69,719 research outputs found
Abstract Tensor Systems as Monoidal Categories
The primary contribution of this paper is to give a formal, categorical
treatment to Penrose's abstract tensor notation, in the context of traced
symmetric monoidal categories. To do so, we introduce a typed, sum-free version
of an abstract tensor system and demonstrate the construction of its associated
category. We then show that the associated category of the free abstract tensor
system is in fact the free traced symmetric monoidal category on a monoidal
signature. A notable consequence of this result is a simple proof for the
soundness and completeness of the diagrammatic language for traced symmetric
monoidal categories.Comment: Dedicated to Joachim Lambek on the occasion of his 90th birthda
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OD Maps for Studying Historical Internal Migration in Ireland
We study internal migration in Ireland, an aspect of migration that is little-studied. OD Maps have enabled us to characterise aspects of spatial patterns in county to county migration more effectively than with other techniques. We found that internal migration is relatively local, but relatively national for Dublin. Although migration increased between 1851 and 1911, there was a decrease in more local migration. This work explores the origins of trends that would continue for over a century and had a profound effect on the population geography of the island
A Critical Review of the Magnetoplasmadynamic /MPD/ Thrustor for Space Applications
Magnetoplasmadynamic thrustor for space application
Historical Internal Migration in Ireland
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Büchwald-Hartwig reaction applied to synthesis of new luminescent liquid crystal triarylamines derived from isoxazoles
© 2015 Taylor & Francis Group, LLC. The present work describes the synthesis and characterization of novel series of triarylamines isoxazoles (TAA) addressed to the organic photovoltaic materials. Diarylisoxazoles were synthesized by sequential [3+2] 1,3-dipolar cycloaddition reaction between arylnitrile oxides and selected arylalkenes followed by MnO2-oxidation. Isoxazoles were coupled to diarylamines by Büchwald-Hartwig reaction to afford desired compounds 6a-k. Some TAA display liquid-crystalline behaviour and UV-Vis absorption and fluorescence emission were analysed for all samples of TAA 6a-k
Working with school-refusing young people in Tower Hamlets, London
This study looks at the local context, describing quantitative data from a subset of young people seen within the inner London Tower Hamlets Pupil Referral Unit (PRU) that are extremely socially withdrawn and unable to attend mainstream education. The core aim of this research was to examine the views of professionals who work with and for these young people. Qualitative group interviews were used to gain a deeper understanding of the needs of these young people, what might contribute to their withdrawal from school and what needs to be done to help them reintegrate.
Professionals reported that these young people were highly complex in terms of their needs and presentation and that there is a lack of clarity around what causes these young people to withdraw. They agreed that a more intensive multi-layered intervention was required to meet their needs. Interventions that include gradual socialisation, parental involvement and which address the role of technology were indicated. However, more research is needed to clarify how to effectively intervene
Electron density and temperature measurements in the exhaust of a mpd source
Electron density and temperature profiles measured in exhaust of magnetoplasma-dynamic sourc
Operations planning simulation model extension study. Volume 5: Mariner Jupiter orbiter PL-12-A automated payload (upper stage used)
For abstract, see N75-20432
Injury in Ireland
Injury mortality is the fourth commonest cause of death in Ireland. The treatment of injuries has a major impact on our hospitals and on our budget for health. Long term disability following accidents is a serious problem. The aim of this report is to examine the impact of accidents and
injuries on the Irish population by analysing routine mortality and morbidity data, and to identify in turn those areas where preventive measures could have an impact.
In Section One the literature review details the advantages and disadvantages of each type of routine data source used in this report. The interpretation of data should take account of the constraints of the available data collected. The usefulness of routine data collection is highlighted,
while identifying areas for improvement.
In Section Two the methodology employed in the study is detailed. In Section Three data on hospital admissions over a five-year period 1993-1997 are presented. An overview of injury admissions is presented, followed by further analysis of injury data by both cause and by age
group. In Section Four data on all accident-related deaths over a 17-year period, 1980-1996, are presented, with overall mortality data and mortality data by age group and by major causes of injury death detailed.
In Section Five comparisons are made between the eight health board regions for rates of admissions and deaths due to injury.
In presenting the data we use a matrix format devised and recommended by the International Collaborative Effort on Injury Statistics to display injury simultaneously by cause and intent. The use of a common format will also facilitate regional and international comparisons.
In Section Six the priority recommendations for injury prevention are outlined. The key findings are then discussed and further recommendations are presented with the aim of injury prevention, reduction of disability and improvement in injury surveillance
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