674 research outputs found
An experimental investigation of cyclically, axially loaded piles in sand
Bibliography: leaves 91-93.The research work involved the installation and cyclic load testing of large-scale pressure-grouted, instrumented piles in sand in the laboratory. The major objective of this experimental investigation was to establish the effects of the mean cyclic load level and amplitude on the pile behaviour during cyclic loading. Of particular interest was the study of the skin friction distributions along the pile shafts in order to understand the processes involved. Cyclic loading was limited to one-way loading in load-controlled mode. A literature review showed a lack of experimental data on the cyclic behaviour of large-scale pressure-grouted piles. The results of a number of small model tests in sand are discussed and the major trends of pile performances are highlighted to facilitate comparison of the observations made in this research. It was found that no definite testing procedure for cyclically-loaded piles is common to the various investigations. A research program and procedure of load applications was therefore developed to allow the isolation of the individual influences of the most significant cyclic parameters, the mean cyclic load level and the amplitude. In total 12 piles were installed using the same sand preparation and pile installation techniques. The tests only varied with regard to the applied loading procedur
Simulation Studies of Nanomagnet-Based Architecture
We report a simulation study on interacting ensembles of Co nanomagnets that
can perform basic logic operations and propagate logic signals, where the state
variable is the magnetization direction. Dipole field coupling between
individual nanomagnets drives the logic functionality of the ensemble and
coordinated arrangements of the nanomagnets allow for the logic signal to
propagate in a predictable way. Problems with the integrity of the logic signal
arising from instabilities in the constituent magnetizations are solved by
introducing a biaxial anisotropy term to the Gibbs magnetic free energy of each
nanomagnet. The enhanced stability allows for more complex components of a
logic architecture capable of random combinatorial logic, including horizontal
wires, vertical wires, junctions, fanout nodes, and a novel universal logic
gate. Our simulations define the focus of scaling trends in nanomagnet-based
logic and provide estimates of the energy dissipation and time per nanomagnet
reversal
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Using a prisoner advisory group to develop diversity research in a maximum-security prison: A means of enhancing prisoner participation
YesThis paper addresses groupwork processes with a group of prisoners advising
a research project in a maximum-security prison in England. The research project
(Appreciative Inquiry into the Diversity Strategy of HMP Wakefield. RES-000-22-3441)
was funded by the Economic and Social Research Council (ESRC) and lasted 9 months.
The research explored the experiences of prisoners in diverse minority groupings and the
strategies of the prison to accommodate the complex needs of these groups. The Prisoner
Advisory Group (PAG) was made up of representatives from Black and Minority Ethnic
(BME) prisoners; older prisoners (over 60s); Disabled prisoners (with physical disabilities,
learning difficulties; and mental health problems); Gay, Bi-sexual and Transgender
prisoners; and prisoners affiliated to Faith groups. It met regularly during the research.
The paper considers the forming norming and performing aspects of establishing an
effective participant voice in a prison-based project. It considers the contribution of the
PAG to developing a research strategy that engaged prisoners in the research. It reflects
on the nature of ‘participative research’ in general and whether such research is possible
within a high-security prison environment
Professional boundaries: research report
In 2008 the General Social Care Council (GSCC) published Raising standards: Social work conduct in England 2003-2008. This constituted the GSCC’s first report covering the work undertaken to uphold standards and protect people who use social care services. The GSCC’s analysis revealed that a considerable proportion of conduct cases, some 40%, involved allegations of 'inappropriate relations'. In the light of this finding, and the release by the Council for Healthcare Regulatory Excellence (CHRE) of sexual boundaries guidance for healthcare workers at the beginning of this year (Halter et al, 2009), the GSCC committed itself to exploring the possibility of producing professional boundaries guidance for social workers.
To begin this exploration, the GSCC commissioned a study in early 2009.This is the report of that study. There were two main purposes. First, to establish what professional boundaries1 guidance currently exists for social workers, or for sections of the workforce that includes social workers in the United Kingdom, and the content of any such guidance. Secondly, to identify and discuss a number of other examples of professional boundaries guidance to act as points of reference for the GSCC’s project. The aim was to identify and discuss examples relevant to the GSCC’s project
Evolution and stability of a magnetic vortex in small cylindrical ferromagnetic particle under applied field
The energy of a displaced magnetic vortex in a cylindrical particle made of
isotropic ferromagnetic material (magnetic dot) is calculated taking into
account the magnetic dipolar and the exchange interactions. Under the
simplifying assumption of small dot thickness the closed-form expressions for
the dot energy is written in a non-perturbative way as a function of the
coordinate of the vortex center. Then, the process of losing the stability of
the vortex under the influence of the externally applied magnetic field is
considered. The field destabilizing the vortex as well as the field when the
vortex energy is equal to the energy of a uniformly magnetized state are
calculated and presented as a function of dot geometry. The results (containing
no adjustable parameters) are compared to the recent experiment and are in good
agreement.Comment: 4 pages, 2 figures, RevTe
Confidentiality and public protection: ethical dilemmas in qualitative research with adult male sex offenders
This paper considers the ethical tensions present when engaging in in-depth interviews with convicted sex offenders. Many of the issues described below are similar to those found in other sensitive areas of research. However, confidentiality and public protection are matters that require detailed consideration when the desire to know more about men who have committed serious and harmful offences is set against the possibility of a researcher not disclosing previously unknown sensitive information that relates to the risk of someone being harmed.</p
Coupling and induced depinning of magnetic domain walls in adjacent spin valve nanotracks
The magnetostatic interaction between magnetic domain walls (DWs) in adjacent
nanotracks has been shown to produce strong inter-DW coupling and mutual
pinning. In this paper, we have used electrical measurements of adjacent
spin-valve nanotracks to follow the positions of interacting DWs. We show that
the magnetostatic interaction between DWs causes not only mutual pinning, as
observed till now, but that a travelling DW can also induce the depinning of
DWs in near-by tracks. These effects may have great implications for some
proposed high density magnetic devices (e.g. racetrack memory, DW logic
circuits, or DW-based MRAM).Comment: The following article has been accepted by the Journal of Applied
Physic
Near-field interaction between domain walls in adjacent Permalloy nanowires
The magnetostatic interaction between two oppositely charged transverse
domain walls (DWs)in adjacent Permalloy nanowires is experimentally
demonstrated. The dependence of the pinning strength on wire separation is
investigated for distances between 13 and 125 nm, and depinning fields up to 93
Oe are measured. The results can be described fully by considering the
interaction between the full complex distribution of magnetic charge within
rigid, isolated DWs. This suggests the DW internal structure is not appreciably
disturbed by the pinning potential, and that they remain rigid although the
pinning strength is significant. This work demonstrates the possibility of
non-contact DW trapping without DW perturbation and full continuous flexibility
of the pinning potential type and strength. The consequence of the interaction
on DW based data storage schemes is evaluated.Comment: 4 pages, 4 figures, 1 page supplimentary material (supporting.ps
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