3,603 research outputs found
Coins falling in water
When a coin falls in water, its trajectory is one of four types determined by
its dimensionless moment of inertia and Reynolds number Re: (A)
steady; (B) fluttering; (C) chaotic; or (D) tumbling. The dynamics induced by
the interaction of the water with the surface of the coin, however, makes the
exact landing site difficult to predict a priori. Here, we describe a carefully
designed experiment in which a coin is dropped repeatedly in water, so that we
can determine the probability density functions (pdf) associated with the
landing positions for each of the four trajectory types, all of which are
radially symmetric about the center-drop line. In the case of the steady mode,
the pdf is approximately Gaussian distributed, with variances that are small,
indicating that the coin is most likely to land at the center, right below the
point it is dropped from. For the other falling modes, the center is one of the
least likely landing sites. Indeed, the pdf's of the fluttering, chaotic and
tumbling modes are characterized by a "dip" around the center. For the tumbling
mode, the pdf is a ring configuration about the center-line, with a ring width
that depends on the dimensionless parameters and Re and height from
which the coin is dropped. For the chaotic mode, the pdf is generally a
broadband distribution spread out radially symmetrically about the center-line.
For the steady and fluttering modes, the coin never flips, so the coin lands
with the same side up as was dropped. For the chaotic mode, the probability of
heads or tails is close to 0.5. In the case of the tumbling mode, the
probability of heads or tails based on the height of the drop which determines
whether the coin flips an even or odd number of times during descent
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East Kent maternity services review
Background to Report: This document presents the results of an analysis of the responses to the formal public consultation on east Kent maternity services which took place over a 14 week period from 14th October 2011 to 20th January 2012. The consultation was conducted by NHS Kent and Medway, and the data gathered was analysed independently by the Centre for Nursing and Healthcare Research at the University of Greenwich
An Analysis of the Behavior of the Risk Premium in the German Deutschemark Forward Market: A Comparison of Pre- and Post-German Reunification of 1990 Exchange Rates
The German reunification of 1990 and the methods of economic integration exerted considerable pressure on both the German economy and the deutschemark. This thesis addresses the issue that the reunification undermined the stability of the deutschemark, detectable through a change in the implied risk premium. Emphasis is placed on the forward deutschemark in the context of interest rate parity in order to detect a change in the implied risk premium. By using three month U.S. and German bank Certificate of Deposit rates as the basis for the IRP calculations, a considerable shift in this implied risk premium was detected and attributed to a riskier deutschemark
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Evaluation of the ‘Rotational Post - End of Life Care, Cancer Care and Care of the Elderly’ Project
In 2017, South London Hospices Education Collaborative approached the University of Greenwich to conduct an evaluation of the first year of the ‘Rotational Post - End of Life Care, Cancer and Care of the Elderly’ Project. The original project had offered newly-qualified and developing band 5 nurses (within 3 years of qualifying) the opportunity to work in three care settings over the course of a year (4 month blocks) with support from palliative care professionals, managers and the project lead. The nurses also undertook a postgraduate module in palliative care or a relevant topic. The identified care settings were - specialist inpatient palliative care in hospices, oncology wards, and care of the frail elderly in intermediate care settings or similar community provision.
The evaluation began in September 2017 and its aim was to evaluate the perceived and felt impact of the project as assessed by the nurses who took part and the key staff (stakeholders) in the host organisations. Qualitative focus groups (with participating nursing staff) and interviews (with stakeholders) were conducted and analysed to assess the perceived impact the project had on stakeholders’ and participating nurses’ perceptions and experiences of the rotation project, and whether the project had, according to participants’ accounts, attained its original aims.
The data presented in this report are the outcome of gathering and analysing data from two focus groups (N = 7 & 5 participants) with nurses who rotated during the project, and seven interviews with stakeholder participants who rotated their own, and hosted other organisations’, staff
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