150 research outputs found
A Genetic Tuning to Improve the Performance of Fuzzy Rule-Based Classification Systems with Interval-Valued Fuzzy Sets: Degree of Ignorance and Lateral Position
Fuzzy Rule-Based Systems are appropriate tools to deal with classification problems due to their good properties. However, they can suffer a lack of system accuracy as a result of the uncertainty inherent in the definition of the membership functions and the limitation of the homogeneous distribution of the linguistic labels.
The aim of the paper is to improve the performance of Fuzzy Rule-Based Classification Systems by means of the Theory of Interval-Valued Fuzzy Sets and a post-processing genetic tuning step. In order to build the Interval-Valued Fuzzy Sets we define a new function called weak ignorance for modeling the uncertainty associated with the definition of the membership functions. Next, we adapt the fuzzy partitions to the problem in an optimal way through a cooperative evolutionary tuning in which we handle both the degree of ignorance and the lateral position (based on the 2-tuples fuzzy linguistic representation) of the linguistic labels.
The experimental study is carried out over a large collection of data-sets and it is supported by a statistical analysis. Our results show empirically that the use of our methodology outperforms the initial Fuzzy Rule-Based Classification System. The application of our cooperative tuning enhances the results provided by the use of the isolated tuning approaches and also improves the behavior of the genetic tuning based on the 3-tuples fuzzy linguistic representation.Spanish Government
TIN2008-06681-C06-01
TIN2010-1505
A WFI survey in the Chamaeleon II dark cloud
We present the results of an optical multi-band survey for low-mass Pre-Main
Sequence (PMS) stars and young Brown Dwarfs (BDs) in the Chamaeleon II (Cha II)
dark cloud. This survey constitutes the complementary optical data to the c2d
Spitzer Legacy survey in Cha II.
Using the Wide-Field Imager (WFI) at the ESO 2.2m telescope, we surveyed a
sky area of about 1.75 square degrees in Cha II. The region was observed in the
Rc, Ic and z broad-bands, in H-alpha and in two medium-band filters centered at
856 and 914 nm. We select PMS star and young BD candidates using
colour-magnitude diagrams (CMDs) and theoretical isochrones reproduced ad-hoc
for the WFI at the ESO2.2m telescope system. The selection criteria are also
reinforced by using the previously known PMS stars in Cha II to define the PMS
locus on the CMDs and by investigating the infrared (IR) colours of the
candidates. By exploiting the WFI intermediate-band photometry we also estimate
the effective temperature and the level of H-alpha emission of the candidates.
Our survey, which is one of the largest and deepest optical surveys conducted
so far in Cha II, recovered the majority of the PMS stars and 10 member
candidates of the cloud from previous IR surveys. In addition, the survey
revealed 10 new potential members. From our photometric characterisation, we
estimate that some 50% of the 20 candidates will result in true Cha II members.
Based on our temperature estimates, we conclude that several of these objects
are expected to be sub-stellar and give a first estimate of the fraction of
sub-stellar objects.Comment: 26 pages, 18 figure
Sensorimotor tongue evaluation and rehabilitation in patients with sleep-disordered breathing: a novel approach
We acknowledge the work of Professor O’Connor-Reina
who designed
and produced the Airway Gym® app for his patients and
whose work was central to this research.Study objectives: To evaluate tone, apraxia and stereognosis dysfunctions in patients
with SDB compared with healthy controls, and to monitor the effectiveness of
Airway Gym® as an easy-to-
use
myofunctional therapy (MT) modality in terms of the
tongue's motor and sensory responses, comparing results before and after therapy.
Methods: This was a prospective, non-randomised
pilot study of 25 patients with
moderate to severe obstructive sleep apnoea-hypopnoea
syndrome (OSAHS), 25 patients
with primary snoring (PS) and 20 healthy controls. Qualitative and quantitative
instruments—Iowa
Oral Performance Instrument (IOPI), lingual apraxia and stereognosis
tests were used to assess tongue sensorimotor function.
Results: 22 patients with PS, 21 with OSAHS and all 20 controls ended the therapy.
In OSAHS, the Epworth Sleepiness Scale score decreased from 16 ± 7.3 to 12 ± 4.5
after therapy (p = 0.53). In PS and OSAHS groups, the IOPI scores increased significantly.
These measures did not change significantly in the controls. Lingual apraxia
testing showed that controls performed all the manoeuvres, whereas PS 5.6 ± 1.4
and OSAHS 4.5 ± 1.9 (p = 0.14). In the stereognosis test, the mean number of figures
recognised was 2.6 ± 2.2 in OSAHS, 3.3±1.2 in PS and 5.7±0.9 in control group
(p < 0.05). Patients with OSAHS recognised circles and ovals less often.
Conclusion: Using the Airway Gym®app produced improvements in sensorimotor
tongue function in patients with SDB, due to continuous stimulation of the brain
based on proprioceptive training required to localise responses when doing the
exercises
Accretion-ejection connection in the young brown dwarf candidate ISO-Cha1 217
As the number of observed brown dwarf outflows is growing it is important to
investigate how these outflows compare to the well studied jets from young
stellar objects. A key point of comparison is the relationship between outflow
and accretion activity and in particular the ratio between the mass outflow and
accretion rates (/). The brown dwarf candidate
ISO-ChaI 217 was discovered by our group, as part of a spectro-astrometric
study of brown dwarfs, to be driving an asymmetric outflow with the
blue-shifted lobe having a position angle of 20. The aim here
is to further investigate the properties of ISO-ChaI 217, the morphology and
kinematics of its outflow, and to better constrain
(/). The outflow is spatially resolved in the
lines and is detected out to 1\farcs6
in the blue-shifted lobe and ~ 1" in the red-shifted lobe. The asymmetry
between the two lobes is confirmed although the velocity asymmetry is less
pronounced with respect to our previous study. Using thirteen different
accretion tracers we measure log() [M/yr]= -10.6
0.4. As it was not possible to measure the effect of extinction on the ISO-ChaI
217 outflow was derived for a range of values of A, up to
a value of A = 2.5 mag estimated for the source extinction. The logarithm
of the mass outflow () was estimated in the range -11.7 to -11.1
for both jets combined. Thus / [\Msun/yr] lies
below the maximum value predicted by magneto-centrifugal jet launching models.
Finally, both model fitting of the Balmer decrements and spectro-astrometric
analysis of the H line show that the bulk of the H I emission comes
from the accretion flow.Comment: accepted by Astronomy & Astrophysic
MRQAR: A generic MapReduce framework to discover quantitative association rules in big data problems
Many algorithms have emerged to address the discovery of quantitative association rules from datasets in the last years. However, this task is becoming a challenge because the processing power of most existing techniques is not enough to handle the large amount of data generated nowadays. These vast amounts of data are known as Big Data. A number of previous studies have been focused on mining boolean or nominal association rules from Big Data problems, nevertheless, the data in real-world applications usually consist of quantitative values and designing data mining algorithms able to extract quantitative association rules presents a challenge to workers in this research field. In spite of the fact that we can find classical methods to discover boolean or nominal association rules in the most well-known repositories of Big Data algorithms, such repositories do not provide methods to discover quantitative association rules. Indeed, no methodologies have been proposed in the literature without prior discretization in Big Data. Hence, this work proposes MRQAR, a new generic parallel framework to discover quantitative association rules in large amounts of data, designed following the MapReduce paradigm using Apache Spark. MRQAR performs an incremental learning able to run any sequential quantitative association rule algorithm in Big Data problems without needing to redesign such algorithms. As a case study, we have integrated the multiobjective evolutionary algorithm MOPNAR into MRQAR to validate the generic MapReduce framework proposed in this work. The results obtained in the experimental study performed on five Big Data problems prove the capability of MRQAR to obtain reduced set of high quality rules in reasonable time.Ministerio de Economía y Competitividad TIN2017-89517-PMinisterio de Economía y Competitividad TIN2014-55894-C2-1-RMinisterio de Economía y Competitividad TIN2017-88209-C2-2-
A label free disposable device for rapid isolation of rare tumor cells from blood by ultrasounds
The use of blood samples as liquid biopsy is a label-free method for cancer diagnosis that offers benefits over traditional invasive biopsy techniques. Cell sorting by acoustic waves offers a means to separate rare cells from blood samples based on their physical properties in a label-free, contactless and biocompatible manner. Herein, we describe a flow-through separation approach that provides an efficient separation of tumor cells (TCs) from white blood cells (WBCs) in a microfluidic device, "THINUS-Chip" (Thin-Ultrasonic-Separator-Chip), actuated by ultrasounds. We introduce for the first time the concept of plate acoustic waves (PAW) applied to acoustophoresis as a new strategy. It lies in the geometrical chip design: different to other microseparators based on either bulk acoustic waves (BAW) or surface waves (SAW, SSAW and tSAW), it allows the use of polymeric materials without restrictions in the frequency of work. We demonstrate its ability to perform high-throughput isolation of TCs from WBCs, allowing a recovery rate of 84%±8% of TCs with a purity higher than 80% and combined viability of 85% at a flow rate of 80 µL/min (4.8 mL/h). The THINUS-Chip performs cell fractionation with low-cost manufacturing processes, opening the door to possible easy printing fabrication
Búsqueda de single nucleotide polymorphisms en el gen dgat1 (diacilglicerol o-aciltransferasa 1) vinculado a la infiltración grasa: resultados preliminares en razas bovinas autóctonas
Chemical and mechanical stability of air annealed cathodic arc evaporated CrAlON coatings
This study reports the synthesis and characterization of ternary Cr-Al-O and quaternary Cr-Al-O-N coatings deposited by cathodic arc physical vapour deposition, for various nitrogen and oxygen mass flow ratios during the growth process. The composition, microstructure, indentation hardness and modulus of the films have been characterized by scanning electron microscopy, electron probe micro-analysis, X-ray diffraction, and nanoindentation techniques. The evolution of the microstructure and mechanical properties of the coatings after ambient air annealing from 800 °C up to 1100 °C have been investigated. As the oxygen to nitrogen mass flow increases, the as-deposited coatings exhibit lower hardness, higher roughness, lower crystallinity and a more marked columnar structure. At oxygen to nitrogen mass flow ratios bigger than 10/90, the coatings exhibit a stoichiometry of the type (CrAl)2+εO3−ε. Only the coatings with an oxygen to nitrogen mass flow ratio smaller than 10/90 retained nitrogen in their compositions. In all cases, the coatings developed a cubic fcc lattice structure. After annealing at 1100 °C the resulting microstructure showed a clear dependency upon the initial composition of the films. The evolution of the microstructure during the high temperature tests, as well as the analysis of the nanoindentation hardness, composition and thickness also provided valuable information about the combined effects of the thermal stability and the oxidation of the deposited coatings
A Device for Scheduling Irrigation in Fruit Tree Orchards from Sap Flow Readings
Abstract The aim of this work was to design and test a controller (CRP) able to calculate the irrigation dose automatically, suitable for high frequency irrigation in fruit tree orchards. The device consisted of three (replicates) measuring units (MU), a control unit (CU) and a pump and electrovalve controller (PEC). The MUs collected information on the transpiration (E p ) dynamics within the orchard, with the compensation heat-pulse method. Each MU made sap flow readings in one normally-irrigated (NI) tree and in one over-irrigated (OI) tree used for reference. The time course of the E pNI /E pOI ratio was used by the CU for calculating the irrigation dose (ID) daily. The system was programmed to apply a deficit irrigation in which the trees were bound to use part of the readily available water in the soil. Laboratory tests showed a high performance of the CRP for amplifying and filtering output signals from the sap flow probes. The field test showed the CRP was able to collect and handle sap flow data, to calculate ID according to the design algorithm, and to control the pump and electrovalve for supplying the desired ID to the experimental plot. Whether the use of the CRP means an improvement on irrigation scheduling, as compared to standard methods, was not evaluated in this work
Asociación entre polimorfismos genéticos de los genes de la µ-calpaína, la m-calpaína y la calpastatina y actividad enzimática en el sistema calpaína-calpastatina en la raza retinta: primeros resultados
Ministerio de Agricultura, Pesca y Alimentació
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