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The Choice of Mesh Size and Integration Points Number for the Electrostatically Controlled Membrane Antenna Structural-Electromagnetic Coupling Model

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Chinese Journal of Electronics 2024年第2期33卷 443-448页

作者： Yongzhen GU Qinggang ZHANG xiao yu Guixu LI Qingdao University of Science and Technology

It is of great significance for the improvement of the computational efficiency of the electrostatically controlled membrane antenna(ECMA) structural-electromagnetic coupling model through the choice of appropriate mesh size and integration points number. In this paper, the physical optics formulation is used to analyze the radiation pattern of the ECMA surface, and the finite element method is applied to the electrostatic-structural coupling analysis. An expression for the relation between the mesh size, the focal length of the parabolic antenna, and the wavelength is developed based on the discretization error analysis of the triangular mesh approximating the parabolic surface. Moreover, the integration points number in each triangular mesh is determined by the numerical evaluation of the physical optics integral. Numerical results show that the proposed method improves the computing efficiency by about 87% compared with the referenced method.

关键词： Couplings Surface waves Error analysis Computational modeling Physical optics Numerical models Finite element analysis

A Novel Gymnosperm Wood from the Lopingian(Late Permian)in Zhangzi,Shanxi,North China and Its Paleoecological and Paleogeographic Implications

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Journal of Earth Science 2024年第1期35卷 167-176页

作者： xiao Shi Jianxin yu yuewu Sun Zhen Xu Hui Li College of Earth Sciences Jilin UniversityChangchun 130061China International Center of Future Science Dinosaur Evolution Research CenterJilin UniversityChangchun 130012China State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China Research Center of Palaeontology and Stratigraphy Jilin UniversityChangchun 130026China Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China

The Permian-Triassic transition saw extreme climatic changes that severely impacted the terrestrial *** plants,particularly fossil woods,are sensitive to climatic changes,and they,therefore,are unique materials revealing extreme environmental and climatic changes on land at that *** conifer woods were discovered in the Lopingian(Late Permian)strata of the Sunjiagou Formation in Shanxi Province,North *** newly finding permineralized woods record the unique landscape of Lopingian North *** represent a new conifer genus and species:Shanxiopitys zhangziensis *** *** of growth pattern and anatomical characteristics of the fossil woods indicate these trees grew under optimal growing conditions,and without seasonal growth ***,climate signals from leaf fossils,vertebrate fossils and sedimentary evidences indicate a strongly seasonal climate in North China during the ***,it is speculated that these trees likely lived in the gallery forests,which were distributed along the paleo-rivers within a seasonal landscape in the central North China block during the Lopingian.

关键词： Shanxiopitys zhangziensis gen.et sp.nov. wood ecology geography gallery forest Lopingian North China

Metagenomic insights into microorganisms and antibiotic resistance genes of waste antibiotic fermentation residues along production,storage and treatment processes

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Journal of Environmental Sciences 2024年第2期136卷 45-55页

作者： Ziming Han xiao Luan Haodi Feng Yanqin Deng Min Yang yu Zhang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery Beijing 100085China Wuhan Agricultural Inspection Center Wuhan 430016China University of Chinese Academy of Sciences Beijing 100049China

Antibiotic fermentation residue(AFR)is nutrient-rich solid waste generated from fermentative antibiotic production *** is demonstrated that AFR contains high-concentration of remaining antibiotics,and thus may promote antibiotic resistance development in receiving environment or feeding farmed ***,the dominate microorganisms and antibiotic resistance genes(ARGs)in AFRs have not been adequately explored,hampering understanding on the potential antibiotic resistance risk development caused by ***,seven kinds of representative AFRs along their production,storage,and treatment processes were collected,and multiple methods including amplicon sequencing,metagenomic sequencing,and bioinformatic approaches were adopted to explore the biological characteristics of *** expected,antibiotic fermentation producer was found as the predominant species in raw AFRs,which were collected at the outlet of fermentation ***,except for producer species,more environment-derived species persisted in stored AFRs,which were temporarily stored at a semi-open *** genus,classified as Firmicutes phylum and Bacilli class,became predominant bacterial taxa in stored AFRs,which might attribute to its tolerance to high concentration of *** from metagenomic sequencing together with assembly and binning approaches showed that these newly-colonizing species(e.g.,Lactobacillus genus)tended to carry ARGs conferring resistance to the remaining ***,after thermal treatment,remaining antibiotic could be efficiently removed from AFRs,and microorganisms together with DNA could be strongly *** sum,the main risk from the AFRs was the remaining antibiotic,while environment-derived bacteria which tolerate extreme environment,survived in ARFs with high content antibiotics,and may carry ***,hydrothermal or other harmless treatment technologies are recommended to remove antibiotic content and inactivate bacteria befor

关键词： Pharmaceutical manufacturing Antibiotic mycelia residue Antibiotic resistance bacteria Thermal treatment Solid waste

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying Qin Kai-Fan Ji Hui Liu xiao-Guang yu yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2.10 April to 2.11 February was used as the training set,1332.pairs from 2.11 March were used as the validation set and 1034 pairs from 2.11 April were used as the test *** data preprocessing,we randomly cropped 12.×12. sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512.512.sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Core shift limitation in investment casting process of hollow turbine blade

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Chinese Journal of Aeronautics 2024年第8期37卷 513-526页

作者： Kang CUI Lin JING Ruisong JIANG Longnv yu xiao GAO Automation and Software Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologySchool of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Mechanical Engineering Sichuan UniversityChengdu 610065China

The deviation in wall thickness caused by core shift during the investment casting process significantly impacts the strength and service life of hollow turbine *** address this issue,a core shift limitation method is developed in this ***,a shift model is established based on computational fluid dynamics and motion simulation to predict the movement of the ceramic core in investment casting ***,utilizing this model,an optimization method for fixturing layout inside the refractory ceramic shell is devised for the ceramic *** casting experiment demonstrates that by utilizing the optimized fixture layout,not only can core shift during the investment casting pouring process be effectively controlled,but also the maximum wall thickness error of the blade can be reduced by 42.02..In addition,the core shift prediction is also validated,with a prediction error of less than 2..9%.

关键词： Hollow turbine blade Wall thickness Ceramic core Shift prediction Fixturing layout optimization

Neural Dynamics for Cooperative Motion Control of Omnidirectional Mobile Manipulators in the Presence of Noises: A Distributed Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1605-1620页

作者： yufeng Lian Xingtian xiao Jiliang Zhang Long Jin Junzhi yu Zhongbo Sun the Department of Control Engineering Changchun University of TechnologyChangchun 130012China IEEE the College of Information Science and Engineering Northeastern UniversityShenyang 110819 the National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China the School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China the State Key Laboratory for Turbulence and Complex Systems Department of Advanced Manufacturing and RoboticsCollege of EngineeringPeking UniversityBeijing 100871China

This paper presents a distributed scheme with limited communications, aiming to achieve cooperative motion control for multiple omnidirectional mobile manipulators(MOMMs).The proposed scheme extends the existing single-agent motion control to cater to scenarios involving the cooperative operation of MOMMs. Specifically, squeeze-free cooperative load transportation is achieved for the end-effectors of MOMMs by incorporating cooperative repetitive motion planning(CRMP), while guiding each individual to desired poses. Then, the distributed scheme is formulated as a time-varying quadratic programming(QP) and solved online utilizing a noise-tolerant zeroing neural network(NTZNN). Theoretical analysis shows that the NTZNN model converges globally to the optimal solution of QP in the presence of noise. Finally, the effectiveness of the control design is demonstrated by numerical simulations and physical platform experiments.

关键词： Cooperative motion control noise-tolerant zeroing neural network(NTZNN) omnidirectional mobile manipulator(OMM) repetitive motion planning

Recent Developments of Photodeformable Polymers:From Materials to Applications

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Research 2024年第2期2023卷 729-752页

作者： Shuting Kong Hailan Wang Eethamukkala Ubba yuxin xiao Tao yu Wei Huang Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)Northwestern Polytechnical University127 West Youyi RoadXian 710072China OMC Research Laboratory.Department of Chemistry School of Advanced SciencesVITVelloreTamilnaduIndia Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)30 South Puzhu RoadNanjing 211816China State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing 210023China

Photodeformable polymer materials have a far influence in the fields of flexibility and *** stimulation energy is converted into mechanical energy through molecular *** kinds of photodeformable polymer materials,liquid crystalline polymer(LCP)photodeformable materials have been a hot topic in recent *** such as azobenzene,a-cyanostilbene,and 9,10-dithiopheneanthracene have been widely used in LCP,which are helpful for designing functional molecules to increase the penetration depth of light to change physical *** to the various applications of photodeformable polymer materials,there are many excellent reports in intelligent *** this review,we have systematized LCP containing azobenzene into 3 categories depending on the degree of crosslinking liquid crystalline elastomers,liquid crystalline networks,and linear *** structural,typical polymer materials and their applications are *** issues faced and future directions to be developed for photodeformable polymer materials are also summarized.

关键词： properties. field. crystalline

Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao Hou Zhiqiang yu Shefa Chen Lei Liu Yilin xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2.,similar to those of titanites in eclogite(14.2.16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry

Atomistic mechanism of high ionic conductivity in lithium ytterbium-based halide solid electrolytes:A first-principles study

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Journal of Rare Earths 2024年第1期42卷 155-162,I0006页

作者： Limin Wang Wei xiao Lu Sun Rong Yang Jinqiu yu Ligen Wang State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co.Ltd.Beijing100088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute Co. Ltd.Beijing101407China Rare Earth Functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an071700China

As the next generation of commercial automotive power batteries begins replacing liquid lithium batteries,many look towards all-solid-state batteries to pioneer the ***-so lid-state batteries have attracted the attention of countless researchers around the world because of their high safety and high energy *** recent times,halide solid-state electrolytes have become a research hotspot within solid-state electrolytes because of their potentially superior *** this paper,in the framework of DFT,we investigated the atomic mechanisms of improving the ionic conductivity and stability of Li_(3)YbCl_(6).Our calculations show that both trigonal and orthorhombic Li_(3)YbCl_(6) exhibit wide electrochemical windows and metastable properties(100 meV/atom>Ehull>0 meV/atom).However,the orthorhombic Li_(3)YbCl_(6) can be stabilized at high temperatures by taking the vibrational entropy into account,which is supported by the experimental ***,it is expected that because of the Yb/Li synergistic interactions that,due to their strong mutual coulomb repulsion,influence the Li^(+)transport behavior,the orthorhombic Li_(3)YbCl_(6) might have superior ionic conductivities with appropriate Li+migration paths determined by the Yb^(3+) ***,higher ionic conductivities can be obtained by regulating the random distribution of Li^(+) *** Li^(+)-deficiency can also largely increase the ionic conductivity by invoking *** study helps gain a deeper understanding of the laws that govern ionic conductivities and stabilities and provides a certain theoretical reference for the experimental development and design of halide solid-state electrolytes.

关键词： Halide solid-state electrolytes Phase stability Ionic conductivity First-principles calculations Rare earths