagating waves of cyclic AMP that are relayed from cell to cell. Organizing centres are not formed by founder cells, but are dynamic entities consisting of cores of outwardly rotating spiral waves that self-organize in a homogeneous cell population. Spiral waves are ubiquitously observed in chemical reactions as well as in biological systems. Although feedback control of spiral waves in spatially extended chemical reactions has been demonstrated in recent years, the mechanism by which control is achieved in living systems is unknown. Here we show that mutants of the cyclic AMP/protein kinase A pathway show periodic signalling, but fail to organize coherent long-range wave territories, owing to the appearance of numerous spiral cores. A theoretical model suggests that autoregulation of cell excitability mediated by protein kinase A acts to optimize the number of signalling centres.

  14. Implementation of self-organizing neural networks for visuo-motor control of an industrial robot.

    Science.gov (United States)

    Walter, J A; Schulten, K I

    1993-01-01

    The implementation of two neural network algorithms for visuo-motor control of an industrial robot (Puma 562) is reported. The first algorithm uses a vector quantization technique, the ;neural-gas' network, together with an error correction scheme based on a Widrow-Hoff-type learning rule. The second algorithm employs an extended self-organizing feature map algorithm. Based on visual information provided by two cameras, the robot learns to position its end effector without an external teacher. Within only 3000 training steps, the robot-camera system is capable of reducing the positioning error of the robot's end effector to approximately 0.1% of the linear dimension of the work space. By employing adaptive feedback the robot succeeds in compensating not only slow calibration drifts, but also sudden changes in its geometry. Hardware aspects of the robot-camera system are discussed.

  15. Identification-based chaos control via backstepping design using self-organizing fuzzy neural networks

    International Nuclear Information System (INIS)

    Peng Yafu; Hsu, C.-F.

    2009-01-01

    This paper proposes an identification-based adaptive backstepping control (IABC) for the chaotic systems. The IABC system is comprised of a neural backstepping controller and a robust compensation controller. The neural backstepping controller containing a self-organizing fuzzy neural network (SOFNN) identifier is the principal controller, and the robust compensation controller is designed to dispel the effect of minimum approximation error introduced by the SOFNN identifier. The SOFNN identifier is used to online estimate the chaotic dynamic function with structure and parameter learning phases of fuzzy neural network. The structure learning phase consists of the growing and pruning of fuzzy rules; thus the SOFNN identifier can avoid the time-consuming trial-and-error tuning procedure for determining the neural structure of fuzzy neural network. The parameter learning phase adjusts the interconnection weights of neural network to achieve favorable approximation performance. Finally, simulation results verify that the proposed IABC can achieve favorable tracking performance.

  16. A spatial multi-objective optimization model for sustainable urban wastewater system layout planning.

    Science.gov (United States)

    Dong, X; Zeng, S; Chen, J

    2012-01-01

    Design of a sustainable city has changed the traditional centralized urban wastewater system towards a decentralized or clustering one. Note that there is considerable spatial variability of the factors that affect urban drainage performance including urban catchment characteristics. The potential options are numerous for planning the layout of an urban wastewater system, which are associated with different costs and local environmental impacts. There is thus a need to develop an approach to find the optimal spatial layout for collecting, treating, reusing and discharging the municipal wastewater of a city. In this study, a spatial multi-objective optimization model, called Urban wastewateR system Layout model (URL), was developed. It is solved by a genetic algorithm embedding Monte Carlo sampling and a series of graph algorithms. This model was illustrated by a case study in a newly developing urban area in Beijing, China. Five optimized system layouts were recommended to the local municipality for further detailed design.

  17. An Integrated Model Based on a Hierarchical Indices System for Monitoring and Evaluating Urban Sustainability

    Directory of Open Access Journals (Sweden)

    Xulin Guo

    2013-02-01

    Full Text Available Over 50% of world’s population presently resides in cities, and this number is expected to rise to ~70% by 2050. Increasing urbanization problems including population growth, urban sprawl, land use change, unemployment, and environmental degradation, have markedly impacted urban residents’ Quality of Life (QOL. Therefore, urban sustainability and its measurement have gained increasing attention from administrators, urban planners, and scientific communities throughout the world with respect to improving urban development and human well-being. The widely accepted definition of urban sustainability emphasizes the balancing development of three primary domains (urban economy, society, and environment. This article attempts to improve the aforementioned definition of urban sustainability by incorporating a human well-being dimension. Major problems identified in existing urban sustainability indicator (USI models include a weak integration of potential indicators, poor measurement and quantification, and insufficient spatial-temporal analysis. To tackle these challenges an integrated USI model based on a hierarchical indices system was established for monitoring and evaluating urban sustainability. This model can be performed by quantifying indicators using both traditional statistical approaches and advanced geomatic techniques based on satellite imagery and census data, which aims to provide a theoretical basis for a comprehensive assessment of urban sustainability from a spatial-temporal perspective.

  18. Globalization and Self-Organization in the Knowledge-Based Society

    Directory of Open Access Journals (Sweden)

    Christian Fuchs

    2008-07-01

    Full Text Available In this paper I suggest that a theory of self-organization can be used as a consistent background theory for explaining the dynamics and logics of globalization. Globalization is not confined to the human realm, it is an attribute of all complex, self-organizing systems. Globalization in a synchronous sense means a micro-macro-link where bottom-up-emergence of new qualities in the self-reproduction of complex systems takes place, it is accompanied by a macro-micro-link of top-down-localization. A dynamic interaction between a global and a local level (glocalization results in the permanent overall self-reproduction of the system. Globalization in a diachronic sense means the emergence of a new, higher level of self-organization during a phase of instability and heavy fluctuations by order through fluctuation. Globalization is shaped by a dialectic of change and continuity: in the hierarchy that stems from emergent evolution there are both general aspects of globalization and aspects that are specific for each organizational level. Applying this general notion of globalization to society means that human globalization is both a general process that can be found in all societies and a specific process with emergent qualities in concrete phases of societal development. Globalization processes in modern society are based on structural antagonisms that result in uneven developments in the technosphere, the ecosphere, the economy, polity, and culture. The transition to Postfordist, informational capitalism has been a consequence of the development of the structural antagonisms of Fordism and has been accompanied by a new phase of globalization that has transformed the subsystems of society and has resulted in new antagonism that are an expression of general antagonisms that shape modern societies. Hence we find antagonistic tendencies of contemporary globalization in all subsystems of society that result in both risks and opportunities. Human beings

  19. The potential role of waste biomass in the future urban electricity system

    OpenAIRE

    Jiang, Yu; Werf, van der, Edwin; Ierland, van, Ekko C.; Keesman, Karel J.

    2017-01-01

    The share of intermittent renewable electricity (IRE) in the future urban electricity system is expected to increase significantly. Sufficient back-up capacity is needed in the period when IRE output is low. Bioenergy is both dispatchable and carbon-neutral, and can hence be a promising option to back up IRE. The objective of this study is to explore the potential of urban waste biomass in backing up IRE in an urban electricity system. An urban electricity system model is developed to project...

  20. Designing and implementing a regional urban modeling system using the SLEUTH cellular urban model

    Science.gov (United States)

    Jantz, Claire A.; Goetz, Scott J.; Donato, David I.; Claggett, Peter

    2010-01-01

    This paper presents a fine-scale (30 meter resolution) regional land cover modeling system, based on the SLEUTH cellular automata model, that was developed for a 257000 km2 area comprising the Chesapeake Bay drainage basin in the eastern United States. As part of this effort, we developed a new version of the SLEUTH model (SLEUTH-3r), which introduces new functionality and fit metrics that substantially increase the performance and applicability of the model. In addition, we developed methods that expand the capability of SLEUTH to incorporate economic, cultural and policy information, opening up new avenues for the integration of SLEUTH with other land-change models. SLEUTH-3r is also more computationally efficient (by a factor of 5) and uses less memory (reduced 65%) than the original software. With the new version of SLEUTH, we were able to achieve high accuracies at both the aggregate level of 15 sub-regional modeling units and at finer scales. We present forecasts to 2030 of urban development under a current trends scenario across the entire Chesapeake Bay drainage basin, and three alternative scenarios for a sub-region within the Chesapeake Bay watershed to illustrate the new ability of SLEUTH-3r to generate forecasts across a broad range of conditions.