WSOM: Building Adaptive Wavelets with Self-organizing Maps

The WSOM (Wavelet Self-Organizing Map) model, a neural network for the creation of wavelet bases adapted to the distribution of input data, is introduced. The model provides an efficient on-line way to construct high-dimensional wavelet bases. Simulations of a lD function approximation problem illustrate how WSOM adapts to non-uniformly distributed input data, outperforming the discrete wavelet transform. A speaker-independent vowel recognition benchmark task demonstrates how the model constructs high-dimensional bases using low-dimensional wavelets.National Science Foundation (IIU 91-011659); Office of Naval Research (N00014-95-10409, NOOOH-95-0657

S-TREE: Self-Organizing Trees for Data Clustering and Online Vector Quantization

This paper introduces S-TREE (Self-Organizing Tree), a family of models that use unsupervised learning to construct hierarchical representations of data and online tree-structured vector quantizers. The S-TREE1 model, which features a new tree-building algorithm, can be implemented with various cost functions. An alternative implementation, S-TREE2, which uses a new double-path search procedure, is also developed. S-TREE2 implements an online procedure that approximates an optimal (unstructured) clustering solution while imposing a tree-structure constraint. The performance of the S-TREE algorithms is illustrated with data clustering and vector quantization examples, including a Gauss-Markov source benchmark and an image compression application. S-TREE performance on these tasks is compared with the standard tree-structured vector quantizer (TSVQ) and the generalized Lloyd algorithm (GLA). The image reconstruction quality with S-TREE2 approaches that of GLA while taking less than 10% of computer time. S-TREE1 and S-TREE2 also compare favorably with the standard TSVQ in both the time needed to create the codebook and the quality of image reconstruction.Office of Naval Research (N00014-95-10409, N00014-95-0G57

Building Adaptive Basis Functions with a Continuous SOM

This paper introduces CSOM, a distributed version of the Self-Organizing Map network capable of generating maps similar to those created with the original algorithm. Due to the continuous nature of the mapping, CSOM outperforms the traditional SOM algorithm in function approximation tasks. System performance is illustrated with three examples

Building Adaptive Basis Functions with a Continuous Self-Organizing Map

This paper introduces CSOM, a continuous version of the Self-Organizing Map (SOM). The CSOM network generates maps similar to those created with the original SOM algorithm but, due to the continuous nature of the mapping, CSOM outperforms the SOM on function approximation tasks. CSOM integrates self-organization and smooth prediction into a single process. This is a departure from previous work that required two training phases, one to self-organize a map using the SOM algorithm, and another to learn a smooth approximation of a function. System performance is illustrated with three examples.Office of Naval Research (N00014-95-10409, N00014-95-0657

A literatura rumo à modernidade : via Konstanz e Frankfurt

This paper aims to study how two of the most productive German theories from the sixties and seventies of the last century - Hans Robert Jauss' Rezeptionsästhetik and Jürgen Habermas' Kommunikatives Handeln - could be woven together in order to make possible new insights over a particular German literary genre.Este texto tem por objetivo recontextualizar uma das teorias literárias mais produtivas surgidas na segunda metade do século XX, na medida em que ela interagiu com conceitos filosóficos amadurecidos na mesma época. Em particular, pretendemos discutir o modo como a Estética da Recepção, desenvolvida ao longo dos anos 1960 e 1970, na Universidade de Konstanz, pôde e ainda pode proporcionar iluminações à literatura quando associada aos estudos de Jürgen Habermas junto à Escola de Frankfurt, também ao longo daquelas décadas e das seguintes.In diesem Aufsatz soll eine der produktivsten literaturwissenschaftlichen Theorien, die in der zweiten Hälfte des 20. Jahrhunderts entstand, neu betrachtet werden. Das Ziel ist erfolgsversprechend, weil sich diese Theorie mit zeitgenössischen philosophischen Begriffen Jürgen Habermas' auseinandersetzt. Im Besonderen soll untersucht werden, wie die während der sechziger und siebziger Jahre in Süddeutschland entwickelte Rezeptionsästhetik immer noch imstande ist, neue Einsichten auf ein bestimmtes Literaturgenre zu ermöglichen

The Diffusion of Organic Agriculture Based on Agroecological Principles in Two South American Cities (Estudios)

The objective of this research is not only the evaluation of institutional strategies related to the research and development process of organic agriculture, but also socialization and appropriation of agro ecological knowledge in order to contribute to the discussion regarding the importance of organic agriculture alternative movements as an effective way of working and incoming generation in Río Cuarto (Córdoba, Argentina) and in Seropédica (Rio de Janeiro, Brazil). The chosen methodologies were: qualitative research, in-depth interviews with agriculturists and professionals from local institutions, and observation, which is the basis of all researching in social field.El objetivo de esta investigación es la evaluación de estrategias institucionales relacionadas con el proceso de investigación y desarrollo de la agricultura orgánica, así como la socialización y apropiación del conocimiento agroecológico para contribuir a la discusión sobre la importancia de los movimientos alternativos de la agricultura orgánica como forma efectiva de trabajo y generación de ingresos en Río Cuarto (Córdoba, Argentina) y en Seropédica (Río de Janeiro, Brasil). Las metodologías elegidas fueron investigación cualitativa, entrevistas en profundidad con agricultores en diferentes sistemas productivos y profesionales que trabajan en instituciones locales, y observación, que es la base de toda investigación en el campo social

Memória, passagens e permanência da tragédia na literatura alemã

This paper aims to study the literary genre tragedy and investigate how it can be truly identified in the works of two authors of the German Enlightenment and Classicism: G. E. Lessing and F. Schiller. In order to reach this goal, it is necessary first to step back to the Greek antiquity and study the origins of this type of text. Additionally, some titles by Shakespeare and Racine will be taken into consideration as further support of our claims.Este artigo tem como objetivo proceder a um breve levantamento do gênero tragédia e verificar até que ponto ele está realmente representado no Iluminismo e no Classicismo alemão dentro da obra de G. E. Lessing e de F. Schiller. Para tanto, é necessário recuarmos no tempo até a Antiguidade clássica e estudarmos os fundamentos desse tipo de texto. O exame de alguns títulos dos autores propostos será, antes, devidamente respaldado pela apreciação de dois estágios da história da tragédia: em Shakespeare e Racine.Absicht des Aufsatzes ist es, eine kurze Aufhebung der literarischen Gattung Tragödie auszuführen und nachzusehen, inwiefern sie in der deutschen Aufklärung und Klassik besonders in den Werken G. E. Lessings und F. Schillers tatsächlich dargestellt ist. Um dieses Ziel zu erreichen, ist es zuerst einmal notwendig zurück bis zur Antike zu greifen und dort die Grundlinien dieser Art Text zu studieren. Die Untersuchung mancher Titel der erwähnten Dichter wird noch präziser durch die Miteinbeziehung der Werke Shakespeares und Racines in diesen Beitrag