25,162 research outputs found
Dominance-based Rough Set Approach, basic ideas and main trends
Dominance-based Rough Approach (DRSA) has been proposed as a machine learning
and knowledge discovery methodology to handle Multiple Criteria Decision Aiding
(MCDA). Due to its capacity of asking the decision maker (DM) for simple
preference information and supplying easily understandable and explainable
recommendations, DRSA gained much interest during the years and it is now one
of the most appreciated MCDA approaches. In fact, it has been applied also
beyond MCDA domain, as a general knowledge discovery and data mining
methodology for the analysis of monotonic (and also non-monotonic) data. In
this contribution, we recall the basic principles and the main concepts of
DRSA, with a general overview of its developments and software. We present also
a historical reconstruction of the genesis of the methodology, with a specific
focus on the contribution of Roman S{\l}owi\'nski.Comment: This research was partially supported by TAILOR, a project funded by
European Union (EU) Horizon 2020 research and innovation programme under GA
No 952215. This submission is a preprint of a book chapter accepted by
Springer, with very few minor differences of just technical natur
Azimuthal Spin Asymmetries of Pion Electroproduction
Azimuthal spin asymmetries, both for charged and neutral pion production in
semi-inclusive deep inelastic scattering of unpolarized charged lepton beams on
longitudinally and transversely polarized nucleon targets, are analyzed and
calculated. Various assumptions and approximations in the quark distributions
and fragmentation functions often used in these calculations are studied in
detail. It is found that different approaches to the distribution and
fragmentation functions may lead to quite different predictions on the
azimuthal asymmetries measured in the HERMES experiments, thus their effects
should be taken into account before using the available data as a measurement
of quark transversity distributions. It is also found that the unfavored quark
to pion fragmentation functions must be taken into account for
production from a proton target, although they can be neglected for and
production. Pion production from a proton target is suitable to study
the quark transversity distribution, whereas a combination of pion
production from both proton and neutron targets can measure the flavor
structure of quark transversity distributions.Comment: 31 latex pages, 13 figure, to appear in PR
Attribute Equilibrium Dominance Reduction Accelerator (DCCAEDR) Based on Distributed Coevolutionary Cloud and Its Application in Medical Records
© 2013 IEEE. Aimed at the tremendous challenge of attribute reduction for big data mining and knowledge discovery, we propose a new attribute equilibrium dominance reduction accelerator (DCCAEDR) based on the distributed coevolutionary cloud model. First, the framework of N-populations distributed coevolutionary MapReduce model is designed to divide the entire population into N subpopulations, sharing the reward of different subpopulations' solutions under a MapReduce cloud mechanism. Because the adaptive balancing between exploration and exploitation can be achieved in a better way, the reduction performance is guaranteed to be the same as those using the whole independent data set. Second, a novel Nash equilibrium dominance strategy of elitists under the N bounded rationality regions is adopted to assist the subpopulations necessary to attain the stable status of Nash equilibrium dominance. This further enhances the accelerator's robustness against complex noise on big data. Third, the approximation parallelism mechanism based on MapReduce is constructed to implement rule reduction by accelerating the computation of attribute equivalence classes. Consequently, the entire attribute reduction set with the equilibrium dominance solution can be achieved. Extensive simulation results have been used to illustrate the effectiveness and robustness of the proposed DCCAEDR accelerator for attribute reduction on big data. Furthermore, the DCCAEDR is applied to solve attribute reduction for traditional Chinese medical records and to segment cortical surfaces of the neonatal brain 3-D-MRI records, and the DCCAEDR shows the superior competitive results, when compared with the representative algorithms
Parameter Selection and Uncertainty Measurement for Variable Precision Probabilistic Rough Set
In this paper, we consider the problem of parameter selection and uncertainty measurement for a variable precision probabilistic rough set. Firstly, within the framework of the variable precision probabilistic rough set model, the relative discernibility of a variable precision rough set in probabilistic approximation space is discussed, and the conditions that make precision parameters α discernible in a variable precision probabilistic rough set are put forward. Concurrently, we consider the lack of predictability of precision parameters in a variable precision probabilistic rough set, and we propose a systematic threshold selection method based on relative discernibility of sets, using the concept of relative discernibility in probabilistic approximation space. Furthermore, a numerical example is applied to test the validity of the proposed method in this paper. Secondly, we discuss the problem of uncertainty measurement for the variable precision probabilistic rough set. The concept of classical fuzzy entropy is introduced into probabilistic approximation space, and the uncertain information that comes from approximation space and the approximated objects is fully considered. Then, an axiomatic approach is established for uncertainty measurement in a variable precision probabilistic rough set, and several related interesting properties are also discussed. Thirdly, we study the attribute reduction for the variable precision probabilistic rough set. The definition of reduction and its characteristic theorems are given for the variable precision probabilistic rough set. The main contribution of this paper is twofold. One is to propose a method of parameter selection for a variable precision probabilistic rough set. Another is to present a new approach to measurement uncertainty and the method of attribute reduction for a variable precision probabilistic rough set
Parameter-Free Calculation of the Solar Proton Fusion Rate in Effective Field Theory
Spurred by the recent complete determination of the weak currents in
two-nucleon systems up to in heavy-baryon chiral perturbation
theory, we carry out a parameter-free calculation of the solar proton fusion
rate in an effective field theory that combines the merits of the standard
nuclear physics method and systematic chiral expansion. Using the tritium
beta-decay rate as an input to fix the only unknown parameter in the effective
Lagrangian, we can evaluate with drastically improved precision the ratio of
the two-body contribution to the well established one-body contribution; the
ratio is determined to be (0.86\pm 0.05) %. This result is essentially
independent of the cutoff parameter for a wide range of its variation (500 MeV
\le \Lambda \le 800 MeV), a feature that substantiates the consistency of the
calculation.Comment: 10 pages. The argument is considerably more sharpened with a reduced
error ba
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