714 research outputs found
Non-empirical shape dynamics of heavy nuclei with multi-task deep learning
A microscopic description of nuclear fission represents one of the most
challenging problems in nuclear theory. While phenomenological coordinates,
such as multipole moments, have often been employed to describe fission, it is
not obvious whether these parameters fully reflect the shape dynamics of
interest. We here propose a novel method to extract collective coordinates,
which are free from phenomenology, based on multi-task deep learning in
conjunction with a density functional theory (DFT). To this end, we first
introduce randomly generated external fields to a Skyrme-EDF and construct a
set of nuclear number densities and binding energies for deformed states of
U around the ground state. By training a neural network on such
dataset with a combination of an autoencoder and supervised learning, we
successfully identify a two-dimensional latent variables that accurately
reproduce both the energies and the densities of the original Skyrme-EDF
calculations, within a mean absolute error of 113 keV for the energies. In
contrast, when multipole moments are used as latent variables for training in
constructing the decoders, we find that the training data for the binding
energies are reproduced only within 2 MeV. This implies that conventional
multipole moments do not provide fully adequate variables for a shape dynamics
of heavy nuclei.Comment: 15 pages, 11 figure
Applications of the dynamical generator coordinate method to quadrupole excitations
We apply the dynamical generator coordinate method (DGCM) with a conjugate
momentum to a nuclear collective excitation. To this end, we first discuss how
to construct a numerically workable scheme of the DGCM for a general one-body
operator. We then apply the DGCM to the quadrupole vibration of O using
the Gogny D1S interaction. We show that both the ground state energy and the
excitation energies are lowered as compared to the conventional GCM with the
same number of basis functions. We also compute the sum rule values for the
quadrupole and monopole operators, and show that the DGCM yields more
consistent results than the conventional GCM to the values from the double
commutator. These results imply that the conjugate momentum is an important and
relevant degree of freedom in collective motions.Comment: 9 pages, 4 figure
Analysis of a Skyrme energy density functional with deep learning
Over the past decade, machine learning has been successfully applied in
various fields of science. In this study, we employ a deep learning method to
analyze a Skyrme energy density functional (Skyrme-EDF), that is a Kohn-Sham
type functional commonly used in nuclear physics. Our goal is to construct an
orbital-free functional that reproduces the results of the Skyrme-EDF. To this
end, we first compute energies and densities of a nucleus with the Skyrme
Kohn-Sham + Bardeen-Cooper-Schrieffer method by introducing a set of external
fields. Those are then used as training data for deep learning to construct a
functional which depends only on the density distribution. Applying this scheme
to the Mg nucleus with two distinct random external fields, we
successfully obtain a new functional which reproduces the binding energy of the
original Skyrme-EDF with an accuracy of about 0.04 MeV. The rate at which the
neural network outputs the energy for a given density is about --
times faster than the Kohn-Sham scheme, demonstrating a promising potential for
applications to heavy and superheavy nuclei, including the dynamics of fission.Comment: 16 pages, 9 figure
Research of the Field Placement Record : Review of the Field Placement Article
本稿は,社会福祉実習指導体系確立の一助となることを目的として,特に「実習記録」の概念枠組みについて社会福祉実習関係文献をもとに整理・検討したものである。はじめに「社会福祉実習」を,坪上宏の所論を援用し,「主体」,「対象」,「目的」,「手段」からなる人間実践のひとつと捉えた。そのうち,人間の内在的な力が「外化」し,「事実化」した「手段」は,意味付与を行う「主体」としての「人間」と切り離せないことを示した。そのうえで,仮説として「実習記録」を記述する際の8つのポイントを提示し,このポイントをふまえた記録からは,(1)「理論」,(2)「理論」をふまえた実習生の行動,(3)現場実践,という3つの局面間それぞれの差異が徐々にあらわれることを示した。そして,実習生がこの3つの差異を「実習記録」により意識し,整理・検証し,さらに記録することにより,「実習記録」は必然的に実習の「手段」となり得ることを示した。The purpose of this research is to consider the concept framework of field placement record on the basis of the field placement article in order to establish the system of field placement guidance. Firstly, I determined field placement as the practice that is composed of subject, object, purpose and means basis on Hiroshi Tsubokami's Social work Relationship theory. Secondly, I supposed eight point of field placement record. It showed that the difference between theory, field placement and practice gradually turns up from such a record. In concluding, I proposed that field placement record becomes the means of field placement through writing such a record
Clinical approaches towards asthma and chronic obstructive pulmonary disease based on the heterogeneity of disease pathogenesis
Asthma and chronic obstructive pulmonary disease (COPD) are each heterogeneous disease classifications that include several clinical and pathophysiological phenotypes. This heterogeneity complicates characterization of each disease and, in some cases, hinders the selection of appropriate treatment. Therefore, in recent years, emphasis has been placed on improving our understanding of the various phenotypes of asthma and of COPD and identifying biomarkers for each phenotype. Likewise, the concept of the endotype has been gaining acceptance; an endotype is a disease subtype that is defined by unique or distinctive functional or pathophysiological mechanisms. Endotypes of asthma or COPD may be primarily characterized by increased susceptibility to type 2 inflammation, increased susceptibility to viral infections, bacterial colonization or impaired lung development. The ‘Dutch hypothesis’ is as follows: gene variants underlying particular endotypes interact with detrimental environmental stimuli (e.g. smoking, viral infection and air pollution) and contribute to the ultimate development of asthma, COPD or both. Novel approaches that involve multidimensional assessment should facilitate identification and management of the components that generate this heterogeneity. Ultimately, patients with chronic inflammatory lung diseases may be treated based on these endotypes as determined by the respective biomarkers that correspond to individual endotypes instead of on disease labels such as asthma, COPD or even asthma–COPD overlap syndrome (ACOS)
Generator coordinate method with a conjugate momentum: application to the particle number projection
We discuss an extension of the generator coordinate method (GCM) by taking
simultaneously a collective coordinate and its conjugate momentum as generator
coordinates. To this end, we follow the idea of the dynamical GCM (DGCM)
proposed by Goeke and Reinhard. We first show that the DGCM method can be
regarded as an extension of the double projection method for the center of mass
motion. As an application of DGCM, we then investigate the particle number
projection, for which we not only carry out an integral over the gauge angle as
in the usual particle number projection but also take a linear superposition of
BCS states which have different mean particle numbers. We show that the ground
state energy is significantly lowered by such effect, especially for magic
nuclei for which the pairing gap is zero in the BCS approximation. This
suggests that the present method makes a good alternative to the variation
after projection (VAP) method, as the method is much simpler than the VAP.Comment: 9 pages, 4 figure
Analysis of a Skyrme energy density functional with deep learning
Over the past decade, machine learning has been successfully applied in various fields of science. In this study, we employ a deep learning method to analyze a Skyrme energy density functional (Skyrme-EDF), which is a Kohn-Sham type functional commonly used in nuclear physics. Our goal is to construct an orbital-free functional that reproduces the results of the Skyrme-EDF. To this end, we first compute energies and densities of a nucleus with the Skyrme Kohn-Sham + Bardeen-Cooper-Schrieffer method by introducing a set of external fields. Those are then used as training data for deep learning to construct a functional which depends only on the density distribution. Applying this scheme to the ²⁴Mg nucleus with two distinct random external fields, we successfully obtain a new functional which reproduces the binding energy of the original Skyrme-EDF with an accuracy of about 0.04 MeV. The rate at which the neural network outputs the energy for a given density is about 10⁵–10⁶ times faster than the Kohn-Sham scheme, demonstrating a promising potential for applications to heavy and superheavy nuclei, including the dynamics of fission
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The distribution of blood eosinophil levels in a Japanese COPD clinical trial database and in the rest of the world.
Background: Blood eosinophil measurements may help to guide physicians on the use of inhaled corticosteroids (ICS) for patients with chronic obstructive pulmonary disease (COPD). Emerging data suggest that COPD patients with higher blood eosinophil counts may be at higher risk of exacerbations and more likely to benefit from combined ICS/long-acting beta2-agonist (LABA) treatment than therapy with a LABA alone. This analysis describes the distribution of blood eosinophil count at baseline in Japanese COPD patients in comparison with non-Japanese COPD patients. Methods: A post hoc analysis of eosinophil distribution by percentage and absolute cell count was performed across 12 Phase II-IV COPD clinical studies (seven Japanese studies [N=848 available absolute eosinophil counts] and five global studies [N=5,397 available eosinophil counts] that included 246 Japanese patients resident in Japan with available counts). Blood eosinophil distributions were assessed at baseline, before blinded treatment assignment. Findings: Among Japanese patients, the median (interquartile range) absolute eosinophil count was 170 cells/mm3(100-280 cells/mm3). Overall, 612/1,094 Japanese patients (56%) had an absolute eosinophil count ≥150 cells/mm3and 902/1,304 Japanese patients (69%) had a percentage eosinophil ≥2%. Among non-Japanese patients, these values were 160 (100-250) cells/mm3, 2,842/5,151 patients (55%), and 2,937/5,155 patients (57%), respectively. The eosinophil distribution among Japanese patients was similar to that among non-Japanese patients. Within multi-country studies with similar inclusion criteria, the eosinophil count was numerically lower in Japanese compared with non-Japanese patients (median 120 vs 160 cells/mm3). Interpretation: The eosinophil distribution in Japanese patients seems comparable to that of non-Japanese patients; although within multi-country studies, there was a slightly lower median eosinophil count for Japanese patients compared with non-Japanese patients. These findings suggest that blood eosinophil data from global studies are of relevance in Japan
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