209 resultados para Art, Ancient.


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The acceleration of ions with high-power lasers has been a very active field of research during the past 10 years. This paper summarizes the main results obtained in the field, detailing the mechanisms of the acceleration process and the main observed beam characteristics. Perspectives for future development of the field and current and future applications are also discussed. © 2012 by Società Italiana di Fisica.

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An underground work (such as a tunnel or a cavern) has many, well known, environmental qualities such as: no physical barriers crossing the land, less maintenance costs than an analogous surface structure, less expenses for heating and conditioning; a localized emission of noise, gas, dust during operation and, finally, a better protection against seismic actions.
It cannot be forgotten, anyway, that some negative environmental features are present such as, for example, : perturbation, pollution and drainage of the groundwater; settlements; disposal of waste rock.
In the paper the above mentioned concepts are discussed and analysed to give a global overview of all this aspects.

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Ion acceleration driven by high intensity laser pulses is attracting an impressive and steadily increasing research effort. Experiments over the past 10-15 years have demonstrated, over a wide range of laser and target parameters, the generation of multi-MeV proton and ion beams with unique properties, which have stimulated interest in a number of innovative applications. While most of this work has been based on sheath acceleration processes, where space-charge fields are established by relativistic electrons at surfaces of the irradiated target, a number of novel mechanisms has been the focus of recent theoretical and experimental activities. This paper will provide a brief review of the state of the art in the field of laser-driven ion acceleration, with particular attention to recent developments.

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This research project explores the communications’ experiences and practices of
selected grant making and grant seeking organisations, at the point of grant refusal. It was funded by the Charities Aid Foundation, and undertaken through collaboration with the Association of Charitable Foundations (ACF).
The research context is the enhanced competition for funding in which many grant seeking organisations experience the disappointment of refusal; whilst grant makers also face multiple pressures, in responding to grant seekers’ needs. This is an operating environment in which subsequent organisational learning appears demanding.
The aims of the research were to:
- Increase understanding of the communications demands, challenges and
opportunities in giving, receiving and sharing news of grant refusal
- Identify opportunities for organisational learning in these situations, for grant
makers and grant seekers
- Contribute to future practice improvement and development, by drawing on
the reported experiences and practices of participating respondents.

The research focuses on private, formal grant makers (foundations and trusts); and their grant seeking organisational constituencies. It excludes study of public grant makers’ grant refusal processes and those of individuals making personal gifts, direct businesses’ grant making, and grant making by community foundations and by other operating and fundraising charities. A staged research process began in 2008, and field research completed in 2009/2011.

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Aboriginal art has been the source of much contention between art curators, gallery owners, art critics and Aboriginal artists themselves. Early aesthetic debates about whether so-called traditional works should be considered ethnographic or artistic have led, at times, to conflicts over the rights of Aboriginal people to have their works exhibited according to the criteria applied to other kinds of Western artworks. This article explores how the dilemmas of troubled ethno-histories are critically embodied and reconfigured in texture and colour. It considers the problems that silenced histories pose for those responsible for their display to the public. As Aboriginal images often conceal troubled intercultural encounters it asks how artworks can be used to provide a counter-polemic to national rhetoric as artists seek to reshape and improve intergenerational futures. This text is published as a counterpart to the contribution to Disturbing Pasts from the artist Heather Kamarra Shearer.

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Even though computational power used for structural analysis is ever increasing, there is still a fundamental need for testing in structural engineering, either for validation of complex numerical models or to assess material behaviour. In addition to analysis of structures using scale models, many structural engineers are aware to some extent of cyclic and shake-table test methods, but less so of ‘hybrid testing’. The latter is a combination of physical testing (e.g. hydraulic
actuators) and computational modelling (e.g. finite element modelling). Over the past 40 years, hybrid testing of engineering structures has developed from concept through to maturity to become a reliable and accurate dynamic testing technique. The hybrid test method provides users with some additional benefits that standard dynamic testing methods do not, and the method is more cost-effective in comparison to shake-table testing. This article aims to provide the reader with a basic understanding of the hybrid test method, including its contextual development and potential as a dynamic testing technique.