BIOMECHANICAL CHARACTERISTICS OF KINEMATICS IN LONG JUMPERS

The maximum speed attained by the athlete in broad jump competition is an important objective for the approach phase of the jump. Although the technique of male broad jump athletes has been studied, very little research has focussed on the performance of female high performance broad jump athletes. The purpose of this study was to analyze the characteristics of movement kinematics in three males and three females broad jumpers. A comparison of performance between the males and females was made so as to provide the information for coaches and athletes to improve performance

Nonlinear Hall Effects in Strained Twisted Bilayer WSe2_2

Recently, it has been pointed out that the twisting of bilayer WSe$_2$ would generate topologically non-trivial flat bands near the Fermi energy. In this work, we show that twisted bilayer WSe$_2$ (tWSe$_2$) with uniaxial strain exhibits a large nonlinear Hall (NLH) response due to the non-trivial Berry curvatures of the flat bands. Moreover, the NLH effect is greatly enhanced near the topological phase transition point which can be tuned by a vertical displacement field. Importantly, the nonlinear Hall signal changes sign across the topological phase transition point and provides a way to identify the topological phase transition and probe the topological properties of the flat bands. The strong enhancement and high tunability of the NLH effect near the topological phase transition point renders tWSe$_2$ and related moire materials new platforms for rectification and second harmonic generations.Comment: 5 pages, 3 figures. Comments are welcom

Research on Innovation Ecosystem of the Crowd Innovation Space Based on System Dynamics

The crowd innovation space is a new innovation business service platform, developed from the traditional incubator, including makerspace, entrepreneurship café and so on. It is essential for mass entrepreneurship and innovation to get full use of the creativity of the crowed innovation space and explore new impetus in New Economic Norm. Based on the traditional enterprise innovation ecosystem theory, this paper explores the connotation of innovation ecosystem of the crowd innovation space. And then, we use the knowledge to model the innovation ecosystem of the crowd innovation space with system dynamics. Based on the model, we explore the operational mechanism of innovation ecosystem of the crowd innovation space. Through the analysis of the operational mechanism and connotation, we put forward to some proposal to improve the effectiveness of the service ability in innovation of the crowd innovation space

Identifying Chinese Leading Venture Capital Firms Based on Graph Convolutional Neural Networks

It is a meaningful challenge to identify leading venture capital firms (VCs) in the analysis of the Chinese investment market. Identifying leading VCs is equal to determine influential nodes in the field of complex network analysis. Many studies have applied centrality measures to determine influence nodes. However, only a few studies have explored more efficient and flexible ways to accomplish this task. In this work, we propose a new approach which using graph convolutional neural networks to identify influential nodes in the network, so as to determine leading VCs. We build an undirected graph based on co-investment of VCs, then learn a VCs Graph Convolutional Neural Network (vcGCNN) for nodes classification. Our vcGCNN is labeled with ‘1’ and ‘0’ for ‘is leading VCs’ and ‘is not leading VCs’. The experiment results on VCs dataset demonstrate that vcGCNN outperforms multiple centrality measures and some typical spectral-based GNN methods for leading venture capital firms identification

Berry curvature, spin Hall effect and nonlinear optical response in moir\'e transition metal dichalcogenide heterobilayers

Recently, the topological flat bands and spin Hall effect have been experimentally observed in the AB-stacked MoTe$_2$/WSe$_2$ heterostructures. In this work, we systematically study the Berry curvature effects in moir\'{e} transition metal dichalcogenide (TMD) heterobilayers. We point out that the moir\'{e} potential of the remote conduction bands would induce a sizable periodic pseudo-magnetic field (PMF) on the valence band. This periodic PMF creates net Berry curvature flux in each valley of the moir\'{e} Brillouin zone. The combination of the effect of the Berry curvature and the spin-valley locking can induce the spin Hall effect being observed in the experiment. Interestingly, the valley-contrasting Berry curvature distribution generated by the PMF can be probed through shift currents, which are DC currents induced by linearly polarized lights through nonlinear responses. Our work shed lights on the novel quantum phenomena induced by Berry curvatures in moir\'e TMD heterobilayers.Comment: 10 pages, 7 figure

Numerical simulation on the influence of stirrups during electrochemical repair

Stirrup in the concrete structure has noteworthy effect on the electrochemical chloride removal (ECR), which was always ignored in the numerical simulation. Taking the impact of stirrup into consideration has disadvantages on improving the accurate of modeling results. In this paper, a three dimensional (3D) numerical model considering the impact of stirrup on ECR treatment was established, and an experiment was numerically studied to explore the validity of the model. The difference between the residual chloride concentration of simulation and experiment in most region of the concrete structure is within ± 25%. Based on this model, the effect of stirrups on ECR’s efficiency were explored. The results of numerical model shows that the stirrup has shielding effect on the chloride migration of the region between the stirrups, while in the region near the stirrup, it has positive on the chloride removal. TRANSLATE with x English Arabic Hebrew Polish Bulgarian Hindi Portuguese Catalan Hmong Daw Romanian Chinese Simplified Hungarian Russian Chinese Traditional Indonesian Slovak Czech Italian Slovenian Danish Japanese Spanish Dutch Klingon Swedish English Korean Thai Estonian Latvian Turkish Finnish Lithuanian Ukrainian French Malay Urdu German Maltese Vietnamese Greek Norwegian Welsh Haitian Creole Persian TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster Portal Back TRANSLATE with x English Arabic Hebrew Polish Bulgarian Hindi Portuguese Catalan Hmong Daw Romanian Chinese Simplified Hungarian Russian Chinese Traditional Indonesian Slovak Czech Italian Slovenian Danish Japanese Spanish Dutch Klingon Swedish English Korean Thai Estonian Latvian Turkish Finnish Lithuanian Ukrainian French Malay Urdu German Maltese Vietnamese Greek Norwegian Welsh Haitian Creole Persian TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster Portal Bac

Discrete Point-wise Attack Is Not Enough: Generalized Manifold Adversarial Attack for Face Recognition

Classical adversarial attacks for Face Recognition (FR) models typically generate discrete examples for target identity with a single state image. However, such paradigm of point-wise attack exhibits poor generalization against numerous unknown states of identity and can be easily defended. In this paper, by rethinking the inherent relationship between the face of target identity and its variants, we introduce a new pipeline of Generalized Manifold Adversarial Attack (GMAA) to achieve a better attack performance by expanding the attack range. Specifically, this expansion lies on two aspects - GMAA not only expands the target to be attacked from one to many to encourage a good generalization ability for the generated adversarial examples, but it also expands the latter from discrete points to manifold by leveraging the domain knowledge that face expression change can be continuous, which enhances the attack effect as a data augmentation mechanism did. Moreover, we further design a dual supervision with local and global constraints as a minor contribution to improve the visual quality of the generated adversarial examples. We demonstrate the effectiveness of our method based on extensive experiments, and reveal that GMAA promises a semantic continuous adversarial space with a higher generalization ability and visual qualityComment: Accepted by CVPR202

Photoplethysmographic imaging and analysis of pulsatile pressure wave in palmar artery at 10 wavelengths

CC BY: © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.Significance As a noncontact method, imaging photoplethysmography (iPPG) may provide a powerful tool to measure pulsatile pressure wave (PPW) in superficial arteries and extract biomarkers for monitoring of artery wall stiffness. Aim We intend to develop a approach for extraction of the very weak cardiac component from iPPG data by identifying locations of strong PPW signals with optimized illumination wavelength and determining pulse wave velocity (PWV). Approach Monochromatic in vivo iPPG datasets have been acquired from left hands to investigate various algorithms for retrieval of PPW signals, distribution maps and waveforms, and their dependence on arterial location and wavelength. Results A robust algorithm of pixelated independent component analysis (pICA) has been developed and combined with spatiotemporal filtering to retrieve PPW signals. Spatial distributions of PPW signals have been mapped in 10 wavelength bands from 445 to 940 nm and waveforms were analyzed at multiple locations near the palmar artery tree. At the wavelength of 850 nm selected for timing analysis, we determined PWV values from 12 healthy volunteers in a range of 0.5 to 5.8 m/s across the hand region from wrist to midpalm and fingertip.ECU Open Access Publishing Support Fun