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Absence Importance and Its Application to Feature Detection and Matching

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International Journal of Automation and computing 2016年第5期13卷 480-490页

作者： Zhi-Heng Wang Qin-Feng Song Hong-Min Liu zhan-qiang huo School of Computer Science and Technique Henan Polytechnic University

Feature detection and matching play important roles in many fields of computer vision, such as image understanding, feature recognition, 3D-reconstruction, video analysis, etc. Extracting features is usually the first step for feature detection or matching, and the gradient feature is one of the most used selections. In this paper, a new image feature-absence importance （AI） feature, which can directly characterize the local structure information, is proposed. Greatly different from the most existing features, the proposed absence importance feature is mainly based on the consideration that the absence of the important pixel will have a great effect on the local structure. Two absence importance features, mean absence importance （MAI） and standard deviation absence importance （SDAI）, are defined and used subsequently to construct new algorithms for feature detection and matching. Experiments demonstrate that the proposed absence importance features can be used as an important complement of the gradient feature and applied successfully to the fields of feature detection and matching.

关键词： Absence importance （AI） feature detection feature matching mean absence importance （MAI） standard deviation absence importance （SDAI）.

Image Inpainting Based on Structural Tensor Edge Intensity Model

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International Journal of Automation and computing 2021年第2期18卷 256-265页

作者： Jing Wang Yan-Hong Zhou Hai-Feng Sima zhan-qiang huo Ai-Zhong Mi College of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454003China

In the exemplar-based image inpainting approach,there are usually two major problems:the unreasonable calculation of priority and only considering the color features in the patch lookup strategy.In this paper,we propose an image inpainting approach based on the structural tensor edge intensity model.First,we use the progressive scanning inpainting method to avoid the image filling order being affected by the priority function.Then,we use the edge intensity model to build the patches similarity function for correctly identifying the local image structure.Finally,the balance operator is used to restrict the excessive propagation of structural information to ensure the correct structural reconstruction.The experimental results show that the our approach is comparable and even superior to some state-of-the-art inpainting algorithms.

关键词： Exemplar-based technique image inpainting structural tensor edge intensity model structure propagation balance operator

Gelfand-Kirillov Dimension and Reducibility of Scalar Generalized Verma Modules for Classical Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 658-706页

作者： zhan qiang BAI Jing JIANG School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China E-mail:zqbai@*** jjsd6514@***

Let g be a classical complex simple Lie algebra and q be a parabolic subalgebra.Let M be a generalized Verma module induced from a one dimensional representation of q.Such M is called a scalar generalized Verma module.In this paper,we will determine the reducibility of scalar generalized Verma modules associated to maximal parabolic subalgebras by computing explicitly the Gelfand-Kirillov dimension of the corresponding highest weight modules.

关键词： Generalized Verma module Gelfand-Kirillov dimension Young tableau

Irreducible Representations of GL_(n)(C)of Minimal Gelfand-Kirillov Dimension

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Acta Mathematica Sinica,English Series 2024年第3期40卷 639-657页

作者： zhan qiang BAI Yang Yang CHEN Dong Wen LIU Bin Yong SUN School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China School of Sciences JiangnanUniversityWui214122P.R.China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058P.R.China Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China

In this article,by studying the Bernstein degrees and Goldie rank polynomials,we es-tablish a comparison between the irreducible representations of G=GL_(n)(C)possessing the minimal Gelfand-Kirillov dimension and those induced from finite-dimensional representations of the maximal parabolic subgroup of G of type(n-1,1).We give the transition matrix between the two bases for the corresponding coherent families.

关键词： Bernstein degree coherent continuation Gelfand-Kirillov dimension

Copper-catalyzed C(sp)-H aryl amination enables modular synthesis of quinolines and 2-quinolinones

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Science China Chemistry 2024年第2期67卷 595-603页

作者： Yang Gao Haixia Li Simin Yang Yanping huo Qian Chen Xianwei Li Zhe Wang Xiao-qiang Hu School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory Jieyang515200China Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science School of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan430074China

Herein,we disclose a novel copper-catalyzed C(sp)-H aryl amination of terminal alkynes with anthranils,enabling the rapid generation of highly reactive secondary N-aryl ynamines for the modular synthesis of structurally diverse C2-substituted quinolines and 2-quinolinones.The in-situ formed carbonyl-ynamines are prone to tautomerize to carbonyl-ketenimines,which can efficiently react with a series of nucleophiles,including amines,alcohols,phenols,thiols,thiophenols,active-methylene compounds,and even water to produce various quinoline derivatives with the generation of H_(2)O as a sole and green byproduct.This method also unlocks a practical route to create various quinoline-fused heterocycles and can be successfully applied to the late-stage modification of complex molecules and the concise synthesis of bioactive targets.Mechanistic studies reveal a coppercatalyzed inner-sphere nitrene transfer process by using anthranils as novel aryl nitrene precursors.

关键词： copper catalysis anthranils C(sp)-H aryl amination carbonyl-ketenimines quinolines

The mechanisms of thermal solidification agent promoting steam diversion in heavy oil reservoirs

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Petroleum Science 2024年第3期21卷 1902-1914页

作者： zhan-Xi Pang Qian-Hui Wang qiang Meng Bo Wang Dong Liu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Liaohe Oilfield Institute CNPC China Henan Oilfield Institute Sinopec China Tianjin Branch of China National Offshore Oil Company (CNOOC) Ltd.

At high cycles of steam huff & puff, oil distribution in reservoirs becomes stronger heterogeneity due to steam channeling. Thermal solidification agent can be used to solve this problem. Its solution is a lowviscosity liquid at normal temperature, but it can be solidified above 80°C. The plugging degree is up to 99% at 250°C. The sweep efficiency reaches 59.2%, which is 7.3% higher than pure steam injection. In addition, simultaneous injection of viscosity reducer and/or nitrogen foams can further enhance oil recovery. The mechanism of this technology depends on its strong plugging ability, which changes the flowing pattern of steam to effectively mobilize remaining oil. Viscosity reducer and nitrogen foams further expand the sweep range and extends the effective period. Therefore, thermal solidification agent can plug steam channeling paths and adjust steam flowing direction to significantly enhance oil recovery at high cycles of steam huff & puff.

关键词： Heavy oil reservoir Steam huff & puff Steam channeling Steam diversion Plugging performance Mechanism analysis

Low-rank matrix recovery with total generalized variation for defending adversarial examples

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 432-445页

作者： Wen LI Hengyou WANG Lianzhi huo qiang HE Linlin CHEN Zhiquan HE Wing W.Y.Ng School of Science Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen 518060China Institute of Big Data Modeling and Technology Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Low-rank matrix decomposition with first-order total variation(TV)regularization exhibits excellent performance in exploration of image structure.Taking advantage of its excellent performance in image denoising,we apply it to improve the robustness of deep neural networks.However,although TV regularization can improve the robustness of the model,it reduces the accuracy of normal samples due to its over-smoothing.In our work,we develop a new low-rank matrix recovery model,called LRTGV,which incorporates total generalized variation(TGV)regularization into the reweighted low-rank matrix recovery model.In the proposed model,TGV is used to better reconstruct texture information without over-smoothing.The reweighted nuclear norm and Li-norm can enhance the global structure information.Thus,the proposed LRTGV can destroy the structure of adversarial noise while re-enhancing the global structure and local texture of the image.To solve the challenging optimal model issue,we propose an algorithm based on the alternating direction method of multipliers.Experimental results show that the proposed algorithm has a certain defense capability against black-box attacks,and outperforms state-of-the-art low-rank matrix recovery methods in image restoration.

关键词： Total generalized variation Low-rank matrix Alternating direction method of multipliers Adversarial example

Flexible UV detectors based on in-situ hydrogen doped amorphous Ga_(2)O_(3) with high photo-to-dark current ratio

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Materials Futures

Materials Futures 2024年第1期3卷 181-189页

作者： Yanxin Sui Huili Liang Wenxing huo Xiaozhi zhan Tao Zhu Zengxia Mei Songshan Lake Materials Laboratory DongguanGuangdong 523808People’s Republic of China Institute of Physics Chinese Academy of SciencesBeijing 100190People’s Republic of China Department of Biomedical Engineering Tianjin University92 Weijin RoadTianjin 300072People’s Republic of China China Spallation Neutron Source DongguanGuangdong 523803People’s Republic of China

Amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))has been attracting more and more attention due to its unique merits such as wide bandgap(∼4.9 eV),low growth temperature,large-scale uniformity,low cost and energy efficient,making it a powerful competitor in flexible deep ultraviolet(UV)photodetection.Although the responsivity of the ever-reported a-Ga_(2)O_(3)UV photodetectors(PDs)is usually in the level of hundreds of A/W,it is often accompanied by a large dark current due to the presence of abundant oxygen vacancy(VO)defects,which severely limits the possibility to detect weak signals and achieve versatile applications.In this work,the VO defects in a-Ga_(2)O_(3)thin films are successfully passivated by in-situ hydrogen doping during the magnetron sputtering process.As a result,the dark current of a-Ga_(2)O_(3)UV PD is remarkably suppressed to 5.17×10^(-11) A at a bias of 5 V.Importantly,the photocurrent of the corresponding device is still as high as 1.37×10^(-3)A,leading to a high photo-to-dark current ratio of 2.65×107 and the capability to detect the UV light with the intensity below 10 nW cm^(-2).Moreover,the H-doped a-Ga_(2)O_(3)thin films have also been deposited on polyethylene naphtholate substrates to construct flexible UV PDs,which exhibit no great degradation in bending states and fatigue tests.These results demonstrate that hydrogen doping can effectively improve the performance of a-Ga_(2)O_(3)UV PDs,further promoting its practical application in various areas.

关键词： Ga_(2)O_(3) hydrogen doping ultraviolet photodetector photo-to-dark current ratio neutron reflection

A bibliometric analysis of molybdenum-based nanomaterials in the biomedical field

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Tungsten 2024年第1期6卷 17-47页

作者： Zhi-qiang Wang Ya-Wen Pan Jing Wu Hong-Bin Qi Shuang Zhu zhan-Jun Gu School of Science China University of GeosciencesBeijing 100083China CAS Key Laboratory for Biomedical Eff ects of Nanomaterials and Nanosafety Institute of High Energy PhysicsBeijing 100049China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of ChinaChinese Academy of SciencesBeijing 100190China College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China

Molybdenum(Mo)-based nanomaterials have been widely used in biomedical fields due to their various nanostructures and unique physical/chemical properties.Although various reviews have described the development of Mo-based materials in the biomedical field,an objective and comprehensive summary and analysis of research trends in this field is still rare.Therefore,we used the bibliometric analysis method to analyze all relevant literature on the biological application of Mobased nanomaterials in recent years.First,we use bibliometric tools to analyze the dataset by year,country/region,institution and research hotspot to obtain the research trends.Next,based on objectively identified research hotspots,the biomedical applications of Mo-based nanomaterials are reviewed comprehensively,mainly including sensors,cancer imaging/therapy and antibacterial applications.Finally,we discussed the application prospects and challenges of Mo-based materials.This article provides a new perspective to understand the current research progress and further promote the development of Mobased nanomaterials in biomedical research.

关键词： Molybdenum Nanomaterial Biomedicine Bibliometric analysis