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Superconductivity in chromium nitrides Pr3Cr10-xN11 with strong electron correlations

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National Science Review 2020年第1期7卷 21-26页

作者： Wei Wu Kai Liu Yanjie Li Zhenhai Yu Desheng Wu Yuting shao Shihang Na gang Li Ruizhen huang Tao Xiang Jianlin Luo Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices Renmin University of China School of Physical Science and Technology Shanghai Tech University Songshan Lake Materials Laboratory Kavli Institute for Theoretical Sciences

Exploration of superconductivity in Cr-based compounds has attracted considerable interest because only a few Cr-based superconductors(CrAs, A2Cr3As3and ACr3As3（A = K, Rb, Cs, Na）) have been discovered so far and they show an unconventional pairing mechanism. We report the discovery of bulk superconductivity at 5.25 K in chromium nitride in Pr3Cr10-xN11with a cubic lattice structure. A relatively large upper critical field of Hc2（0）～12.6 T is determined, which is larger than the estimated Pauli-paramagnetic pair-breaking magnetic field. The material has a large electronic specific-heat coefficient of 170 mJ K-2mol-1—about 10 times larger than that estimated by the electronic structure calculation,which suggests that correlations between 3d electrons are very strong in Pr3Cr10-xN11, and thus quantum fluctuations might be involved. Electronic structure calculations show that the density of states at the Fermi energy are contributed predominantly by Cr 3d electrons, implying that the superconductivity results mainly from the condensation of Cr 3d electrons. Pr3Cr10-xN11represents a rare example of possible unconventional superconductivity emerging in a 3D system with strong electron correlations. Nevertheless,clarification of the specific pairing symmetry needs more investigation.

关键词： Cr-based superconductors nitrides strong electron correlations unconventional superconductivity

A new result on global exponential robust stability of neural networks with time-varying delays

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控制理论与应用（英文版） 2009年第3期7卷 315-320页

作者： Jinliang shao Tingzhu huang School of Applied Mathematics University of Electronic Science and Technology of China Chengdu Sichuan 610054 China

In this paper, the global exponential robust stability of neural networks with ume-varying delays is investigated. By using nonnegative matrix theory and the Halanay inequality, a new sufficient condition for global exponential robust stability is presented. It is shown that the obtained result is different from or improves some existing ones reported in the literatures. Finally, some numerical examples and a simulation are given to show the effectiveness of the obtained result.

关键词： Neural networks Time-varying delays Global exponential robust stability

Elimination of Spatial Side-Channel Information for Compact Quantum Key Distribution Senders

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Journal of Electronic Science and Technology 2019年第3期17卷 195-203页

作者： Wei-shao huang Wei Zhang Yi-Dong huang the Department of Electronic Engineering Tsinghua UniversityBeijing 100084 the Beijing National Research Center for Information Science and Technology the Beijing Innovation Center for Future Chipsand also the Department of Electronic EngineeringTsinghua UniversityBeijing 100084 Frontier Science Center for Quantum Information Beijing 100084 Beijing Academy of Quantum Information Sciences Beijing 100193

For a compact quantum key distribution (QKD) sender for the polarization encoding BB84 protocol, an eavesdropper could take a side-channel attack by measuring the spatial information of photons to infer their polarizations. The possibility of this attack can be reduced by introducing an aperture in the QKD sender, however, the effect of the aperture on the QKD security lacks of quantitative analysis. In this paper, we analyze the mutual information between the actual keys encoded at this QKD sender and the inferred keys at the eavesdropper (Eve), demonstrating the effect of the aperture to eliminate the spatial side-channel information quantitatively. It shows that Eve’s potential on eavesdropping spatial side-channel information is totally dependent on the optical design of the QKD sender, including the source arrangement and the aperture. The height of compact QKD senders with integrated light-emitting diode (LED) arrays could be controlled under several millimeters, showing great potential on applications in portable equipment.

关键词： Diffraction-limited imaging system mutual information quantum key distribution spatial side-channel information

Crowdsourcing aggregation with deep Bayesian learning

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Science China(Information Sciences) 2021年第3期64卷 46-56页

作者： shao-Yuan LI Sheng-Jun huang Songcan CHEN College of Computer Science and Technology College of Artificial IntelligenceNanjing University of Aeronautics and Astronautics State Key Laboratory for Novel Software Technology Nanjing University

In this study, we consider a crowdsourcing classification problem in which labeling information from crowds is aggregated to infer latent true labels. We propose a fully Bayesian deep generative crowdsourcing model(Bayes DGC), which combines the strength of deep neural networks(DNNs) on automatic representation learning and the interpretable probabilistic structure encoding of probabilistic graphical models. The model comprises a DNN classifier as a prior for the true labels and a probabilistic model for the annotation generation process. The DNN classifier and annotation generation process share the latent true label variables. To address the inference challenge, we developed a natural-gradient stochastic variational inference, which combines variational message passing for conjugate parameters and stochastic gradient descent for DNN and learns the distribution of latent true labels and workers’ confusion matrix via end-to-end training. We illustrated the effectiveness of the proposed model using empirical results on 22 real-world datasets.

关键词： crowdsourcing classification fully Bayesian deep generative models natural gradient stochastic variational inference

Temperature dependence of Lüders strain and its correlation with martensitic transformation in a medium Mn transformation-induced plasticity steel

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Journal of Iron and Steel Research International 2017年第11期24卷 1073-1077页

作者： Xiao-gang Wang Ming-xin huang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College ot Mechanical and Vehicle EngmeermgHunan UniversityChangsha 410082HunanChina Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina

The Luders deformation behavior in a medium Mn transformation induced plasticity （TRIP） steel is investigated at different temperatures ranging from 25 to 300 ℃. It demonstrates that the Ltiders band appears at all testing temperatures but with varied Luders strains which do not change monoton ically with temperature. The martensitic transformation is simultaneously observed within the Ltiders band in varying degrees depending on the testing temperature. It is well verified that the martensitic transformation is not responsible for the formation of Luders band, and a reasonable explanation is given for the non-monotonic variation of Luders strain with increasing temperature.

关键词： Medium Mn steel TRIP effect Luders band Plastic instability Martensitic transformation

Distribution of Reference Stations: Initial Explore on the Optimal Selection Strategy

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Chinese Journal of Electronics 2021年第4期30卷 752-758页

作者： BAO Junjie LI Rui shao Bo huang Zhigang School of Electronic and Information Engineering Beihang University The 20th Research Institute of China Electronics Technology Group Corporation

The Satellite-based augmentation system(SBAS) is intended to provide real-time differential global navigation satellite system corrections with the high accuracy, availability, and integrity required for aviation applications. Since the performance of Satellite clock and ephemeris(SCE) corrections and Ionospheric range delay(IRD) corrections can vary dramatically depending on satellites and Ground reference stations(GRSs) geometry,therefore, we present a GRSs distribution optimized criteria and process to improve SBAS corrections *** present step-by-step optimized scheme using the average satellite surveillance dilution of precision and relative centroid metric availability of grid points as fitness values to determine the appropriate GRSs distribution to sufficiently meet the corrections requirements. The results show that the statistical mean RCM availability can reach more than 0.5518 for all IGPs and the coverage depth of GRSs in China and its surrounding areas is more than 25,which fully satisfies the requirement for solving SCE and IRD corrections.

关键词： Ground reference stations distribution Satellite surveillance dilution of precision Relative centroid metric Clock and ephemeris corrections Ionospheric corrections

A TDMA Approach for OFDM-Based Multiuser RadCom Systems

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China Communications 2023年第5期20卷 93-103页

作者： Yixuan huang Su Hu gang Wu National Key Laboratory on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

This paper is focused on the multiuser implementation of fusion of radar and communication(RadCom)in internet-of-vehicles(IoV)*** time-division multiple access(TDMA)technology degrades the velocity detection performance of orthogonal frequency-division multiplexing(OFDM)-based RadCom *** propose a new TDMA approach for OFDM-based RadCom systems,where multiuser communication and radar detection are completed *** consider a continuous-wave TDMA OFDM structure in which random user data or Zadoff-Chu(ZC)sequences are transmitted in one symbol duration to ensure detection *** an application of interference cancellation method,user data demodulation and environment sensing can be simultaneously accomplished by our proposed *** carry out numerical evaluation and show wireless communication and radar detection performance over the continuous-wave TDMA OFDM-based RadCom approach.

关键词： RadCom time-division multiple access(TDMA) orthogonal frequency-division multiplexing(OFDM) internet-of-vehicles(IoV)

Innate immune responses in RNA viral infection

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Frontiers of Medicine 2021年第3期15卷 333-346页

作者： Qian Xu Yuting Tang gang huang Divisions of Pathology and Experimental Hematology and Cancer Biology Cincinnati Children’s Hospital Medical CenterCincinnatiOH 45229USA Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

RNA viruses cause a multitude of human diseases,including several pandemic events in the past *** viral invasion,the innate immune system responds rapidly and plays a key role in activating the adaptive immune *** the innate immune system,the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral ***,dendritic cells,and natural killer cells are the principal innate immune components that exert antiviral *** this review,the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly *** the main role of immune cells in combating viral infection,the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was *** knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.

关键词： innate immune viral infection intercellular signaling metabolic changes epigenetic changes

Deep learning-based local climate zone classification using Sentinel-1 SAR and Sentinel-2 multispectral imagery

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Geo-Spatial Information Science 2022年第3期25卷 383-398页

作者： Lin Zhou Zhenfeng shao Shugen Wang Xiao huang School of Remote Sensing and Information Engineering Wuhan UniversityWuhanChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Department of Geosciences University of ArkansasFayettevilleNCUSA

As a newly developed classification system,the LCZ scheme provides a research framework for Urban Heat Island(UHI)studies and standardizes the worldwide urban temperature *** the growing popularity of deep learning,deep learning-based approaches have shown great potential in LCZ *** major cities in China are selected as the study *** this study,we design a deep convolutional neural network architecture,named Residual combined Squeeze-and-Excitation and Non-local Network(RSNNet),that consists of the Squeeze-and-Excitation(SE)block and non-local block to classify LCZ using freely available Sentinel-1 SAR and Sentinel-2 multispectral *** Accuracy(OA)of 0.9202,0.9524 and 0.9004 for three selected cities are obtained by applying RSNNet and training data of individual city,and OA of 0.9328 is obtained by training RSNNet with data from all three *** outperforms other popular Convolutional Neural Networks(CNNs)in terms of LCZ mapping *** further design a series of experiments to investigate the effect of different characteristics of Sentinel-1 SAR data on the performance of RSNNet in LCZ *** results suggest that the combination of SAR and multispectral data can improve the accuracy of LCZ *** proposed RSNNet achieves an OA of 0.9425 when integrat-ing the three decomposed components with Sentinel-2 multispectral images,2.44%higher than using Sentinel-2 images alone.

关键词： Local Climate Zone(LCZ) deep learning Sentinel-1 Sentinel-2