32,212 research outputs found
Varieties in state capitalism and corporate innovation: evidence from an emerging economy
This paper contributes to the literature by examining the impact of different forms of state ownership on corporate innovation and the moderating effects of environmental, social, and governance (ESG) practices, economic policy uncertainty (EPU), and corruption in this ownership–innovation nexus. Building on both agency theory and institutional theory, we identify and divide the ultimate controlling shareholders into three types: central government, local government, and private shareholders. This study draws on data from 2629 listed firms in China between 2007 and 2015. Our results suggest that state-owned enterprises (SOEs) controlled by the central government show the strongest innovation performance in all scenarios. In addition, private firms outperform local SOEs in terms of patent quantity in both manufacturing and nonmanufacturing sectors and in high-economic-development regions, whereas local SOEs outperform their private peers with respect to patent quality, mainly in the manufacturing sector and high-economic-development regions. Such an ownership–innovation nexus is then found to be more pronounced for firms engaging in more ESG practices, during periods of higher EPU, and when less corruption is present. These findings demonstrate the value of diversity in state capitalism in guiding SOEs' heterogeneous innovation activities in emerging economies
High-frequency shoot regeneration of nodal explants from Tetrastigma hemsleyanum Diels et Gilg: A valuable medicinal plant
This paper describes the shoot regeneration of nodal segments from a medicinal plant, Tetrastigma hemsleyanum Diels et Gilg (Vitaceae). The highest number of shoots (7.27 shoots per explant) was observed in MS medium supplemented with 4 mg/l BA after six weeks of inoculation. 2 mg/l BA in combination with 0.1 mg/l NAA not only induced shoot proliferation but also increased shoot length. Well-developed shoots were rooted on half strength MS medium supplemented with 2 mg/l IBA with 100% rooting and 85% of the regenerated plantlets survived before been transferred to field conditions.Key words: Medicinal plant, nodal explants, shoot regeneration, Tetrastigma hemsleyanum
Momentum Distribution of Near-Zero-Energy Photoelectrons in the Strong-Field Tunneling Ionization in the Long Wavelength Limit
We investigate the ionization dynamics of Argon atoms irradiated by an
ultrashort intense laser of a wavelength up to 3100 nm, addressing the momentum
distribution of the photoelectrons with near-zero-energy. We find a surprising
accumulation in the momentum distribution corresponding to meV energy and a
\textquotedblleft V"-like structure at the slightly larger transverse momenta.
Semiclassical simulations indicate the crucial role of the Coulomb attraction
between the escaping electron and the remaining ion at extremely large
distance. Tracing back classical trajectories, we find the tunneling electrons
born in a certain window of the field phase and transverse velocity are
responsible for the striking accumulation. Our theoretical results are
consistent with recent meV-resolved high-precision measurements.Comment: 5 pages, 4 figure
Soft filter pruning for accelerating deep convolutional neural networks
© 2018 International Joint Conferences on Artificial Intelligence. All right reserved. This paper proposed a Soft Filter Pruning (SFP) method to accelerate the inference procedure of deep Convolutional Neural Networks (CNNs). Specifically, the proposed SFP enables the pruned filters to be updated when training the model after pruning. SFP has two advantages over previous works: (1) Larger model capacity. Updating previously pruned filters provides our approach with larger optimization space than fixing the filters to zero. Therefore, the network trained by our method has a larger model capacity to learn from the training data. (2) Less dependence on the pre-trained model. Large capacity enables SFP to train from scratch and prune the model simultaneously. In contrast, previous filter pruning methods should be conducted on the basis of the pre-trained model to guarantee their performance. Empirically, SFP from scratch outperforms the previous filter pruning methods. Moreover, our approach has been demonstrated effective for many advanced CNN architectures. Notably, on ILSCRC-2012, SFP reduces more than 42% FLOPs on ResNet-101 with even 0.2% top-5 accuracy improvement, which has advanced the state-of-the-art
Illumination and annealing characteristics of two-dimensional electron gas systems in metal-organic vapor-phase epitaxy grown AlGaN/AlN/GaN heterostructures
We studied the persistent photoconductivity (PPC) effect in AlGaN/AlN/GaN
heterostructures with two different Al-compositions (x=0.15 and x=0.25). The
two-dimensional electron gas formed at the AlN/GaN heterointerface was
characterized by Shubnikov-de Haas and Hall measurements. Using optical
illumination, we were able to increase the carrier density of the
Al0.15Ga0.85N/AlN/GaN sample from 1.6x10^{12} cm^{-2} to 5.9x1012 cm^{-2},
while the electron mobility was enhanced from 9540 cm2/Vs to 21400 cm2/Vs at T
= 1.6 K. The persistent photocurrent in both samples exhibited a strong
dependence on illumination wavelength, being highest close to the bandgap and
decreasing at longer wavelengths. The PPC effect became fairly weak for
illumination wavelengths longer than 530 nm and showed a more complex response
with an initial negative photoconductivity in the infrared region of the
spectrum (>700 nm). The maximum PPC-efficiency for 390 nm illumination was
0.011% and 0.005% for Al0.25Ga0.75N/AlN/GaN and Al0.15Ga0.85N/AlN/GaN samples,
respectively. After illumination, the carrier density could be reduced by
annealing the sample. Annealing characteristics of the PPC effect were studied
in the 20-280 K temperature range. We found that annealing at 280 K was not
sufficient for full recovery of the carrier density. In fact, the PPC effect
occurs in these samples even at room temperature. Comparing the measurement
results of two samples, the Al0.25Ga0.75N/AlN/GaN sample had a larger response
to illumination and displayed a smaller recovery with thermal annealing. This
result suggests that the energy scales of the defect configuration-coordinate
diagrams for these samples are different, depending on their Al-composition.Comment: 27 pages, 8 figure
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