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Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu SUN yujian cheng School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

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W-Band High-Efficiency Waveguide Slot Array Antenna with Low Sidelobe Levels Based on Silicon Micromachining Technology

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Chinese Journal of Electronics 2022年第4期31卷 665-673页

作者： YAO Shisen cheng yujian BAI Hang FAN Yong University of Electronic Science and Technology of China

A high-efficiency waveguide slot array antenna with low sidelobe level(SLL) is investigated for W-band applications. The silicon micromachining technology is utilized to realize multilayer antenna architecture by three key steps of selective etching, gold plating and Au-Au bonding. The radiating slot based on this technique becomes thick with a minimum thickness of 0.2 mm and accompanies with the decrease of slot's radiation ability. To overcome this weakness, a stepped radiation cavity is loaded on the slot. The characteristic of cavityloaded slot is investigated to synthesize the low-SLL array antenna. The unequal hybrid corporate feeding network is constructed to achieve sidelobe suppression in the E-plane. A pair of 16 × 8 low-SLL and high-effciency slot arrays is fashioned and confirmed experimentally. The bandwidth with the radiation effciency higher than 80% is92.3–96.3 GHz. The SLLs in both E-and H-planes are below-19 d B.

关键词： Antenna accessories slot antenna arrays radiation cavity low sidelobe level micromachining W-band high efficiency waveguide slot array antenna silicon Surface treatment (semiconductor technology) Antenna arrays Fabrication of MEMS and NEMS devices high effciency slot arrays low-SLL array antenna antenna radiation patterns W-band applications sidelobe suppression high-effciency slot arrays etching radiating slot Au-Au bonding radiation effciency silicon micromachining technology planar antenna arrays antenna feeds gold multilayer antenna architecture

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Design of a multimode beamforming network based on the scattering matrix analysis

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Science in China(Series F) 2009年第7期52卷 1258-1265页

作者： cheng yujian HONG Wei WU Ke State Key Laboratory of Millimeter Waves School of information Science and Engineering Southeast University Nanjing 210096China Poly-Grames Research Center Department of Electrical Engineering Ecole Polytechnique (University of Montreal) Montreal QCH3C 3A7 Canada

The investigation of the multimode beamforming network （BFN） has been developed from its scattering matrix （S-matrix） analysis. A substrate integrated waveguide （SIW） BFN is designed and fabricated on a single Rogers 5880 substrate. This device is not only marked by features of conventional BFN, such as Butler matrix, but also has additional benefits, e.g. more compact configuration and higher radiation efficiency. Measured and simulated results based on the proposed structure are in a good agreement, which indicates that this novel type of BFN has good characteristics and presents an excellent candidate in the development of intelligent microwave and millimeter-wave multibeam antenna systems.

关键词： multimode beamforming network (BFN) multibeam antenna substrate integrated waveguide (SIW)

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Dynamic modeling of wave driven unmanned surface vehicle in longitudinal profile based on D-H approach

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Journal of Central South University 2015年第12期22卷 4578-4584页

作者：田宝强俞建成张艾群 State Key Laboratory of Robotics (Chinese Academy of Sciences) University of Chinese Academy of Sciences

Wave driven unmanned surface vehicle(WUSV) is a new concept ocean robot drived by wave energy and solar energy,and it is very suitable for the vast ocean observations with incomparable *** dynamic modeling is very important because it is the theoretical foundation for further study in the WUSV motion control and efficiency *** this work,the multibody system of WUSV was described based on D-H ***,the driving principle was analyzed and the dynamic model of WUSV in longitudinal profile is established by Lagrangian ***,the motion simulation of WUSV and comparative analysis are completed by setting different inputs of sea *** results show that the WUSV dynamic model can correctly reflect the WUSV longitudinal motion process,and the results are consistent with the wave theory.

关键词： wave driven unmanned surface vehicle D-H approach Lagrangian mechanics dynamic analysis

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A new neural-network-based method for structural damage identification in single-layer reticulated shells

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 104-121页

作者： Jindong ZHANG Xiaonong GUO Shaohan ZONG yujian ZHANG College of Civil Engineering Tongji UniversityShanghai 200092China China Construction Eighth Engineering Division Co. Ltd.Shanghai 200135China

Single-layer reticulated shells(SLRSs)find widespread application in the roofs of crucial public structures,such as gymnasiums and exhibition *** this paper,a new neural-network-based method for structural damage identification in SLRSs is ***,a damage vector index,NDL,that is related only to the damage localization,is proposed for SLRSs,and a damage data set is constructed from NDL *** the basis of visualization of the NDL damage data set,the structural damaged region locations are identified using convolutional neural networks(CNNs).By cross-dividing the damaged region locations and using parallel CNNs for each regional location,the damaged region locations can be quickly and efficiently identified and the undamaged region locations can be ***,a damage vector index,DS,that is related to the damage location and damage degree,is proposed for *** on the damaged region identified previously,a fully connected neural network(FCNN)is constructed to identify the location and damage degree of *** effectiveness and reliability of the proposed method are verified by considering a numerical case of a spherical *** calculation results showed that the proposed method can quickly eliminate candidate locations of potential damaged region locations and precisely determine the location and damage degree of members.

关键词： single-layer reticulated shell damage identification neural network convolutional neural network cross-partitioning method

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12.6μm-Thick Asymmetric Composite Electrolyte with Superior Interfacial Stability for Solid-State Lithium-Metal Batteries

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Nano-Micro Letters 2024年第9期16卷 397-409页

作者： Zheng Zhang Jingren Gou Kaixuan Cui Xin Zhang yujian Yao Suqing Wang Haihui Wang Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510000People’s Republic of China

Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety ***,there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes,and to minimize the electrolyte thickness to achieve highenergy-density of ***,we develop an ultrathin(12.6μm)asymmetric composite solid-state electrolyte with ultralight areal density(1.69 mg cm^(−2))for *** electrolyte combining a garnet(LLZO)layer and a metal organic framework(MOF)layer,which are fabricated on both sides of the polyethylene(PE)separator separately by tape *** PE separator endows the electrolyte with flexibility and excellent mechanical *** LLZO layer on the cathode side ensures high chemical stability at high *** MOF layer on the anode side achieves a stable electric field and uniform Li flux,thus promoting uniform Li^(+)*** to the well-designed structure,the Li symmetric battery exhibits an ultralong cycle life(5000 h),and high-voltage SSLMBs achieve stable cycle *** assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg^(−1)/773.1 Wh L^(−1).This simple operation allows for large-scale preparation,and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs.

关键词： Solid-state lithium metal batteries Composite solid-state electrolyte Ultrathin asymmetric structure Pouch cells

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Migration mechanism and risk assessment of perand polyfluoroalkyl substances in the Ya'Er Lake oxidation pond area,China

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Journal of Environmental Sciences 2024年第2期136卷 301-312页

作者： Chang Li Huifang Zhong Jing Wu Lingyi Meng Yingjun Wang Chunyang Liao Yawei Wang yujian He University of Chinese Academy of Sciences Beijing 100049China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China China National Environmental Monitoring Centre Beijing 100012China Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

The migration mechanisms,sources,and environmental risks of 29 legacy and emerging perfluorinated and polyfluoroalkyl species present in an oxidation pond(Ya'Er Lake)were investigated for treating sewage based on the analysis of their occurrence and *** concentration of per-and polyfluoroalkyl substances(PFAS)in pond area was between0.30 and 63.2 ng/g dw(dry weight),with the overall average concentration of 8.00 ng/g ***,the PFAS concentrations in the surface sediments near the sewage outlet in Pond-1(50.2 ng/g dw)and Pond-5(average 15.1 ng/g dw)were 1–2 orders of magnitude higher than those in other *** general,the legacy PFAS,i.e.,perfluorooctane sulfonic acid was considered to be the major pollutant in the polluted area,on average,accounting for 73.0%of the total concentration of PFAS *** evaluating the regional distribution of different PFAS homologs,the short-chain PFAS pollutants with lower K_(ow)were found to migrate farther in both horizontal and vertical *** sewage outlets in Pond-1 and Pond-5are the main pollution sources in polluted area and the emerging PFAS pollutants in Pond-5have replaced the legacy PFAS pollutants as the main *** on positive matrix factorization analysis,three main industrial sources of PFAS pollutants in the study area were identified:protective coating,fire-fighting,and food packaging ***,the environmental risk assessment results showed that most study areas exhibited medium environmental risk(0.01≤Risk quotient(RQ)<1),indicating that the ecological environment risks in this area need further attention.

关键词： Perfluoroalkyl substances Distribution Migration mechanism Risk assessment

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Maternal resveratrol improves the intestinal health and weight gain of suckling piglets during high summer temperatures: The involvement of exosome-derived microRNAs and immunoglobin in colostrum

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Animal Nutrition 2024年第2期17卷 36-48页

作者： Changming Hong yujian Huang Guan Yang Xiaolu Wen Li Wang Xuefen Yang Kaiguo Gao Zongyong Jiang Hao Xiao State Key Laboratory of Swine and Poultry Breeding Industry Institute of Animal ScienceGuangdong Academy of Agricultural Sciences Key Laboratory of Animal Nutrition and Feed Science in South China Ministry of Agriculture and Rural AffairsGuangdong Public Laboratory of Animal Breeding and Nutrition Guangdong Provincial Key Laboratory of Animal Nutrition Control Institute of Subtropical Animal Nutrition and FeedCollege of Animal ScienceSouth China Agricultural University Department of Infectious Diseases and Public Health Jockey Club College of Veterinary Medicine and Life SciencesCity University of Hong Kong

Previous studies have shown that maternal resveratrol improved growth performance and altered the microbial composition of suckling piglets under hot summer conditions. However, it remains unclear how maternal resveratrol improves growth performance of suckling piglets during high summer temperatures. A total of 20 sows(Landrace × Large White; three parity) were randomly assigned to 2 groups(with or without 300 mg/kg resveratrol) from d 75 of gestation to d 21 of lactation during high ambient temperatures(from 27 to 30℃). The results showed that maternal resveratrol supplementation increased total daily weight gain of piglets under hot summer conditions, which is consistent with previous studies. Furthermore, we found that maternal resveratrol improved the intestinal morphology and intestinal epithelial proliferation in suckling piglets. Dietary resveratrol supplementation affected the characteristics of exosome-derived microRNAs(miRNAs) in sow colostrum, as well as the genes targeted by differentially produced miRNAs. MiRNAs are concentrated in the tight junction pathway. As a result, the expression of intestinal tight junction proteins was increased in suckling piglets(P < 0.05).Notably, maternal resveratrol increased the intestinal secretory immunoglobulin A(sIgA) levels of suckling piglets via colostrum immunoglobin(P < 0.05), which could increase the abundance of beneficial microbiota to further increase the concentration of short chain fatty acids(SCFA) in suckling piglets' intestine(P < 0.05). Finally, our correlation analysis further demonstrated the positive associations between significantly differential intestinal microbiota, intestinal sIgA production and SCFA concentrations,as well as the positive relation between total daily weight gain and intestinal health of suckling *** together, our findings suggested that maternal resveratrol could promote intestinal health to improve piglet growth during high summer temperatures, which might be associa

关键词： Colostrum Exosome Immunoglobulin Intestinal health Resveratrol

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Accurate models and nutritional strategies for specific oxidative stress factors: Does the dose matter in swine production?

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Journal of Animal Science and Biotechnology 2024年第2期15卷 519-534页

作者： Changming Hong yujian Huang Shuting Cao Li Wang Xuefen Yang Shenglan Hu Kaiguo Gao Zongyong Jiang Hao Xiao State Key Laboratory of Swine and Poultry Breeding Industry Ministry of Agriculture Key Laboratory of Animal Nutrition and Feed Science in South ChinaGuangdong Public Laboratory of Animal Breeding and NutritionGuangdong Provincial Key Laboratory of Animal Breeding and NutritionMaoming BranchGuangdong Laboratory for Lingnan Modern AgricultureGuangzhouChina Institute of Animal Science Guangdong Academy of Agricultural Sciences1 Dafeng 1st StreetGuangzhou 510640China

Oxidative stress has been associated with a number of physiological problems in swine,including reduced production ***,although there has been increased research into regulatory mechanisms and antioxidant strategies in relation to oxidative stress-induced pig production,it remains so far largely unsuccessful to develop accurate models and nutritional strategies for specific oxidative stress ***,we discuss the dose and dose intensity of the causes of oxidative stress involving physiological,environmental and dietary factors,recent research models and the antioxidant strategies to provide theoretical guidance for future oxidative stress research in swine.

关键词： Accurate models Dose Nutritional strategies Oxidative stress Swine

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认知相对论——通向强人工智能之路

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电子与信息学报 2024年第2期46卷 408-427页

作者：李玉鑑桂林电子科技大学人工智能学院桂林541004

人工智能(AI)的发展如火如荼,大有超越人类之势,以致很多人认为奇点就要来临,强人工智能即将实现。这是一种对强人工智能的误解,因为强人工智能的核心并不在于其功能是否强大,而在于它是否具有意识。该文首先解释了强人工智能的内涵,讨... 详细信息

人工智能(AI)的发展如火如荼,大有超越人类之势,以致很多人认为奇点就要来临,强人工智能即将实现。这是一种对强人工智能的误解,因为强人工智能的核心并不在于其功能是否强大,而在于它是否具有意识。该文首先解释了强人工智能的内涵,讨论了与之相关的意识问题;然后,阐述了旨在揭开意识奥秘的认知相对论思想,包括:世界的相对性原理和符号的相对性原理,以及世界、语言和心灵的关系。接着,提出了另一条新原理,即意识的等效原理,用以说明意识从物质产生所需要的物理条件,解决主观体验或现象意识的困难问题,推导意识能力受限于感觉能力且以感觉容量为上界的认知基本定理,并分析意识在哪里和自我是什么的可能性。最后,在认知相对论的框架下,给出了研究意识问题的新纲领和实现机器意识的新思路,并展望了强人工智能的未来。

关键词：人工智能强人工智能意识机器意识认知相对论

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