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Matemàtica Discreta i Llògica. Teoria i, sobretot, problemes. Versió 2.4
No full textLa versió inicial d'aquest material ha rebut un ajut del Servei de Política Lingüística de la Universitat de València en la convocatòria 2020 d'incentius per a la qualitat lingüística en l'elaboració de materials docents.L'assignatura 34666 - Matemàtica discreta i lògica s'imparteix en primer curs d'Enginyeria Informàtica a la Universitat de València. És una assignatura introductòria que hauria de servir de pont entre conceptes matemàtics, lògics i computacionals, importants a l'hora d'assolir certes competències transversals com ara la capacitat per a representar informació i per a resoldre problemes.
En l'assignatura hi ha quatre blocs principals: combinatòria, lògica, recursió, i estructures gràfiques i arborescents. Encara que en queden fora molts continguts típics de cursos i llibres de matemàtica discreta (com ara resolució de recurrències, codificació, teoria de nombres, etc.), també és veritat que de qualsevol dels quatre blocs es podria impartir una assignatura sencera (encara que no en primer curs).
El tret principal del present manual és la col·lecció de problemes. Es tracta majorment de problemes que han sigut utilitzats en exàmens o en exercicis pràctics. Molts admeten solucions obertes, ramificacions i extensions que poden resultar interessants per a la comprensió dels conceptes relacionats.
Per això s'ha reduït la teoria a l'enumeració de conceptes importants, i s'han estès les solucions de problemes seleccionats perquè il·lustren i expliquen la part teòrica corresponent.
El material no s'hauria d'utilitzar com a apunts complets i autocontinguts, sinó com un resum de conceptes que cal ampliar en altres fonts. Tampoc no s'haurien de considerar les solucions com a respostes tipus que cal estudiar. Al contrari, la millor manera d'aprofitar el material consisteix a intentar seriosament la resolució de cada problema abans de mirar la solució.
El llibre s'ha concebut com un projecte obert, de manera que la col·lecció de problemes puga anar creixent. La idea és que estiga disponible en línia de manera oberta i que es puga navegar fàcilment entre les seues parts.
Finalment, val a dir que aquest projecte s'ha beneficiat d'una manera o d'una altra de material (concret) previ, discussions (discretes) i reflexions (lògiques) amb diversos companys del departament amb qui he tingut el plaer de treballar. Principalment, Fernando Barber, Ignacio García, Sergio Casas, Miguel Lozano i Salva Moreno
Matemàtica Discreta i Lògica. Teoria i, sobretot, problemes. Versió 2.1
Get PDFAquest material ha rebut un ajut del Servei de Política Lingüística de la Universitat de València en la convocatòria 2020 d'incentius per a la qualitat lingüística en l'elaboració de materials docents.L'assignatura 34666 - Matemàtica discreta i lògica s'imparteix en primer curs d'Enginyeria Informàtica a la Universitat de València. És una assignatura introductòria que hauria de servir de pont entre conceptes matemàtics, lògics i computacionals, importants a l'hora d'assolir certes competències transversals com ara la capacitat per a representar informació i per a resoldre problemes.
En l'assignatura hi ha quatre blocs principals: combinatòria, lògica, recursió, i estructures gràfiques i arborescents. Encara que en queden fora molts continguts típics de cursos i llibres de matemàtica discreta (com ara resolució de recurrències, codificació, teoria de nombres, etc.), també és veritat que de qualsevol dels quatre blocs es podria impartir una assignatura sencera (encara que no en primer curs).
El tret principal del present manual és la col·lecció de problemes. Es tracta majorment de problemes que han sigut utilitzats en exàmens o en exercicis pràctics. Molts admeten solucions obertes, ramificacions i extensions que poden resultar interessants per a la comprensió dels conceptes relacionats.
Per això s'ha reduït la teoria a l'enumeració de conceptes importants, i s'han estès les solucions de problemes seleccionats perquè il·lustren i expliquen la part teòrica corresponent.
El material no s'hauria d'utilitzar com a apunts complets i autocontinguts, sinó com un resum de conceptes que cal ampliar en altres fonts. Tampoc no s'haurien de considerar les solucions com a respostes tipus que cal estudiar. Al contrari, la millor manera d'aprofitar el material consisteix a intentar seriosament la resolució de cada problema abans de mirar la solució.
El llibre s'ha concebut com un projecte obert, de manera que la col·lecció de problemes puga anar creixent. La idea és que estiga disponible en línia de manera oberta i que es puga navegar fàcilment entre les seues parts.
Finalment, val a dir que aquest projecte s'ha beneficiat d'una manera o d'una altra de material (concret) previ, discussions (discretes) i reflexions (lògiques) amb diversos companys del departament amb qui he tingut el plaer de treballar. Principalment, Fernando Barber, Ignacio García, Sergio Casas, Miguel Lozano i Salva Moreno.Servei de Política Lingüística de la Universitat de Valènci
Signal processing techniques for robust sound event recognition
Get PDFThe computational analysis of acoustic scenes is today a topic of major interest, with a growing community focused on designing machines capable of identifying and understanding the sounds produced in our environment, similar to how humans perform this task. Although these domains have not reached the industrial popularity of other related audio domains, such as speech recognition or music analysis, applications designed to identify the occurrence of sounds in a given scenario are rapidly increasing. These applications are usually limited to a set of sound classes, which must be defined beforehand. In order to train sound classification models, representative sets of sound events are recorded and used as training data. However, the acoustic conditions present during the collection of training examples may not coincide with the conditions during application testing. Background noise, overlapping sound events or weakly segmented data, among others, may substantially affect audio data, lowering the actual performance of the learned models. To avoid such situations, machine learning systems have to be designed with the ability to generalize to data collected under conditions different from the ones seen during training.
Traditionally, the techniques used to carry out tasks related to the computational understanding of sound events have been inspired by similar domains such as music or speech, so the features selected to represent acoustic events come from those specific domains. Most of the contributions of this thesis are based on how such features are suitably applied for sound event recognition, proposing specific methods to adapt the features extracted both within classical recognition approaches and modern end-to-end convolutional neural networks. The objective of this thesis is therefore to develop novel signal processing techniques aimed at increasing the robustness of the features representing acoustic events to adverse conditions affecting the mismatch between the training and test conditions in model learning. To achieve such objective, we start first by analyzing the importance of classical feature sets such as Mel-frequency cepstral coefficients (MFCCs) or the energies extracted from log-mel filterbanks, analyzing as well the impact of noise, reverberveration or segmentation errors in diverse scenarios. We show that the performance of both classical and deep learning-based approaches is severely affected by these factors and we propose novel signal processing techniques designed to improve their robustness by means of the non-linear transformation of feature vectors along the temporal axis. Such transformation is based on the so called event trace, which can be interpreted as an indicator of the temporal activity of the event within the feature space. Finally, we propose the use of the energy envelope as a target for event detection, which implies the change from a classification-based approach to a regression-oriented one
An analysis of selection sort using recurrence relations
No full textThis paper presents a method for obtaining the expected number of data movements executed by the well-known Selection sort algorithm along with its corresponding variance. The approach presented here requires hardly any specific mathematical background. In particular, the average-case cost and variance are represented using recurrence relations whose solutions lead to the desired results. Even though this method is not applicable in general, it serves to conveniently present average-case algorithm analysis in depth in an elementary course on Algorithm
Eliminación de redundancia en el sistema visual humano : Nueva formulación y aplicaciones a la codificación de imágenes y vídeo
No full textAdaptive Distance-Based Pooling in Convolutional Neural Networks for Audio Event Classification
Get PDFIn the last years, deep convolutional neural networks have become a standard for the development of state-of-the art audio classification systems, taking the lead over traditional approaches based on feature engineering. While they are capable of achieving human performance under certain scenarios, it has been shown that their accuracy is severely degraded when the systems are tested over noisy or weakly segmented events. Although better generalization could be obtained by increasing the size of the training dataset, e.g. by applying data augmentation techniques, this also leads to longer and more complex training procedures. In this paper, we propose a new type of pooling layer aimed at compensating non-relevant information of audio events by applying an adaptive transformation of the convolutional feature maps in the temporal axis. The proposed layer performs a non-linear temporal transformation that follows a uniform distance subsampling criterion on the learned feature space. The experiments conducted over different datasets show significant performance improvements when the proposed layer is added to baseline models, resulting in systems that generalize better to mismatching test conditions and learn more robustly from weakly labeled data
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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