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Drogue detection for autonomous aerial refueling via hybrid pigeon-inspired optimized color opponent and saliency aggregation

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Chinese Journal of Aeronautics 2024年第5期37卷 27-38页

作者： Tongyan WU Haibin DUAN Yanming FAN State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China Virtual Reality fundamental Research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China AVIC Shenyang Aircraft Design and Research institute Shenyang 110035China

Drogue detection is one of the challenging tasks in autonomous aerial refueling due to the requirement for accuracy and *** detection based on image intrinsic cues can achieve fast detection,but with poor *** studies reveal that optimization-based methods provide accurate and quick solutions for saliency *** paper presents a hybrid pigeon-inspired optimization method,the optimized color opponent,that aims to adjust the weight of color opponent channels to detect the drogue *** can optimize the weights in the selected aerial refueling scene offline,and the results are applied for drogue detection in the scene.A novel algorithm aggregated by the optimized color opponent and robust background detection is presented to provide better precision and *** results on benchmark datasets and aerial refueling images show that the proposed method successfully extracts the saliency region or drogue and exhibits superior performance against the other saliency detection methods with intrinsic *** algorithm designed in this paper is competent for the drogue detection task of autonomous aerial refueling.

关键词： Autonomous aerial refueling Drones Hybrid pigeon-inspired optimization Color opponent Saliency detection Saliency aggregation

Structural and luminescence studies of europium ions in lithium aluminium borophosphate glasses

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Journal of Rare Earths 2014年第7期32卷 585-592页

作者： Poh Sum Wong Ming Hua Wan Rosli Hussin Hendrik O.Lintang Salasiah Endud Phosphor Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia ibnu sina institute for fundamental science studies Universiti Teknologi Malaysia Department of Chemistry Faculty of ScienceUniversiti Teknologi Malaysia

Eu3＋ doped borophosphate glasses with the chemical composition 20Li2O-30Al2O3-10B2O3-40P2O5-xEu2O3（where x=0.05 mol.%, 0.1 mol.%, 1.0 mol.%, 1.5 mol.% and 2.0 mol.%） were prepared by conventional melt quenching technique. The structural and luminescence properties of the prepared Eu3＋ doped borophosphate glasses were studied and compared with reported results. The XRD pattern showed the amorphous nature of the prepared glasses. Whereas, the FTIR spectra revealed the vibrational modes in the prepared glasses. The bonding parameters（ β and ？） were calculated through the excitation spectra. Judd-Ofelt（J-O） intensity parameters were calculated from the emission spectra and were used to determine transition probability（A）, stimulated emission cross-section（σE P）, radiative lifetime（τR） and branching ratios（βexp） for the transition 5D0→7Fj（j=1, 2, 3 and 4） of Eu3＋ ions. Furthermore, the luminescence intensity ratio（R） of 5D0→7F2 to 5D0→7F1 transition was also calculated. Transition 5D0→7F2 had the highest value of stimulated emission cross-section and branching ratios and the results were comparable with the reported values. This indicated that the present glass is promising host material for Eu3＋ doped fiber amplifiers.

关键词： europium ions luminescence properties borophosphate glasses Judd^Ofelt analysis decay time rare earths

Identification of human microRNA-disease association via low-rank approximation-based link propagation and multiple kernel learning

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Frontiers of Computer science 2024年第2期18卷 217-229页

作者： Yizheng WANG Xin ZHANG Ying JU Qing LIU Quan ZOU Yazhou ZHANG Yijie DING Ying ZHANG institute of fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324000China Beidahuang Industry Group General Hospital Harbin 150088China School of Informatics Xiamen UniversityXiamen 361005China Department of Anesthesiology Hospital(T.C.M)Affiliated to Southwest Medical UniversityLuzhou 646000China Software Engineering College Zhengzhou University of Light IndustryZhengzhou 450002China

Numerous studies have demonstrated that human microRNAs(miRNAs)and diseases are associated and studies on the microRNA-disease association(MDA)have been *** developed a model using a low-rank approximation-based link propagation algorithm with Hilbert–Schmidt independence criterion-based multiple kernel learning(HSIC-MKL)to solve the problem of the large time commitment and cost of traditional biological experiments involving miRNAs and diseases,and improve the model *** constructed three kernels in miRNA and disease space and conducted kernel fusion using *** propagation uses matrix factorization and matrix approximation to effectively reduce computation and time *** results of the experiment show that the approach we proposed has a good effect,and,in some respects,exceeds what existing models can do.

关键词： human miRNA-disease association multiple kernel learning link propagation miRNA similarity disease similarity

C-Type Antiferromagnetic Structure of Topological Semimetal CaMnSb2

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Chinese Physics Letters 2024年第03期41卷 119-125页

作者：李博曾旭涛徐千惠杨帆项俊森钟恒扬邓司浩何伦华徐菊萍殷雯鲁兴业刘慧颖胜献雷金文涛 School of Physics Beihang University Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of Sciences Center for Advanced Quantum studies and Department of Physics Beijing Normal University Spallation Neutron Source science Center Songshan Lake Materials Laboratory

Determination of the magnetic structure and confirmation of the presence or absence of inversion （P） and time reversal （Τ） symmetry is imperative for correctly understanding the topological magnetic materials. He... 详细信息

关键词： Density functional theory

Effect of neutral polymeric bonding agent on tensile mechanical properties and damage evolution of NEPE propellant

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Defence Technology（防务技术） 2024年第2期32卷 357-367页

作者： M.Wubuliaisan Yanqing Wu Xiao Hou Kun Yang Hongzheng Duan Xinmei Yin State Key Laboratory of Explosion science and Technology Beijing Institute of TechnologyBeijing100081PR China The Fourth institute of China Aerospace science and Technology Corporation Xi'an710025PR China School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081PR China science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyHubei441003PR China

Introducing Neutral Polymeric bonding agents(NPBA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of new generations of the NEPE propellant with better mechanical properties. Therefore,understanding the effects of NPBA on the deformation and damage evolution of the NEPE propellant is fundamental to material design and applications. This paper studies the uniaxial tensile and stress relaxation responses of the NEPE propellant with different amounts of NPBA. The damage evolution in terms of interface debonding is further investigated using a cohesive-zone model(CZM). Experimental results show that the initial modulus and strength of the NEPE propellant increase with the increasing amount of NPBA while the elongation decreases. Meanwhile, the relaxation rate slows down and a higher long-term equilibrium modulus is reached. Experimental and numerical analyses indicate that interface debonding and crack propagation along filler-matrix interface are the dominant damage mechanism for the samples with a low amount of NPBA, while damage localization and crack advancement through the matrix are predominant for the ones with a high amount of NPBA. Finally, crosslinking density tests and simulation results also show that the effect of the bonding agent is interfacial rather than due to the overall crosslinking density change of the binder.

关键词： Solid propellant Bonding agent Mechanical properties Damage evolution Cohesive-zone model Interface debonding

Livelihood Vulnerability and Adaptation for Households Engaged in Forestry in Ecological Restoration Areas of the Chinese Loess Plateau

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Chinese Geographical science 2024年第5期34卷 849-868页

作者： YANG Qingqing CHEN Yang LI Xiaomin YANG Jie GAO Yanhui Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Geographical science and Tourism Shaanxi Normal UniversityXi’an 710119China School of Tourism and Research institute of Human Geography Xi’an International Studies UniversityXi’an 710128China

Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic ***,synergistic development may not be realized at the local *** areas undergoing ecological restoration,livelihood vulner-ability may be more pronounced due to the inflexibility,policy protection,and susceptibility to climate and market changes in forestry *** this issue has attracted academic interest,empirical studies are relatively *** study,centered on Jiaxian County,Shaanxi Province of China explored the households’livelihood vulnerability and coping strategies and group heterogeneity con-cerned with livelihood structures or forestry resources through field investigation,comprehensive index assessment,and nonparametric *** showed that:1)the percentage of households with high livelihood vulnerability indicator(LVI)(>0.491)reached 46.34%.2)Eight groups in livelihood structures formed by forestry,traditional agriculture,and non-farm activities were significantly different in LVI,land resources(LR),social networks(SN),livelihood strategies(LS),housing characteristics(HC),and socio-demo-graphic profile(SDP).3)The livelihood vulnerability of the groups with highly engaged/reliance on jujube(Ziziphus jujuba)forest demonstrated more prominent livelihood vulnerability due to the increased precipitation and cold market,where the low-engaged with reliance type were significantly more vulnerable in LVI,SDP,LR,and HC.4)The threshold of behavioral triggers widely varied,and farmers dependent on forestry livelihoods showed negative coping ***,the cutting behavior was strongly associated with lagged years and government subsidies,guidance,and high returns of ***,the findings can provide guidance on the dir-ection of livelihood vulnerability mitigation and adaptive government management in ecologically restored *** issue of farmers’livelihood sustainability in the context of ecologi

关键词： livelihood vulnerability forestry coping behaviors climate change market change Jiaxian County

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： Hai-Jun Li Ying-Quan Peng Wei Chao Yu-Feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China School of fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Impurity modes in two-dimensional strongly coupled complex plasma crystals

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Plasma science and Technology 2024年第8期26卷 1-7页

作者：吴诗杰徐韵乔冼顺宇何向磊杨肖易 School of Energy science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Complex plasma fluctuation processes have been extensively studied in many aspects,especially lattice waves in strongly coupled plasma crystals,which are of great significance for understanding fundamental physical phenomena.A challenge of experimental investigations in two-dimensional strongly coupled complex plasma crystals is to keep the main body and foreign particles of different masses on the same horizontal *** solve the problem,we have proposed a potential well formed by two negatively biased grids to bind the negatively charged particles in a two-dimensional(2D)plane,thus achieving a 2D plasma crystal in the microgravity *** study of such phenomena in complex plasma crystals under microgravity environment then becomes *** this paper,we focus on the continuum spectrum,including both phonon and optic branches of the impurity mode in a 2D system in microgravity *** results show the dispersion relation of the longitudinal and transverse impurity oscillation modes and their *** the macroscopic visibility of complex mesoscopic particle lattices,theoretical and experimental studies on this kind of complex plasma systems will help us further understand the physical nature of a wide range of condensed matters.

关键词： microgravity environment complex plasma lattice dispersion relation

通过镧掺杂调控提升电子缺陷型CoO的硝酸盐电还原制氨效率(英文)

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science China Materials 2024年

作者：何勋谢婷董凯南爵孙航姚永超范晓娅郑冬冬罗永嵩孙圣钧刘倩李露明储伟谢丽思孔清泉孙旭平 institute of fundamental and Frontier sciences University of Electronic Science and Technology of China College of Chemistry Chemical Engineering and Materials Science Shandong Normal University Department of science and Environmental studies Faculty of Liberal Arts and Social Science The Education University of Hong Kong institute for Advanced Study Chengdu University

电催化还原硝酸盐(NO3-)能有效转化NO3-为氨(NH3),实现废水中NO3-污染物的去除和NH3的生产.在本研究中,我们采用稀土元素镧掺杂的Co3O4纳米线阵列生长在碳布上(La-Co3O4/CC)作为高效的电催化剂,实现了NO3-向NH3的转化.La-Co3O4/CC展示...

电催化还原硝酸盐(NO3-)能有效转化NO3-为氨(NH3),实现废水中NO3-污染物的去除和NH3的生产.在本研究中,我们采用稀土元素镧掺杂的Co3O4纳米线阵列生长在碳布上(La-Co3O4/CC)作为高效的电催化剂,实现了NO3-向NH3的转化.La-Co3O4/CC展示了高的NH3法拉第效率(96.36%)和NH3产率(537.44μmol h-1cm-2),明显优于Co3O4(87.78%,279.4μmol h-1cm-2).理论计算表明,La掺杂促进了NO3-的吸附并优化了氢化过程,从而提高了Co3O4在NO3-转换和NH3选择性方面的电还原活性.此外,以La-Co3O4/CC组装的Zn-NO3-电池实现了9.86 mW cm-2的峰值功率密度.本项工作推动了基于Co3O4的电极在电催化领域的应用,并突显了稀土元素掺杂在NO3-还原反应中的有效性.

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