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Wireless Engineering and Technology 2011年第4期2卷 257-261页

作者： Chia-Song Wu Tah-Yeong Lin chien-huang chang Hsien-Ming Wu 不详

The objective of this paper is to investigate a ultra-wideband (UWB) low noise amplifier (LNA) by utilizing a two-stage cascade circuit schematic associated with inductive-series peaking technique, which can improve the bandwidth in the 3-10 GHz microwave monolithic integrated circuit (MMIC). The proposed UWB LNA amplifier was implemented with both co-planer waveguide (CPW) layout and 0.15-μm GaAs D-mode pHEMT technology. Based on those technologies, this proposed UWB LNA with a chip size of 1.5 mm x 1.4 mm, obtained a flatness gain 3-dB bandwidth of 4 - 8 GHz, the constant gain of 4 dB, noise figure lower than 5 dB, and the return loss better than –8.5 dB. Based on our experimental results, the low noise amplifier using the inductive-series peaking technique can obtain a wider bandwidth, low power consumption and high flatness of gain in the 3 - 10 GHz. Finally, the overall LNA characterization exhibits ultra-wide bandwidth and low noise characterization, which illustrates that the proposed UWB LNA has a compact size and favorable RF characteristics. This UWB LNA circuit demonstrated the high RF characterization and could provide for the low noise micro-wave circuit applications.

关键词： Ultra-Wideband (UWB) Low Noise Amplifier (LNA) CPW pHEMT MMIC

Hierarchical Task Planning for Power Line Flow Regulation

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 29-40页

作者： Chenxi Wang Youtian Du Yanhao huang Yuanlin chang Zihao Guo the Ministry of Education Key Lab for Intelligent Networks and Network Security Xi'an Jiaotong UniversityXi'an 713599China the State Key Laboratory of Power Grid Safety and Energy Conservation China Electric Power Research InstituteBeijing 100192China

The complexity and uncertainty in power systems cause great challenges to controlling power *** a popular data-driven technique,deep reinforcement learning(DRL)attracts attention in the control of power ***,DRL has some inherent drawbacks in terms of data efficiency and *** paper presents a novel hierarchical task planning(HTP)approach,bridging planning and DRL,to the task of power line flow ***,we introduce a threelevel task hierarchy to model the task and model the sequence of task units on each level as a task planning-Markov decision processes(TP-MDPs).Second,we model the task as a sequential decision-making problem and introduce a higher planner and a lower planner in HTP to handle different levels of task *** addition,we introduce a two-layer knowledge graph that can update dynamically during the planning procedure to assist *** results conducted on the IEEE 118-bus and IEEE 300-bus systems demonstrate our HTP approach outperforms proximal policy optimization,a state-of-the-art deep reinforcement learning(DRL)approach,improving efficiency by 26.16%and 6.86%on both systems.

关键词： Knowledge graph power line flow regulation reinforcement learning task planning

Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection

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Earth and Planetary Physics 2024年第3期8卷 472-478页

作者： Cong chang QuanMing Lu San Lu Kai huang RongSheng Wang Deep Space Exploration Laboratory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology CAS Key Laboratory of Geospace EnvironmentHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic *** electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow *** the inner EDR,the speed of the electron outflow increases when the electrons move away from the X *** the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer *** the boundary of the outer EDR,the magnetic field piles up and forms a depolarization *** the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been *** the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane *** the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron *** electric field forces and electron gradient forces tend to drag the electron *** acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion *** these two terms are important,their effects on ions are almost *** Hall electric field force does positive work on ions and is not *** ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front.

关键词： collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation

Dual-filler reinforced PVDF-HFP based polymer electrolyte enabling high-safety design of lithium metal batteries

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Nano Research 2024年第6期17卷 5251-5260页

作者： chang Fang Kangsheng huang Jing Zhao Shiqi Tian Hui Dou Xiaogang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

Despite the high energy density of lithium metal batteries(LMBs),their application in rechargeable batteries is still hampered due to insufficient ***,we present a novel flame-retardant solid-state electrolyte based on polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)with nano SiO_(2)aerogel as an inert filler but Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)as an auxiliary component to enhance the ion *** introduction of SiO_(2)aerogels imparts the polymer electrolyte with exceptional thermal stability and flame ***,the interaction between hydroxyl groups of SiO_(2)particles and PVDF-HFP creates a strong cross-linking structure,enhancing the mechanical strength and stability of the ***,the presence of SiO_(2)aerogel and LLZTO facilitates the dissociation of lithium salts through Lewis acid-base interactions,resulting in a high ionic conductivity of 1.01×10^(−3)S·cm^(−1)and a wide electrochemical window of~5.0 V at room temperature for the prepared ***,the assembled Li|Li cell demonstrates the excellent resistance to lithium dendrite and runs stablly for over 1500 h at a current density of 0.25 mA·cm^(−2).Thus,we prepare a pouch cell with high safety,which can work normally after short-circuiting under the external folding and cutting.

关键词： polymer electrolyte SiO_(2)/Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)dual-filler non-flammable long cycle life lithium metal battery

Vector field path following for a micro flapping-wing robot

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Science China(Information Sciences) 2024年第6期67卷 442-444页

作者： Haifeng huang Yingte LIU Tao NIU chang WANG Yao ZOU Wei HE School of Intelligence Science and Technology University of Science and Technology Beijing Institute of Artificial Intelligence University of Science and Technology Beijing Key Laboratory of Intelligent Bionic Unmanned Systems Ministry of EducationUniversity of Science and Technology Beijing

Flapping-wing robots mimic the flight patterns of natural flying creatures,granting them natural *** hold promising applications in the military reconnaissance,urban surveillance,and various other fields[1–3].However,the current limitations in size often restrict the suitability of existing bird-like flapping-wing robots,

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Study on cumulative effects of biological craniocerebral trauma under repeated blast

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 174-183页

作者： Xingyuan huang Bingchen Xia Lijun chang Zhikang Liao Hui Zhao Zhihua Cai Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment Hunan University of Science and TechnologyXiangtan 411201China School of Mechanical and Electrical Engineering Foshan UniversityFoshan 528231China Institute for Traffic Medicine PLA Army Characteristic Medical CenterChongqing 400042China

Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral *** existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects and cumulative effects of repeated ***,rats were used as the experimental samples to suffer from explosion blasts with different peak air overpressures(167 kPa~482 kPa)and varying number of repeated *** cumulative effect of craniocerebral trauma was most pronounced for moderate repeated blast,showing approximately 95%increase of trauma severity with penta blast,and an approximately 85%increase of trauma severity with penta minor *** cumulative effect of craniocerebral trauma from severe,repeated blast has a smaller rate of change compared to the other two *** severity of trauma from penta blast increased by approximately 69%compared to a single *** physiological,pathological and biochemical analysis show that the degree of neurological trauma caused by repeated blasts is higher than that of single blasts,and the pathological trauma to brain tissue is more extensive and *** trauma degree remains unchanged after double blast,increases by one grade after triple or quadruple blast,and increases by two grades after penta blast.

关键词： Repeated blast Craniocerebral trauma Trauma severity grade Cumulative effects

Three‑dimensional numerical simulation of dynamic strength and failure mode of a rock mass with cross joints

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International Journal of Coal Science & Technology 2024年第2期11卷 35-52页

作者： Tingting Liu Wenxu huang chang Xiang Qian Dong Xinping Li Chao Zhang Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan 430056China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China Hainan Institute Wuhan University of TechnologySanya 572025China

To study the dynamic mechanical properties and failure characteristics of intersecting jointed rock masses with different joint distributions under confining pressure,considering the cross angleαand joint persistence ratioη,a numerical model of the biaxial Hopkinson bar test system was established using the finite element method–discrete-element model coupling *** validity of the model was verified by comparing and analyzing it in conjunction with laboratory test ***-static combined impact tests were conducted on specimens under various conditions to investigate the strength characteristics and patterns of crack initiation and *** study revealed the predominant factors influencing intersecting joints with different angles and penetrations under impact *** results show that the peak stress of the specimens decreases first and then increases with the increase of the cross ***α<60°,regardless of the value ofη,the dynamic stress of the specimens is controlled by the main ***α≥60°,the peak stress borne by the specimens decreases with increasingη.Whenα<60°,the initiation and propagation of cracks in the cross-jointed specimens are mainly controlled by the main joint,and the final failure surface of the specimens is composed of the main joint and wing ***α≥60°orη≥0.67,the secondary joint guides the expansion of the wing cracks,and multiple failure surfaces composed of main and secondary joints,wing cracks,and co-planar cracks are *** lateral confinement significantly increases the dynamic peak stress able to be borne by the *** triaxial conditions,the degree of failure of the intersecting jointed specimens is much lower than that under uniaxial and biaxial conditions.

关键词： Cross joints Joint distribution form Dynamic failure characteristics FEM–DEM BHPB

ess Enhanced photothermoelectric conversion in selfrolled tellurium photodetector with geometryinduced energy localization

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Light(Science & Applications) 2024年第8期13卷 1545-1556页

作者： Jiayuan huang Chunyu You Binmin Wu Yunqi Wang Ziyu Zhang Xinyu Zhang chang Liu Ningge huang Zhi Zheng Tingqi Wu Suwit Kiravittaya Yongfeng Mei Gaoshan huang Department of Materials Science&State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai 200438China Yiwu Research Institute of Fudan University Yiwu 322000 ZhejiangChina International Institute of Intelligent Nanorobots and Nanosystems Fudan UniversityShanghai 200438China ShanghaiTech Quantum Device Lab ShanghaiTech UniversityShanghai 200120China Department of Electrical Engineering Faculty of EngineeringChulalongkorn UniversityBangkokThailand Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception Institute of OptoelectronicsFudan UniversityShanghai 200438China

Photodetection has attracted significant attention for information *** the implementation relies primarily on the photonic detectors,they are predominantly constrained by the intrinsic bandgap of active *** the other hand,photothermoelectric(PTE)detectors have garnered substantial research interest for their promising capabilities in broadband detection,owing to the self-driven photovoltages induced by the temperature *** get higher performances,it is crucial to localize light and heat energies for efficient ***,there is limited research on the energy conversion in PTE detectors at micro/nano *** this study,we have achieved a twoorder-of-magnitude enhancement in photovoltage responsivity in the self-rolled tubular tellurium(Te)photodetector with PTE *** illumination,the tubular device demonstrates a maximum photovoltage responsivity of 252.13 VW^(-1)and a large detectivity of 1.48×10^(11)*** disclose the mechanism of the PTE conversion in the tubular structure with the assistance of theoretical *** addition,the device exhibits excellent performances in wide-angle and polarization-dependent *** work presents an approach to remarkably improve the performance of photodetector by concentrating light and corresponding heat generated,and the proposed self-rolled devices thus hold remarkable promises for next-generation on-chip photodetection.

关键词： illumination energy primarily

Angiosperm-wide analysis of fruit and ovary evolution aided by a new nuclear phylogeny supports association of the same ovary type with both dry and fleshy fruits

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Journal of Integrative Plant Biology 2024年第2期66卷 228-251页

作者： Yezi Xiang Taikui Zhang Yiyong Zhao Hongjin Dong Hongyi Chen Yi Hu chien-Hsun huang Jun Xiang Hong Ma State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity and Ecological EngineeringInstitute of Plant BiologyCenter of Evolutionary BiologySchool of Life SciencesFudan UniversityShanghai 200438China Department of Biology Howard Hughes Medical InstituteDuke UniversityDurhamNC 27708USA Department of Biology the Eberly College of Scienceand the Huck Institutes of the Life Sciencesthe Pennsylvania State UniversityUniversity ParkPA 16802USA Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization College of Biology and Agricultural ResourcesHuanggang Normal UniversityHuanggang 438000China

Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and *** we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain *** this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial *** robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and ***,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple *** of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and *** new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversificat

关键词： angiosperm fruit evolution MADS-box molecular clock nuclear phylogeny ovary and fruit developmental genes

Ultraconformable Integrated Wireless Charging Micro-Supercapacitor Skin

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Nano-Micro Letters 2024年第7期16卷 46-58页

作者： chang Gao Qing You Jiancheng huang Jingye Sun Xuan Yao Mingqiang Zhu Yang Zhao Tao Deng School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China School of Microelectronics Tianjin UniversityTianjin 300072People’s Republic of China Key Laboratory of Cluster Science Ministry of Education of China Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China

Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft ***,current wire-less charging power sources are still restricted by limited flexural angles and fragile connection of components,resulting in the failure expression of performance and constraining their fur-ther applications in health monitoring wearables and moveable artificial ***,we present an ultracompatible skin-like integrated wireless charging micro-supercapacitor,which building blocks(including electrolyte,electrode and substrate)are all evaporated by liquid *** to the infiltration and permeation of the liquid,each part of the integrated device attached firmly with each other,forming a compact and all-in-one *** addition,benefitting from the controllable volume of electrode solution precursor,the electrode thickness is easily regulated varying from 11.7 to 112.5μ*** prepared thin IWC-MSC skin can fit well with curving human body,and could be wireless charged to store electricity into high capacitive micro-supercapacitors(11.39 F cm-3)of the integrated *** believe this work will shed light on the construction of skin-attachable electronics and irregular sensing microrobots.

关键词： Micro-supercapacitor Electronic skin Supercapacitor skin Wireless charging energy storage device