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GRIDCC: Real-time workflow system
The Grid is a concept which allows the sharing of resources between distributed communities, allowing each to progress towards potentially different goals. As adoption of the Grid increases so are the activities that people wish to conduct through it. The GRIDCC project is a European Union funded project addressing the issues of integrating instruments into the Grid. This increases the requirement of workflows and Quality of Service upon these workflows as many of these instruments have real-time requirements. In this paper we present the workflow management service within the GRIDCC project which is tasked with optimising the workflows and ensuring that they meet the pre-defined QoS requirements specified upon them
The use of underactuation in prosthetic grasping
Underactuation as a method of driving prosthetic hands has a long history. The pragmatic requirements of such a device to be light enough to be worn and used regularly have meant that any multi degree of freedom prosthetic hand must have fewer actuators than the usable degrees of freedom. Aesthetics ensures that while the hand needs five fingers, five actuators have considerable mass, and only in recent years has it even been possible to construct a practical anthropomorphic hand with five motors. Thus there is an important trade off as to which fingers are driven, and which joints on which fingers are actuated, and how the forces are distributed to create a functional device. This paper outlines some of the historical solutions created for this problem and includes those designs of recent years that are now beginning to be used in the commercial environment. <br><br> <i>This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.</i>
Skill assessment in upper limb myoelectric prosthesis users: Validation of a clinically feasible method for characterising upper limb temporal and amplitude variability during the performance of functional tasks
Upper limb myoelectric prostheses remain challenging to use and are often abandoned. A proficient user must be able to plan/execute arm movements while activating the residual muscle(s), accounting for delays and unpredictability in prosthesis response. There is no validated, low cost measure of skill in performing such actions. Trial-trial variability of joint angle trajectories measured during functional task performance, linearly normalised by time, shows promise. However, linear normalisation of time introduces errors, and expensive camera systems are required for joint angle measurements.
This study investigated whether trial-trial variability, assessed using dynamic time warping (DTW)of limb segment acceleration measured during functional task performance, is a valid measure of user skill. Temporal and amplitude variability of forearm accelerations were determined in 1) seven myoelectric prosthesis users and six anatomically-intact controls and 2) seven anatomically-intact subjects learning to use a prosthesis simulator over repeated sessions.
1: temporal variability showed clear group differences (p<0.05). 2: temporal variability considerably increased on first use of a prosthesis simulator, then declined with training (both p<0.05). Amplitude variability showed less obvious differences. Analysing forearm accelerations using DTW appears to be a valid low-cost method for quantifying movement quality of upper limb prosthesis use during goal-oriented task performance
Report of the working group on the measurement of triple gauge boson couplings
The working group discussed several aspects of triple gauge coupling analysis viewed in the light of experiences with the first high energy data recorded at energies above the W pair threshold. Some analysis methods were reviewed briefly, and consideration given to better ways of characterising the data. The measurement of CP violating parameters was discussed. Results were prepared to further quantify the precision attainable on anaomalous couplings in the four-quark channel using jet-charge methods, and finally the trade off between maximum LEP energy-vs-luminosity was quantified.The working group discussed several aspects of triple gauge coupling analysis viewed in the light of experiences with the first high energy data recorded at energies above the W pair threshold. Some analysis methods were reviewed briefly, and consideration given to better ways of characterising the data. The measurement of CP violating parameters was discussed. Results were prepared to further quantify the precision attainable on anaomalous couplings in the four-quark channel using jet-charge methods, and finally the trade off between maximum LEP energy-vs-luminosity was quantified
Upper- and lower-limb amputees show reduced levels of eeriness for images of prosthetic hands
The uncanny phenomenon describes the feeling of unease associated with seeing an image which is close to appearing human. Prosthetic hands in particular are well-known to induce this effect. Little is known, however, about this phenomenon from the viewpoint of prosthesis users. We studied perceptions of eeriness and human-likeness for images of different types of mechanical, cosmetic,
and anatomical hands in upper-limb prosthesis users (n=9), lower-limb prosthesis users (n=10), prosthetists (n=16), control participants with no prosthetic training (n=20), and control participants who were trained to use a myoelectric prosthetic hand simulator (n=23). Both the upper- and lowerlimb prosthesis user groups showed a reduced uncanny phenomenon (i.e., significantly lower levels of eeriness) for cosmetic prosthetic hands compared to the other groups, with no concomitant reduction in how these stimuli were rated in terms of human-likeness. However, a similar effect was found neither for prosthetists with prolonged visual experience of prosthetic hands, nor for the group with short-term training with the simulator. These findings in the prosthesis users therefore seem likely to be related to limb absence or prolonged experience with prostheses
Visuomotor behaviours when using a myoelectric prosthesis
Background
A recent study showed that the gaze patterns of amputee users of myoelectric
prostheses differ markedly from those seen in anatomically intact subjects. Gaze
behaviour is a promising outcome measures for prosthesis designers, as it appears to
reflect the strategies adopted by amputees to compensate for the absence of
proprioceptive feedback and uncertainty/delays in the control system, factors believed
to be central to the difficulty in using prostheses. The primary aim of our study was to
characterise visuomotor behaviours over learning to use a trans-radial myoelectric
prosthesis. Secondly, as there are logistical advantages to using anatomically intact
subjects in prosthesis evaluation studies, we investigated similarities in visuomotor
behaviours between anatomically intact users of a trans-radial prosthesis simulator
and experienced trans-radial myoelectric prosthesis users.
Methods
In part 1 of the study, we investigated visuomotor behaviours during performance of a
functional task (reaching, grasping and manipulating a carton) in a group of seven
anatomically intact subjects over learning to use a trans-radial myoelectric prosthesis
simulator (Dataset 1). Secondly, we compared their patterns of visuomotor behaviour
with those of four experienced trans-radial myoelectric prosthesis users (Dataset 2).
We recorded task movement time, performance on the SHAP test of hand function
and gaze behaviour.
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Results
Dataset 1 showed that while reaching and grasping the object, anatomically intact
subjects using the prosthesis simulator devoted around 90% of their visual attention to
either the hand or the area of the object to be grasped. This pattern of behaviour did
not change with training, and similar patterns were seen in Dataset 2. Anatomically
intact subjects exhibited significant increases in task duration at their first attempts to
use the prosthesis simulator. At the end of training, the values had decreased and were
similar to those seen in Dataset 2.
Conclusions
The study provides the first functional description of the gaze behaviours seen during
use of a myoelectric prosthesis. Gaze behaviours were found to be relatively
insensitive to practice. In addition, encouraging similarities were seen between the
amputee group and the prosthesis simulator group
Interim Design Report
The International Design Study for the Neutrino Factory (the IDS-NF) was
established by the community at the ninth "International Workshop on Neutrino
Factories, super-beams, and beta- beams" which was held in Okayama in August
2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for
the facility on the timescale of 2012/13. In addition, the mandate for the
study [3] requires an Interim Design Report to be delivered midway through the
project as a step on the way to the RDR. This document, the IDR, has two
functions: it marks the point in the IDS-NF at which the emphasis turns to the
engineering studies required to deliver the RDR and it documents baseline
concepts for the accelerator complex, the neutrino detectors, and the
instrumentation systems. The IDS-NF is, in essence, a site-independent study.
Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific
issues to be addressed in the cost analysis that will be presented in the RDR.
The choice of example sites should not be interpreted as implying a preferred
choice of site for the facility
Experimental Status of Neutrino Physics
After a fascinating phase of discoveries, neutrino physics still has a few
mysteries such as the absolute mass scale, the mass hierarchy, the existence of
CP violation in the lepton sector and the existence of right-handed neutrinos.
It is also entering a phase of precision measurements. This is what motivates
the NUFACT 11 conference which prepares the future of long baseline neutrino
experiments. In this paper, we report the status of experimental neutrino
physics. We focus mainly on absolute mass measurements, oscillation parameters
and future plans for oscillation experiments
Search for Yukawa Production of a Light Neutral Higgs Boson at LEP
Within a Two-Higgs-Doublet Model (2HDM) a search for a light Higgs boson in
the mass range of 4-12 GeV has been performed in the Yukawa process e+e- -> b
bbar A/h -> b bbar tau+tau-, using the data collected by the OPAL detector at
LEP between 1992 and 1995 in e+e- collisions at about 91 GeV centre-of-mass
energy. A likelihood selection is applied to separate background and signal.
The number of observed events is in good agreement with the expected
background. Within a CP-conserving 2HDM type II model the cross-section for
Yukawa production depends on xiAd = |tan beta| and xihd = |sin alpha/cos beta|
for the production of the CP-odd A and the CP-even h, respectively, where tan
beta is the ratio of the vacuum expectation values of the Higgs doublets and
alpha is the mixing angle between the neutral CP-even Higgs bosons. From our
data 95% C.L. upper limits are derived for xiAd within the range of 8.5 to 13.6
and for xihd between 8.2 to 13.7, depending on the mass of the Higgs boson,
assuming a branching fraction into tau+tau- of 100%. An interpretation of the
limits within a 2HDM type II model with Standard Model particle content is
given. These results impose constraints on several models that have been
proposed to explain the recent BNL measurement of the muon anomalous magnetic
moment.Comment: 24 pages, 9 figures, Submitted to Euro. Phys. J.
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