17 research outputs found
A quantitative taxonomy of human hand grasps
Background: A proper modeling of human grasping and of hand movements is fundamental for robotics,
prosthetics, physiology and rehabilitation. The taxonomies of hand grasps that have been proposed in scientific
literature so far are based on qualitative analyses of the movements and thus they are usually not quantitatively
justified.
Methods: This paper presents to the best of our knowledge the first quantitative taxonomy of hand grasps based on
biomedical data measurements. The taxonomy is based on electromyography and kinematic data recorded from 40
healthy subjects performing 20 unique hand grasps. For each subject, a set of hierarchical trees are computed for
several signal features. Afterwards, the trees are combined, first into modality-specific (i.e. muscular and kinematic)
taxonomies of hand grasps and then into a general quantitative taxonomy of hand movements. The modality-specific
taxonomies provide similar results despite describing different parameters of hand movements, one being muscular
and the other kinematic.
Results: The general taxonomy merges the kinematic and muscular description into a comprehensive hierarchical
structure. The obtained results clarify what has been proposed in the literature so far and they partially confirm the
qualitative parameters used to create previous taxonomies of hand grasps. According to the results, hand movements
can be divided into five movement categories defined based on the overall grasp shape, finger positioning and
muscular activation. Part of the results appears qualitatively in accordance with previous results describing kinematic
hand grasping synergies.
Conclusions: The taxonomy of hand grasps proposed in this paper clarifies with quantitative measurements what
has been proposed in the field on a qualitative basis, thus having a potential impact on several scientific fields
Systems Biology in ELIXIR: modelling in the spotlight
In this white paper, we describe the founding of a new ELIXIR Community - the Systems Biology Community - and its proposed future contributions to both ELIXIR and the broader community of systems biologists in Europe and worldwide. The Community believes that the infrastructure aspects of systems biology - databases, (modelling) tools and standards development, as well as training and access to cloud infrastructure - are not only appropriate components of the ELIXIR infrastructure, but will prove key components of ELIXIR\u27s future support of advanced biological applications and personalised medicine. By way of a series of meetings, the Community identified seven key areas for its future activities, reflecting both future needs and previous and current activities within ELIXIR Platforms and Communities. These are: overcoming barriers to the wider uptake of systems biology; linking new and existing data to systems biology models; interoperability of systems biology resources; further development and embedding of systems medicine; provisioning of modelling as a service; building and coordinating capacity building and training resources; and supporting industrial embedding of systems biology. A set of objectives for the Community has been identified under four main headline areas: Standardisation and Interoperability, Technology, Capacity Building and Training, and Industrial Embedding. These are grouped into short-term (3-year), mid-term (6-year) and long-term (10-year) objectives
Information Retrieval Meets Information Visualization. PROMISE Winter School 2012. Revised Tutorial Lectures.
The research domains information retrieval and information visualization have always been independent from each other. However, they have the potential to be mutually beneficial. With this in mind, a winter school was organized in Zinal, Switzerland, in January 2012, within the context of the EU-funded research project PROMISE (Participative Research Laboratory for Multimedia and Multilingual Information Systems Evaluation). PROMISE aims at advancing the experimental evaluation of complex multimedia and multilingual information systems in order to support individuals, commercial entities, and communities who design, develop, employ, and improve such complex systems. The overall goal of PROMISE is to deliver a unified environment collecting data, knowledge, tools, and methodologies, and to help the user community involved in experimental evaluation
Comparison of six electromyography acquisition setups on hand movement classification tasks
Hand prostheses controlled by surface electromyography are promising due to the non-invasive approach and the control capabilities offered by machine learning. Nevertheless, dexterous prostheses are still scarcely spread due to control difficulties, low robustness and often prohibitive costs. Several sEMG acquisition setups are now available, ranging in terms of costs between a few hundred and several thousand dollars. The objective of this paper is the relative comparison of six acquisition setups on an identical hand movement classification task, in order to help the researchers to choose the proper acquisition setup for their requirements. The acquisition setups are based on four different sEMG electrodes (including Otto Bock, Delsys Trigno, Cometa Wave + Dormo ECG and two Thalmic Myo armbands) and they were used to record more than 50 hand movements from intact subjects with a standardized acquisition protocol. The relative performance of the six sEMG acquisition setups is compared on 41 identical hand movements with a standardized feature extraction and data analysis pipeline aimed at performing hand movement classification. Comparable classification results are obtained with three acquisition setups including the Delsys Trigno, the Cometa Wave and the affordable setup composed of two Myo armbands. The results suggest that practical sEMG tests can be performed even when costs are relevant (e.g. in small laboratories, developing countries or use by children). All the presented datasets can be used for offline tests and their quality can easily be compared as the data sets are publicly available
Orbital and spectral characterization of the benchmark T-type brown dwarf HD 19467B
Context. Detecting and characterizing substellar companions for which the
luminosity, mass, and age can be determined independently is of utter
importance to test and calibrate the evolutionary models due to uncertainties
in their formation mechanisms. HD 19467 is a bright and nearby star hosting a
cool brown dwarf companion detected with RV and imaging, making it a valuable
object for such studies. Aims. We aim to further characterize the orbital,
spectral, and physical properties of the HD 19467 system. Methods. We present
new high-contrast imaging data with the SPHERE and NaCo instruments. We also
analyze archival data from HARPS, NaCo, HIRES, UVES, and ASAS. We also use
proper motion data of the star from Hipparcos and Gaia. Results. We refine the
properties of the host star and derive an age of 8.0 Gyr based
on isochrones, gyrochronology, and chemical and kinematic arguments. This
estimate is slightly younger than previous estimates of ~9-11 Gyr. No orbital
curvature is seen in the current imaging, RV, and astrometric data. From a
joint fit of the data, we refine the orbital parameters for HD 19467B: period
398 yr, inclination 129.8 deg, eccentricity
0.560.09, longitude of the ascending node 134.84.5 deg, and argument
of the periastron 64.2 deg. We assess a dynamical mass of
74 MJ. The fit with atmospheric models of the spectrophotometric
data of HD 19467B indicates an atmosphere without clouds or with very thin
clouds, an effective temperature of 1042 K, and a large surface
gravity of 5.34 dex. The comparison to model predictions of
the bolometric luminosity and dynamical mass of HD 19467B, assuming our system
age estimate, indicates a better agreement with the Burrows et al. models;
whereas the other evolutionary models used tend to underestimate its cooling
rate.Comment: Accepted for publication in A&A, 25 pages, 23 figures, 9 tables.
Abstract slightly abridged to match arXiv requirements. Updated after
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