China's post-coal growth

Slowing GDP growth, a structural shift away from heavy industry, and more proactive policies on air pollution and clean energy have caused China's coal use to peak. It seems that economic growth has decoupled from growth in coal consumption

The influence of community factors on local entrepreneurs' support for tourism

This study probes the influence of community attachment on local entrepreneurs’ perceptions of tourism’s local impacts. Six latent constructs were derived from social exchange theory and community attachment theory; 11 hypotheses were tested, using structural equation modelling, with data from 297 Taiwanese night market entrepreneurs. Significant theoretical contributions to understanding relationships between entrepreneurs and community were found: effects of community satisfaction on support for tourism were significant and fully mediated by perceived benefits. Community factors and tourist contact frequency were important in entrepreneurs’ decisions on further tourism development. Community factors showed low but significant relationships with the perceived costs of tourism, A case is made for sustainable tourism governance measures, including partnership creation, destination management systems, and visitor experience planning

A Brain-inspired Hierarchical Interactive In-memory Computing System and its Application in Video Sentiment Analysis

Fundamental Research Funds for the Provincial University of Zhejiang (Grant Number: GK229909299001-06); 10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 62001149); 10.13039/501100004731-Natural Science Foundation of Zhejiang Province (Grant Number: LQ21F010009)

EMSN: An Energy-Efficient Memristive Sequencer Network for Human Emotion Classification in Mental Health Monitoring

Fundamental Research Funds for the Provincial University of Zhejiang (Grant Number: GK229909299001-06); 10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 62001149); Natural Science Foundation of Zhejiang Province (Grant Number: LQ21F010009)

Frustrated ferromagnetic transition in AB-stacked honeycomb bilayer

In two-dimensional (2D) ferromagnets, anisotropy is essential for the magnetic ordering as dictated by the Mermin-Wagner theorem. But when competing anisotropies are present, the phase transition becomes nontrivial. Here, utilizing highly sensitive susceptometry of scanning superconducting quantum interference device microscopy, we probe the spin correlations of ABC-stacked CrBr3 under zero magnetic field. We identify a plateau feature in susceptibility above the critical temperature (Tc) in thick samples. It signifies a crossover regime induced by the competition between easy-plane intralayer exchange anisotropy versus uniaxial interlayer anisotropy. The evolution of the critical behavior from the bulk to 2D shows that the competition between the anisotropies is magnified in the reduced dimension. It leads to a strongly frustrated ferromagnetic transition in the bilayer with fluctuation on the order of Tc, which is distinct from both the monolayer and the bulk. Our observation potentially offers a 2D localized spin system on honeycomb lattice to explore magnetic frustration

Memristive System Based Image Processing Technology: A Review and Perspective

Copyright: © 2021 by the authors. As the acquisition, transmission, storage and conversion of images become more efficient, image data are increasing explosively. At the same time, the limitations of conventional computational processing systems based on the Von Neumann architecture continue to emerge, and thus, improving the efficiency of image processing has become a key issue that has bothered scholars working on images for a long time. Memristors with non-volatile, synapse-like, as well as integrated storage-and-computation properties can be used to build intelligent processing systems that are closer to the structure and function of biological brains. They are also of great significance when constructing new intelligent image processing systems with non-Von Neumann architecture and for achieving the integrated storage and computation of image data. Based on this, this paper analyses the mathematical models of memristors and discusses their applications in conventional image processing based on memristive systems as well as image processing based on memristive neural networks, to investigate the potential of memristive systems in image processing. In addition, recent advances and implications of memristive system-based image processing are presented comprehensively, and its development opportunities and challenges in different major areas are explored as well. By establishing a complete spectrum of image processing technologies based on memristive systems, this review attempts to provide a reference for future studies in the field, and it is hoped that scholars can promote its development through interdisciplinary academic exchanges and cooperationNational Natural Science Foundation of China (Grant U1909201, Grant 62001149); Natural Science Foundation of Zhejiang Province (Grant LQ21F010009)

Direct electronic measurement of the spin Hall effect

The generation, manipulation and detection of spin-polarized electrons in nanostructures define the main challenges of spin-based electronics[1]. Amongst the different approaches for spin generation and manipulation, spin-orbit coupling, which couples the spin of an electron to its momentum, is attracting considerable interest. In a spin-orbit-coupled system, a nonzero spin-current is predicted in a direction perpendicular to the applied electric field, giving rise to a "spin Hall effect"[2-4]. Consistent with this effect, electrically-induced spin polarization was recently detected by optical techniques at the edges of a semiconductor channel[5] and in two-dimensional electron gases in semiconductor heterostructures[6,7]. Here we report electrical measurements of the spin-Hall effect in a diffusive metallic conductor, using a ferromagnetic electrode in combination with a tunnel barrier to inject a spin-polarized current. In our devices, we observe an induced voltage that results exclusively from the conversion of the injected spin current into charge imbalance through the spin Hall effect. Such a voltage is proportional to the component of the injected spins that is perpendicular to the plane defined by the spin current direction and the voltage probes. These experiments reveal opportunities for efficient spin detection without the need for magnetic materials, which could lead to useful spintronics devices that integrate information processing and data storage.Comment: 5 pages, 4 figures. Accepted for publication in Nature (pending format approval

Active optical clock based on four-level quantum system

Active optical clock, a new conception of atomic clock, has been proposed recently. In this report, we propose a scheme of active optical clock based on four-level quantum system. The final accuracy and stability of two-level quantum system are limited by second-order Doppler shift of thermal atomic beam. To three-level quantum system, they are mainly limited by light shift of pumping laser field. These limitations can be avoided effectively by applying the scheme proposed here. Rubidium atom four-level quantum system, as a typical example, is discussed in this paper. The population inversion between $6S_{1/2}$ and $5P_{3/2}$ states can be built up at a time scale of $10^{-6}$s. With the mechanism of active optical clock, in which the cavity mode linewidth is much wider than that of the laser gain profile, it can output a laser with quantum-limited linewidth narrower than 1 Hz in theory. An experimental configuration is designed to realize this active optical clock.Comment: 5 page

Study on Arrhenius model of TC6 titanium alloy

At the deformation temperature of 1 103-1 283 K, with strain rate of 0,01 – 10 s-1, and total strain of 0,7, the deformation behavior of TC6 titanium alloy was studied. The Arrhenius constitutive model is established by using stress - strain data when the strains of TC6 titanium alloy are 0,05, 0,1, 0,2, 0,3, 0,4, 0,5, 0,55, 0,6, and the accuracy of the model was verified. The results show that: the flow stress of TC6 titanium alloy increases as the strain rate increases and decreases as the deformation temperature increases; under different strains, the correlation coefficient (R) between the experimental value and the predicted value is greater than 98 %, and the average relative error (AARE) is lower than 10 %, which suggests that the established model has a higher prediction

KFe_2Se_2 is the parent compound of K-doped iron selenide superconductors

We elucidate the existing controversies in the newly discovered K-doped iron selenide (KxFe2-ySe2-z) superconductors. The stoichiometric KFe2Se2 with \surd2\times\surd2 charge ordering was identified as the parent compound of KxFe2-ySe2-z superconductor using scanning tunneling microscopy and spectroscopy. The superconductivity is induced in KFe2Se2 by either Se vacancies or interacting with the anti-ferromagnetic K2Fe4Se5 compound. Totally four phases were found to exist in KxFe2-ySe2-z: parent compound KFe2Se2, superconducting KFe2Se2 with \surd2\times\surd5 charge ordering, superconducting KFe2Se2-z with Se vacancies and insulating K2Fe4Se5 with \surd5\times\surd5 Fe vacancy order. The phase separation takes place at the mesoscopic scale under standard molecular beam epitaxy condition