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High-Precision DOA Estimation Method Based on Synthetic Aperture Technique

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Journal of Beijing Institute of Technology 2024年第2期33卷 111-118页

作者： Yongjia Dou Guangcai Sun yuqi wang Mengdao Xing National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China School of Communication and Information Engineering Xi’an University of Science and TechnologyXi’an 710054China

The existing direction-of-arrival(DOA)estimation methods only utilize the current received signals,which are susceptible to *** this paper,a method for DOA estimation based on a motion platform is proposed to achieve high-precision DOA estimation by utilizing past and present *** concept of synthetic aperture is introduced to construct a linear DOA estima-tion model.A DOA fine-tuning method based on the linear model is proposed to eliminate the lin-ear DOA variation,achieving a non-coherent accumulation of DOA ***,the baseband modulation and the phase modulation caused by the range history are compensated to achieve the coherent accumulation of all the DOA *** results show that the proposed method can significantly improve the DOA estimated accuracy at low signal-to-noise ratios(SNR).

关键词： synthetic aperture direction-of-arrival(DOA)estimation coherent accumulation

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Emergence of machine language: towards symbolic intelligence with neural networks

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National Science Review 2024年第4期11卷 27-30页

作者： yuqi wang Xu-Yao Zhang Cheng-Lin Liu Tieniu Tan Zhaoxiang Zhang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Representation learning is a core issue in artificial intelligence (AI). Currently,there exists a disparity in the choice of representation between humans and machines. Humans rely on discrete language for communicati...

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Keplerate polyoxomolybdate nanoball mediated controllable preparation of metal-doped molybdenum disulfide for electrocatalytic hydrogen evolution in acidic and alkaline media

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Chinese Chemical Letters 2024年第7期35卷 524-528页

作者： Ping wang Ting wang Ming Xu Ze Gao Hongyu Li Bowen Li yuqi wang Chaoqun Qu Ming Feng Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China School of Science Changchun University of Science and TechnologyChangchun 130022China

Rationally designed novel cost-effective hydrogen evolution reaction(HER)electrocatalysts with controlled surface composition and advanced structural superiority is extremely critical to optimize the HER ***(POMs)with structural diversity and adjustable element compositions represent a promising precursor for rational design and preparation of HER ***,a series of transition metal-doped MoS_(2)materials with different surface engineered structures(Fe,Cr,V doping and S vacancies)(M-MoS_(2)/CC,M=Fe,Cr and V)were fabricated by a simple hydrothermalvulcanization strategy using Keplerate polyoxomolybdate nanoball({Mo_(72)Fe_(30)},{Mo_(72)Cr_(30)},{Mo_(72)V_(30)},{Mo_(132)})as *** enlarged interlayer spacing as well as the integration of homogeneous transition metal doping and abundant sulfur vacancies endows prepared M-MoS_(2)/CC with superior HER electrocatalytic performance and excellent long-term working stability in both acidic and alkaline *** optimized Fe-MoS_(2)/CC afford current densities of 10 and 50 mA/cm^(2)at overpotentials of 188/272 mV and 194/394 mV in 0.5 mol/L H_(2)SO_(4)and 1.0 mol/L KOH aqueous solution,respectively,outperforming most of reported typical transition metal sulfide-based *** work represents an important breakthrough for POMs-mediated highly efficient transition metal sulfide-based HER electrocatalysts with wide range pH activity and may provide new options for the rational design of promising HER electrocatalysts and beyond.

关键词： Polyoxometalate Electrocatalytic Hydrogen evolution reaction Doping MoS_(2)

Knockout of C6orf120 in Rats Alleviates Concanavalin A-induced Autoimmune Hepatitis by Regulating Macrophage Polarization

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Biomedical and Environmental Sciences 2024年第6期37卷 594-606页

作者： Xin wang yuqi wang Hui Liu Yingying Lin Peng wang Yunyun Yi Xin Li Department of Center of Integrated Traditional Chinese and Western Medicine Peking University Ditan Teaching HospitalBeijing 100015China Department of Center of Integrated Traditional Chinese and Western Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Center of Infectious Disease Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

Objective The effect of the functionally unknown gene C6orf120 on autoimmune hepatitis was investigated on C6orf120 knockout rats(C6orf120^(-/-))and THP-1 *** Six–eight-week-old C6orf120^(-/-)and wild-type(WT)SD rats were injected with Con A(16 mg/kg),and euthanized after 24 *** sera,livers,and spleens were ***-1 cells and the recombinant protein(rC6ORF120)were used to explore the mechanism in *** frequency of M1 and M2 macrophages was analyzed using flow *** blotting and PCR were used to detect macrophage polarization-associated *** C6orf120 knockout attenuated Con A-induced autoimmune *** cytometry indicated that the proportion of CD68^(+)CD86^(+)M1 macrophages from the liver and spleen in the C6orf120^(-/-)rats decreased.C6orf120 knockout induced downregulation of CD86 protein and the mRNA levels of related inflammatory factors TNF-α,IL-1β,and IL-6 in the liver.C6orf120 knockout did not affect the polarization of THP-1 ***,rC6ORF120 promoted the THP-1 cells toward CD68^(+)CD80^(+)M1 macrophages and inhibited the CD68^(+)CD206^(+)M2 *** C6orf120 knockout alleviates Con A-induced autoimmune hepatitis by inhibiting macrophage polarization toward M1 macrophages and reducing the expression of related inflammatory factors in C6orf120^(-/-)rats.

关键词： C6orf120 Autoimmune hepatitis Macrophage polarization M1 macrophages

Emerging probing perspective of two-dimensional materials physics:terahertz emission spectroscopy

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Light(Science & Applications) 2024年第7期13卷 1278-1298页

作者： Yifei Wu yuqi wang Di Bao Xiaonan Deng Simian Zhang Lin Yu-chun Shengxian Ke Jianing Liu Yingjie Liu Zeli wang Pingren Ham Andrew Hanna Jiaming Pan Xinyue Hu Zhengcao Li Ji Zhou Chen wang State Key Laboratory of New Ceramics and Fine Processing Key Laboratory of Advanced Materials of Ministry of EducationSchool of Materials Science and EngineeringTsinghua University100084 BeijingChina Beijing Advanced Innovation Center for Integrated Circuits 100084 BeijingChina

Terahertz(THz)emission spectroscopy(TES)has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few ***,research on two-dimensional(2D)materials has experienced substantial growth due to their atomically thin structures,exceptional mechanical and optoelectronic properties,and the potential for applications in flexible electronics,sensing,and ***,these materials offer advantages such as tunable bandgap,high carrier mobility,wideband optical absorption,and relatively short carrier *** applying TES to investigate the 2D materials,their interfaces and heterostructures,rich information about the interplay among photons,charges,phonons and spins can be unfolded,which provides fundamental understanding for future *** it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification,photon-drag,high-order harmonic generation and spin-to-charge conversion,showcasing the rich diversity of the TES employed to unravel the complex nature of these *** applications based on THz emissions,such as THz lasers,ultrafast imaging and biosensors,are also *** further,we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth,high power and integration,suitable for industrial and commercial *** continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas,including basic materials physics,novel optoelectronic devices,and chips for post-Moore’s era.

关键词： optoelectronic versatile exceptional

Synthetic Aperture Positioning: A Review

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Journal of Beijing Institute of Technology 2024年第2期33卷 89-102页

作者： Guangcai Sun Wenlong Dong yuqi wang Mengdao Xing National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China School of Communication and Information Engineering Xi’an University of Science and TechnologyXi’an 710054China National Key Laboratory of Radar Signal Processing and the Academy of Advanced Interdisciplinary Research DepartmentXidian UniversityXi’an 710071China

Obtaining precise position of interested emitters passively has wide applications in both civilian and military *** from traditional parameter measurement and direct position determination(DPD)method,recently a new passive localization method based on synthetic aper-ture technique,named synthetic aperture positioning(SAP),has been *** method com-pensates for the nonlinear phase produced by relative motion between the moving platform and the emitter,achieving coherent summation of intercepted *** SAP can obtain high-resolution and high-precision localization results at a low signal-to-noise *** paper summarizes the research progress of SAP,including localization principles,spaceborne applications,and application scope ***,the possible future outlook of SAP is considered.

关键词： passive localization synthetic aperture positioning coherent processing

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Multifunctional interfacial molecular bridge enabled by an aggregation-induced emission strategy for enhancing efficiency and UV stability of perovskite solar cells

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Journal of Energy Chemistry 2024年第8期95卷 588-595,I0013页

作者： Shuhang Bian yuqi wang Fancong Zeng Zhongqi Liu Bin Liu Yanjie Wu Long Shao Yongzhi Shao Huan Zhang Shuainan Liu Jin Liang Xue Bai Lin Xu Donglei Zhou Biao Dong Hongwei Song State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012JilinChina College of Science Shanghai UniversityShanghai 200444China

The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H_(8)ETTB)at the SnO_(2)ETL/perovskite ***,the interaction of H_(8)ETTB with the SnO_(2)surface,facilitated by its carboxyl groups,is effective in passivating surface defects caused by noncoord inated Sn and O *** interaction enhances the conductivity of the SnO_(2)film and adjusts energy levels,leading to enhanced charge carrier ***,H_(8)ETTB can passivate noncoord inated Pb^(2+)ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline *** importantly,the H_(8)ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of ***,the champion PSC based on SnO_(2)-H_(8)ETTB achieves an impressing efficiency of 23.32%and significantly improved photostability compared with the control device after continuous exposure to intense UV *** addition,the Cs_(0.05)(FA_(0.95)MA_(0.05))_(0.95)Pb(I_(0.95)Br_(0.05))_(3)based device can achieve maximum efficiency of 24.01%,demonstrating the effectiveness and universality of this ***,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs.

关键词： Perovskite solar cells Aggregation-induced emission Defect passivation Efficiency UV stability

The response of Martian photoelectron boundary to the 2018 global dust storm

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Science China Earth Sciences 2024年

作者： yuqi wang Jun CUI Yong WEI Zhaopeng WU Kai FAN Zhaojin RONG Fei HE Yutian CAO Jiawei GAO Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Planetary Environmental and Astrobiological Research Laboratory (PEARL) School of Atmospheric Sciences Sun Yat-sen University Center for Excellence in Comparative Planetology Chinese Academy of Sciences

Extensive research efforts have revealed that the Martian dust storms can perturb the upper atmospheric condition and as a consequence, enhance plasma density and photoelectron flux in the ionosphere. However, previous observational studies of the Martian dust storm impacts have been restricted to regions below 400 km, which limits our understanding of the Martian dust storm effects in the upper ionosphere and magnetosphere. Here, based on the suprathermal electron measurements made by the Solar Wind Electron Analyzer onboard the Mars Atmosphere and Volatile Evolution, we identify with an automatic procedure the occurrences of all photoelectron boundary (PEB) crossings at solar zenith angle below 120°(with a dust-free median altitude of about 600 km). Using the dayside PEB as a proxy of the upper ionospheric and magnetospheric condition, we analyze the variations of the PEB altitude during the 2018 global dust storm (GDS) of Mars Year 34 (MY34) and compare them with the period in MY33 when there was no global dust storm. We conclude that the column dust optical depth (CDOD) emerges as one of the main driving factors for PEB altitude variations during the GDS. Our analysis implies that the GDS can affect the Martian upper atmosphere and ionosphere over considerable distances and extended time scales.

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大弦戏弦索腔“细曲”的音乐结构与曲调派生

中央音乐学院学报 2024年第2期 39-52页

作者：王宇琪中央音乐学院

大弦戏是弦索声腔的代表性剧种,其唱腔曲牌有粗、细之分。细曲风格典雅,具有“散序—拍序—交句—入变—煞尾”较为稳定的音乐结构,粗曲短小通俗,多由细曲派生。这些曲牌常与南北曲同名,却在唱词格律、旋律音调等方面表现出不同于南北... 详细信息

大弦戏是弦索声腔的代表性剧种,其唱腔曲牌有粗、细之分。细曲风格典雅,具有“散序—拍序—交句—入变—煞尾”较为稳定的音乐结构,粗曲短小通俗,多由细曲派生。这些曲牌常与南北曲同名,却在唱词格律、旋律音调等方面表现出不同于南北曲的特质,并在粗、细曲牌间建立起共同的音乐“基因”,体现出弦索声腔曲牌的独特面貌。该剧种保存了极有价值的民间乐语与古老的音乐样态,是我国戏曲音乐的宝贵财富。

关键词：大弦戏弦索声腔细曲粗曲音乐结构