Chaotic phase synchronization and desynchronization in an oscillator network for object selection

Object selection refers to the mechanism of extracting objects of interest while ignoring other objects and background in a given visual scene. It is a fundamental issue for many computer vision and image analysis techniques and it is still a challenging task to artificial Visual systems. Chaotic phase synchronization takes place in cases involving almost identical dynamical systems and it means that the phase difference between the systems is kept bounded over the time, while their amplitudes remain chaotic and may be uncorrelated. Instead of complete synchronization, phase synchronization is believed to be a mechanism for neural integration in brain. In this paper, an object selection model is proposed. Oscillators in the network representing the salient object in a given scene are phase synchronized, while no phase synchronization occurs for background objects. In this way, the salient object can be extracted. In this model, a shift mechanism is also introduced to change attention from one object to another. Computer simulations show that the model produces some results similar to those observed in natural vision systems.

A network of integrate and fire neurons for visual selection

Biological systems have facility to capture salient object(s) in a given scene, but it is still a difficult task to be accomplished by artificial vision systems. In this paper a visual selection mechanism based on the integrate and fire neural network is proposed. The model not only can discriminate objects in a given visual scene, but also can deliver focus of attention to the salient object. Moreover, it processes a combination of relevant features of an input scene, such as intensity, color, orientation, and the contrast of them. In comparison to other visual selection approaches, this model presents several interesting features. It is able to capture attention of objects in complex forms, including those linearly nonseparable. Moreover, computer simulations show that the model produces results similar to those observed in natural vision systems.

Field on Poincare Group and Quantum Description of Orientable Objects

We propose an approach to the quantum-mechanical description of relativistic orientable objects. It generalizes Wigner`s ideas concerning the treatment of nonrelativistic orientable objects (in particular, a nonrelativistic rotator) with the help of two reference frames (space-fixed and body-fixed). A technical realization of this generalization (for instance, in 3+1 dimensions) amounts to introducing wave functions that depend on elements of the Poincar, group G. A complete set of transformations that test the symmetries of an orientable object and of the embedding space belongs to the group I =GxG. All such transformations can be studied by considering a generalized regular representation of G in the space of scalar functions on the group, f(x,z), that depend on the Minkowski space points xaG/Spin(3,1) as well as on the orientation variables given by the elements z of a matrix ZaSpin(3,1). In particular, the field f(x,z) is a generating function of the usual spin-tensor multi-component fields. In the theory under consideration, there are four different types of spinors, and an orientable object is characterized by ten quantum numbers. We study the corresponding relativistic wave equations and their symmetry properties.

Cross-situational learning of object-word mapping using Neural Modeling Fields

The issue of how children learn the meaning of words is fundamental to developmental psychology. The recent attempts to develop or evolve efficient communication protocols among interacting robots or Virtual agents have brought that issue to a central place in more applied research fields, such as computational linguistics and neural networks, as well. An attractive approach to learning an object-word mapping is the so-called cross-situational learning. This learning scenario is based on the intuitive notion that a learner can determine the meaning of a word by finding something in common across all observed uses of that word. Here we show how the deterministic Neural Modeling Fields (NMF) categorization mechanism can be used by the learner as an efficient algorithm to infer the correct object-word mapping. To achieve that we first reduce the original on-line learning problem to a batch learning problem where the inputs to the NMF mechanism are all possible object-word associations that Could be inferred from the cross-situational learning scenario. Since many of those associations are incorrect, they are considered as clutter or noise and discarded automatically by a clutter detector model included in our NMF implementation. With these two key ingredients - batch learning and clutter detection - the NMF mechanism was capable to infer perfectly the correct object-word mapping. (C) 2009 Elsevier Ltd. All rights reserved.

The effects of temperature on the molecular orientation of zinc phthalocyanine films

Phthalocyanine compounds have been widely investigated as candidate materials for technological applications, which is mainly due to their thermal stability and possibility of processing in the form of thin films. In most applications, the controlled growth of thin films with high crystalline quality is essential. In this study, zinc phthalocyanine (ZnPc) thin films were prepared by evaporation on glass and Au-coated glass substrates with subsequent annealing at different temperatures in ambient atmosphere. The morphological and structural features of 80 nm thick zinc phthalocyanine films were investigated, evidencing an alpha -> beta phase transformation after annealing the films at 200 A degrees C, as indicated by UV-Vis spectroscopy and FTIR analyses. A better uniformity of the annealed films was also evidenced via AFM analysis, which may be of importance for applications where film homogeneity and excellent optical quality are required.

Minimizing the object dimensions in circle and sphere packing problems

Given a fixed set of identical or different-sized circular items, the problem we deal with consists on finding the smallest object within which the items can be packed. Circular, triangular, squared, rectangular and also strip objects are considered. Moreover, 2D and 3D problems are treated. Twice-differentiable models for all these problems are presented. A strategy to reduce the complexity of evaluating the models is employed and, as a consequence, instances with a large number of items can be considered. Numerical experiments show the flexibility and reliability of the new unified approach. (C) 2007 Elsevier Ltd. All rights reserved.

Emotioner och värdegrundsarbete : Om lärare, fostran och elever i en mångkulturell skola

This thesis explores aspects of teachers’ obligation to implement and discuss what are referred to in the Swedish national school curricula as “fundamental values” (“värdegrunden” in Swedish). The aim is to describe and analyze dilemmas in interpretations of and teachers’ work with these fundamental values. Four questions are related to this aim. The first addresses difficulties discussed in conversations between seven upper secondary teachers, during nine meetings over the course of one year. In these conversations the teachers reflected upon how to interpret the fundamental values in relation to their daily practice. The second question focuses on the considerable diversity of Swedish schools and examines the work of the teachers through a perspective of intersectionality. The third question concerns how Martha Nussbaum’s theory of emotions as judgments of value could be used for an understanding of the identified dilemmas. The fourth question focuses on ways in which the participating teachers’ discussions may contribute to a wider discussion about possible aims and circumstances of teachers’ work with the fundamental values. Chapter 2 introduces the theoretical framework of the study, Martha Nussbaum’s (2001) ethical thinking on emotions as judgments of value. She argues that emotions have four common cognitive components. They have (1) external objects, and are directed towards these objects. They are (2) intentional, reflecting a person’s particular point of view, his or her special way of beholding the object, and (3) consist of judgments, i.e. views of how things in the world are. According to Nussbaum’s Aristotelian ethics, emotions also (4) mirror the individual’s vision of what a good human life is like, and the vulnerability of it. The concept of eudaimonia, a fulfilled or flourishing life, is central. Chapter 3 focuses on ideas of ethnicity, and on the specific obligation mentioned in the curriculum of counteracting xenophobia and intolerance in a multicultural society. Chapter 4 discusses various aspects of the teachers’ thoughts on religiosity within Swedish society (often depicted as one of most secular in the world) and within the educational system that is non-denominational. Chapter 5 draws attention to different ways in which the teachers view and teach pupils about sexual orientation. Chapter 6 presents conclusions on potential advantages of and challenges involved in Nussbaum’s Aristotelian theory of emotions, when applied to teachers’ views of and practical work with the fundamental values described in the curriculum. One advantage is that emotions may be intellectually scrutinized and morally assessed, on grounds that are known beforehand and discussed in a democratic process. The non-productive division between emotions, on the one hand, and intellectual and moral capabilities, on the other, is transcended by Nussbaum’s theory. An important challenge is to reflect upon when to discuss the cognitive content of pupils’ emotions, and when it is appropriate to state what is right or wrong, and try to influence pupils accordingly. Keywords: Emotions, vulnerability, values education, religious education, teaching, Martha Nussbaum, ethnicity, religion, sexual orientation.

The meta-object facility typed

The Object Managment Group’s Meta-Object Facility (MOF) is a semiformal approach to writing models and metamodels (models of models). The MOF was developed to enable systematic model/metamodel interchange and integration. The approach is problematic, unless metamodels are correctly specified: an error in a metamodel specification will propagate throughout instantiating models and final model implementations. An important open question is how to develop provably correct metamodels. This paper outlines a solution to the question, in which the MOF metamodelling approach is formalized within constructive type theory.