28,163 research outputs found
On relativistic discs and rings
Sequences of infinitesimally thin, uniformly rotating, self-gravitating
relativistic discs with internal two-dimensional pressure have been
constructed. It is shown that in weaker relativistic configurations the
sequences undergo a continuous bifurcation from a disc to a ring structure,
while in stronger relativistic cases the sequences terminate at the mass-shed
limit where gravitational forces are exactly balanced by centrifugal forces.Comment: 9 pages, requires mn.sty and epsf.sty, 12 figures included, accepted
by Monthly Notices of the Royal Astronomical Societ
Simulating the Influence of Collaborative Networks on the Structure of Networks of Organizations, Employment Structure, and Organization Value
From the perspective of reindustrialization, it is important to understand
the evolution of the structure of the network of organizations employment
structure, and organization value. Understanding the potential influence of
collaborative networks (CNs) on these aspects may lead to the development of
appropriate economic policies. In this paper, we propose a theoretical approach
to analysis this potential influence, based on a model of dynamic networked
ecosystem of organizations encompassing collaboration relations among
organization, employment mobility, and organization value. A large number of
simulations has been performed to identify factors influencing the structure of
the network of organizations employment structure, and organization value. The
main findings are that 1) the higher the number of members of CNs, the better
the clustering and the shorter the average path length among organizations; 2)
the constitution of CNs does not affect neither the structure of the network of
organizations, nor the employment structure and the organization value.Comment: 10 pages, 1 figure, conference paper at the 14th IFIP Working
Conference on Virtual Enterprises, PRO-VE'13, http://www.pro-ve.org
Muriel Spark and Africa
Muriel Spark’s centenary year has offered opportunities to explore elements of her writing that deserve wider attention. Her time in Africa is vital in this respect. An exhibition at the National Library of Scotland reveals aspects of Spark’s sojourn in Southern Rhodesia and South Africa (https://www.nls.uk/exhibitions/muriel-spark/Africa); critic Eleanor Byrne has begun to map out the impact of time there on her work (https://www.thebottleimp.org.uk/2017/11/go-away-bird-muriel-spark-southern-rhodesia/?print=print); and one of the fruits of the Muriel Spark 100 celebrations is a new book by writer Shane Strachan linking Spark’s African experiences with Scotland (http://www.shanestrachan.com/blog/2018/10/20/nevertheless-muriel-spark-in-bulawayo-murielspark100). Here, with a view to contributing to the discussion around Scotland’s colonial past, I want to look at the afterlife of Africa in Spark’s writings beyond the poems and stories that expressly draw on her experience of that continent
The early years of innovative approaches to youth information and counselling
This chapter focuses on the innovative services set up for the specific purpose of giving social support to young people by means of information and counselling in youth information and counselling services. These innovative services originated roughly from the mid sixties and developed particularly after 1980
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