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The Study of Image Segmentation Based on the Combination of the Wavelet Multi-scale Edge Detection and the Entropy Iterative Threshold Selection

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Chinese Journal of Biomedical Engineering(English Edition) 2013年第4期22卷 154-160页

作者： ZHANG Qian HE Jian-feng MA lei PAN Li-peng LIU Jun-qing chen hong-lei Kunming University of Science and Technology Institute of Information Engineering and Automation

This paper proposes an image segmentation method based on the combination of the wavelet multi-scale edge detection and the entropy iterative threshold *** for segmentation is divided into two parts by high- and *** the high-frequency part the wavelet multiscale was used for the edge detection,and the low-frequency part conducted on segmentation using the entropy iterative threshold selection *** the consideration of the image edge and region,a CT image of the thorax was chosen to test the proposed method for the segmentation of the *** results show that the method is efficient to segment the interesting region of an image compared with conventional methods.

关键词： wavelet multi-scale entropy iterative threshold lung images

Multiplicity of solutions for the semilinear subelliptic Dirichlet problem

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Science China Mathematics 2024年第3期67卷 475-504页

作者： Hua chen hong-Ge chen Jin-Ning Li Xin Liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈C(Ω×R),g(x,u)is a Carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth *** the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the Morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem ***,we discuss the difference between the eigenvalue estimate approach and the Morse index approach in degenerate *** with the classical elliptic cases,both approaches here have their own strengths in the degenerate *** new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method Morse index

Balancing electron transfer and intermediate adsorption ability of metallic Ni-Fe-RE-P bifunctional catalysts via 4f-2p-3d electron interaction for enhanced water splitting

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Journal of Energy Chemistry 2024年第7期94卷 458-465页

作者： hong-Rui Zhao cheng-Zong Yuan chenliang Zhou Wenkai Zhao Lunliang Zhang Cong-Hui Li lei Xin Fuling Wu Shufeng Ye Xiaomeng Zhang Yunfa chen School of Rare Earths University of Science and Technology of ChinaHefei 230026AnhuiChina Jiangxi Province Research Institute of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119JiangxiChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking efficient ***,one efficient and universal strategy is developed to greatly regulate electronic structures of the metallic Ni-Fe-P catalysts via in-situ introducing the rare earth(RE)atoms(Ni-Fe-RE-P,RE=La,Ce,Pr,and Nd).Accordingly,the as-prepared optimal Ni-Fe-Ce-P/CC self-supported bifunctional electrodes exhibited superior electrocatalytic activity and excellent stability with the low overpotentials of 247 and 331 mV at 100 mA cm^(-2) for HER and OER,*** the assembled electrolyzer,the Ni-Fe-Ce-P/CC as bifunctional electrodes displayed low operation potential of 1.49 V to achieve a current density of 10 mA cm^(-2),and the catalytic performance can be maintained for 100 *** results combined with density functional theory(DFT)calculation reveal that Ce doping leads to electron decentralization and crystal structure distortion,which can tailor the band structures and d-band center of Ni-Fe-P,further increasing conductivity and optimizing intermediate adsorption *** work not only proposes a valuable strategy to regulate the electron transfer and intermediate adsorption of electrocatalysts via RE atoms doping,but also provides a deep under-standing of regulation mechanism of metallic electrocatalysts for enhanced water splitting.

关键词： RE atoms Electron transfer Adsorption energy Oxygen evolution Hydrogen evolution

Total suprarenal aortic occlusion with cardiac disease: a case series of three cases

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World Journal of Emergency Medicine 2024年第1期15卷 59-61页

作者： Yuanli lei Jiaozhen chen Qin chen Jiana Yin Weijia Huang Wenxing Song Shouquan chen Department of Emergency Medicine the First Affi liated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Electrocardiogram Wenzhou People's HospitalWenzhou 325000China

Acute aortic occlusion(AAO)has been very rarely reported in the literature and is a potentially life-threatening emergency.[1-5]AAO mostly occurs in cardiac disease patients,[1-4,6,7]and leads to cardiac complications.[1,2,5,6]Suprarenal aortic occlusion(SAO)is a very rare type of AAO,and infrarenal aortic occlusion(IAO)accounts for 75.8%-97.8%.[1,3,5-7]SAO is different from IAO in some clinical manifestations,treatment strategies,and prognoses.[3,6-8]SAO with cardiac disease will make the condition more complex and could easily cause a delay in diagnosis and portend worse outcomes with amputation and mortality rates.[1,3,6]Early and fast diagnosis and positive revascularization treatment are necessary to prevent cases from becoming fatal.[1-3]Herein,we present a case series of SAO with cardiac disease.

关键词： cardiac occlusion diagnosis

《民法典》视野下我国民族民事习惯的司法运用——基于235份裁判文书的分析

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华中科技大学学报（社会科学版） 2021年第5期35卷 114-122页

作者：陈洪磊吉林大学法学院

民族民事习惯是新时代基层社会治理的重要工具,借由司法裁判则是此种功能得以彰显的重要路径之一。对235份裁判文书的量化实证研究表明,民族民事习惯在裁判中的运用呈现稳中有增、领域分布广泛、层级下移等特点,发挥着“查明”“适用”... 详细信息

民族民事习惯是新时代基层社会治理的重要工具,借由司法裁判则是此种功能得以彰显的重要路径之一。对235份裁判文书的量化实证研究表明,民族民事习惯在裁判中的运用呈现稳中有增、领域分布广泛、层级下移等特点,发挥着“查明”“适用”“解释”三个层次的司法功能;同时也表现出一定的自发性与任意性,如运用方法缺位、运用条件模糊、运用程序欠缺等。为了保障民族民事习惯司法适用的科学性、统一性与准确性,应当供给克服适用障碍的有效方法:一是确定识别标准,民族民事习惯应当符合外观标准与合理性标准,合乎公序良俗与社会主义核心价值观;二是厘清适用位阶,民族民事习惯应当优先于《民法典》中的任意性规范,但其适用顺序应当在《民法典》强制性规范之后;三是完善程序规则,法官应当对民族民事习惯进行积极回应与审查,增强裁判路径的“可接受性”。

关键词：民族民事习惯司法运用民法典司法功能基层治理

Controlled fluorescent switch based on a cation grease/brake rotor system of pillar[5]arene

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Chinese Chemical Letters 2024年第3期35卷 5-7页

作者： Wei-lei Zhou Siwei Wang Yong chen College of Chemistry and Material Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional MoleculesInnovation Team of Optical Functional Molecular DevicesInner Mongolia Minzu UniversityTongliao 028000China College of Chemistry Nankai UniversityTianjin 300071China

In recent years,molecular shuttles,motors,pumps,and elevators,*** specifically respond external physical or chemical stimuli including light,temperature,pH,redox,solvent and chemical additive to change the structure a... 详细信息

关键词： additive system showing

A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics

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Petroleum Science 2024年第1期21卷 327-342页

作者： Qian Zhang Wen-Dong Wang Yu-Liang Su Wei chen Zheng-Dong lei lei Li Yong-Mao Hao Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Oil Development Branch Changqing Oilfield CompanyPetroChinaQingyang745708GansuChina PetroChina Research Institute of Petroleum Exploration&Development Beijing100083China

A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation.

关键词： Multi-scale coupled flow Stress sensitivity Shale oil Micro-scale effect Fractal theory

Near-zero-adhesion-enabled intact wafer-scale resist-transfer printing for high-fidelity nanofabrication on arbitrary substrates

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International Journal of Extreme Manufacturing 2024年第1期6卷 313-326页

作者： Zhiwen Shu Bo Feng Peng Liu lei chen Huikang Liang Yiqin chen Jianwu Yu Huigao Duan College of Mechanical and Vehicle Engineering National Engineering Research Centre for High Efficiency GrindingHunan UniversityChangsha 410082People’s Republic of China Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300People’s Republic of China School of Mechanical Engineering Hunan University of Science and TechnologyXiangtan 411201People’s Republic of China Shenzhen Research Institute Hunan UniversityShenzhen 518000People’s Republic of China

There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,and fexible *** direct-lithography methods are difficult to use on fexible,nonplanar,and biocompatible ***,this fabrication is usually accomplished by nanotransfer ***,large-scale integration of multiscale nanostructures with unconventional substrates remains challenging because fabrication yields and quality are often limited by the resolution,uniformity,adhesivity,and integrity of the nanostructures formed by direct ***,we proposed a resist-based transfer strategy enabled by near-zero adhesion,which was achieved by molecular modification to attain a critical surface energy *** approach enabled the intact transfer of wafer-scale,ultrathin-resist nanofilms onto arbitrary substrates with mitigated cracking and wrinkling,thereby facilitating the in situ fabrication of nanostructures for functional *** this approach,fabrication of three-dimensional-stacked multilayer structures with enhanced functionalities,nanoplasmonic structures with~10 nm resolution,and MoS2-based devices with excellent performance was demonstrated on specific *** results collectively demonstrated the high stability,reliability,and throughput of our strategy for optical and electronic device applications.

关键词： resist-based transfer printing near-zero adhesion critical surface energy wafer-scale nanofabrication in situ fabrication optoelectronic devices

Unveiling size-fluorescence correlation of organic nanoparticles and its use in nanoparticle size determination

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Aggregate 2024年第1期5卷 331-336页

作者： Wu-Jie Guo Shixiang Ma Hui Wang Lu Qiao lei chen chenyu hong Bin Liu Xiaoyan Zheng Hui-Qing Peng State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electro-photonic Conversion MaterialsKey Laboratory of Medicinal Molecule Science and Pharmaceutics Engineering of Ministry of Industry and Information TechnologySchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijingChina

Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing on organic FNPs has not been achieved to ***,we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene-based bis-ureidopyrimidinone monomers(bis-UPys)to relate the size to the fluorescence of organic *** an equal concentration of bis-UPys,a logarithmic relationship between them is built with a correlation coefficient higher than *** calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the *** leads to different nonradiative decay rates of the embedded and exposed bis-UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface *** established fluorescence intensity-size correlation possesses fine universality and reliability,and it is successfully utilized to estimate the sizes of other nanoparticles,including those in highly diluted dispersions of *** work paves a new way for the simple and real-time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.

关键词： aggregation-induced emission fluorescence detection fluorescent nanoparticle nanoparticle size supramolecular polymer