18,425 research outputs found
Renormalized stress tensor of a quantized massless scalar field in warped cosmological braneworld background
Energy momentum tensor of a conformally coupled quantum scalar field in five
dimensional warped cosmological spacetimes is studied. We look at situations
where the four dimensional part represents a cosmological thick brane and the
scale of the extra dimension is time dependent. Renormalization of the
components of the energy momentum tensor is achieved using adiabatic
regularization method. The resulting energy and pressure densities explicitly
show the effects of warping and the dynamic extra dimension on the created
matter. We discussed how the created matter may accumulate to form thick branes
along the extra dimension.Comment: 17+1 preprint pages. To appear in EPJ
A Human Rights Based Approach to Refugees: A Look at the Syrian Refugee Crisis and the Responses from Germany and the United States
Power Quality (PQ) has gained a lot of importance in the last decade. Several solutions to power quality problems have been proposed and developed. With the advent of solid state technology and power electronics in the power system protection devices, faster switching is achievable. In order to control and minimize the power quality problems which occur in extremely short times of less than 100ms, the need arises for a selection of devices that can switch faster than today. Also, the economic losses that occur in the network due to the power quality problems increase the incentive to transform the existing devices into faster and e fficient devices. This transformation can be seen as valuable from both a technical and economical point of view to the distribution networks today where a large number of customers are connected. However, in order to interpret the value these fast switching devices render to the distribution network a prior study is required. This thesis presents a picture of the devices that can be suitable for fast switching in today’s distribution network, and how to determine their value to the distribution network. Further it summarizes the research work related to this field. The description of the devices and technical aspects is presented first. A literature review of proposed devices is given. The technical aspects of power quality and its problems is described. An approach to estimate the value of the fast switching devices is detailed from different literature. The study shows that fast switching devices can be worthy to invest in when seen from a distribution network’s perspective provided that different technical aspects are taken into account
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Disciplinary departures and discipline formation: The institutional rationale
This paper analyses the institutional relationship between Creative Writing and Literary Studies, with their erstwhile close association and current drift towards disciplinary separation in view. It is in three parts. The first outlines some histories of the academic discipline of Creative Writing in the university. The second examines what’s involved for Creative Writing in discipline formation in the university, and touches on the role played by professional associations (with a particular emphasis on the case of NAWE in Britain). The third part comments on recent moves towards developing Creative Writing Studies
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