Stability and convergence analysis of a neural model applied in nonlinear systems optimization

A neural model for solving nonlinear optimization problems is presented in this paper. More specifically, a modified Hopfield network is developed and its internal parameters are computed using the valid-subspace technique. These parameters guarantee the convergence of the network to the equilibrium points that represent an optimal feasible solution. The network is shown to be completely stable and globally convergent to the solutions of nonlinear optimization problems. A study of the modified Hopfield model is also developed to analyze its stability and convergence. Simulation results are presented to validate the developed methodology.

Media Education and Brazilian Educational Policies for the Enhancement of Learning

As media education concepts and practices have been disseminated and strengthened in European countries and Americas, the policies responsible for that expansion remain little known, particularly in countries where the achievements have been recently noted. That is the case for Brazil, where there have been new opportunities for media education, considered as a valuable resource to help accomplish goals of the educational system. This paper looks into the contribution of media education to the enhancement of teaching and learning in the context of innovations brought by recent policies of the Brazilian Ministry of Education. After educational reform programmes which brought the opportunity for emerging fields such as media education, we produced teaching material and conducted a series of workshops with students and teachers from state secondary schools. By reading and producing multimedia information about local public services available to young people, pupils learned about democracy, citizenship, civic engagement, media language, and identity. Lessons from our experiment are discussed against the backdrop of education policies being implemented to ameliorate harsh conditions resulting from the recent economic crisis. We suggest that media education can help by creating a learning environment in which the students become aware of the value of educational attainments.

The New Concept of Universal Service in a Digital Networked Communications Environment

Digitization, sophisticated fiber-optic networks and the resultant convergence of the media, communications and information technology industries have completely transformed the communications ecosystem in the last couple of decades. New contingent business and social models were created that have been mirrored in the amended communications regimes. Yet, despite an overhaul of the communications regulation paradigm, the status of and the rules on universal service have remained surprisingly intact, both during and after the liberalization exercise. The present paper looks into this paradox and examines the sustainability of the existing concept of universal service. It suggests that there is a need for a novel concept of universal service in the digital networked communications environment, whose objectives go beyond the conventional internalizing and redistributional rationales and concentrate on communication and information networks as a public good, where not only access to infrastructure but also access to content may be essential.

The Changing Environment of Audiovisual Media. New Technologies, New Patterns of Consumer/Business Behaviour and Their Implications for Audiovisual Media Regulation

Digital TV offers of 200 channels and 500 video-on-demand films, podcasting, mobile television, a new web blog being created every two seconds - these are some of the factual elements depicting contemporary audiovisual media in the digital environment. The present article looks into some of these technological advances and sketches their implications for the markets of media content, in particular as newly emerging patterns of consumer and business behaviour are concerned. Ultimately, it puts forward the question of whether the existing audiovisual media regulatory models, which are still predominantly analogue-based, have been rendered obsolete by the transformed (and continually transforming) digital environment.

Business as Usual? : An Appraisal of the Implementation of the UNESCO Convention on Cultural Diversity into EU’s Media Law and Policies

Irrespective of the diverse stances taken on the effect of the UNESCO Convention on Cultural Diversity in the external relations context, since its wording is fairly open-ended, it is clear to all observers that the Convention’s impact will largely depend on how it is implemented domestically. The discussion on the national implementation of the Convention, both in the policy and in the academic discourses, is only just emerging. The implementation model of the EU could set an important example for the international community and for the other State Parties that have ratified the UNESCO Convention, as both the EU and its Member States acting individually, have played a critical role in the adoption of the Convention, as well as in the longer process of promoting cultural concerns on the international scene. Against this backdrop, this article analyses the extent to which the EU internal law and policies, in particular in the key area of media, take into account the spirit and the letter of the UNESCO Convention on Cultural Diversity. The article seeks to critically evaluate the present state of affairs and make some recommendations for calibration of future policies.

Business as Usual? : The Implementation of the UNESCO Convention on Cultural Diversity and EU Media Law and Policies

Irrespective of the diverse stances taken on the effect of the UNESCO Convention on Cultural Diversity in the external relations context, since its wording is fairly open-ended, it is clear to all observers that the Convention’s impact will largely depend on how it is implemented domestically. The discussion on the national implementation of the Convention, both in the policy and in the academic discourses, is only just emerging, although six years the Convention’s entry into force have passed. The implementation model of the EU can set an important example for the international community and for the other State Parties that have ratified the UNESCO Convention, as both the EU and its Member States acting individually, have played a critical role in the adoption of the Convention, as well as in the longer process of promoting cultural concerns on the international scene. Against this backdrop, this article analyses the extent to which the EU internal law and policies, in particular in the key area of media, take into account the spirit and the letter of the UNESCO Convention on Cultural Diversity. Next to an assessment of the EU’s implementation of the Convention, the article also offers remarks of normative character – in the sense of what should be done to actually attain the objective of protecting and promoting cultural diversity. The article seeks to critically evaluate the present state of affairs and make some recommendations for calibration of future policies.

In Search of Political Influence: Strategic Choices and Media Coverage of Political Parties, Interest Groups and Social Movements in Western European Countries

Outside lobbying is a key strategy for social movements, interest groups and political parties for mobilising public opinion through the media in order to pressure policymakers and influence the policymaking process. Relying on semi-structured interviews and newspaper content analysis in six Western European countries, this article examines the use of four outside lobbying strategies – media-related activities, informing (about) the public, mobilisation and protest – and the amount of media coverage they attract. While some strategies are systematically less pursued than others, we find variation in their relative share across institutional contexts and actor types. Given that most of these differences are not accurately mirrored in the media, we conclude that media coverage is only loosely connected to outside lobbying behaviour, and that the media respond differently to a given strategy when used by different actors. Thus, the ability of different outside lobbying strategies to generate media coverage critically depends on who makes use of them.

Rem : a los dos lados del espejo = (Rem at both sides of the mirror)

Cuando se trata de Rem Koolhaas, su espejo no refleja una sola imagen sino múltiples, es un prisma poliédrico. Su espejo nos devuelve el Rem mediático, el intelectual, el conceptualizador, el constructor, el analista, el periodista, el actor... En el caso de esta investigación, fijamos el punto de mira en el Rem COMUNICADOR. “Rem a los dos lados del espejo” se enmarca en una investigación sobre los medios de comunicación de arquitectura, su reflejo en la producción arquitectónica y viceversa. Se trata de llegar a discernir si comunicación y producción arquitectónica colisionan y confluyen en el caso de grandes comunicadores como Rem Koolhaas, si el mensaje y el medio transmisor adquieren las mismas cualidades. Centrándose en la figura de Rem Koolhaas, la tesis aborda la evolución de su faceta comunicativa y las transformaciones sucesivas en el campo de la comunicación arquitectónica, en paralelo a su evolución conceptual a lo largo de su trayectoria. La investigación, por tanto, no se centra tanto en su componente teórica o en la práctica arquitectónica de OMA, sino en la exposición de su producción al mundo, especialmente a través de sus ensayos y libros. “Delirious New York” y “SMLXL” son un reflejo del momento conceptual en que se inscriben, y contienen mucha información sobre los referentes gráficos que irremediablemente han influido en su composición. Especialmente, la aparición de “SMLXL” supuso un revulsivo para el mundo de la comunicación arquitectónica, porque puso el foco sobre la importancia de dejar atrás un discurso narrativo linea y unifocal, para afrontar la comunicación barajando múltiples variables, y aproximaciones, en un proceso similar al desarrollo de un proyecto de arquitectura. Presenta un diseño muy novedoso y una edición extremadamente cuidada, que atiende a parámetros mucho más ambiciosos que los meramente narrativos. Profundiza en la necesidad de una temática global, planteando cuál es la aproximación más apropiada para cada uno de los proyectos que describe, transmitiendo al lector una percepción más allá de lo estrictamente visual, más próximo a lo sensorial. Además, su enorme repercusión a nivel internacional y el gran interés que despertó (no solamente entre los arquitectos, sino también entre diseñadores gráficos, publicistas, personas provenientes de todo tipo de tendencias artísticas y público en general), provocó la globalización del fenómeno de las publicaciones arquitectónicas y puso de manifiesto la importancia de la comunicación como una disciplina en sí misma, dentro de la producción arquitectónica en la era actual. A pesar de la importancia de “SMLXL” a todos los niveles, la presente tesis plantea que, donde realmente se culmina esa experiencia comunicativa, es en “Content”, al incluir nuevos parámetros relacionados con la fusión conceptual de continente y contenido. Es en esta publicación donde el objeto de la comunicación y la expresión de la misma se convierten en un único elemento, que se rige por leyes similares. En este caso, la ley fundamental es la aplicación hasta sus máximas consecuencias de la “cultura de la congestión”, tanto en el mensaje como en el medio, generando lo que hemos convenido en denominar “comunicación congestiva”. Esta concepción deviene en que necesariamente se materialice como un producto efímero, desechable, casi virtual, porque responde a las condiciones de un momento muy concreto y específico y fuera de ese contexto pierde su significación.. La “cultura de la congestión” empieza a surgir en los planteamientos de Koolhaas en la Architectural Association School of Architecture de Londres, bajo la tutela de Elia Zenghelis. Posteriormente se desarrolla en su manifiesto retroactivo sobre Manhattan, “Delirious New York”, donde declara la guerra abierta al urbanismo del movimiento moderno y afirma que la ciudad realmente contemporánea es aquella que es fruto de un desarrollo no planificado, hiperdensa y posible gracias a los avances tecnológicos de su era. Finalmente comienza a materializarse en la Diploma Unit 9 de la AA, donde entra como profesor en 1975, dejando una huella indeleble en las generaciones posteriores de arquitectos que pasaron dicha unidad. Rem Koolhaas es ante todo un intelectual y por ello, todo el constructo teórico sobre la metrópolis comienza a reflejarse en su obra a través de OMA desde el comienzo de su producción. Podemos decir a grandes rasgos que su carrera está marcada por dos hitos históricos fundamentales que determinan tres etapas diferenciadas en su producción. En sus primeros años de profesión, Koolhaas sigue fascinado por la metrópolis urbana y la aplicación del método paranoico crítico a su producción arquitectónica. Es un arquitecto profundamente surrealista. Entiende este método como una estrategia de conocimiento y aproximación al mundo que le rodea: “dejar salir el inconsciente pero sostenerlo con las muletas de la racionalidad”. Pero lo que en realidad le interesa es su aplicación a la gran escala, el “Bigness”, y por ello, participa en proyectos muy ambiciosos de los que surgen conceptos que, más allá de resultar premiados o no, han dejado una huella ideológica en el devenir de la arquitectura. Entre estos proyectos, cabe destacar su propuesta para el Parque de la Villette o la Très Grande Bibliotèque de París. Sus proyectos de esta época destilan una gran carga conceptual, que devienen en unos interiores sorprendentes pero una apariencia exterior sobria o incluso podríamos decir "povera", por el uso de materiales efímeros, poco habituales en la macro-arquitectura hasta ese momento. Súbitamente, en 1997, explotó el denominado “Efecto Bilbao”, de la mano de Frank Gehry (1). El Museo Guggenheim de Bilbao, con su espectacularidad, sus formas pregnantes e imposibles, impacta al mundo. Nace la era de la “Arquitectura del Espectáculo”; la transformación de la ciudad a través de ICONOS que actúen como nodos de atracción y concentración en torno a los cuales supuestamente se revitaliza la actividad económica, cultural y sociopolítica de la ciudad, como si a través de un único gesto se pudieran regenerar todos los tejidos internos de la urbe. Rem Koolhaas comprende rápidamente que la aproximación a la ciudad ha cambiado y, sobre todo, el mercado. En el mundo de la globalización, la única manera de llegar a materializar el “Bigness”, es encerrando sus ejercicios intelectuales en formas pregnantes, bellas, icónicas, espectaculares. Koolhaas encuentra su marca personal en la estética “Stealth”, proveniente de los aviones de combate facetados para evitar los radares, elaborados en los años 80. De esta época surgen proyectos como la Casa da Música de Oporto o la Biblioteca de Seattle; ambos edificios son iconos facetados, de belleza pregnante, que dejan una huella indeleble en la ciudad y provocan, al igual que el Guggenheim, un cierto efecto de recuperación y revitalización en el entorno en que se asientan, al menos de manera temporal. En cualquier caso, Koolhaas nunca abandona los ejercicios meramente teóricos, pero segrega su actividad en dos: OMA produce aquello que tiene vocación de ser construido y se rige por los parámetros del mercado global y AMO, la otra cara del espejo de Rem, aplica el pensamiento arquitectónico a campos no explorados, sin la dependencia de agentes externos, pudiendo permitirse ser un laboratorio puramente experimental. En este escenario, llega el 11 de septiembre de 2001 y el ataque a las Torres Gemelas de Nueva York tiene efectos devastadores a todos los niveles, significando, en un período de tiempo sorprendentemente corto, un cambio en el orden mundial. Rem Koolhaas da entonces un giro de 180 grados, dirige su mirada hacia China, donde entiende que sus aportaciones tienen un beneficio social más directo que en occidente. (2) Para presentar al mundo su nuevo cambio de rumbo y la creación del “Think Tank” AMO, plantea una gran exposición en la NeueGallerie de Berlín bajo el título de “Content”, experiencia paralela a la edición del libro con el mismo título, que inicialmente nace como “catálogo de la exposición, pero que internamente siempre se concibió como el documento más trascendente en el estudio desde “SMLXL”. Sin embargo, en muchos aspectos se trata de su opuesto: una publicación con formato revista, de tapa blanda, con paginado muy fino, formato de "folleto de supermercado" y contenido hiperdenso. Es un experimento efímero, fugaz, ligero, barato, de “usar y tirar”. De hecho, está fuera de stock, ya no se edita. Probablemente Rem Koolhaas desaprobaría que se hiciera una investigación que pusiera el foco sobre el mismo, porque diez años después de su publicación seguramente opine que su vigencia ha caducado. Sin embargo, muestra con una claridad meridiana el estado conceptual y vital de OMA en el momento de su publicación y representa, además un verdadero hito en la comunicación arquitectónica, un punto de no retorno, el máximo exponente de lo que hemos denominado “comunicación congestiva”. La presente tesis plantea que “Content” contiene la esencia de la mayor aportación de Rem Koolhaas al mundo de la arquitectura: la transformación profunda y definitiva de la comunicación arquitectónica mediante la convergencia del estado conceptual y la transmisión del mismo. Su legado arquitectónico y conceptual ha marcado a todas las generaciones posteriores de manera indeleble. Sus ensayos, sus teorías, sus proyectos y sus edificaciones ya pertenecen a la historia de la arquitectura, sin ninguna duda. Pero es su revisión del concepto de la comunicación en arquitectura lo que ha tenido y tendrá un reflejo inmediato en las generaciones futuras, no solamente en la comunicación sino en su arquitectura, a través de un intercambio biyectivo. El planteamiento a futuro sería determinar qué sucede tras “Content”, tras la hiperdensidad máxima, tras la cultura de la congestión visual; qué es lo que propone Koolhaas y qué se va a plantear también en el mundo de la comunicación arquitectónica. Para ello, estudiaremos en profundidad sus últimos proyectos relacionados con la comunicación, como su propuesta para la Biennale de Arquitectura de Venecia de 2014, su intensa investigación sobre el “Metabolismo” en “Project Japan: Metabolism Talks...”, o la dirección de sus últimos planteamientos territoriales. En los últimos tiempos Rem Koolhaas habla de “Preservación”, de “Sobriedad”, de “Esencialismo”, de “Performance”... El autor intelectual de la cultura de la congestión habla ahora de la “low density”...como no podía ser de otra manera en la otra cara del espejo. En definitiva, el color blanco como suma de todos los colores, todas las longitudes de onda del espectro visible recibidas al tiempo. ABSTRACT When talking about Rem Koolhaas, the mirror does not only reflect one but numerous images: it is nothing but a polyhedral prism. His mirror gives us the image of Rem the media celebrity, the intellectual, the conceptualizer, the builder, the analyst, the journalist, the actor... This research sets the spotlight on Rem the COMMUNICATOR. "Rem on both sides of the mirror" belongs to a research on architectural media, its influence on the architectural production and vice versa. It is aimed at getting to discern whether communication and architectural production collide and converge in the case of great communicators such as Rem Koolhaas, and whether the message and transmission media acquire the same features. Focusing on the figure of Rem Koolhaas, this thesis addresses the evolution of his communicative facet and the successive transformations in the field of architectural communication, parallel to the conceptual evolution he underwent throughout his career. Therefore, this research is not so much focused on his theoretical component or on the OMA’s architectural practice, but on the exhibition of his production to the world, especially through his essays and books. "Delirious New York" and "SMLXL" hold up a mirror to the conceptual moment they are part of, and contain a great deal of information about the graphic references that have inevitably influenced his work. Specially, the launch of "SMLXL" was a salutary shock for the architectural communication world, since it set the spotlight on the importance of leaving a linear and unifocal narrative behind in order to face communication considering multiple variables and approaches, based on a process similar to the development of an architectural project. It offers a very innovative design and an extremely careful editing, which deals with parameters much more ambitious than those merely narrative. It explores the need for a global subject and suggests the most appropriate approach for each of the projects described, giving the reader a closer insight to the sensory that goes beyond what’s strictly visual. In addition, its huge international impact and the great interest shown, not only by architects but also by graphic designers, publishers, people from all kinds of artistic trends and the general public, led to the globalisation of the architectural publications phenomenon and brought the importance of communication as a discipline in itself, within the architectural production in the age at hand, to light. Despite the importance of "SMLXL" at all levels, this thesis suggests that the communication experience really culminates in "Content", for it includes new conceptual parameters associated with the container-content conceptual fusion. It is in this book where the purpose of communication and the expression of such become a single element, ruled by similar laws. In this particular case, the fundamental law is to implement the "culture of congestion" to its extreme consequences in both the message and the media, leading to what we have agreed to refer to as "congestive communication”. This concept leads to its inevitable materialisation into an ephemeral, disposable, almost virtual product, because it meets the conditions of a very concrete and specific time, and outside that context it loses its significance. The "culture of congestion" emerged in Koolhaas’ approaches under the guidance of Elia Zenghelis, in the Architectural Association School of Architecture of London. Subsequently, his retroactive manifesto on Manhattan, "Delirious New York" developed it, waging an all-out war against the modern movement urbanism and maintaining that the really contemporary cities are those hyperdense ones that rise as a result of an unplanned development and thanks to the typical technological advances of their time. Finally it began to materialise in the Diploma Unit 9 of the AA, in which he started lecturing in 1975, leaving an indelible mark on subsequent generations of architects who passed that unit. First and foremost, Rem Koolhaas is an intellectual and, therefore, all the theoretical construct in the metropolis began to be reflected in his work through OMA since the beginnings of his production. Broadly speaking, we can say that his career is influenced by two essential historic events, which determine three different stages in his production. In the early years of his career, Koolhaas was still fascinated by the urban metropolis and the implementation of the paranoiac-critical method to his architectural production. He was then a deeply surreal architect. He understood this method as a knowledge strategy and an approach to the world around him: "let the subconscious out but hold it with the crutches of reasonableness”. However, he was actually interested in its implementation on a broad scale, the "Bigness", and therefore, he took part in ambitious projects that led to the accrual of concepts that, beyond being rewarded, left an ideological impression on the evolution of architecture. These projects included his proposal for the Parc de la Villette or the Très Grande Bibliotèque in Paris. The projects he carried out during this period showed a great conceptual background, which evolved into surprising interiors but a sober, or even "povera", exterior appearance, thanks to the use of ephemeral materials that were atypical in the macro-architecture field until that moment. Suddenly, in 1997, the so-called "Bilbao effect" boomed thanks to Frank Gehry (1). The Guggenheim Museum of Bilbao amazed the world with its spectacular nature and its pregnant and impossible shapes. It was the beginning of the era of “The architecture of spectacle”: the transformation of the city through ICONS that would act as nodes of attraction and gathering, around which the economic, cultural and socio-political activity of the city was supposed to be revitalized, as if through a single gesture all internal tissues of the city could be rebuilt. Rem Koolhaas quickly realized that the approach to the city, and especially to the global market, had changed. In the world of globalisation, the only way to get to materialise such "Bigness" was by keeping his intellectual exercises in pregnant, beautiful, iconic and spectacular shapes. Koolhaas found his personal brand in the Stealth aesthetic, resulting from the eighties American combat aircrafts whose shape was faceted in order to avoid radars. Projects such as the Casa da Música in Porto or the Seattle Library date from this period; both buildings are faceted icons of pregnant beauty that left an indelible mark on the city and caused, like the Guggenheim, some degree of recovery and revitalization on the environment in which they were based, at least temporarily. In any case, Koolhaas never gave the merely theoretical exercises up, but he segregated his work in two: OMA produced what was destined to be built and ruled by the parameters of the global market and AMO, Rem’s other side of the mirror, applied the architectural thought in unexplored fields, notwithstanding external agents and being able to work as a purely experimental laboratory. In light of this backdrop, September 11th 2001 came and the attacks on the Twin Towers in New York had devastating effects at all levels, leading to a change in the world order, in a surprisingly short period of time. Rem Koolhaas made a 180° turn directing his vision towards China, where he believed his contributions would have a more direct social benefit than in the Western world. (2) In order to introduce his new course of direction and the creation of the AMO "Think Tank", he planned a major exhibition in the Neue Nationalgalerie of Berlin under the title "Content", in parallel with edition of the book with the same title, which was at first the "exhibition catalog” but, deep down, was always conceived as the most important document of the Office since "SMLXL". However, in many ways it was just the opposite: a publication characterised by its magazine format, soft cover, very fine paging, "supermarket brochure" form and hyperdense content. It was an ephemeral, brief, light, cheap and "disposable" experiment. In fact, it is currently out of stock and out of print. Rem Koolhaas would probably disapprove of a research that sets the spotlight on him, for he would probably say that his validity has expired given that it has been ten years since its publication. However, it shows OMA’s conceptual and vital status at the time of its publication with crystalline clarity and it is also a true milestone in architectural communication. A point of no return. The epitome of the so-called "congestive communication ". This thesis suggests that "Content" contains the essence of Rem Koolhaas’ greatest contribution to the world of architecture: the deep and definitive transformation of architectural communication through the convergence of the conceptual state and the transmission thereof. His architectural and conceptual legacy has left an indelible mark on all subsequent generations. There is no doubt his essays, theories, projects and buildings already belong to the history of architecture. But it is his review on the concept of communication in architecture that has had and shall have an immediate influence on future generations, not only in their communication but also in their architecture, through a bijective exchange. Future approaches should try to determine what happens after "Content", after the maximum hyperdensity, after the visual culture of congestion; what shall Koolhaas suggest as well as what shall happen in the world of architectural communication. To this end, we shall study his latest communication-related projects, such as the design of the Venetian Architecture Biennale in 2014, his intensive research on the "Metabolism" in "Project Japan: Metabolism Talks ...", or the course of his latest territorial approaches in depth. Most recently, Rem Koolhaas has talked about "Preservation", "Sobriety" of "Essentialism", "Performance", etc. The mastermind of the culture of congestion now speaks of the "low density"... as it could not be otherwise, on the other side of the mirror. Summarizing, the white color as the sum of all colors; all wavelengths of the visible spectrum received at the same time.

"Another Way": The Pneumatology of Deleuzean Minoritarian Communal Interpretation in Scripture, the 16th Century Radical Reformation, and Alternative 21st Century Anabaptist Community

This dissertation proposes a constructive theology of the Holy Spirit called the "pneumatology of minoritarian communal interpretation," the alternative creation of meaning within an oppressive majority context. It illustrates the convergence of Deleuzean philosophy with Anabaptist pneumatology and media communal interpretation theory in three particular locations: 1) selected mentions of the Holy Spirit in the Hebrew Bible and Christian New Testament; 2) the 16th century Radical Reformation; and 3) "Another Way," a 21st century alternative Anabaptist group focused around the spiritual discussion of art and popular media. Chapter One outlines the three theories. Chapter Two examines the Holy Spirit in the Hebrew Bible, particularly 1 Samuel 8, the book of Ezekiel, and the Gospel narratives. Chapter Three examines the pneumatological writings of the Radical Reformers, concentrating particularly on their theologies of the intersection between church and the surrounding majoritarian culture. Chapter Four outlines my original field research with Another Way, and examines the tension between minoritarian communal interpretation and the 21st century semiotic regime. Chapter Five then summarizes the conversations between theory and illustration to propose the pneumatology of minoritarian communal interpretation for Christian theology.

Convergence analysis and validation of low cost distance metrics for computational cost reduction of the Iterative Closest Point algorithm

The Iterative Closest Point algorithm (ICP) is commonly used in engineering applications to solve the rigid registration problem of partially overlapped point sets which are pre-aligned with a coarse estimate of their relative positions. This iterative algorithm is applied in many areas such as the medicine for volumetric reconstruction of tomography data, in robotics to reconstruct surfaces or scenes using range sensor information, in industrial systems for quality control of manufactured objects or even in biology to study the structure and folding of proteins. One of the algorithm’s main problems is its high computational complexity (quadratic in the number of points with the non-optimized original variant) in a context where high density point sets, acquired by high resolution scanners, are processed. Many variants have been proposed in the literature whose goal is the performance improvement either by reducing the number of points or the required iterations or even enhancing the complexity of the most expensive phase: the closest neighbor search. In spite of decreasing its complexity, some of the variants tend to have a negative impact on the final registration precision or the convergence domain thus limiting the possible application scenarios. The goal of this work is the improvement of the algorithm’s computational cost so that a wider range of computationally demanding problems from among the ones described before can be addressed. For that purpose, an experimental and mathematical convergence analysis and validation of point-to-point distance metrics has been performed taking into account those distances with lower computational cost than the Euclidean one, which is used as the de facto standard for the algorithm’s implementations in the literature. In that analysis, the functioning of the algorithm in diverse topological spaces, characterized by different metrics, has been studied to check the convergence, efficacy and cost of the method in order to determine the one which offers the best results. Given that the distance calculation represents a significant part of the whole set of computations performed by the algorithm, it is expected that any reduction of that operation affects significantly and positively the overall performance of the method. As a result, a performance improvement has been achieved by the application of those reduced cost metrics whose quality in terms of convergence and error has been analyzed and validated experimentally as comparable with respect to the Euclidean distance using a heterogeneous set of objects, scenarios and initial situations.

Le role des politiques monétaires et la convergence macroeconomique sur le développement des systèmes financiers dans les pays du sud de la Méditerranée. = The role of monetary policies and macroeconomic convergence in the development of financial systems in south Mediterranean countries. MEDPRO Technical Report No. 12/April 2012

This MEDPRO Technical Report shows that the monetary and exchange rate policies conducted by central banks in the South Mediterranean region display apparent homogeneity in their operational frameworks, albeit with some specificities and differing degrees of advancement. While central banks state that price stability is their ultimate objective, failures to control interest rates as operational objectives of monetary policy result in monetary authorities resorting to quantitative approaches to monetary policy, meaning that monetary aggregates and credit targets are being used as intermediate targets of monetary policy. An econometric exercise limited to Maghreb countries (Algeria, Morocco, and Tunisia) has been conducted to analyse the potential scenarios of convergence and monetary policy coordination. Given the high structural heterogeneity and the slow pace of real convergence due to weak commercial integration in the Maghreb, results nevertheless show alternative dynamics in the integration of effective nominal exchange rates, as well as a complete convergence dynamic in exchange rate policies. Partial convergence of monetary policies regarding the stabilisation of inflation rates remains an open option for a transitional phase where financial integration is low.

Subgeometric rates of convergence for a class of continuous-time Markov process

Let (Phi(t))(t is an element of R+) be a Harris ergodic continuous-time Markov process on a general state space, with invariant probability measure pi. We investigate the rates of convergence of the transition function P-t(x, (.)) to pi; specifically, we find conditions under which r(t) vertical bar vertical bar P-t (x, (.)) - pi vertical bar vertical bar -> 0 as t -> infinity, for suitable subgeometric rate functions r(t), where vertical bar vertical bar - vertical bar vertical bar denotes the usual total variation norm for a signed measure. We derive sufficient conditions for the convergence to hold, in terms of the existence of suitable points on which the first hitting time moments are bounded. In particular, for stochastically ordered Markov processes, explicit bounds on subgeometric rates of convergence are obtained. These results are illustrated in several examples.

Media guidelines on the reporting of suicide

There is strong evidence for the existence of the Werther effect, or the phenomenon of an observer copying suicidal behavior he or she has seen modelled in the media. As a consequence, a number of countries have developed guidelines that promote responsible reporting of suicide. Using nine such guidelines as examples, this paper demonstrates that they tend to have similar content (emphasizing, for example, that suicide should not be,glamorized or sensationalized and that explicit descriptions should be avoided, and stressing the importance of providing information about help services), but differ in the way in which they have been developed (e.g., the extent to which media professionals have been involved) and implemented (e.g., whether their roll-out has involved a considered dissemination strategy). The paper also reviews the evidence from evaluations of media guidelines, and concludes that it is too limited to determine whether the guidelines have had an impact on the behavior of media professionals or on completed and attempted suicide rates. It makes recommendations for further evaluative work, and suggests that the lessons from well-designed evaluations should be shared.

The relationship between media reporting of suicide and actual suicide in Australia

This study aimed to determine whether media items about suicide were associated with differential increases in actual suicides. Data were available on 4635 suicide-related items appearing in Australian newspapers and on radio and television news and current affairs shows between March 2000 and February 2001. These data were combined with national data on completed suicides occurring during the same period, by a process that involved identifying the date and geographical reach of the media items and determining the number of suicides occurring in the same location in selected weeks pre- and post-item. Regression analyses were conducted to determine whether the likelihood of an increase in post-item suicides could be explained by particular item characteristics. We found that 39% of media items were followed by an increase in mate suicides, and 31% by an increase in female suicides. Media items were more likely to be associated with increases in both male and female suicides if they occurred in the context of multiple other reports on suicide (versus occurring in isolation), if they were broadcast on television (versus other media), and if they were about completed suicide (versus attempted suicide or suicidal ideation). Different item content appeared to be influential for males and females, with an increase in male suicides being associated with items about an individual's experience of suicide and opinion pieces, and an increase in female suicides being associated with items about mass- or murder-suicide. Item prominence and quality were not differentially associated with increases in male or female suicides. Further research on this topic is required, but in the meantime there is a need to remain vigilant about how suicide news is reported. Mental health professionals and suicide experts should collaborate with media professionals to try to balance 'public interest' against the risk of harm. (c) 2005 Published by Elsevier Ltd.