3,767 research outputs found
Identity and Search in Social Networks
Social networks have the surprising property of being "searchable": Ordinary
people are capable of directing messages through their network of acquaintances
to reach a specific but distant target person in only a few steps. We present a
model that offers an explanation of social network searchability in terms of
recognizable personal identities: sets of characteristics measured along a
number of social dimensions. Our model defines a class of searchable networks
and a method for searching them that may be applicable to many network search
problems, including the location of data files in peer-to-peer networks, pages
on the World Wide Web, and information in distributed databases.Comment: 4 page, 3 figures, revte
The influence of the Book of Common Prayer on the prose style of Samuel Johnson\u27s prayers
Somewhere is most general histories and outlines of English literature, the greatness of the King James Bible and its influence on all of English literature since 1611 have been pointed out. Unquestionably, all men of letters in the English language since that time have known of the King James Bible; and many of them may have been decidedly influenced by its tradition of cadenced prose and its prose figures.
The great deal of research would have to be done in order to establish conclusively the influence of the Prayer Book upon all writers from 1549 to the present time. If this thesis stimulates any other worker to make a study in the general problem, it will have far exceeded its present purposes. For this approaches only one small aspect of the problem.
Samuel Johnson is an obvious subject for such a study, because he attended the Church of England;1 he knew the Prayer Book well;2 in fact, he was such a good Church of England man that Boswell records in the Life at least two occasions when Johnson was offered a position in the Church.33 Furthermore, Johnson was preeminently a prose writer and used an ornate style. This combination of devoutness and literary ability makes of him ripe material for an investigation of the influence of the Prayer Book on an English writer.
There is another reason why Johnson should make a good subject for study. He lived in an age that was a part of the same Renaissance tradition that produced the Bible and the Prayer Book. In fact, it has been pointed out that Johnson was the last of the great Renaissance humanists.4.
The problem that this study attempts to solve, then, is Did the Book of Common Prayer have any influence on Samuel Johnson\u27s prose style? Although many other problems have arisen in the course of this work, no attempt will be made to solve any of them; showing that the Prayer Book did influence at least part of Johnson\u27s writing will be the single purpose of this pape
Combustor concepts for aircraft gas turbine low-power emissions reduction
Several combustor concepts were designed and tested to demonstrate significant reductions in aircraft engine idle pollutant emissions. Each concept used a different approach for pollutant reductions: the hot wall combustor employs a thermal barrier coating and impingement cooled liners; the recuperative cooling combustor preheats the air before entering the combustion chamber; and the catalytic converter combustor is composed of a conventional primary zone followed by a catalytic bed for pollutant cleanup. The designs are discussed in detail and test results are presented for a range of aircraft engine idle conditions. The results indicate that ultralow levels of unburned hydrocarbons and carbon monoxide emissions can be achieved
Experimental evaluation of combustor concepts for burning broad property fuels
A baseline CF6-50 combustor and three advanced combustor designs were evaluated to determine the effects of combustor design on operational characteristics using broad property fuels. Three fuels were used in each test: Jet A, a broad property 13% hydrogen fuel, and a 12% hydrogen fuel blend. Testing was performed in a sector rig at true cruise and simulated takeoff conditions for the CF6-50 engine cycle. The advanced combustors (all double annular, lean dome designs) generally exhibited lower metal temperatures, exhaust emissions, and carbon buildup than the baseline CF6-50 combustor. The sensitivities of emissions and metal temperatures to fuel hydrogen content were also generally lower for the advanced designs. The most promising advanced design used premixing tubes in the main stage. This design was chosen for additional testing in which fuel/air ratio, reference velocity, and fuel flow split were varied
A Twenty Years Phenological Record of the Spring Flowering Plants of Henry County
Each spring since 1915 a record of the date of the first appearance of flowers of our seed bearing plants has been kept. This has been handled through a contest with the students in the botany classes. Reports on the comparative dates for some of the more representative species were made in 1918 and in 1924
Exploring positive adjustment in HIV positive African women living in the UK
This published version of this article has been made available through Open Access by the Brunel University Open Access Publishing Fund and can be accessed at the link below - Copyright @ 2011 Taylor & FrancisResearch into living with HIV/AIDS has to date mainly focused on quality of life and there is little on the adjustment process for this group. The numbers of African women living with HIV/AIDS in the UK is growing and yet little is known about the adjustment experience for these women. This study explored aspects of positive adjustment to living with HIV/AIDS among a sample of African women living in London, UK. Transcripts of semi-structured interviews with 12 women were analysed using interpretative phenomenological analysis (IPA). Two superordinate themes emerged inductively from the data: positive changes in coping (subthemes: positive interpretation of their situation and positive behavioural changes) and positive growth since the HIV diagnosis (subthemes: changes in the value of life and, changes in goals and opportunities). While these women acknowledged the negative impact of living with HIV/AIDS, all participants mentioned changes in health behaviours to help regain mastery of their lives and comparing with others better-off and worse-off was used to enhance self-esteem and view their situation positively. The data show evidence for Taylor's Cognitive Adaptation Theory
Broad specification fuels combustion technology program
Design and development efforts to evolve promising aircraft gas turbine combustor configurations for burning broadened-properties fuels were discussed. Design and experimental evaluations of three different combustor concepts in sector combustor rig tests was conducted. The combustor concepts were a state of the art single-annular combustor, a staged double-annular combustor, and a short single-annular combustor with variable geometry to control primary zone stoichiometry. A total of 25 different configurations of the three combustor concepts were evaluated. Testing was conducted over the full range of CF6-80A engine combustor inlet conditions, using four fuels containing between 12% and 14% hydrogen by weight. Good progress was made toward meeting specific program emissions and performance goals with each of the three combustor concepts. The effects of reduced fuel hydrogen content, including increased flame radiation, liner metal temperature, smoke, and NOx emissions were documented. The most significant effect on the baseline combustor was a projected 33% life reduction, for a reduction from 14% to 13% fuel hydrogen content, due to increased liner temperatures
A portfolio of powertrains for the UK: An energy systems analysis
AbstractThere has recently been a concerted effort to commence a transition to fuel cell vehicles (FCVs) in Europe. A coalition of companies released an influential McKinsey-coordinated report in 2010, which concluded that FCVs are ready for commercial deployment. Public–private H2Mobility programmes have subsequently been established across Europe to develop business cases for the introduction of FCVs. In this paper, we examine the conclusions of these studies from an energy systems perspective, using the UK as a case study. Other UK energy system studies have identified only a minor role for FCVs, after 2030, but we reconcile these views by showing that the differences are primarily driven by different data assumptions rather than methodological differences. Some energy system models do not start a transition to FCVs until around 2040 as they do not account for the time normally taken for the diffusion of new powertrains. We show that applying dynamic growth constraints to the UK MARKAL energy system model more realistically represents insights from innovation theory. We conclude that the optimum deployment of FCVs, from an energy systems perspective, is broadly in line with the roadmap developed by UK H2Mobility and that a transition needs to commence soon if FCVs are to become widespread by 2050
Characterising the Evolution of Energy System Models Using Model Archaeology
In common with other types of complex models, energy system models have opaque structures, making it difficult to understand both changes between model versions and the extent of changes described in research papers. In this paper, we develop the principle of model archaeology as a formal method to quantitatively examine the balance and evolution of energy system models, through the ex post analysis of both model inputs and outputs using a series of metrics. These metrics help us to understand how models are developed and used and are a powerful tool for effectively targeting future model improvements. The usefulness of model archaeology is demonstrated in a case study examining the UK MARKAL model. We show how model development has been influenced by the interests of the UK government and the research projects funding model development. Despite these influences, there is clear evidence of a strategy to balance model complexity and accuracy when changes are made. We identify some important long-term trends including higher technology capital costs in subsequent model versions. Finally, we discuss how model archaeology can improve the transparency of research model studies. © 2014 The Author(s)
The Business Case for Equality and Diversity: a survey of the academic literature
This report considers the evidence for the business case for equality and diversity in private sector organisations. The aim is not to make the business case, but to assess the current evidence from academic journals and some key practitioner sources
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