Academic literature on the topic 'Visibility maps'

The phrase “fringe visibility map” here refers to high-resolution images of uniform-thickness single crystal foils showing locally hemispheric deformation (i.e. bent into the shape of a watchglass), and to various mathematical analogs thereof. As the availability of “diffraction information” in direct-space form increases, for example with the availability of HREM and z-contrast lattice images, fringe visibility maps may serve as the direct space analog to Kikuchi maps, i.e. to diffraction pattern maps of Kikuchi line pairs as a function of specimen orientation, and their various cartoonifications.Figures 1 to 3 are schematic Mathematica-generated fringe visibility maps for face-centered, body-centered, and diamond face-centered cubic lattices, respectively. Here we have turned the “locally hemispheric” concept around and drawn fringes visible when one is viewing a spherical particle of the appropriate thickness, along varying beam directions (rather than lattice orientations) parallel to the local radius vector on that sphere.

In the Any-Angle Pathfinding problem, the goal is to find the shortest path between a pair of vertices on a uniform square grid, that is not constrained to any fixed number of possible directions over the grid. Visibility Graphs are a known optimal algorithm for solving the problem with the use of pre-processing. However, Visibility Graphs are known to perform poorly in terms of running time, especially on large, complex maps. In this paper, we introduce two improvements over the Visibility Graph Algorithm to compute optimal paths. Sparse Visibility Graphs (SVGs) are constructed by pruning unnecessary edges from the original Visibility Graph. Edge N-Level Sparse Visibility Graphs (ENLSVGs) is a hierarchical SVG built by iteratively pruning non-taut paths. We also introduce Line-of-Sight Scans, a faster algorithm for building Visibility Graphs over a grid. SVGs run much faster than Visibility Graphs by reducing the average vertex degree. ENLSVGs, a hierarchical algorithm, improves this further, especially on larger maps, with millisecond runtimes even on 6000 x 6000 maps. On large maps, with the use of pre-processing, these algorithms are at least an order of magnitude faster than existing algorithms like Visibility Graphs, Anya and Theta*.

The Gaussian map and its allied visibility map on a unit sphere find wide applications for orientating the workpiece for machining by numerical control machines and for probing by coordinate measurement machines. They also provide useful aids in computerized scene analysis, computation of surface-surface intersection, component design for manufacturing and fabrication procedures. Spherical convex hulls and spherical circles are two geometric constructs used to approximate the Gaussian maps and the visibility maps. The duality and the complementarity of these spherical maps are examined so as to derive efficient algorithms.

La simulation des réflexions lumineuses multiples à l'intérieur d'un environnement nécessite de résoudre une intégrale de premier ordre, récursive infinie, pour laquelle il n'existe pas de solution analytique dans le cas général. Certaines méthodes permettent de donner une solution théorique exacte, mais avec des temps de calcul trop important pour espérer produire plusieurs images par seconde dans un avenir proche. De nombreuses méthodes permettent de réaliser ces calculs de manière plus rapide, mais elles reposent sur des approximations dont les effets sont souvent visibles sur les images produites. Notre objectif est de proposer des solutions permettant de réduire les erreurs de calculs en exploitant deux approches complémentaires : (i) une homogénéisation des termes de l'équation de manière à la résoudre seulement à l'aide de quelques opérateurs simples ; (ii) la prise en compte précise des informations de visibilité pour réduire le biais des méthodes reposant sur une estimation de densité. A terme, notre objectif est de diminuer le coût des requêtes de visibilité de nos deux contributions. Pour cela nous envisageons notamment d'introduire des calculs hiérarchiques de visibilité de façon à amortir le coût global des requêtes<br>Simulating light transfer within a virtual environment requires to solve a first order, infinite recursive integral, that unfortunately doesn't have any solution in general cases. Though theoretically exact solutions exist, their computing time is not adapted to real-time rendering in a near future. Many methods have been proposed for accelerating these computations, but they rely on approximations that often produce visible artifacts on the resulting images. Our goal is to propose some new solutions that can reduce biases with two complementary approaches : (i) a new homogeneous representation of each term of the equation can be used to resolve it using only simple operators ; (ii) considering precise visibility information in order to reduce bias of methods that rely on density estimation. On the long range, we aim at reducing visibility requests costs of each contribution. For that purpose, we particularly plan to introduce hierarchical visibility computations so as to amortize queries cost

This thesis is focused on describing methods of computation of global illumination of 3D graphics scenes in real-time. First chapter contains brief introduction to the issue of global illumination (GI) computation, as well as quick summarisation of principles of most commonly used GI computation approaches. A method of visibility computing for indirect illumination, taking advantage of Imperfect Shadow Mapping, is introduced next. After closer examination of this method and prerequisite algorithms follows a description of its practical implementation, as well as of the structure of simple demonstrative application. Next chapter then contains testing and brief examination and evaluation of resulting program's behaviour. Finally, a possible method extension by means of virtual point light clustering is proposed.

Aquesta tesi tracta del disseny, implementació i discussió d'algoritmes per resoldre problemes de visibilitat i bona-visibilitat utilitzant el hardware grà&#64257;c de l'ordinador. Concretament, s'obté una discretització dels mapes de multi-visibilitat i bona-visibilitat a partir d'un conjunt d'objectes de visió i un conjunt d'obstacles. Aquests algoritmes són útils tant per fer càlculs en dues dimensions com en tres dimensions. Fins i tot ens permeten calcular-los sobre terrenys.<br>In this thesis we design, implement and discuss algorithms that run in the graphics hardware for solving visibility and good-visibility problems. In particular, we compute a discretization of the multi-visibility and good-visibility maps from a set of view objects (points or segments) and a set of obstacles. This computation is carried out for two-dimensional and three-dimensional spaces and even over terrains, which in computational geometry are de&#64257;ned as a 2.5D space.

Les plasticiennes sont sous-représentées aux plus hauts niveaux de la réputation artistique, symbolique et économique alors même qu’elles sont majoritaires au sein des écoles d’art et de la population des plasticien.ne.s. Située au croisement de la sociologie du travail, du genre, de l’art et de l’éducation, cette thèse explique ce paradoxe. Elle analyse la fabrique des inégalités de genre au sein d’une école d’art très prestigieuse et ses effets sur l’entrée, le maintien et l’accès à la réputation de ses diplômé.e.s dans l’art contemporain. La construction genrée des carrières artistiques est mise en évidence grâce à l’articulation de données quantitatives issues d’un palmarès d’artistes (ArtFacts), d’entretiens biographiques et d’observations. Qu’il s’agisse du recrutement dans l’école, de la sélection dans un atelier, des « petits boulots » exercés, d’être invité.e à exposer et d’être représenté.e par une galerie, la disparition progressive des femmes se joue autour de jeux de cooptation. À différents moments de la carrière, des stéréotypes sexués pèsent sur l’évaluation de la qualité artistique des femmes et de leurs œuvres, le stigmate de la maternité restreint leur employabilité et leur hétérosexualisation limite les possibilités d’autopromotion. L’accès aux conventions du monde de l’art contemporain et l’insertion dans des réseaux professionnels, en particulier sur le marché de l’art, sont sexuellement différenciés. Néanmoins, diverses ressources sociales, économiques, scolaires ou institutionnelles permettent à certaines femmes de contourner les contraintes qui pèsent sur les carrières artistiques féminines et d’accéder à la réputation<br>Women artists are underrepresented at the highest levels of artistic, symbolic and economic reputation, although they make up the majority of art school students as well as artists. Drawing on sociology of work, gender, art and education, this PhD dissertation explains this paradox. It analyses the making of gender inequalities within a very prestigious French art school and how these affect the entrance into an artistic career, survival in the profession and access to reputation of its graduates in contemporary art. The joint analysis of quantitative data from an artist ranking (ArtFacts), biographical interviews and ethnographic observations sheds light on the gendered construction of artistic careers. Whether it is during the recruitment by the art school, the selection in a studio, student jobs, the invitation to exhibit one’s work or being represented by a gallery, women’s gradual disappearance plays out in co-optation processes. At different stages in the career, the stigma of motherhood restricts their employability and their heterosexualization limits opportunities for self-promotion. Access to the conventions of the contemporary art world and integration into professional networks, particularly in the art market, are sexually differentiated. Nevertheless, different social, economic, educational or institutional resources allow some women to bypass the constraints weighing on women’s artistic careers, and to gain reputation

Cette étude porte sur les relations interpersonnelles des personnes d’origine subsaharienne habitant la ville de Rabat au Maroc. L’échantillon comprend des hommes et des femmes et inclut à la fois des migrants irréguliers, des étudiants, des stagiaires, des réfugiés, des personnes venues au Maroc pour des raisons médicales ou pour y travailler. L’étude analyse la visibilité et l’invisibilité en tant que concepts mouvants et aucunement dichotomiques. Au-delà des différences de parcours, de conditions de vie et de statut juridique au Maroc, les participants perçoivent tous leur vécu actuel comme transitoire. Point de convergence de ces rencontres, leur quotidien au Maroc est vécu comme un passage, un tremplin, dans l’espoir non pas uniquement d’aller en Europe, mais plutôt de pouvoir (sur)vivre et un jour donner sens à leur vie, s’épanouir, se transformer. Tous désirent obtenir un certain pouvoir d’agir sur leur propre existence.

Cette étude porte sur les relations interpersonnelles des personnes d’origine subsaharienne habitant la ville de Rabat au Maroc. L’échantillon comprend des hommes et des femmes et inclut à la fois des migrants irréguliers, des étudiants, des stagiaires, des réfugiés, des personnes venues au Maroc pour des raisons médicales ou pour y travailler. L’étude analyse la visibilité et l’invisibilité en tant que concepts mouvants et aucunement dichotomiques. Au-delà des différences de parcours, de conditions de vie et de statut juridique au Maroc, les participants perçoivent tous leur vécu actuel comme transitoire. Point de convergence de ces rencontres, leur quotidien au Maroc est vécu comme un passage, un tremplin, dans l’espoir non pas uniquement d’aller en Europe, mais plutôt de pouvoir (sur)vivre et un jour donner sens à leur vie, s’épanouir, se transformer. Tous désirent obtenir un certain pouvoir d’agir sur leur propre existence.

Submitted by Natalie Mendes (nataliermendes@gmail.com) on 2015-07-22T00:52:58Z No. of bitstreams: 1 A noite tem mais luzes - considera??es sobre o desejo l?sbico no romance de Cassandra Rios.pdf: 725975 bytes, checksum: 19cc6cfcc8daaa4a2de209717e83c904 (MD5)<br>Made available in DSpace on 2015-07-22T00:52:58Z (GMT). No. of bitstreams: 1 A noite tem mais luzes - considera??es sobre o desejo l?sbico no romance de Cassandra Rios.pdf: 725975 bytes, checksum: 19cc6cfcc8daaa4a2de209717e83c904 (MD5) Previous issue date: 2014-08-29<br>This study analyzes representations of female homosexuality in the novel A noite tem mais luzes (1968), authored by Cassandra Rios, a writer from S?o Paulo. Cassandra?s literary production is permeated by the lesbian theme?s existence being considered one of the first Brazilian writers to ensure the existence of gay characters as protagonists of her novels. Her work is thus a natural source for us understanding the female homosexual desire?s exposure on Brazilian 1960s. In this meanline, we follow the protagonist?s path Pascale, analyzing lesbian identity that is problematic by character, so we seek to establish a dialogue between theoretical texts and narrative scenes that expose the discourses on lesbian identity in the novel. Here also are investigating whether they are experienced and constructed gender roles perceived as sexually "deviant" on a quest to understanding gender relations? dynamics that underlie these constructs. We seek to further understand what are these subjects? circulation spaces and experiences. The analysis' perspective allows us to place this research in the field of post-structuralist studies, being referenced by theorists like Michel Foucault (1967; 1996; 2012); Judith Butler (2014); Stuart Hall (2003; 2006), among other authors who study identity?s questions. From this work?s analysis we can see the constant changes and mechanisms that underlie identification and visibility?s game, highlighting the conflicts and subjective process such questions and showing it, mainly as a historical building.<br>Este estudo analisa as representa??es da homossexualidade feminina no romance A noite tem mais luzes (1968), de autoria da escritora paulista Cassandra Rios. A produ??o liter?ria de Cassandra ? permeada pela exist?ncia da tem?tica l?sbica sendo considerada uma das primeiras escritoras brasileiras a garantir a exist?ncia de personagens homossexuais enquanto protagonistas de seus romances. Sua obra se constitui, pois, numa fonte singular para a compreens?o da exposi??o do desejo homossexual feminino no contexto brasileiro da d?cada de 1960. Nesse sentido, acompanhamos a trajet?ria da protagonista Pascale analisando a identidade l?sbica que ? problematizada atrav?s da personagem, buscamos assim estabelecer um di?logo entre textos te?ricos e cenas da narrativa que exp?em os discursos sobre a identidade l?sbica no romance. Aqui, tamb?m se investiga como s?o vivenciados e constru?dos os pap?is sexuais tidos como sexualmente ?desviantes?, numa busca de se entender a din?mica das rela??es de g?nero que perpassam essas constru??es. Busca-se, ainda, perceber quais s?o os espa?os de circula??o e viv?ncia desses sujeitos. A perspectiva de an?lise adotada permite situar a pesquisa no campo dos estudos p?s-estruturalistas, sendo referenciada por te?ricos como Michel Foucault (1967; 1996; 2012); Judith Butler (2014); Stuart Hall (2003; 2006), dentre outros te?ricos que estudam a quest?o da identidade. A partir da an?lise da obra ? poss?vel perceber as constantes trocas e mecanismos que permeiam o jogo da identifica??o e visibilidade, evidenciando os conflitos e questionamentos subjetivos a tal processo e evidenciando-o, sobretudo, enquanto constru??o hist?rica.

This doctoral thesis explores under what circumstances executive actors, political parties and interest groups gain visibility in EU (European Union) related debates in the Spanish media for the period 2005-2015. The case of Spain allows exploring aspects so far subjected to little empirical investigations. For example, the motivations of Europhile parties’ to pay attention to the EU, to what extent parties use an EU frame to achieve political goals in a multilevel system of government, or the changing patterns of politicization of EU issues in one of the countries more seriously hit by the euro crisis. The analysis relies on the content analysis of 40.000 stories and 354.000 claims of political actors published in El País and El Mundo from 2005 to 2015. The first chapter, devoted to the analysis of executive actors and political parties, corroborates that political actors react to top-down pressures. Executive actors, those with more media visibility, mainly react to the approval of new EU normative and events, such as European Council meetings, while the visibility of political parties is more associated to European parliament elections. Yet, the thesis shows that political actors do not react only to EU processes and events. Even if European integration is not a politicized issue in Spain, the analysis of public debates on EU affairs show that parties use Europe strategically, as part of their competition to each other in the domestic political arena. Results also illustrate that the euro crisis did not redistribute significantly political actors’ visibility in the media. Even if challenger parties were very critical of most decisions adopted to overcome the crisis, their visibility on EU related public debates did not significantly increase during this critical juncture. Finally, even if European integration is not a politicized issue, as far as the EU is associated with domestic political debates, patterns of media political parallelism emerge. For example, the visibility of secessionist Catalan parties in EU related debates only increases parallel to increasing support for independence in El Mundo. The second chapter, devoted to the analysis of interest groups, corroborates that in this case top-down processes do not play an important role in explaining their visibility in EU related debates. Interest groups do not obtain more media coverage when new normative is discussed at the EU level, not even on those policy areas where the EU has more competences. Yet, stories where new EU regulation in the fields of energy, environment, labor and social issues is discussed, show higher diversity of interest groups than policy domains of economic nature, which are monopolized by few groups. The analysis also shows that debates related to the European parliament and the European Commission are generally associated with a more pluralistic patterns, involving interest groups of different types, than those where the European Council participate. The visibility of interest groups does not increase neither during the approval of new EU normative, nor when their implementation is discussed at domestic level. Interest groups with a role in the implementation process have no visibility in public debates on European affairs, not even on highly politicized issues. Regarding the impact of the euro crisis, it did raise attention to previously excluded groups in EU related debates, such as labor unions or citizens groups. Yet, important differences exist between El Mundo and El País. The analysis of interest groups further corroborates that the media are not passive actors but may be actively involved in the process of giving some actors more attention in public debates to support their political allies.<br>Aquesta tesi doctoral explora les circumstàncies en les que actors de l'executiu, partits polítics i grups d'interès obtenen visibilitat en els debats relacionats amb la UE (Unió Europea), publicats pels mitjans de comunicació espanyols durant el període 2005-2015. El cas d'Espanya permet explorar aspectes poc investigats des d’un punt de vista empíric fins ara. Per exemple, les motivacions per les quals els partits euròfils presten atenció a la UE, fins a quin punt utilitzen un emmarcat europeu per a aconseguir objectius polítics en un sistema de govern multinivell, o els canvis en els patrons de politització dels assumptes europeus en un dels països més afectats per l'Euro crisi. L'estudi es basa en l'anàlisi del contingut de 40.000 notícies i 354.000 afirmacions d'actors polítics, publicats en El País i El Mundo entre 2005 i 2015. El primer capítol, enfocat en l'anàlisi dels actors de l'executiu i els partits polítics, corrobora que els actors polítics reaccionen a pressions top-down. Els actors de l'executiu, aquells amb més visibilitat mediàtica, reaccionen principalment a l'aprovació de nova normativa i esdeveniments europeus, com, per exemple, reunions del Consell Europeu, mentre que la visibilitat dels partits polítics està més associada amb les eleccions al Parlament Europeu. No obstant això, aquesta tesi mostra que els actors polítics no només reaccionen a processos i esdeveniments europeus. Fins i tot si la integració europea no és un assumpte polititzat a Espanya, l'anàlisi dels debats públics sobre assumptes europeus mostra que els partits utilitzen Europa de manera estratègica, com a part de la competició partidista en l’arena política domèstica. Els resultats il·lustren que l'Euro crisi no va implicar una redistribució significativa de la cobertura mediàtica dels actors polítics. Malgrat els partits challenger van ser molt crítics amb la majoria de les decisions adoptades per a superar la crisi, la seva visibilitat en els debats públics relacionats amb la UE no va augmentar significativament durant aquesta conjuntura crítica. Finalment, la tesi mostra que tot i que la integració europea no és un assumpte polititzat, en la mesura en que la UE s'associa amb debats polítics domèstics, emergeixen patrons de paral·lelisme polític en la cobertura mediàtica. Per exemple, la visibilitat dels partits catalans secessionistes en debats on es fa referència a la UE només augmenta paral·lelament a l'increment del suport a la independència a El Mundo. El segon capítol, centrat en l'anàlisi dels grups d'interès, demostra que els processos top-down no juguen un paper important a l’hora d’explicar la seva visibilitat en els debats relacionats amb la UE. Els grups d'interès no obtenen major cobertura mediàtica quan es debat nova normativa europea, ni tan sols en aquells àmbits en els que la UE té més competències. No obstant això, notícies sobre l'aprovació de nova regulació europea en àmbits com l'energia, el medi ambient, el treball o els assumptes socials mostren una major diversitat de grups d'interès que aquelles sobre assumpres econòmics, monopolitzades per pocs grups. L'anàlisi també mostra que els debats relacionats amb el Parlament Europeu i la Comissió Europea, generalment es troben associats amb patrons més plurals, involucrant diferents grups d'interès, que aquells en els quals participa el Consell Europeu. La visibilitat dels grups d'interès no és elevada durant la discussió de normativa a nivell europeu ni tampoc durant el procés d’implementació a nivell domèstic. Els grups d'interès amb un rol en el procés d'implementació no obtenen visibilitat en els debats públics sobre els assumptes europeus, ni tant sols en assumptes molt polititzats. Respecte a l'impacte de l'Euro crisi, aquesta va augmentar l'atenció a grups prèviament exclosos dels debats sobre la UE, com, per exemple, sindicats i grups de ciutadans. No obstant, existeixen diferències importants entre El País i El Mundo. L'anàlisi sobre els grups d'interès corrobora que els mitjans de comunicació no són actors passius, sinó que participen activament en el procés, donant més cobertura mediàtica a determinats actors amb l’objectiu de donar suport als seus aliats polítics.<br>Esta tesis doctoral explora las circunstancias en las que actores del ejecutivo, partidos políticos y grupos de interés obtienen visibilidad en los debates relacionados con la UE (Unión Europea), publicados por los medios de comunicación españoles durante el periodo 2005-2015. El caso de España permite explorar aspectos poco investigados desde un punto de vista empírico hasta el momento. Por ejemplo, las motivaciones por las que los partidos eurófilos prestan atención a la UE, hasta qué punto usan un enmarcado europeo para lograr sus objetivos políticos en un sistema de gobierno multinivel, o los cambios en los patrones de politización de los asuntos europeos en uno de los países más afectados por la Euro crisis. El estudio se basa en el análisis del contenido de 40.000 noticias y 354.000 afirmaciones de actores políticos, publicadas en El País y El Mundo entre 2005 y 2015. El primer capítulo, centrado en el análisis de los actores del ejecutivo y los partidos políticos, corrobora que los actores políticos reacciones a presiones top- down. Los actores del ejecutivo, aquellos con más visibilidad mediática, reaccionan principalmente a la aprobación de nueva normativa y eventos europeos, como, por ejemplo, reuniones del Consejo Europeo, mientras que la visibilidad de los partidos políticos está más asociada con las elecciones al Parlamento Europeo. Sin embargo, esta tesis muestra que los actores políticos no sólo reaccionan a estos procesos y eventos europeos. Incluso si la integración europea no es un asunto politizado en España, el análisis de los debates públicos sobre asuntos europeos muestra que los partidos usan Europa de forma estratégica, como parte de la competición partidista en la arena política doméstica. Los resultados también ilustran que la Euro crisis no implicó una redistribución significativa de la cobertura mediática de los actores políticos. A pesar de que los partidos challenger fueron muy críticos con la mayoría de las decisiones adoptadas para superar la crisis, su visibilidad en los debates públicos relacionados con la UE no aumentó significativamente durante esta coyuntura crítica. Finalmente, la tesis muestra que a pesar de que la integración europea no es un asunto politizado, en la medida en que la UE se asocia con debates políticos domésticos, emergen patrones de paralelismo político en la cobertura mediática. Por ejemplo, la visibilidad de los partidos catalanes secesionistas en debates en los que se hace referencia a Europa solo aumenta paralelamente al incremento del apoyo a la independencia en El Mundo. El segundo capítulo, centrado en el análisis de los grupos de interés, demuestra que los procesos top-down no juegan un papel importante para explicar su visibilidad en los debates relacionados con la UE. Los grupos de interés no obtienen mayor cobertura mediática cuando se debate nueva normativa europea, ni siquiera en aquellos ámbitos en los que la UE tiene más competencias. No obstante, noticias sobre la aprobación de nueva regulación europea en ámbitos como la energía, el medio ambiente, el trabajo o los asuntos sociales muestran una mayor diversidad de grupos de interés que aquellas sobre asuntos económicos, monopolizadas por pocos grupos. El análisis también muestra que los debates relacionados con el Parlamento Europeo y la Comisión Europea, generalmente se encuentran asociados con patrones más plurales, involucrando diferentes grupos de interés, que aquellos en los que participa el Consejo Europeo. La visibilidad de los grupos de interés no es elevada durante la discusión de normativa a nivel europeo ni tampoco durante el proceso de implementación a nivel doméstico. Los grupos de interés con un rol en el proceso de implementación no obtienen visibilidad en los debates públicos sobre los asuntos europeos, ni siquiera en asuntos muy politizados. Con respecto al impacto de la Euro crisis, ésta aumentó la atención a grupos previamente excluidos de los debates sobre la UE, como, por ejemplo, sindicatos y grupos de ciudadanos. No obstante, existen diferencias importantes entre El País y El Mundo. El análisis sobre los grupos de interés corrobora que los medios de comunicación no son actores pasivos, sino que participan activamente en el proceso, dando más cobertura mediática a determinados actores con el objetivo de apoyar a sus aliados políticos.

This work emerged from the interest in studying the increasing use of information and communication tools available on the Internet for strengthening the political activism online and offline. To verify the characteristics and specificities of this new type of collective action and its relation to the question of mediatic visibility, we have chosen as the empirical object the electronic discussion group LGBT National Alliance, created by the Brazilian Association of Lesbian, Gay, Bisexual, Transvestite and Transgender (ABGLT), which has articulated and consolidated the largest LGBT network in Latin America. The comprehension of the functioning mode of this network and its strategic actions required the theoretical and conceptual supply of social networks, collective action, repertories of action and mediatic visibility applied to the practices of interaction and communication of LGBT movements observable both in digital platforms as well as offline activities. Due to the specificities of this object, the empirical study was based on two complementary methodological approaches: content analysis and virtual ethnography. The first one guided the structural analysis and the analysis of the discussion group dynamics, as well as data collection on topics that motivated larger participation, which concentrated on the years 2012 and 2013. The second one based the online participant observation of performances in the network and semistructured interviews carried out with members from all regions of the country. From these procedures, it was selected four representative case studies of the two main paradigmatic axes identified as the guidelines of the activism of the network: the political-institutional antagonism (conflicts with the evangelical countertop); and the mediatic antagonism (conflicts with traditional media). Among the conclusions of the research are: the repertories of action (on network, mediatic, cyberactivists) emerge as strengthening tactics of political activism, aiming at expanding its reverberation in public debate and in the political sphere; the search for mediatic visibility is an imbricated strategy in activist actions which covers the |intermedia| mobilizations on digital platforms and recurrent attempts of guiding journalistic vehicles; online and offline articulations, mobilizations and interventions are correlated and can be started either in spaces of mediated interaction as in the traditional political spaces and vice versa; the mobilization of occasional activists and other informal partners is a strategic practice to visualize and reinforce the mechanisms of pressure; the discussion group is potentially more active in civil conversations for purposes of exchanging information, conjuncture analysis, specialized consulting, planning and evaluation of actions; cyberactivism is notably more successful in situations in which the Internet plays a relevant role in the dissemination of alternative informative channels for the collective awareness and engagement; the association of political activism to a number of mediatic repertories, online and networked has contributed to increasing public visibility, the set of alliances and the support of society around anti-homophobia struggles in the country.<br>O presente trabalho surgiu do interesse em investigar a crescente utilização das ferramentas de informação e comunicação disponíveis na Internet para o fortalecimento do ativismo político online e off-line. Para verificar as características e as especificidades desse novo tipo de ação coletiva e sua relação com a questão da visibilidade midiática, escolhemos como objeto empírico o grupo de discussão eletrônico Aliança Nacional LGBT, criado pela Associação Brasileira de Lésbicas, Gays, Bissexuais, Travestis e Transexuais (ABGLT), que articulou e consolidou a maior rede LGBT da América Latina. A compreensão do modo de funcionamento dessa rede e de suas ações estratégicas exigiu o aporte teórico-conceitual das redes sociais, da ação coletiva, dos repertórios de ação e da visibilidade midiática, aplicados às práticas de interação e comunicação dos movimentos LGBT observáveis tanto no âmbito das plataformas digitais quanto na atuação off-line. Em razão das especificidades desse objeto, o estudo empírico apoiou-se em duas abordagens metodológicas complementares: a análise de conteúdo e a etnografia virtual. A primeira orientou a análise estrutural e da dinâmica do grupo de discussão, assim como a coleta de dados nos tópicos que motivaram maior participação, os quais se concentraram nos anos de 2012 e 2013. A segunda embasou a observação participante online das atuações na rede e as entrevistas semiestruturadas realizadas com membros de todas as regiões do país. A partir desses procedimentos, foram selecionados quatro estudos de caso representativos dos dois principais eixos paradigmáticos identificados como norteadores do ativismo da rede: o antagonismo político-institucional (embates com a bancada evangélica); e o antagonismo midiático (embates com a mídia tradicional). Entre as conclusões da pesquisa estão: os repertórios de ação (em rede, midiáticos, ciberativistas) surgem como táticas de reforço do ativismo político, visando ampliar a sua reverberação no debate público e na esfera política; a busca pela visibilidade midiática é uma estratégia imbricada nas ações ativistas que abrange as mobilizações intermídia nas plataformas digitais e as tentativas recorrentes de pautar os veículos jornalísticos; as articulações, mobilizações e intervenções online e off-line estão correlacionadas, podendo ser iniciadas tanto nos espaços de interação mediada quanto nos espaços políticos tradicionais e vice-versa; a mobilização de ativistas ocasionais e demais parceiros informais é uma prática estratégica para visibilizar e reforçar os mecanismos de pressão; o grupo de discussão é potencialmente mais ativo nas conversações civis para fins de troca de informações, análise de conjuntura, consulta especializada, planejamento e avaliação de ações; o ciberativismo é notadamente mais bem-sucedido nas situações em que a Internet exerce um papel relevante na disseminação de canais informativos alternativos para a conscientização e o engajamento coletivos; a associação do ativismo político a uma série de repertórios midiáticos, online e em rede tem contribuído para ampliar a visibilidade pública, o conjunto de alianças e o apoio da sociedade em torno das lutas anti-homofobia no país.

AbstractMultithreaded programs generally leverage efficient and thread-safe concurrent objects like sets, key-value maps, and queues. While some concurrent-object operations are designed to behave atomically, each witnessing the atomic effects of predecessors in a linearization order, others forego such strong consistency to avoid complex control and synchronization bottlenecks. For example, contains (value) methods of key-value maps may iterate through key-value entries without blocking concurrent updates, to avoid unwanted performance bottlenecks, and consequently overlook the effects of some linearization-order predecessors. While such weakly-consistent operations may not be atomic, they still offer guarantees, e.g., only observing values that have been present.In this work we develop a methodology for proving that concurrent object implementations adhere to weak-consistency specifications. In particular, we consider (forward) simulation-based proofs of implementations against relaxed-visibility specifications, which allow designated operations to overlook some of their linearization-order predecessors, i.e., behaving as if they never occurred. Besides annotating implementation code to identify linearization points, i.e., points at which operations’ logical effects occur, we also annotate code to identify visible operations, i.e., operations whose effects are observed; in practice this annotation can be done automatically by tracking the writers to each accessed memory location. We formalize our methodology over a general notion of transition systems, agnostic to any particular programming language or memory model, and demonstrate its application, using automated theorem provers, by verifying models of Java concurrent object implementations.

The environmental and ecosystem values of wetland are maintained through standardized methods, monitoring ecological ed ecosystems aspects like quality of water bodies, the presence or abundance of species and so on. However, protection initiatives sometimes prove to be insufficient in effectively reducing anthropogenic pressures like intensive agricultural areas, infrastructure, urban settlements and industrial sites. Their presence affects effectively and from a perceptive point of view the landscape of the wetlands. In order to reduce visibility fragmentations of wetlands landscapes, the introduction of the perception analysis in wetland conservation processes could guarantee the integral protection of unique value of wetlands landscape. The visibility analysis method is based on the visual perception: intervisibility maps are created using GIS tools the proposed methodology has been applied to the case study of the southeastern Sicilian wetlands, whose landscape value is highly threatened by human actions.

Abstract Feature modelling is now being used quite extensively in the context of manufacturing of parts. It is shown that the use of features in product models, instead of geometric information only, can be very useful in assembly as well. This is done by introducing two types of assembly features, handling and connection features, and by outlining their usability in several assembly planning modules. It is also shown that in assembly feature modelling the concept of internal freedom of motion can be profitably used. Internal freedom of motion can be represented with visibility maps, which can be transformed using the central projection method. An extension of the central projection method, projecting a visibility map onto a cube, is described.

Herein, we explore using a low size, weight, power, and cost unmanned ground vehicle payload designed specifically for low-visibility environments. The proposed payload simultaneously localizes and maps in GPS-denied environments via waypoint navigation. This solution utilizes a diverse sensor payload that includes wheel encoders, inertial measurement unit, 3D lidar, 3D ultrasonic sensors, and thermal cameras. Furthermore, the resulting 3D point cloud was compared against a survey-grade lidar.

Many higher education staff and students are also parents, yet higher education campuses are often ‘informally designated “child-free”’ (Burford &amp; Hook, 2019, p. 1345). Parents face significant challenges within higher education settings. These challenges can be compounded through inaccessible campus environments (Springer et al., 2009). It is important to consider parents as valued and visible campus users when designing infrastructure, information, and communications.

Homestead National Historical Park (HOME), southeast Nebraska, commemorates the 1862 Homestead Act with series of exhibits, including outdoor ecosystems that represent how the landscape may have appeared historically. The historical, scenic views of HOME have high aesthetic value but are threatened by land use changes, especially construction of tall structures visible over long distances. The impacts of development on scenic views depends on the location and height of constructed objects, topographical variability of the landscape, and the degree of visual obstruction from existing aboveground objects, such as buildings and trees. Viewshed analysis was used to estimate the impacts of development and other forms of landscape change on historic, scenic views within HOME. Two 1-meter [3.28-foot (ft)] landscape elevation datasets, a bare earth digital elevation model (DEM) and a light detection and ranging (LiDAR) digital surface model (DSM), were used to model the minimum height for aboveground object visibility in the 30-mile (mi) radius of HOME. The LiDAR-derived DSM accounted for the effects of aboveground objects on landscape visibility, while the bare earth DEM did not. Minimum height for aboveground object visibility maps were generated for four HOME observation points, based both on the bare earth DEM and LiDAR-derived DSM. Lastly, composite maps of bare earth and LiDAR-derived visibility that combine minimum height class maps across the four observation points were developed. Visibility varied across the radius, among observation points, and between elevation datasets. Despite landscape visibility generally being greater in the bare earth than LiDAR-derived viewshed maps, there was a notable degree of similarity between the bare earth composite and LiDAR-derived composite maps. Overall, visibility is greatest to the southeast and northwest, lesser to the northeast, and lowest to the southwest of HOME. Both the bare earth and LiDAR-derived composite maps indicate that aboveground objects with heights of at least 20 ft are likely to be visible from at least one of the four observation points if they are within 10 mi of HOME. Between 10 mi and 20 mi from HOME, aboveground objects with heights of at least 20–100 ft are likely to be visible if they are located north, but not south, of HOME. Between 20 mi and 30 mi from HOME, aboveground objects less than 400 ft tall are unlikely to be visible, except for small areas to the southeast and northwest. These findings can help inform future viewshed management within HOME and the surrounding landscape.

This presentation - given at Taxonomy Boot Camp 2010 - reports on the effort to integrate, merge and map the Bank's existing vocabularies to provide a common way to consistently classify knowledge products for increased accessibility, visibility, and thus findability both internally and on the web.

This report characterizes night sky conditions in Cumberland Island National Seashore (CUIS) using measurements made in the park unit and models of regional conditions based on satellite data. Calibrated night sky imagery was obtained to characterize the night sky at one site. These ground-based observations were collected on the night of March 9, 2018. Satellite data from 2023 were used to create a map of predicted night sky conditions in and around the park. The sky overhead is influenced by moderate light pollution with a single measurement zenith brightness of 20.86 mag/arcsec2. We estimate more than 43% naked eye stars were visible throughout the data collection period, providing an opportunity to partially view the natural night sky from the park during a cloudless, moonless night. The whole sky over CUIS is 416% brighter than natural levels, indicating that natural night sky conditions are not readily visible, on average. In CUIS, we classified the sky as Bortle Class 4: rural/suburban transition, based on the visibility of astronomical objects. Our Sky Quality Meter (SQM) recorded a single measurement of 20.77 mag/arcsec2, indicating a quality of moderate condition. Obvious light-pollution domes are apparent over population centers in several directions. The zodiacal light is evident but does not extend halfway to the zenith at the beginning or end of twilight. The Milky Way well above the horizon is still impressive but lacks all but the most obvious structure. The main impacts on CUIS’s night sky quality were the light domes from St. Marys, Jacksonville, Yulee, Kings Bay Base, Fernandina Beach, Kingsland, Brunswick, St. Simons, Jacksonville Beach, and Savannah.

This report characterizes night sky conditions in Haleakal? National Park (HALE) using measurements made in the park unit and models of regional conditions based on satellite data. Calibrated night sky imagery was obtained to characterize the night sky at 2 sites. These ground-based observations were collected on 3 nights from 2012-06-12 to 2012-06-14. Satellite data from 2022 was used to create a map of predicted night sky conditions in and around the park. The sky overhead remains pristine with the average zenith brightness of 21.78 mag/arcsec2. We estimate more than 98% of stars were still visible for most of the time, providing an outstanding opportunity to observe the natural night sky from the park. The whole sky over HALE is 11%-18% (mean=14%) brighter than average natural levels, indicating excellent dark sky conditions on average. In HALE, we classified the sky as Bortle Class 3: rural sky, based on the visibility of astronomical objects. The average naked eye limiting magnitude (NELM) is 6.7, which is approaching near pristine under average conditions. Our Sky Quality Meter (SQM) measurements average to 21.74 mag/arcsec2, indicating the zenith is darker than what we can accurately measure with a SQM. Some indication of light pollution is evident along the horizon. Clouds may appear faintly illuminated in the brightest parts of the sky near the horizon but are dark overhead. The Milky Way still appears complex. The main impacts to HALE?s night sky quality were the light domes from Kula, Kihei, Pukalani, Wailea and Kahului. Light domes from these communities were observed along the horizon, although none exceeded the natural brightness of the Milky Way at the time of the study.

This report characterizes night sky conditions in Sequoia and Kings Canyon National Parks (SEKI) using measurements made in the park unit and models of regional conditions based on satellite data. Calibrated night sky imagery was obtained to characterize the night sky at 5 sites. These ground-based observations were collected on 8 nights from 2004-06-12 to 2009-07-21. Satellite data from 2022 was used to create a map of predicted night sky conditions in and around the park. The sky overhead remains pristine with an average zenith brightness of 21.63 mag/arcsec2. We estimate more than 91% of stars were visible throughout the data collection period, providing an excellent opportunity to observe the natural night sky from the park during cloudless, new moon conditions. The whole sky over SEKI is 18%–74% (mean=53%) brighter than average natural levels, indicating impaired dark sky conditions on average. In SEKI, we classified the sky as Bortle Class 4: rural/suburban transition, based on the visibility of astronomical objects. The average naked eye limiting magnitude (NELM) is 6.75, which is approaching near pristine under average conditions. Our Sky Quality Meter (SQM) measurements average 21.74 mag/arcsec2, indicating the zenith is darker than what we can accurately measure with an SQM. Fairly obvious light-pollution domes are apparent over population centers in several directions. The zodiacal light is clearly evident but doesn’t even extend halfway to the zenith at the beginning or end of twilight. The Milky Way well above the horizon is still impressive but lacks all but the most obvious structure. The main impacts on SEKI’s night sky quality were the light domes from Los Angeles, Fresno, Visalia, Bakersfield, Porterville, Clovis, Tulare, Las Vegas, and Hanford. These light domes were observed along the horizon, with a few nearing the natural brightness of the Milky Way.

This report characterizes night sky conditions in Niobrara National Scenic River (NIOB) using measurements made in the park unit and models of regional conditions based on satellite data. Calibrated night sky imagery was obtained to characterize the night sky at 2 sites. These ground-based observations were collected on 2 nights from 2024-08-29 to 2024-08-30. Satellite data from 2022 was used to create a map of predicted night sky conditions in and around the park. The sky overhead remains pristine and unaffected by light pollution with an average zenith brightness of 21.62 mag/arcsec2. We estimate more than 99% of stars were still visible for most of the night, providing a unique and unfettered opportunity to observe the natural night sky from the park. The whole sky over NIOB is 9%–18% (mean=14%) brighter than average natural levels, indicating excellent dark sky conditions on average. In NIOB, we classified the sky as Bortle Class 2: typical truly dark site, based on the visibility of astronomical objects. The average naked eye limiting magnitude (NELM) is 6.75, which is approaching near pristine under average conditions. Our Sky Quality Meter (SQM-L) measurements average 21.44 mag/arcsec2, slightly higher than average natural conditions, elevated by Milky Way and airglow luminance. Natural airglow is apparent along the horizon. M33, the Triangulum Galaxy, is seen rather easily with direct vision. The summer Milky Way is highly structured to the unaided eye and visible down to the horizon. Its brightest regions look like veined marble when viewed with ordinary binoculars. The main impact on NIOB’s night sky quality is the light dome from Valentine, NE, with smaller impacts from Ainsworth, NE, Springview, NE, Sicangu Village, SD and Winner, SD. Of these Valentine is the largest and brightest. From Fort Niobrara, the Valentine light dome is the dominant feature of the landscape, significantly brighter than the Milky Way and any other natural feature, although limited to a small portion of the horizon. From Norden Bridge, the Valentine light dome is still the main source of anthropogenic light, and just slightly brighter than the Milky Way, although its footprint is much smaller at that distance and its impact on the overall scene is minimal.