Canada's Greek Moment: Transnational Politics, Activists, and Spies During the Long Sixties

This dissertation examines Greek immigrant homeland politics during the period of Greeces military dictatorship, 1967 to 1974, in Toronto and Montreal. It carefully considers the internal dynamics of anti-junta activism in Canadas Greek populations, but it also contemplates the meanings of external perceptions, particularly from the Canadian state and Canadian public discourse. The study acknowledges the dominant paradigm of Greek immigrants as unskilled workers, however, it demonstrates that this archetype is not monolithic. In many ways, it is challenged by a small number of Greeks who possessed skills to write letters to politicians, create petitions, organize public rallies, and politically mobilize others. At the same time, this dissertation carefully considers Canadas social and political environment and shows how uniquely Canadian politics ran parallel to and informed Greek homeland politics. Transnationalism is used as an analytical tool, which challenges the meaning of local/national borders and the perception that they are sealed containers. The main argument expressed here is that environments shape movements and migrant political culture does not develop in a vacuum. Each chapter deals with specific nuances of anti-junta activism in Toronto and Montreal. Chapter One examines the organized voices of the Greek communitys anti-dictatorship movement. The chapters latter section looks at how the Panhellenic Liberation Movement (PAK), led by Andreas Papandreou, consolidated itself as the main mouthpiece against Greeces authoritarian regime. Chapter Two demonstrates that social movements occurring in Canada meshed neatly with anti-junta sentiment, mobilizing many Canadians against the dictatorship. Chapter Three shows how a few skilled Greeks shaped transnational narratives of resistance in local Greek leftist press. Chapters Four and Five examine RCMP surveillance documents related to local politics in Toronto and Montreal. In doing so, the chapters reveal that regional circumstances, particularly Quebecs Quiet Revolution, shaped security concerns and definitions of Greek subversive activities. Overall, Canadas Greek moment was a complex tale of activism, surveillance, and transnational politics

Reconhecimento de grafos com número de estabilidade quadrático convexo

São apresentados os principais e mais recentes resultados sobre grafos com número de estabilidade quadrático convexo (que são grafos cujo número de estabilidade pode ser determinado através de técnicas de programação quadrática convexa) e descritas algumas estratégias algorítmicas para o reconhecimento de grafos deste tipo em famílias particulares

On edge transitivity of directed graphs

We examine edge transitivity of directed graphs. The class of local comparability graphs is defined as the underlying graphs of locally edge transitive digraphs. The latter generalize edge transitive orientations, while local comparability graphs include comparability, anti-comparability and circle graphs. Recognizing local comperability graphs is NP-complete, however they are differences of comparability graphs. We define dimension so as to generalize that of an edge transitive digraph. Connect proper interval graphs are characterized as exaclty the class of local comparability graphs of dimension one. Finally, a characterization of circle graphs is given also in terms of edge transitivity.Examinamos transitividade em arestas de grafos direcionados. A classe dos grafos de comparabilidade local é definida como os grafos subjacentes dos dígrafos localmente transitivos em arestas. Estes últimos generalizam orientações transitivas em arestas, enquanto que grafos de comparabilidade local incluem os de comparabilidade, anti-comparabilidade e circulares. Reconhecer grafos de comparabilidade local é NP-completo, contudo, eles constituem diferenças de grafos de comparabilidade. Definimos dimensão de modo a generalizar a de um dígrafo transitivo em arestas. Os grafos conexos de intervalo próprio são caracterizados exatamente como a classe dos de comparabilidade local de dimensão um. Finalmente, uma caracterização dos grafos circulares é apresentada em termos de transitividade em arestas

Delivering change: comparing reform at the French and German post offices

This study, using historical explanatory methods, compares two cases of large-scale reform at the French and German post offices. First, what were the causes, patterns, and consequences of change in these post offices? More broadly, how can their patterns of reform shed light on administrative reform? These research questions arise not only from particular organizational realities (financial losses and technological change), but also from shifts in administrative to managerial styles within these organizations, a growing market emphasis, and the rise of New Public Management (NPM). As markets were presumed to be good, privatization (and its business-like components) became an acceptable vehicle of reform; where privatization was not feasible, corporatization was. Here I seek to better understand how the NPM zeitgeist and its related influences led to reform in the two cases (the French post office’s corporatization and the German post office’s partial privatization). In particular, how were these ideas translated into action within the organizations? Finally, I compare the patterns of reform constraints, methods, and outputs at the post offices in order to offer insights for policy-makers and public managers

Trivalent Graph isomorphism in polynomial time

It's important to design polynomial time algorithms to test if two graphs are isomorphic at least for some special classes of graphs. An approach to this was presented by Eugene M. Luks(1981) in the work \textit{Isomorphism of Graphs of Bounded Valence Can Be Tested in Polynomial Time}. Unfortunately, it was a theoretical algorithm and was very difficult to put into practice. On the other hand, there is no known implementation of the algorithm, although Galil, Hoffman and Luks(1983) shows an improvement of this algorithm running in $O(n^3 \log n)$. The two main goals of this master thesis are to explain more carefully the algorithm of Luks(1981), including a detailed study of the complexity and, then to provide an efficient implementation in SAGE system. It is divided into four chapters plus an appendix.Comment: 48 pages. It is a Master Thesi

Clique graphs of chordal and path graphs

We characterize clique graphs of chordal and path graphs. A special class of graphs called expanded trees is introduced. They form a subclass of disk-Helly graphs. It is shown that the clique graph of every chordal (hence path) graph is an expanded tree. In addition, every expanded tree is the clique graph of some path (hence chordal) graph. Different characterizations of expanded trees are described, leading to a polynomial time algorithm for recognizing clique graphs of chordal and path graphs.Nós caracterizamos os grafos clique de grafos cordiais e de caminhos. É apresentada ainda uma classe de grafos chamada árvores expandidas. Elas formam uma sub-classe dos grafos disk-Helly. Mostra-se que o grafo clique de todo grafo cordal (portanto dos de caminho) é uma árvore expandida. Mais ainda, que toda árvore expandida é o grafo clique de algum grafo de caminho (portanto cordal). Diferentes caracterizações de árvores expandidas são descritas, conduzindo a um algoritmo de tempo polinomial para o reconhecimento de grafos nesta classe

Sobre a complexidade de coloração mista

National audienceGrafos mistos são estruturas matemáticas que mesclam características de grafos direcionados e não-direcionados. Formalmente, um grafo misto pode ser definido por uma tripla GM = (V, A, E), onde V , A e E representam, respectivamente, um conjunto de vértices, de arcos e de arestas. Uma k-coloração mista de GM = (V, A, E) é função c : V → {0, . . . , k − 1} tal que c(u) < c(v), se (u, v) ∈ A, e c(u) = c(v), se [u, v] ∈ E. O problema de Coloração Mista consiste em determinar o número cromático misto de GM , denotado por χM (GM ), que é o menor inteiro k tal que GM admite uma k-coloração mista. Esse problema modela variações de problemas de escalonamento que consideram simultaneamente restrições de precedência e de compartilhamento de recursos. Neste trabalho, mostramos que Coloração Mista é N P -difícil para as classes dos grafos cordais, dos grafos linha de grafos bipartidos e dos grafos linha de grafos periplanares

Applications of graph theory to wireless networks and opinion analysis

La teoría de grafos es una rama importante dentro de la matemática discreta. Su uso ha aumentado recientemente dada la conveniencia de los grafos para estructurar datos, para analizarlos y para generarlos a través de modelos. El objetivo de esta tesis es aplicar teoría de grafos a la optimización de redes inalámbricas y al análisis de opinión. El primer conjunto de contribuciones de esta tesis versa sobre la aplicación de teoría de grafos a redes inalámbricas. El rendimiento de estas redes depende de la correcta distribución de canales de frecuencia en un espacio compartido. Para optimizar estas redes se proponen diferentes técnicas, desde la aplicación de heurísticas como simulated annealing a la negociación automática. Cualquiera de estas técnicas requiere un modelo teórico de la red inalámbrica en cuestión. Nuestro modelo de redes Wi-Fi utiliza grafos geométricos para este propósito. Los vértices representan los dispositivos de la red, sean clientes o puntos de acceso, mientras que las aristas representan las señales entre dichos dispositivos. Estos grafos son de tipo geométrico, por lo que los vértices tienen posición en el espacio, y las aristas tienen longitud. Con esta estructura y la aplicación de un modelo de propagación y de uso, podemos simular redes inalámbricas y contribuir a su optimización. Usando dicho modelo basado en grafos, hemos estudiado el efecto de la interferencia cocanal en redes Wi-Fi 4 y mostramos una mejora de rendimiento asociada a la técnica de channel bonding cuando se usa en regiones donde hay por lo menos 13 canales disponibles. Por otra parte, en esta tesis doctoral hemos aplicado teoría de grafos al análisis de opinión dentro de la línea de investigación de SensoGraph, un método con el que se realiza un análisis de opinión sobre un conjunto de elementos usando grafos de proximidad, lo que permite manejar grandes conjuntos de datos. Además, hemos desarrollado un método de análisis de opinión que emplea la asignación manual de aristas y distancias en un grafo para estudiar la similaridad entre las muestras dos a dos. Adicionalmente, se han explorado otros temas sin relación con los grafos, pero que entran dentro de la aplicación de las matemáticas a un problema de la ingeniería telemática. Se ha desarrollado un sistema de votación electrónica basado en mixnets, secreto compartido de Shamir y cuerpos finitos. Dicha propuesta ofrece un sistema de verificación numérico novedoso a la vez que mantiene las propiedades esenciales de los sistemas de votación

Expert System for Crop Disease based on Graph Pattern Matching: A proposal

Para la agroindustria, las enfermedades en cultivos constituyen uno de los problemas más frecuentes que generan grandes pérdidas económicas y baja calidad en la producción. Por otro lado, desde las ciencias de la computación, han surgido diferentes herramientas cuya finalidad es mejorar la prevención y el tratamiento de estas enfermedades. En este sentido, investigaciones recientes proponen el desarrollo de sistemas expertos para resolver este problema haciendo uso de técnicas de minería de datos e inteligencia artificial, como inferencia basada en reglas, árboles de decisión, redes bayesianas, entre otras. Además, los grafos pueden ser usados para el almacenamiento de los diferentes tipos de variables que se encuentran presentes en un ambiente de cultivos, permitiendo la aplicación de técnicas de minería de datos en grafos, como el emparejamiento de patrones en los mismos. En este artículo presentamos una visión general de las temáticas mencionadas y una propuesta de un sistema experto para enfermedades en cultivos, basado en emparejamiento de patrones en grafos.For agroindustry, crop diseases constitute one of the most common problems that generate large economic losses and low production quality. On the other hand, from computer science, several tools have emerged in order to improve the prevention and treatment of these diseases. In this sense, recent research proposes the development of expert systems to solve this problem, making use of data mining and artificial intelligence techniques like rule-based inference, decision trees, Bayesian network, among others. Furthermore, graphs can be used for storage of different types of variables that are present in an environment of crops, allowing the application of graph data mining techniques like graph pattern matching. Therefore, in this paper we present an overview of the above issues and a proposal of an expert system for crop disease based on graph pattern matching