22,465 research outputs found
Spherical to deformed shape transition in the nucleon-pair shell model
A study of the shape transition from spherical to axially deformed nuclei in
the even Ce isotopes using the nucleon-pair approximation of the shell model is
reported. As long as the structure of the dominant collective pairs is
determined using a microscopic framework appropriate to deformed nuclei, the
model is able to produce a shape transition. However, the resulting transition
is too rapid, with nuclei that should be transitional being fairly well
deformed, perhaps reflecting the need to maintain several pairs with each
angular momentum.Comment: 7 pages, 5 figure
Two-stage hybrid feature selection algorithms for diagnosing erythemato-squamous diseases
This paper proposes two-stage hybrid feature selection algorithms to build the stable and efficient diagnostic models where a new accuracy measure is introduced to assess the models. The two-stage hybrid algorithms adopt Support Vector Machines (SVM) as a classification tool, and the extended Sequential Forward Search (SFS), Sequential Forward Floating Search (SFFS), and Sequential Backward Floating Search (SBFS), respectively, as search strategies, and the generalized F-score (GF) to evaluate the importance of each feature. The new accuracy measure is used as the criterion to evaluated the performance of a temporary SVM to direct the feature selection algorithms. These hybrid methods combine the advantages of filters and wrappers to select the optimal feature subset from the original feature set to build the stable and efficient classifiers. To get the stable, statistical and optimal classifiers, we conduct 10-fold cross validation experiments in the first stage; then we merge the 10 selected feature subsets of the 10-cross validation experiments, respectively, as the new full feature set to do feature selection in the second stage for each algorithm. We repeat the each hybrid feature selection algorithm in the second stage on the one fold that has got the best result in the first stage. Experimental results show that our proposed two-stage hybrid feature selection algorithms can construct efficient diagnostic models which have got better accuracy than that built by the corresponding hybrid feature selection algorithms without the second stage feature selection procedures. Furthermore our methods have got better classification accuracy when compared with the available algorithms for diagnosing erythemato-squamous diseases
Inverse Spin Hall Effect by Spin Injection
Motivated by a recent experiment[Nature {\bf 442}, 176 (2006)], we present a
quantitative microscopic theory to investigate the inverse spin-Hall effect
with spin injection into aluminum considering both intrinsic and extrinsic
spin-orbit couplings using the orthogonalized-plane-wave method. Our
theoretical results are in good agreement with the experimental data. It is
also clear that the magnitude of the anomalous Hall resistivity is mainly due
to contributions from extrinsic skew scattering, while its spatial variation is
determined by the intrinsic spin-orbit coupling.Comment: 5 pages, 3 figure
Glassy Dynamics in a Frustrated Spin System: Role of Defects
In an effort to understand the glass transition, the kinetics of a spin model
with frustration but no quenched randomness has been analyzed. The
phenomenology of the spin model is remarkably similiar to that of structural
glasses. Analysis of the model suggests that defects play a major role in
dictating the dynamics as the glass transition is approached.Comment: 9 pages, 5 figures, accepted in J. Phys.: Condensed Matter,
proceedings of the Trieste workshop on "Unifying Concepts in Glass Physics
On Listening Teaching of TCFL and Cultivating the Ability of Listening and Speaking
Listening is an essential part of TCFL, but, listening class should not be just limited to listen and doing listening exercises, it should combine hearing training and verbal training and should focus on cultivating students’ language-thinking ability. What it teaches should be flexible to make teaching live and practical.
Keywords: TCFL, listening teaching, ability of listening and speakin
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