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Chinese Journal of Aeronautics 2024年第9期37卷 417-432页

作者： Heng jing Zixuan ZHENG Deja che.Jianping YUAN National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi'an 710072China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China

Inertial characteristics of non-cooperative targets are crucial for space capture and sub-sequent on-orbit *** methods for identifying inertial parameters involve proximity operations,which are associated with the risk of collision with non-cooperative *** paper introduces a long-range,contactless method for identifying the inertial parameters of a non-cooperative target during the pre-capture ***,electrostatic interaction is used as an external excitation to alter the target's motion.A force estimation algorithm that uses measure-ments from visual and potential sensors is proposed to estimate the electrostatic interaction and eliminate the need for force ***,a recursive estimation-identification framework is presented to concurrently estimate the coupled motion state,weak electrostatic interaction,and inertial parameters of the *** simulation results show that the proposed method extends the identification distance to 170 times that of the previous method while maintaining high identifica-tion precision forall parameters.

关键词： Non-cooperative target Inertial parameters identification Electrostatic interaction Force estimation Dynamical coupling

Parametric“non-nested”discriminants for multiplicities of univariate polynomials

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Science China Mathematics 2024年第8期67卷 1911-1932页

作者： Hoon hong jing Yang Department of Mathematics North Carolina State UniversityRaleighNC 27695USA SMS-HCIC-School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006China

We consider the problem of complex root classification,i.e.,finding the conditions on the coefficients of a univariate polynomial for all possible multiplicity structures on its complex *** is well known that such conditions can be written as conjunctions of several polynomial equalities and one inequality in the *** polynomials in the coefficients are called discriminants for *** is also known that discriminants can be obtained using repeated parametric greatest common *** resulting discriminants are usually nested determinants,i.e.,determinants of matrices whose entries are determinants,and so *** this paper,we give a new type of discriminant that is not based on repeated greatest common *** new discriminants are simpler in the sense that they are non-nested determinants and have smaller maximum degrees.

关键词： parametric polynomial complex roots discriminant multiplicity resultant

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Chiral mesostructured hematite with temperature-independent magnetism due to spin confinement

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Nano Research 2024年第3期17卷 2019-2024页

作者： Baiwen Zhang jing Ai Yingying Duan Te Bai Lu Han Shunai che School of Physics Science and Engineering Tongji UniversityShanghai 200092China School of che.istry and che.ical Engineering Tongji UniversityShanghai 200092China Wuxi Vocational College of Science and Technology Wuxi 214028China School of che.istry and che.ical Engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Hematite(α-Fe_(2)O_(3))is known to undergo conversion from weak ferromagnetic to antiferromagnetic as the temperature decreases below the Morin temperature(TM=250 K)due to spin moment rotation occurring during the Morin transition(MT).Herein,we endowed hematite with mesostructured chirality to maintain weak ferromagnetism without *** mesostructured hematite(CMH)nanoparticles were prepared by a hydrothermal method with glutamic acid(Glu)as the symmetry-breaking *** triangular bipyramidal CMH nanoparticles were composed of helically cleaved nanoflakes with twisted crystal ***-cooled(FC)magnetization measurements showed that the magnetic moments of CMH were stabilized without MT within the temperature range of 10–300 *** loop measurements confirmed the weak ferromagnetism of *** enhanced Dzyaloshinskii–Moriya interaction(DMI)was speculated to be responsible for the temperature-independent weak ferromagnetism,in which the spin configuration would be confined with canted antiferromagnetic coupling due to the mesostructured chirality of CMH.

关键词： hematite chiral mesostructure Dzyaloshinskii–Moriya interaction weak ferromagnetism antiferromagnetic material temperature-independent magnetism

Determination of multilevel chirality in nickel molybdate films by electron crystallography

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Nano Research 2024年第9期17卷 8571-8577页

作者： jing Ai Yu Wang Liyuan Li Jianqiang Wang Te Bai Shunai che.Lu Han Sinopec(Shanghai)Research Institute of Petroche.ical Technology Co. Ltd.Shanghai 201208China School of che.ical Science and Engineering Tongji UniversityShanghai 200092China School of che.istry and che.ical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Chiral inorganic materials have attracted great attention owning to their unique physical and che.ical properties attributed to the symmetry-breaking of their *** inorganic materials can be endowed with chiral geometric configurations from achiral space group crystals through lattice twisting,screw dislocations or hierarchical self-assembled spiral morphologies,showing various characteristic chiral ***,the multilevel chirality in chiral nickel molybdate films(CNMFs)remains to be elaborately *** this paper,we report three hierarchical levels of chirality in CNMFs,spanning from the atomic to the micron scale,including primary helically coiled nanoflakes with twisted atomic crystal lattices,secondary helical stacking of layered nanoflakes,and tertiary asymmetric morphology between adjacent *** findings may enrich the chiral self-assembly structural types and provide valuable insights for the comprehensive analysis path of hierarchical chiral crystals.

关键词： chiral inorganic material nickel molybdate structural analysis transmission electron microscopy electron crystallography

Ohmic-contact ballistic 2D In Se transistors:promising candidates for more Moore electronics

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Science China(Information Sciences) 2024年第3期67卷 311-312页

作者： hong LI Qiuhui LI jing LU College of Mechanical and Material Engineering North China University of Technology State Key Laboratory for Mesoscopic Physics and Department of Physics Collaborative Innovation Center of Quantum Matter Beijing Key Laboratory for Magnetoelectric Materials and Devices Peking University Yangtze Delta Institute of Optoelectronics Key Laboratory for the Physics and che.istry of Nanodevices Peking University

The scaling of silicon-based metal-oxide-semiconductor fieldeffect transistors(MOSFETs) approache. its physical limits at a gate length(LG) of 12 nm and supply voltage(VDD) of 0.6 V according to the International Road...

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Constrained clustering with weak label prior

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Frontiers of Computer Science 2024年第3期18卷 117-132页

作者： jing ZHANG Ruidong FAN hong TAO Jiache.g JIANG che.ping HOU College of Sciences National University of Defense TechnologyChangsha 410073China

Clustering is widely exploited in data *** has been proved that embedding weak label prior into clustering is effective to promote its *** researche. mainly focus on only one type of ***,in many real scenarios,two kinds of weak label prior information,e.g.,pairwise constraints and cluster ratio,are easily obtained or already *** to incorporate them to improve clustering performance is important but rarely *** propose a novel constrained Clustering with Weak Label Prior method(CWLP),which is an integrated *** the unified spectral clustering model,the pairwise constraints are employed as a regularizer in spectral embedding and label proportion is added as a constraint in spectral *** approximate a variant of the embedding matrix more precisely,we replace a cluster indicator matrix with its scaled *** of fixing an initial similarity matrix,we propose a new similarity matrix that is more suitable for deriving clustering *** for the theoretical convergence and computational complexity analyses,we validate the effectiveness of CWLP through several benchmark datasets,together with its ability to discriminate suspected breast cancer patients from healthy *** experimental evaluation illustrates the superiority of our proposed approach.

关键词： clustering weak label prior cluster ratio pairwise constraints

Phytogenic feed additives as natural antibiotic alternatives in animal health and production: A review of the literature of the last decade

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Animal Nutrition 2024年第2期17卷 244-264页

作者： jing Wang Lufang Deng Meixia che. Yuyan che.Lu Li Longlong Zhu Guoshun che. Tao Feng Institute of Animal Husbandry and Veterinary Medicine Beijing Academy of Agriculture and Forestry Sciences Sino-US Joint Laboratory of Animal Science Beijing Academy of Agriculture and Forestry Sciences Feed Branch of Beijing Sanyuan Breeding Technology Co. Ltd. College of Animal Science and Technology Gansu Agricultural University College of Life Science and Food Engineering Hebei University of Engineering College of Animal Science and Technology Henan University of Science and Technology

The use of antibiotics in animal production raises great public safety concerns; therefore, there is an urgent need for the development of substitutes for antibiotics. In recent decades, plant-derived feed additives have been widely investigated as antibiotic alternatives for use in animal health and production because they exert multiple biological functions and are less likely to induce resistance *** review summarizes the research history and classification of phytogenic feed additives and their main functions, potential modes of action, influencing factors, and potential negative effects. Further, we highlight the challenges in developing sustainable, safe, and affordable plant-derived antibiotic alternatives for use in livestock production.

关键词： Phytogenic feed additives Antibiotic alternatives Livestock animals Health Production

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu hong-wu Tang Sai-yu Yuan jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

A Cauchy integral formula for(p,q)-monogenic functions withα-weight

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 545-553页

作者： GAO Long DU Xiao-jing LIU Yue XIE Yong-hong School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are ***,the Cauchy-Pompeiu formula is ***,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic function... 详细信息

关键词： (p q)-monogenic functions with-weight Cauchy-Pompeiu formula Cauchy integral formula Cauchy integral theorem

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Differential Game Model of Resource Extraction with Continuous and Dynamic Updating

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Journal of the Operations Research Society of China 2024年第1期12卷 51-75页

作者： Ovanes Petrosian Tihomirov Denis Jiang-jing Zhou hong-Wei Gao School of Mathematics Harbin Institute of TechnologyHarbin150001HeilongjiangChina School of Automation Qingdao UniversityQingdao266071ShandongChina Faculty of Applied Mathematics and Control Processes Saint-Petersburg State UniversitySaint PetersburgRussia National Research University"High School of Economics" Saint-PetersburgRussia School of Mathematics and Statistics Qingdao UniversityQingdao266071ShandongChina

This paper is devoted to a new class of differential games with continuous and dynamic *** direct application of resource extraction in a case of dynamic and continuous updating is *** is proved that the optimal control(cooperative strategies)and feedback Nash equilibrium strategies uniformly converge to the corresponding strategies in the game model with continuous updating as the number of updating instants converges to *** results are presented for an optimal trajectory(cooperative trajectory),equilibrium trajectory and corresponding payoffs.

关键词： Differential games Dynamic updating Continuous updating Optimal control Feedback Nash equilibrium