12,426 research outputs found
Dimerization-Induced Fermi-Surface Reconstruction in IrTe2
We report a de Haas-van Alphen (dHvA) oscillation study on IrTe2 single crystals showing complex dimer formations. By comparing the angle dependence of dHvA oscillations with band structure calculations, we show distinct Fermi surface reconstruction induced by a 1/5-type and a 1/8-type dimerizations. This verifies that an intriguing quasi-two-dimensional conducting plane across the layers is induced by dimerization in both cases. A phase transition to the 1/8 phase with higher dimer density reveals that local instabilities associated with intra-and interdimer couplings are the main driving force for complex dimer formations in IrTe2.X11149sciescopu
Successive spin-flop transitions of a Neel-type antiferromagnet Li2MnO3 single crystal with a honeycomb lattice
We have carried out high magnetic field studies of single-crystalline Li2MnO3, a honeycomb lattice antiferromagnet. Its magnetic phase diagram was mapped out using magnetization measurements at applied fields up to 35 T. Our results show that it undergoes two successive meta-magnetic transitions around 9 T fields applied perpendicular to the ab plane (along the c* axis). These phase transitions are completely absent in the magnetization measured with the field applied along the ab plane. In order to understand this magnetic phase diagram, we developed a mean-field model starting from the correct Neel-type magnetic structure, consistent with our single crystal neutron diffraction data at zero field. Our model calculations succeeded in explaining the two meta-magnetic transitions that arise when Li2MnO3 enters two different spin-flop phases from the zero field Neel phase.open1187Nsciescopu
A cross-cultural study of mood in K-POP Songs
Prior research suggests that music mood is one of the most important criteria when people look for music – but the perception of mood may be subjective and can be influenced by many factors including the listeners’ cultural background. In recent years, the number of studies of music mood perceptions by various cultural groups and of automated mood classification of music from different cultures has been increasing. However, there has yet to be a well-established testbed for evaluating cross-cultural tasks in Music Information Retrieval (MIR). Moreover, most existing datasets in MIR consist mainly of Western music and the cultural backgrounds of the annotators were mostly not taken into consideration or were limited to one cultural group. In this study, we built a collection of 1,892 K-pop (Korean Pop) songs with mood annotations collected from both Korean and American listeners, based on three different mood models. We analyze the differences and similarities between the mood judgments of the two listener groups, and propose potential MIR tasks that can be evaluated on this dataset. © Xiao Hu, Jin Ha Lee, Kahyun Choi, J. Stephen Downie.published_or_final_versio
Genetic Comparison of Stemness of Human Umbilical Cord and Dental Pulp
published_or_final_versio
Magnetic Properties of Dilute Alloys: Equations for Magnetization and its Structural Fluctuations
The dilute Heisenberg ferromagnet is studied taking into account fluctuations
of magnetization caused by disorder. A self-consistent system of equations for
magnetization and its mean quadratic fluctuations is derived within the
configurationally averaged two-time temperature Green's function method. This
system of equations is analised at low concentration of non-magnetic
impurities. Mean relative quadratic fluctuations of magnetization are revealed
to be proportional to the square of concentration of impurities.Comment: 16 pages, LaTe
Quantum Oscillation Signatures of Pressure-induced Topological Phase Transition in BiTeI
We report the pressure-induced topological quantum phase transition of BiTeI single crystals using Shubnikov-de Haas oscillations of bulk Fermi surfaces. The sizes of the inner and the outer FSs of the Rashba-split bands exhibit opposite pressure dependence up to P=3.35 GPa, indicating pressure-tunable Rashba effect. Above a critical pressure P similar to 2 GPa, the Shubnikov-de Haas frequency for the inner Fermi surface increases unusually with pressure, and the Shubnikov-de Haas oscillations for the outer Fermi surface shows an abrupt phase shift. In comparison with band structure calculations, we find that these unusual behaviors originate from the Fermi surface shape change due to pressure-induced band inversion. These results clearly demonstrate that the topological quantum phase transition is intimately tied to the shape of bulk Fermi surfaces enclosing the time-reversal invariant momenta with band inversion.11117Ysciescopu
WiMIR: An Informetric Study on Women Authors in ISMIR
Poster session 3: paper no. PS3-29Organized by New York University and Columbia UniversityThe Music Information Retrieval (MIR) community is becoming increasingly aware of a gender imbalance evident in ISMIR participation and publication. This paper reports upon a comprehensive informetric study of the publication, authorship and citation characteristics of female researchers in the context of the ISMIR conferences. All 1,610 papers in the ISMIR proceedings written by 1,910 unique authors from 2000 to 2015 were collected and analyzed. Only 14.1% of all papers were led by female researchers. Temporal analysis shows that the percentage of lead female authors has not improved over the years, but more papers have appeared with female coauthors in very recent years. Topics and citation numbers are also analyzed and compared between female and male authors to identify research emphasis and to measure impact. The results show that the most prolific authors of both genders published similar numbers of ISMIR papers and the citation counts of lead authors in both genders had no significant difference. We also analyzed the collaboration patterns to discover whether gender is related to the number of collaborators. Implications of these findings are discussed and suggestions are proposed on how to continue encouraging and supporting female participation in the MIR field.published_or_final_versio
Higgs production in CP-violating supersymmetric cascade decays: probing the `open hole' at the Large Hadron Collider
A benchmark CP-violating supersymmetric scenario (known as 'CPX-scenario' in
the literature) is studied in the context of the Large Hadron Collider (LHC).
It is shown that the LHC, with low to moderate accumulated luminosity, will be
able to probe the existing `hole' in the - plane, which
cannot be ruled out by the LEP data. We explore the parameter space with
cascade decay of third generation squarks and gluino with CP-violating decay
branching fractions. We propose a multi-channel analysis to probe this
parameter space some of which are background free at an integrated luminosity
of 5-10 fb. Specially, multi-lepton final states (3\l,\, 4\l and like
sign di-lepton) are almost background free and have reach for the
corresponding signals with very early data of LHC for both 14 TeV and 7 TeV
center of mass energy.Comment: 24 pages, 9 figures, references added as in the journal versio
Fouling and its control in membrane distillation-A review
© 2014 Elsevier B.V. Membrane distillation (MD) is an emerging thermally-driven technology that poses a lot of promise in desalination, and water and wastewater treatment. Developments in membrane design and the use of alternative energy sources have provided much improvement in the viability of MD for different applications. However, fouling of membranes is still one of the major issues that hounds the long-term stability performance of MD. Membrane fouling is the accumulation of unwanted materials on the surface or inside the pores of a membrane that results to a detrimental effect on the overall performance of MD. If not addressed appropriately, it could lead to membrane damage, early membrane replacement or even shutdown of operation. Similar with other membrane separation processes, fouling of MD is still an unresolved problem. Due to differences in membrane structure and design, and operational conditions, the fouling formation mechanism in MD may be different from those of pressure-driven membrane processes. In order to properly address the problem of fouling, there is a need to understand the fouling formation and mechanism happening specifically for MD. This review details the different foulants and fouling mechanisms in the MD process, their possible mitigation and control techniques, and characterization strategies that can be of help in understanding and minimizing the fouling problem
Temperature dependence of the electronic structure of the J(eff)=12 Mott insulator Sr2IrO4 studied by optical spectroscopy
We investigated the temperature-dependent evolution of the electronic structure of the J(eff)=1/2 Mott insulator Sr2IrO4 using optical spectroscopy. The optical conductivity spectra sigma(omega) of this compound has recently been found to exhibit two d-d transitions associated with the transition between the J(eff)=1/2 and J(eff)=3/2 bands due to the cooperation of the electron correlation and spin-orbit coupling. As the temperature increases, the two peaks show significant changes resulting in a decrease in the Mott gap. The experimental observations are compared with the results of first-principles calculation in consideration of increasing bandwidth. We discuss the effect of the temperature change in the electronic structure of Sr2IrO4 in terms of local lattice distortion, excitonic effect, electron-phonon coupling, and magnetic ordering.open69575
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