4,720 research outputs found
Who are Cross-Border Online Shoppers?
Cross-border online purchase has been significantly increased throughout the world thanks to the development of transportation and technology. Understanding cross-border online shopping behavior in South Korea is particularly important due to its dramatic growth. Since 2010, cross-border online shopping has been increased by 40% every year (Korean Consumer Agency, 2014). This study is to enhance the understanding of cross-border online shopping behavior in South Korea. Based on the Theory of Reasoned Action (TRA), specifically, this study examined the relationships among consumer beliefs, attitude, subjective norms, and purchase intention for cross-border online shopping. This results of this research demonstrated that building a positive attitude toward cross-border online shopping, which was influenced by global orientation, ethnocentrism, and global brand beliefs, was the powerful antecedent of purchase intention for cross-border shopping
Temperature-dependent evolutions of excitonic superfluid plasma frequency in a srong excitonic insulator candidate, TaNiSe
We investigate an interesting anisotropic van der Waals material,
TaNiSe, using optical spectroscopy. TaNiSe has been
known as one of the few excitonic insulators proposed over 50 years ago.
TaNiSe has quasi-one dimensional chains along the -axis. We have
obtained anisotropic optical properties of a single crystal TaNiSe
along the - and -axes. The measured - and -axis optical
conductivities exhibit large anisotropic electronic and phononic properties.
With regard to the -axis optical conductivity, a sharp peak near 3050
cm at 9 K, with a well-defined optical gap ( 1800
cm) and a strong temperature-dependence, is observed. With an increase
in temperature, this peak broadens and the optical energy gap closes around
325 K(). The spectral weight redistribution with respect to the
frequency and temperature indicates that the normalized optical energy gap
() is . The
temperature-dependent superfluid plasma frequency of the excitonic condensation
in TaNiSe has been determined from measured optical data. Our
findings may be useful for future research on excitonic insulators.Comment: 17 pages, 5 figure
Convolution channel separation and frequency sub-bands aggregation for music genre classification
In music, short-term features such as pitch and tempo constitute long-term
semantic features such as melody and narrative. A music genre classification
(MGC) system should be able to analyze these features. In this research, we
propose a novel framework that can extract and aggregate both short- and
long-term features hierarchically. Our framework is based on ECAPA-TDNN, where
all the layers that extract short-term features are affected by the layers that
extract long-term features because of the back-propagation training. To prevent
the distortion of short-term features, we devised the convolution channel
separation technique that separates short-term features from long-term feature
extraction paths. To extract more diverse features from our framework, we
incorporated the frequency sub-bands aggregation method, which divides the
input spectrogram along frequency bandwidths and processes each segment. We
evaluated our framework using the Melon Playlist dataset which is a large-scale
dataset containing 600 times more data than GTZAN which is a widely used
dataset in MGC studies. As the result, our framework achieved 70.4% accuracy,
which was improved by 16.9% compared to a conventional framework
Integrated Parameter-Efficient Tuning for General-Purpose Audio Models
The advent of hyper-scale and general-purpose pre-trained models is shifting
the paradigm of building task-specific models for target tasks. In the field of
audio research, task-agnostic pre-trained models with high transferability and
adaptability have achieved state-of-the-art performances through fine-tuning
for downstream tasks. Nevertheless, re-training all the parameters of these
massive models entails an enormous amount of time and cost, along with a huge
carbon footprint. To overcome these limitations, the present study explores and
applies efficient transfer learning methods in the audio domain. We also
propose an integrated parameter-efficient tuning (IPET) framework by
aggregating the embedding prompt (a prompt-based learning approach), and the
adapter (an effective transfer learning method). We demonstrate the efficacy of
the proposed framework using two backbone pre-trained audio models with
different characteristics: the audio spectrogram transformer and wav2vec 2.0.
The proposed IPET framework exhibits remarkable performance compared to
fine-tuning method with fewer trainable parameters in four downstream tasks:
sound event classification, music genre classification, keyword spotting, and
speaker verification. Furthermore, the authors identify and analyze the
shortcomings of the IPET framework, providing lessons and research directions
for parameter efficient tuning in the audio domain.Comment: 5 pages, 3 figures, submit to ICASSP202
One-Step Knowledge Distillation and Fine-Tuning in Using Large Pre-Trained Self-Supervised Learning Models for Speaker Verification
The application of speech self-supervised learning (SSL) models has achieved
remarkable performance in speaker verification (SV). However, there is a
computational cost hurdle in employing them, which makes development and
deployment difficult. Several studies have simply compressed SSL models through
knowledge distillation (KD) without considering the target task. Consequently,
these methods could not extract SV-tailored features. This paper suggests
One-Step Knowledge Distillation and Fine-Tuning (OS-KDFT), which incorporates
KD and fine-tuning (FT). We optimize a student model for SV during KD training
to avert the distillation of inappropriate information for the SV. OS-KDFT
could downsize Wav2Vec 2.0 based ECAPA-TDNN size by approximately 76.2%, and
reduce the SSL model's inference time by 79% while presenting an EER of 0.98%.
The proposed OS-KDFT is validated across VoxCeleb1 and VoxCeleb2 datasets and
W2V2 and HuBERT SSL models. Experiments are available on our GitHub
Distinct mechanisms of decadal subsurface heat content variations in the eastern and western Indian Ocean modulated by tropical Pacific SST
Author Posting. © American Meteorological Society, 2018. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 31 (2018): 7751-7769, doi:10.1175/JCLI-D-18-0184.1.Decadal variability of the subsurface ocean heat content (OHC) in the Indian Ocean is investigated using a coupled climate model experiment, in which observed eastern tropical Pacific sea surface temperature (EPSST) anomalies are specified. This study intends to understand the contributions of external forcing relative to those of internal variability associated with EPSST, as well as the mechanisms by which the Pacific impacts Indian Ocean OHC. Internally generated variations associated with EPSST dominate decadal variations in the subsurface Indian Ocean. Consistent with ocean reanalyses, the coupled model reproduces a pronounced east–west dipole structure in the southern tropical Indian Ocean and discontinuities in westward-propagating signals in the central Indian Ocean around 100°E. This implies distinct mechanisms by which the Pacific impacts the eastern and western Indian Ocean on decadal time scales. Decadal variations of OHC in the eastern Indian Ocean are attributed to 1) western Pacific surface wind anomalies, which trigger oceanic Rossby waves propagating westward through the Indonesian Seas and influence Indonesian Throughflow transport, and 2) zonal wind anomalies over the central tropical Indian Ocean, which trigger eastward-propagating Kelvin waves. Decadal variations of OHC in the western Indian Ocean are linked to conditions in the Pacific via changes in the atmospheric Walker cell, which trigger anomalous wind stress curl and Ekman pumping in the central tropical Indian Ocean. Westward-propagating oceanic Rossby waves extend the influence of this anomalous Ekman pumping to the western Indian Ocean.This research was supported by
the Independent Research and Development Program
at WHOI to CCU, an NSF OCE PO grant (NSF OCE-
1242989) to Young-Oh Kwon, NOAA CP CVP grants
(NA15OAR4310176 and NA17OAR4310255) to Hyodae
Seo, and a research grant fromtheMinistry of Science and
Technology of the People’s Republic of China to Tsinghua
University (2017YFA0603902).2019-02-1
PAS: Partial Additive Speech Data Augmentation Method for Noise Robust Speaker Verification
Background noise reduces speech intelligibility and quality, making speaker
verification (SV) in noisy environments a challenging task. To improve the
noise robustness of SV systems, additive noise data augmentation method has
been commonly used. In this paper, we propose a new additive noise method,
partial additive speech (PAS), which aims to train SV systems to be less
affected by noisy environments. The experimental results demonstrate that PAS
outperforms traditional additive noise in terms of equal error rates (EER),
with relative improvements of 4.64% and 5.01% observed in SE-ResNet34 and
ECAPA-TDNN. We also show the effectiveness of proposed method by analyzing
attention modules and visualizing speaker embeddings.Comment: 5 pages, 2 figures, 1 table, accepted to CKAIA2023 as a conference
pape
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
Recommended from our members
Knockdown of Ant2 Reduces Adipocyte Hypoxia And Improves Insulin Resistance in Obesity.
Decreased adipose tissue oxygen tension and increased HIF-1α expression can trigger adipose tissue inflammation and dysfunction in obesity. Our current understanding of obesity-associated decreased adipose tissue oxygen tension is mainly focused on changes in oxygen supply and angiogenesis. Here, we demonstrate that increased adipocyte O2 demand, mediated by ANT2 activity, is the dominant cause of adipocyte hypoxia. Deletion of adipocyte Ant2 improves obesity-induced intracellular adipocyte hypoxia by decreasing obesity-induced adipocyte oxygen demand, without effects on mitochondrial number or mass, or oligomycin-sensitive respiration. This led to decreased adipose tissue HIF-1α expression and inflammation with improved glucose tolerance and insulin resistance in both a preventative or therapeutic setting. Our results suggest that ANT2 may be a target for the development of insulin sensitizing drugs and that ANT2 inhibition might have clinical utility
- …