Sharpness Ratings of a Complete Imaging System

In a complete imaging system, consisting of a camera and a camera lens, four black and white films, an enlarger, a print made from each film and a number of observers, the resultant images were judged subjectively. The system was also evaluated by four acutance models. When the acutance ratings were compared with the sharpness ratings there was not a significant correlation between the two ratings. The author believes that there would be a better correlation between the two ratings if the acutance models were used under the same conditiobs and the same constants as they were formulated under

Digital Control of a Six-Axis Manipulator

This report describes research done at the Artificial Intelligence Laboratory of the Massachusetts Institute of Technology. Support for the laboratory's artificial intelligence research is provided in part by the Advanced Research Projects Agency of the Department of Defense under Office of Naval Research contract NOOO14-75-C-0643.This paper describes a scheme for providing low-level control of a multi-link serial manipulator. The goal was to achieve adaptive behavior without making assumptions about the environment.MIT Artificial Intelligence Laboratory Department of Defense Advanced Research Projects Agenc

William Saroyan, an American interpreter of our times as seen in his short stories and dramas

Thesis (M.A.)--Boston University, 1941. This item was digitized by the Internet Archive

Les empreintes du passe sur la création numérique

Cet article porte sur les traces qu’ont laissées les créateurs du passé sur la création numérique actuelle. Le cinéma, les séries télévisées, les jeux vidéo, la bande dessinée et la publicité, toujours très populaires auprès du public, utilisent encore des procédés qui tirent leur origine dans une culture occidentale forgée par près de deux millénaires de stratégies narratives devenues “classiques”. D’autre part, le 21e siècle est une ère de création de contenus numériques toujours plus riches, accessibles, intégrés, intelligents et interactifs. Un survol historique, des fresques rupestres du paléolithique, en passant par le cinéma des frères Lumière jusqu’à l’invention de l’informatique moderne mettrait rapidement en lumière le profond désir ancestral de l’homme d’être continuellement à la recherche d’espace interactif et/ou immersif.This article focuses on the traces left by the creators of the past on the current digital creation. Movies, television series, video games, comics and advertising, still very popular with the public, all use methods that have their origin in a western culture forged by nearly two millennia of"classic"narrative strategies. On the other hand, the 21st century is an era of creating increasingly rich digital content: accessible, integrated, intelligent and interactive. An historical overview, from the Paleolithic cave paintingsthrough the cinema of the Lumière brothers, to the invention of the modern computer, would quickly light the deep ancestral human desire to continually look for interactiveand / or immersivespace.Este artigo analisa os traços que os criadores do passado deixaram sobre a criação digital atual. Filmes, séries de televisão, jogos de vídeo, quadrinhos e publicidade, sempre populares com o público, ainda usam métodos que têm a sua origem em uma cultura ocidental forjada por quase dois milênios de estratégias narrativas que se tornam "clássicos". Além disso, o século 21 é uma época de criação cada vez mais rica de conteúdo digital, acessível, integrada, inteligente e interativa. Uma visão histórica, das pinturas rupestres paleolíticas, passando pelo cinema dos irmãos Lumière até a invenção do computador moderno traria rapidamente à luz o profundo desejo humano ancestral do homem de estar constantemente à procura de espaço interativo e / ou imersivo

The road to oblivion – quantifying pathways in the decline of large old trees

Large old hollow-bearing trees have a wide range of key ecological roles in forest and other ecosystems globally. Patterns and rates of mortality and decay of these trees had profound effects on the size and composition of their populations. Using an 18-year empirical study of large old trees in the Mountain Ash (Eucalyptus regnans) forests of the Central Highlands of Victoria, we sought to determine if there are particular patterns of decline that are shared by a proportion of the trees in a tree population. We also sought to identify drivers of decline of these trees by quantifying relationships between the condition state of trees (viz: tree form) and a range of covariates. We found that time, stand age and fire can individually and in combination, strongly affect the decay (and eventual collapse) of large old trees. In particular, we found compelling evidence that patterns of tree decline were markedly different in old growth forest (stands dating from ~ 1850) relative to three other younger age classes examined. Trees in older forest decayed less rapidly than trees of equivalent tree form in younger forest. Old growth stands also were characterized by trees in an overall much lower (more intact) form category than the other age classes of forest. A key pattern in our study was the rapid deterioration of large old trees in the youngest aged stands (viz: those regenerating after fires in 1939 and following disturbance between 1960 and 1990). In these forests, a very high proportion of large old trees were either in the most advanced state of tree decay (form 8) or had collapsed (form 9). This is a major concern given that 98.8% of the Mountain Ash forest ecosystem supports forest belonging to these (or even younger) age cohorts. Our investigation highlights the need for forest management to: (1) increase levels of protection for all existing large old hollow-bearing trees, (2) expand the protection of existing regrowth forest so there is the potential to significantly expand the currently very limited areas of remaining old growth forest.The work reported in this paper was funded by the Australian Research Council, The Australian Government (National Environmental Science Program Threatened Species Recovery Hub), and the Government of Victoria

Problems in using social work records in assessing change

Thesis (M.S.)--Boston Universit

Sense of Community in Professional Virtual Communities

Sense of virtual community (feelings of identity, belonging, and attachment) is an essential component of virtual communities. In this chapter, we develop a model of how sense of virtual community develops in professional virtual communities. Based on sense of virtual community models in social virtual communities, we expect that the exchange of support, development of a group identity, and group norms will lead to a stronger professional sense of virtual community. Unlike social virtual communities, we also predict that employee/members occupational identification will increase professional sense of virtual community, particularly when the virtual community can provide support and information not available in the employee/member’s face-to-face life. Finally, we propose that increased occupational commitment, professional networks, and employee performance are outcomes of sense of virtual community in professional virtual communities