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Scene text detection and recognition： recent advances and future trends

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Frontiers of Computer Science 2016年第1期10卷 19-36页

作者： Yingying ZHU Cong YAO xiang bai School of Electronic Information and Communications Huazhong University of Science and Technology Wuhan 430074 China

Text, as one of the most influential inventions of humanity, has played an important role in human life, so far from ancient times. The rich and precise information embod- ied in text is very useful in a wide range of vision-based ap- plications, therefore text detection and recognition in natu- ral scenes have become important and active research topics in computer vision and document analysis. Especially in re- cent years, the community has seen a surge of research efforts and substantial progresses in these fields, though a variety of challenges （e.g. noise, blur, distortion, occlusion and varia- tion） still remain. The purposes of this survey are three-fold： 1） introduce up-to-date works, 2） identify state-of-the-art al- gorithms, and 3） predict potential research directions in the future. Moreover, this paper provides comprehensive links to publicly available resources, including benchmark datasets, source codes, and online demos. In summary, this literature review can serve as a good reference for researchers in the areas of scene text detection and recognition.

关键词： text detection text recogntion natural image,algorithms applications

Prediction of room-temperature half-metallicity in layered halide double perovskites

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npj Computational Materials 2019年第1期5卷 132-139页

作者： Jian xu Changsong xu Jian-Bo Liu Laurent Bellaiche Hongjun xiang bai-Xin Liu Bing Huang Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Computational Science Research Center Beijing 100193China Physics Department and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Key Laboratory of Computational Physical Sciences(Ministry of Education) State Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China

Half-metallic ferromagnets(HMFs)that possess intriguing physical properties with completely spin-polarized current are key candidates for high-efficiency spintronic ***,HMFs that could simultaneously have high Curie temperature(Tc),wide half-metallic gap(ΔHM),and large bulk magnetocrystalline anisotropy energy(MAE)are very rare,which significantly restrict their room-temperature(RT)*** this article,through materials screening in layered halide double perovskites(LHDPs).

关键词： metallic perovskite halide

Simultaneous integration of Fe clusters and NiFe dual single atoms in nitrogen-doped carbon for oxygen reduction reaction

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Nano Research 2024年第4期17卷 2291-2297页

作者： Jirong bai Yuebin Lian Yaoyao Deng Mei xiang Peng xu Quanfa Zhou Yawen Tang Yaqiong Su Research Center of Secondary Resources and Environment School of Chemical Engineering and MaterialsChangzhou Institute of TechnologyChangzhou 213022China Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Chemistry Engineering Research Center of Energy Storage Materials and Devices of Ministry of EducationNational Innovation Platform(Center)for Industry-Education Integration of Energy Storage TechnologyXi’an Jiaotong UniversityXi’an 710049China

Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordination environment of the Fe site and optimizing the binding energy of oxygen reduction intermediates are effective strategies to optimize ORR ***,we report a new method in which Ni is introduced to construct NiFe dual single atoms and iron nanoclusters loaded on the nitrogen-doped carbon with a highly porous *** design plays a synergistic role of dual single atoms and clusters,optimizes the 3d orbital and Fermi level of Fe,breaks the symmetrical structure of Fe-N_(4),and effectively improves the adsorption/desorption behavior of the oxygen-containing *** tests show FeNCs/NiFeSAs-NC has an excellent intrinsic *** calculations show the oxygen-containing species on the Ni active site will move to the middle of NiFe(bridge site connection)after optimization and that the key step is OH desorption,with a reaction energy of 0.27 *** electron exchange between NiFe-N6 and Fe-cluster is very strong,further indicating the introduction of Ni species and Fe clusters has a regulatory effect on the electronic structure of Fe-N_(4).

关键词： NiFe dual single atoms Fe clusters OH*adsorption energy oxygen reduction reaction

Theoretical analyses on hydrodynamic instability in narrow deep river with variable curvature

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Applied Mathematics and Mechanics(English Edition) 2015年第9期36卷 1147-1168页

作者： Haijue xu Yuchuan bai State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Institute for Sedimentation on River and Coastal Engineering Tianjin University

Bending river is the most common river type in nature, and it is also a typical example for river evolution. The transform of the flow pattern can affect the development of the riverbed form. In return, the variation in the riverbed form can affect the hydrodynamic characteristics of the flow, thereby leading to the continuous evolution of the bending river. Based on this, a theoretical model for the bending river is established. The hydrodynamic instability characteristics of the laminar flow in the channel with a variable curvature, a typical and the variations of some parameters such wave frequency are also discussed. model as the meandering river, are studied, as the curvature, the wave number, and the

关键词： bending river hydrodynamic stability self-adaptability nonlinear riverdynamics

Investigation of a complete squeeze-film damping model for MEMS devices

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Microsystems & Nanoengineering 2021年第4期7卷 67-79页

作者： Qianbo Lu Weidong Fang Chen Wang Jian bai Yuan Yao Jiaxiao Chen xiang xu Wei Huang Ningbo Institute of Northwestern Polytechnical University Frontiers Science Center for Flexible Electronics(FSCFE)MIIT Key Laboratory of Flexible Electronics(KLoFE)Shaanxi Key Laboratory of Flexible Electronics(KLoFE)Institute of Flexible Electronics(IFE)Northwestern Polytechnical University710072 Xi'anShaanxiChina College of Optical Science and Engineering State Key Laboratory of Modern Optical InstrumentationZhejiang University310027 HangzhouChina Department of Electrical Engineering and Computer Science University of LiegeLiegeBelgium ESAT-MNS University of Leuven3001 LeuvenBelgium Huazhong University of Science and Technology-Wuhan National Laboratory for Optoelectronics 430074 HubeiChina Huazhong Institute of Electro-Optics-Wuhan National Lab for Optoelectronics 430074 HubeiChina

Dynamic performance has long been critical for micro-electro-mechanical system(MEMS)devices and is significantly affected by *** structural vibration conditions lead to different damping effects,including border and amplitude effects,which represent the effect of gas flowing around a complicated boundary of a moving plate and the effect of a large vibration amplitude,*** models still lack a complete understanding of damping and cannot offer a reasonably good estimate of the damping coefficient for a case with both *** efforts have been undertaken to consider these two effects,yet a complete model has remained *** paper investigates the dynamic performance of vibrated structures via theoretical and numerical methods simultaneously,establishing a complete model in consideration of both effects in which the analytical expression is given,and demonstrates a deviation of at least threefold lower than current studies by simulation and experimental *** complete model is proven to successfully characterize the squeeze-film damping and dynamic performance of oscillators under comprehensive ***,a series of simulation models with different dimensions and vibration statuses are introduced to obtain a quick-calculating factor of the damping coefficient,thus offering a previously unattainable damping design guide for MEMS devices.

关键词： film complete offering

Theoretical Investigations on the Interaction Nature of Br_2 with HF, H_2O and NH_3

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Chinese Journal of Structural Chemistry 2007年第5期26卷 587-593页

作者： WU Wen-Sheng WANG Zhao-xu ZHENG bai-Shu SHU Hua LI xiang WU Jun-Yong Department of Light Industry and Chemistry Zhaoqing University Zhaoqing Guangdong 526061 China School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan Hunan 411201 China Institute of Modern Catalysis Beijing University of Chemical TechnologyState Key Laboratory of Chemical Resource Engineering Beijing 100029 China

The interactions of HF, H2O and NH3 with Br2 are investigated at the MP2（full）/ aug-cc-pVDZ level. It is found that two kinds of stable complexes, halogen-bonded and hydrogen-bonded complexes, exist between Br2 and HF and between Br2 and H2O. The interaction energy analysis and natural population analysis （NPA） are conducted to these two kinds of complexes, indicating the halogen-bonded complexes are more stable than the corresponding hydrogen-bonded ones, and the binding energies of the former increase in the order HFH2O for the latter.

关键词： MP2 intermolecular interaction halogen-bonded complex hydrogen-bondedcomplex NPA

Magnetic and electrical transport study of the intrinsic magnetic topological insulator MnBi_(2)Te_(4)with Ge doping

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Frontiers of physics 2024年第3期19卷 51-59页

作者： Qingwang bai Mingxiang xu School of Physics Southeast UniversityNanjing 211189China

As an intrinsic magnetic topological insulator with magnetic order and non-trivial topological structure,MnBi_(2)Te_(4)is an ideal material for studying exotic topological states such as quantum anomalous Hall effect and topological axion insulating ***,we carry out magnetic and electrical transport measurements on(Mn1–xGex)Bi_(2)Te_(4)(x=0,0.15,0.30,0.45,0.60,and 0.75)single *** is found that with increasing x,the dilution of magnetic moments gradually weakens the antiferromagnetic exchange ***,Ge doping reduces the critical field of ferromagnetic ordering,which may provide a possible way to implement the quantum anomalous Hall effect at lower magnetic *** transport measurements suggest that electrons are the dominant charge carriers,and the carrier density increases with the Ge doping ***,the Kondo effect is observed in the samples with x=0.45,0.60,and *** results suggest that doping germanium is a viable way to tune the magnetic and electrical transport properties of MnBi_(2)Te_(4),opening up the possibility of future applications in magnetic topological insulators.

关键词： MnBi_(2)Te_(4) intrinsic magnetic topological insulator transition points Kondo effect

Target searching based on modified implicit ROI encoding scheme

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Journal of Systems Engineering and Electronics 2008年第5期19卷 888-892页

作者： bai xu Zhang Zhongzhao Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China

An EBCOT-based method is proposed to reduce the priority of background coefficients in the ROI code block without compromising algorithm complexity. The region of interest is encoded to a higher quality level than background, and the target searching time in video-guided penetrating missile can be shortened. Three kinds of coding schemes based on EBCOT are discussed. Experimental results demonstrate that the proposed method shows higher compression efficiency, lower complexity, and good reconstructed ROI image quality in the lower channel capacity.

关键词： video-guided penetrating bomb implicit ROI EBCOT.

Isothermal Kinetics Modelling of the Fischer-Tropsch Synthesis over the Spray-Dried Fe-Cu-K Catalyst

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Journal of Natural Gas Chemistry 2006年第2期15卷 105-114页

作者： Xiaohui Guo Ying Liu Jie Chang Liang bai Yuanyuan xu Hongwei xiang Yongwang Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China Graduate University of Chinese Academy of Sciences Beijing 100039 China

The isothermal kinetics of the Fischer-Tropsch synthesis （FTS） over Fe-Cu-K spray-dried catalyst was studied in a spinning basket reactor. The experiments were carried out at a constant temperature of 523 K, n（H2）/n（CO） feed ratios of 0.8 2.0, reactor pressures of 1.1 2.5 MPa, and space velocity of 0.556× 10^-3 Nm^3/kgcat·s. Kinetic model for hydrocarbon formation was derived on the basis of simplified carbide mechanism to reduce the number of parameters. Two individual rate constants for methane and ethene were considered. Furthermore, the model was modified empirically by non-intrinsic effect, such as physisorption and fictitious olefin pressures that were taken into account, and the influences of secondary reaction of α-olefins on product distribution. The simulation results showed that the experimental phenomena of FTS and the deviations from ASF distribution, such as the relatively high yield of methane and low yield of ethene observed experimentally could be depicted basically.

关键词： Fischer-Tropsch synthesis isothermal kinetics non-intrinsic effect spray-dried catalyst iron copper kalium