Self Organization Research Papers - Academia.edu (original) (raw)

The sophisticated use of self-organizing materials, which include liquid crystals, block copolymers, hydrogen- and π-bonded complexes, and many natural polymers, may hold the key to developing new structures and devices in many advanced... more

The sophisticated use of self-organizing materials, which include liquid crystals, block copolymers, hydrogen- and π-bonded complexes, and many natural polymers, may hold the key to developing new structures and devices in many advanced technology industries. Synthetic materials are usually designed with only one structure-forming process in mind. However, combination of both complementary and antagonistic interactions in macromolecular systems can create order in materials over many length scales. Here polymer materials that make use of competing molecular interactions are summarized, and the prospects for the further development of such materials through both synthetic and processing pathways are highlighted.

The present work deals with the observed enhancement of the magnetic anisotropy of Co nanoparticles by capping with Ag, and its origin. The studied samples are granular multilayers prepared by sequential sputtering deposition of Co on... more

The present work deals with the observed enhancement of the magnetic anisotropy of Co nanoparticles by capping with Ag, and its origin. The studied samples are granular multilayers prepared by sequential sputtering deposition of Co on amorphous Al $ _ {2} $ ...

The Nasa indigenous group’s Guardia Indígena, whose primary goal is to protect indigenous people and their territories from all types of armed groups, is a nonviolent self-protection organization in Northern Cauca, Colombia. On 5 November... more

The Nasa indigenous group’s Guardia Indígena, whose primary goal is to protect indigenous people and their territories from all types of armed groups, is a nonviolent self-protection organization in Northern Cauca, Colombia. On 5 November 2014, while peace talks were ongoing between the Revolutionary Armed Forces of Colombia (FARC) and the Colombian government, two Guardia Indígena members were shot dead by FARC guerrillas. Without guns or physical violence, indigenous guards captured seven guerrillas responsible for the crime, and, four days later, indigenous organizations held a trial and sentenced the rebels to imprisonment. This article describes those events and investigates how the unarmed guards managed to capture the guerrillas and bring them to trial. The self-organization concept is used to gain insights into the mechanisms and strategies deployed. The mechanisms of the Guardia Indígena include constructing and applying specific social norms and values, developing a common...

Previous research has demonstrated that soft membranes have a coupling between curvature and in-plane orientational order. Defects in the orientational order can induce curvature, and conversely, curvature leads to an effective... more

Previous research has demonstrated that soft membranes have a coupling between curvature and in-plane orientational order. Defects in the orientational order can induce curvature, and conversely, curvature leads to an effective geometrical potential acting on defects [1]. Recently, our group has done simulations which show that the interaction between curvature and defects depends on several important issues, including the baseline curvature of the membrane (flat, cylinder, sphere, torus), the phase of the defects (radial or ...

Pervasive systems are intended to make use of services and components that they encounter in their environment. Such systems are naturally spatial in that they can only be understood in terms of the ways in which components meet and... more

Pervasive systems are intended to make use of services and components that they encounter in their environment. Such systems are naturally spatial in that they can only be understood in terms of the ways in which components meet and interact in space. Rather than treating spatiality separately from system components, researchers are starting to develop computational models in which the entire structure of a pervasive system is modelled and constructed using an explicit spatial model, supporting multi-level spatial reasoning, and adapting autonomously to spatial interactions. In this paper we review current and emerging models of spatial computing for pervasive ecosystems, and highlight some of the trends that will guide future research.

Service Oriented Computing offers a promising approach for global businesses and integrated , virtual enterprises that achieve common business goals. For realizing an exhaustive Service Oriented Architecture, some basic research is still... more

Service Oriented Computing offers a promising approach for global businesses and integrated , virtual enterprises that achieve common business goals. For realizing an exhaustive Service Oriented Architecture, some basic research is still necessary and a consensus has to be reached about key aspects. We argue that one key aspect is a common (meta-) model of enriched service descriptions, especially for all use cases related to service discovery and service selection. A first step towards enriched service description is modelling the service's properties , also known as Quality of Services (QoS). The envisioned service properties are often subsumed either under Quality of Services (QoS) or non-functional properties. Since these terms are used with controversial meanings, they will be discussed here shortly. Functional properties describe what the service does and non-functional properties describe how the service does it. The first step towards using a service is requesting the se...

Animals use diverse forms of communication, from sound signals to body postures. Recent ethological studies have reported a unique syntactic communication of a songbird, the Bengalese finch (Lonchura striata var. domestica). Male... more

Animals use diverse forms of communication, from sound signals to body postures. Recent ethological studies have reported a unique syntactic communication of a songbird, the Bengalese finch (Lonchura striata var. domestica). Male Bengalese finches sing complex courtship songs, which can be reconstructed by finite automata, and female Bengalese finches prefer complex songs, as opposed to monotonous or random ones. These facts suggest that the song syntaxes of male birds may have evolved as a result of sexual selection by female birds. Inspired by this hypothesis, we developed a communication model that is a system coupling different types of automaton, one for song production by males and another for song evaluation by females. We applied this model to study the evolution of syntactic animal communication in terms of the self-organization of coevolving automata. Three types of courting strategies as well as a relationship between the song syntax and female preference emerged. We argu...

We report a systematic investigation of equilibrium states predicted by the statistical theory of vortex patches in a square box, in a channel, and in a square with doubly periodic boundary conditions. The study is limited to initial... more

We report a systematic investigation of equilibrium states predicted by the statistical theory of vortex patches in a square box, in a channel, and in a square with doubly periodic boundary conditions. The study is limited to initial conditions containing negative and positive vortex patches with equal strength and area. It is demonstrated that the symmetry between positive and negative vorticity is, in general, broken by the self-organized states. Direct numerical simulations support the predictions of the vortex patch statistics, but agree with point vortex statistics only in the limiting case of small area vortex patches.

We calculate steady solutions of the Euler equations for any given value of energy and circulation (and angular momentum in the case of a circular domain). A linear relationship between vorticity and stream function is assumed. These... more

We calculate steady solutions of the Euler equations for any given value of energy and circulation (and angular momentum in the case of a circular domain). A linear relationship between vorticity and stream function is assumed. These solutions correspond to the predicted self-organization into a maximum-entropy state, in the limit of strong mixing. Vorticity mixing is then only weakly restricted by the constraint of energy conservation. While maximum-entropy solutions depend in general on the whole probability distribution of vorticity levels, these linearized results depend only on a single control parameter, yet keeping much of the general structure of the problem. A convenient classification of the maximum-entropy states is thus provided. We show furthermore how to extend these linearized results as an expansion in energy, involving successive moments of the vorticity probability distribution. They are applied to a rectangular domain and compared with existing numerical and labor...

Abstract: The collection of wild larvae seed as a source of raw material is a major sub industry of shellfish aquaculture. To predict when, where and in what quantities wild seed will be available, it is necessary to track the appearance... more

Abstract: The collection of wild larvae seed as a source of raw material is a major sub industry of shellfish aquaculture. To predict when, where and in what quantities wild seed will be available, it is necessary to track the appearance and growth of planktonic larvae. One of the most difficult groups to identify, particularly at the species level are the Bivalvia. This difficulty arises from the fact that fundamentally all bivalve larvae have a similar shape and colour. Identification based on gross morphological appearance is limited by the time- ...

Interacting magnetic nanoparticles display a wide variety of magnetic behaviors that are now being gathered in the emerging field of “supermagnetism.” We have investigated how the out-of-equilibrium dynamics in the disordered superspin... more

Interacting magnetic nanoparticles display a wide variety of magnetic behaviors that are now being gathered in the emerging field of “supermagnetism.” We have investigated how the out-of-equilibrium dynamics in the disordered superspin glass (SSG) state of a frozen ferrofluid sample is affected by texturation. Via magnetization relaxation experiments at low temperatures, we were able to estimate superspin correlation lengths for both textured and non-textured samples. The comparison with simulations and experiments on atomic spin glasses shows that the dynamic correlations in SSG's appear to develop in a way reminiscent to those in atomic spin glasses at intermediate time/length scales.

The performance of sequential search can be enhanced by the use of heuristics that move elements closer to the front of the list as they are found. Previous analyses have characterized the performance of such heuristics probabilistically.... more

The performance of sequential search can be enhanced by the use of heuristics that move elements closer to the front of the list as they are found. Previous analyses have characterized the performance of such heuristics probabilistically. In this article, we use amortization to analyze the heuristics in a worst-case sense; the relative merit of the heuristics in this analysis is different in the probabilistic analyses. Experiments show that the behavior of the heuristics on real data is more closely described by the amortized analyses than by the probabilistic analyses.

The importance of the second law of thermodynamics, already called the most metaphysical of all laws of nature, as key to understand the questions of ecology and sustainability is discussed, as well as the a fast paced conceptual... more

The importance of the second law of thermodynamics, already called the most metaphysical of all laws of nature, as key to understand the questions of ecology and sustainability is discussed, as well as the a fast paced conceptual evolution that gained momentum in the last 50 years , changing our view of Nature. Classical thermodynamics, is associated with the tendency to disorganization, while nonlinear irreversible thermodynamics, introduces the concept of emerging ordered dissipative structures, a necessa ry tool to deal with the nature of living beings and its social, economic and ecological aggregates. Most introductory texts in thermodynamics are limited in scope , restricting the expositions to the study of equilibrium systems- meaning the study of idealized, infinitely slow process, hardly a situation encountered by the professional life, and far away from how nature works, as an coherent and complex aggregate of dissipative processes. Dissipative structures are living ( i.e....