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Semi-supervised dictionary learning with label propagation for image classification

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Computational Visual Media 2017年第1期3卷 83-94页

作者： lin Chen Meng Yang College of Computer Science and Software Engineering Shenzhen UniversityShenzhenChina School of Data and Computer Science Sun Yat-sen UniversityGuangzhouChina Key Laboratory of Machine Intelligence and Advanced Computing(sun Yat-sen University) Ministry of EducationChina

Sparse coding and supervised dictionary learning have rapidly developed in recent years,and achieved impressive performance in image classification. However, there is usually a limited number of labeled training samples and a huge amount of unlabeled data in practical image classification,which degrades the discrimination of the learned dictionary. How to effectively utilize unlabeled training data and explore the information hidden in unlabeled data has drawn much attention of researchers. In this paper, we propose a novel discriminative semisupervised dictionary learning method using label propagation(SSD-LP). Specifically, we utilize a label propagation algorithm based on class-specific reconstruction errors to accurately estimate the identities of unlabeled training samples, and develop an algorithm for optimizing the discriminative dictionary and discriminative coding vectors *** experiments on face recognition, digit recognition, and texture classification demonstrate the effectiveness of the proposed method.

关键词： semi-supervised learning dictionary learning label propagation image classification

Liver-resident NK cells and their potential functions

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Cellular & Molecular Immunology 2017年第11期14卷 890-894页

作者： Hui Peng Rui sun Institute of Immunology and The CAS Key Laboratory of Innate Immunity and Chronic Disease School of Life Sciences and Medical CenterUniversity of Science and Technology of ChinaHefeiAnhui 230027China

Natural killer(NK)cells represent a heterogeneous population of innate lymphocytes with phenotypically and functionally distinct *** particular,recent studies have identified a unique subset of NK cells residing within the liver that are maintained as tissue-resident cells,confer antigen-specific memory responses and exhibit different phenotypical and developmental characteristics compared with conventional NK(cNK)*** findings have encouraged researchers to uncover tissue-resident NK cells at other sites,and detailed analyses have revealed that these tissue-resident NK cells share many similarities with liver-resident NK cells and tissue-resident memory T ***,we present a brief historical perspective on the discovery of liver-resident NK cells and discuss their relationship to cNK cells and other emerging NK cell subsets and their potential functions.

关键词： potential maintained finding

Glycyrrhizic acid based self-assembled helical nanostructures as scaffolds for asymmetric Diels-Alder reaction

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Chinese Chemical Letters 2019年第5期30卷 966-968页

作者： Yimeng sun Yan Meng Jian Jiang Hui sun Tiesheng Li College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China National Centre for Nanoscience and Technology Beijing 100190China

Glycyrrhizic acid(GA),as a traditional herbal,can self-assemble into helical nanofiber in the *** formed helical nanostructures can be employed as scaffolds for asymmetric Diels-Alder *** co-assembling with a series of achiral copper-ligands,the chirality of GA helical nanostructures can be transferred to catalytic site,and resulted assemblies showed moderated enantioselectivity toward catalysis of Diels-Alder reaction.

关键词： Glycyrrhizic acid Helical nanofiber Co-assembly Asymmetric catalysis Diels-Alder reaction

GRACE time-variable gravity and its application to geoscience:Quantitative analysis of relevant literature

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Earth and Planetary Physics 2023年第2期7卷 295-309页

作者： Cao Liu WenKe sun College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China

The Gravity Recovery and Climate Experiment(GRACE)is the most important gravity satellite to date in human *** its launch in 2002,GRACE time-varying gravity has had an unprecedented impact on earth science and has generated revolutionary *** of natural phenomena such as climate warming,glacial melting,sea level rise,and earthquakes,earth science research has become an increasingly popular discipline in recent *** article summarizes the importance of GRACE time-varying gravity,its application to geoscience,and its *** analyzed the historical development and current status of GRACE time-varying gravity as well as research hotspots by searching the literature in the core collection databases of the China National Knowledge Infrastructure and the Web of Science over the past 20 *** CiteSpace and VOSviewer software packages were applied with reference to the principle of literature *** investigation and analysis of characteristic indexes,such as the numbers of publications,co-occurrence of keywords,and co-citation of documents,uncovered the wide application and promotion of gravity satellites,especially GRACE time-varying gravity,in earth *** results showed that the number of publications addressing GRACE data and time-varying gravity theory is increasing annually and that the USA,China,and Germany are the main *** Chinese Academy of Sciences,the National Aeronautics and Space Administration of the United States,and the Helmholtz Association of German Research Centres rank among the top three institutions in the world in terms of producing the most publications on this *** found that GRACE time-varying gravity plays unique roles in measuring changes in terrestrial water storage changes,ice and snow melting and sea level changes,and(co)seismic gravity changes,as well as in promoting other disciplines.

关键词： Gravity Recovery and Climate Experiment(GRACE) Gravity Recovery and Climate Experiment Follow-On(GRACE-FO) time-varying gravity bibliometry mass change CiteSpace VOSviewer

具有变消耗率的比率确定型chemostat模型渐近行为(英文)

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大连理工大学学报 2007年第6期47卷 931-936页

作者：孙树林陈兰荪大连理工大学应用数学系

为了使微生物培养的理论研究更接近于实验,建立了一个具有变消耗率的比率确定型chemostat模型.这个模型推广了经典的Monod模型,而且假定了消耗率是一个营养基的线性函数,微生物增长率是比率确定型函数.对该模型作了定性分析,证明了只要... 详细信息

为了使微生物培养的理论研究更接近于实验,建立了一个具有变消耗率的比率确定型chemostat模型.这个模型推广了经典的Monod模型,而且假定了消耗率是一个营养基的线性函数,微生物增长率是比率确定型函数.对该模型作了定性分析,证明了只要正平衡点存在系统就是持续生存的.同时也给出了系统极限环存在和正平衡点全局渐近稳定的充分条件.

关键词： chemostat模型连续培养比率确定持续生存极限环

A NOTE ON THE LIMITING STRENGTH OF A CLOSE-COILED HELICAL SPRING

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物理学报 1955年第1期 34-36页

作者： lin HUNG-sun (Institute of Mathematics, Academia Sinica)

The problem of twist of a circular ring sector is considerd.A ring sector with circularcross section is under the action of two equal and opposite forces along the axis throughthe center of the *** forces produce the same torque in all cross sections of thering（see fig.）.The forces are assumed to be large enough as to bring the entire crosssection into a plastic *** equation of equilibrium in stresses to be satisfied isand the yield condition is assumed to be (τrθ)2+(τθx)2=K2where K is a *** surface of the ring sector is free from traction.

关键词： A NOTE ON THE LIMITING STRENGTH OF A CLOSE-COILED HELICAL SPRING

Traumatic brain injury Nature and genetic influences

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Neural Regeneration Research 2008年第7期3卷 786-790页

作者： Yong Jiang Xiaochuan sun Department of Neurosurgery the First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China Department of Neurosurgery the First Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China

At present, much evidence indicates that TBI is similar in pathology and severity during the acute stage, yet may result in varied outcomes. Known prognostic factors, such as age and severity of injury and treatments, only partially explain this variability. In addition, it has been demonstrated that genetic polymorphisms may play an important role in TBI susceptibility, as well as outcome following TBI.

关键词： traumatic brain injury prognostic factor genetic factor

Effects of material of metallic frame on the penetration resistances of ceramic-metal hybrid structures

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Defence Technology（防务技术） 2020年第1期16卷 77-87页

作者： Xuanyi An Chao Tian Qitian sun Yongxiang Dong State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The effects of metallic material on the penetration resistances of ceramic-metal hybrid structures against vertical long-rod tungsten projectiles were studied by artillery-launched experiments and numerical *** structures with rectangular cores in transverse orthogonal arrangement and slidefitting ceramic inserts of zirconia toughened alumina prisms were fabricated with titanium alloy TC4(Ti6 Al4 V),AISI 4340 steel and 7075 aluminum alloy panels,*** results showed that the hybrid structure of Ti6A14V exhibited the highest penetration resistance,followed by that of 7075 aluminum alloy with the same area *** penetration resistance of the hybrid structure of AISI4340 steel was the *** underlying mechanisms showed that the metallic material of a ceramicmetal hybrid structure can directly affect its energy absorption from the impact projectile,which further affects its penetration *** metallic frames exhibited different failure characteristics,resulting in different constraint conditions or support conditions for ceramic *** high penetration resistance of the Ti6Al4V hybrid structure was due to its stronger back support to ceramic prisms as compared with that of AISI 4340 steel hybrid structure,and better constraint condition for ceramic prisms by metallic webs as compared with that of 7075 aluminum alloy hybrid *** results of mass efficiency and thickness efficiency showed that the Ti6Al4V hybrid structure has advantages in reducing both the thickness and the mass of protective *** addition,because the ceramic-metal hybrid structures in the present work were heterogeneous,impact position has slight influence on their penetration resistances.

关键词： Hybrid structures Zirconia toughened alumina Penetration resistance Long-rod projectile Metallic frame

Distributed CI Fusion Estimation for Non-uniform Sampling Systems with Fading Measurements

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Distributed CI Fusion Estimation for Non-uniform Sampling Sy...