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A Residual Frequency Offset Estimation Method Based on Range Migration Fitting

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Journal of Beijing institute of Technology 2024年第2期33卷 103-110页

作者： Liting Zhang Hao Huan Ran Tao Xiaogang Tang School of Information and electronics Beijing Institute of Technology School of Aerospace Information Space Engineering University

Recently, researchers have proposed an emitter localization method based on passive synthetic aperture. However, the unknown residual frequency offset(RFO) between the transmitter and the receiver causes the received Doppler signal to shift, which affects the localization accuracy. To solve this issue, this paper proposes a RFO estimation method based on range migration fitting. Due to the high frequency modulation slope of the linear frequency modulation(LFM)-modulation radar signal, it is not affected by RFO in range compression. Therefore, the azimuth time can be estimated by fitting the peak value position of the pulse compression in range ***, the matched filters are designed under different RFOs. When the zero-Doppler time obtained by the matched filters is consistent with the estimated azimuth time, the given RFO is the real RFO between the transceivers. The simulation results show that the estimation error of azimuth distance does not exceed 20 m when the received signal duration is not less than 3 s, the pulse repetition frequency(PRF) of the transmitter radar signal is not less than 1 k Hz, the range detection is not larger than 1 000 km, and the signal noise ratio(SNR) is not less than –5 d B.

关键词： range migration fitting (RMF) passive localization residual frequency offset (RFO)

LiDAR-based estimation of bounding box coordinates using Gaussian process regression and particle swarm optimization

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Biomimetic Intelligence & Robotics 2024年第1期4卷 24-35页

作者： Vinodha K. E.S.Gopi Tushar Agnibhoj Department of electronics and Communication Engineering National Institute of Technology TiruchirappalliTamil Nadu620015India

Camera-based object tracking systems in a given closed environment lack privacy and *** this study,light detection and ranging(LiDAR)was applied to track objects similar to the camera tracking in a closed environment,guaranteeing privacy and *** primary objective was to demonstrate the efficacy of the proposed technique through carefully designed experiments conducted using two *** Scenario I,the study illustrates the capability of the proposed technique to detect the locations of multiple objects positioned on a flat surface,achieved by analyzing LiDAR data collected from several locations within the closed *** II demonstrates the effectiveness of the proposed technique in detecting multiple objects using LiDAR data obtained from a single,fixed ***-time experiments are conducted with human subjects navigating predefined *** individuals move within an environment,while LiDAR,fixed at the center,dynamically tracks and identifies their locations at multiple *** demonstrate that a single,strategically positioned LiDAR can adeptly detect objects in motion around ***,this study provides a comparison of various regression techniques for predicting bounding box *** process regression(GPR),combined with particle swarm optimization(PSO)for prediction,achieves the lowest prediction mean square error of all the regression techniques examined at *** tuning of GPR using PSO significantly minimizes the regression *** of the experiment pave the way for its extension to various real-time applications such as crowd management in malls,surveillance systems,and various Internet of Things scenarios.

关键词： LiDAR Data acquisition Bounding box Gaussian process regression Particle swarm optimization(PSO)

Materials and structural design for preferable Zn deposition behavior toward stable Zn anodes

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SmartMat 2024年第1期5卷 1-37页

作者： Qinghe Cao Yong Gao Jie Pu Abdelnaby M.Elshahawy Cao Guan Key Laboratory of Flexible electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical UniversityNingboChina institute of Flexible electronics Northwestern Polytechnical UniversityXi'anChina Department of Physics Faculty of ScienceAssiut UniversityAssiutEgypt

Benefiting from the high capacity of Zn metal anodes and intrinsic safety of aqueous electrolytes,rechargeable Zn ion batteries(ZIBs)show promising application in the post‐lithium‐ion period,exhibiting good safety,low cost,and high energy ***,its commercialization still faces problems with low Coulombic efficiency and unsatisfied cycling performance due to the poor Zn/Zn2+reversibility that occurred on the Zn *** improve the stability of the Zn anode,optimizing the Zn deposition behavior is an efficient way,which can enhance the subsequent striping efficiency and limit the dendrite *** Zn deposition is a controlled kinetics‐diffusion joint process that is affected by various factors,such as the interaction between Zn2+ions and Zn anodes,ion concentration gradient,and current *** this review,from an electrochemical perspective,we first overview the factors affecting the Zn deposition behavior and summarize the modification ***,strategies proposed for interfacial modification and 3D structural design as well as the corresponding mechanisms are ***,the existing challenges,perspectives on further development direction,and outlook for practical applications of ZIBs are proposed.

关键词： 3D structuraldesign interfacialmodification long‐term stability Znanode Zndeposition behavior

Efficient unequal error protection for online fountain codes

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Journal of Systems Engineering and electronics 2024年第2期35卷 286-293页

作者： SHI Pengcheng WANG Zhenyong LI Dezhi LYU Haibo School of electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China

In this paper,an efficient unequal error protection(UEP)scheme for online fountain codes is *** the buildup phase,the traversing-selection strategy is proposed to select the most important symbols(MIS).Then,in the completion phase,the weighted-selection strategy is applied to provide low *** performance of the proposed scheme is analyzed and compared with the existing UEP online fountain *** results show that in terms of MIS and the least important symbols(LIS),when the bit error ratio is 10-4,the proposed scheme can achieve 85%and 31.58%overhead reduction,respectively.

关键词： online fountain code random graph unequal error protection(UEP) rateless code

Surface Patterning of Metal Zinc Electrode with an In‑Region Zincophilic Interface for high‑Rate and Long‑Cycle‑Life Zinc Metal Anode

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Nano-Micro Letters 2024年第6期16卷 192-209页

作者： Tian Wang Qiao Xi Kai Yao Yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova‑Rohlfing Wei Ai Jae Su Yu Department of electronics and Information Convergence Engineering Institute for Wearable Convergence ElectronicsKyung Hee UniversityYongin‑siGyeonggi‑do 17104Republic of Korea Frontiers Science Center for Flexible electronics(FSCFE)and Shaanxi institute of Flexible electronics(SIFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi’an 710072People’s Republic of China institute of Energy and Climate Research:Materials Synthesis and Processing(IEK‑1) Forschungszentrum Julich GmbH52425 JulichGermany School of Chemical Engineering Sungkyunkwan University2066 Seobu‑RoJangan‑GuSuwon‑siGyeonggi‑doRepublic of Korea

The undesirable dendrite growth induced by non-planar zinc(Zn)deposition and low Coulombic efficiency resulting from severe side reactions have been long-standing challenges for metallic Zn anodes and substantially impede the practical application of rechargeable aqueous Zn metal batteries(ZMBs).Herein,we present a strategy for achieving a high-rate and long-cycle-life Zn metal anode by patterning Zn foil surfaces and endowing a Zn-Indium(Zn-In)interface in the *** accumulation of electrons in the microchannel and the zincophilicity of the Zn-In interface promote preferential heteroepitaxial Zn deposition in the microchannel region and enhance the tolerance of the electrode at high current ***,electron aggregation accelerates the dissolution of non-(002)plane Zn atoms on the array surface,thereby directing the subsequent homoepitaxial Zn deposition on the array ***,the planar dendrite-free Zn deposition and long-term cycling stability are achieved(5,050 h at 10.0 mA cm^(−2) and 27,000 cycles at 20.0 mA cm^(−2)).Furthermore,a Zn/I_(2) full cell assembled by pairing with such an anode can maintain good stability for 3,500 cycles at 5.0 C,demonstrating the application potential of the as-prepared ZnIn anode for high-performance aqueous ZMBs.

关键词： Zn metal anode Surface patterning Directional Zn deposition Aqueous Zn-I_(2)batteries

A Modified CycleGAN for Multi-Organ Ultrasound Image Enhancement via Unpaired Pre-Training

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Journal of Beijing institute of Technology 2024年第3期33卷 194-203页

作者： Haonan Han Bingyu Yang Weihang Zhang Dongwei Li Huiqi Li School of Information and electronics Beijing Institute of TechnologyBeijing 100081China School of Medical Technology Beijing Institute of TechnologyBeijing 100081China

Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early ***,the image quality of handheld ultrasound devices is not always satisfactory due to the limited equipment size,which hinders accurate diagnoses by *** the same time,paired ultrasound images are difficult to obtain from the clinic because imaging process is ***,we propose a modified cycle generative adversarial network(cycleGAN) for ultrasound image enhancement from multiple organs via unpaired *** introduce an ultrasound image pre-training method that does not require paired images,alleviating the requirement for large-scale paired *** also propose an enhanced block with different structures in the pre-training and fine-tuning phases,which can help achieve the goals of different training *** improve the robustness of the model,we add Gaussian noise to the training images as data *** approach is effective in obtaining the best quantitative evaluation results using a small number of parameters and less training costs to improve the quality of handheld ultrasound devices.

关键词： ultrasound image enhancement handheld devices unpaired images pre-train and finetune cycleGAN

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

All-optical suppression on the impact of Sun outage in laser satellite communication systems by using a nonlinear semiconductor optical amplifier

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Chinese Optics Letters 2024年第2期22卷 76-80页

作者：李晓亮刘荣科范峰 School of electronics and Information Engineering Beihang UniversityBeijing 100191China Beijing Research institute of Telemetry Beijing 100094China

We introduce an all-optical approach,optical parametric amplification(OPA)processor to suppress the impact of Sun outage in laser satellite communication systems,which is implemented by only one nonlinear semiconductor optical amplifier driven by both electrical and optical *** optimized OPA processor,with a current of 539 mA and a pump-to-signal ratio of 16 dB,could significantly improve the signal quality by 3.5 dB in experiments for the elevation angle of Sun radiation of 0 *** signal quality improvement is observed in the whole range of the elevation angle,confirming the effectiveness of the proposed OPA processor in the field of Sun radiation mitigation.

关键词： nonlinear optics Sun outage laser satellite communication

A universal calibration method for eliminating topographydependent current in conductive AFM and its application in nanoscale imaging

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Nano Research 2024年第7期17卷 6509-6517页

作者： Chunlin Hao Hao Xu Shiquan Lin Yaju Zhang Jinmiao He Bei Liu Yuanzheng Zhang Banghao Wu Guozhen Shen Haiwu Zheng Henan Province Engineering Research Center of Smart Micro-nano Sensing Technology and Application School of Physics and ElectronicsHenan UniversityKaifeng 475004China School of Integrated Circuits and electronics Beijing Institute of TechnologyBeijing 100081China Beijing institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China

The topography and electrical properties are two crucial characteristics that determine the roles and functionalities of *** atomic force microscopy(CAFM)is widely recognized for its ability to independently measure the topography and *** increasing trend towards miniaturization in electrical devices and sensors has encouraged an urgent demand for enhancing the accuracy of CAFM ***,when performing CAFM tests on Bi_(0.5)Na_(0.5)TiO_(3)bulk ceramic,it is interesting to observe significant currents related to the *** do insulators exhibit“conductivity”in CAFM testing?Herein,we thoroughly investigated the topography-dependent current during CAFM testing for the first *** on the linear dependence between the current and the first derivative of topography,the calibration method has been proposed to eliminate the topographic *** method is evaluated on Bi_(0.5)Na_(0.5)TiO_(3)bulk ceramic,one-dimensional(1D)ZnO nanowire,twodimensional(2D)NbOI_(2)flake,and biological lotus *** corresponding results of negligible topography-interference current affirm the feasibility and universality of this calibration *** work effectively addresses the challenge of topographic crosstalk in CAFM characterization,thereby preventing the erroneous estimation of the conductivity of any unknown sample.

关键词： conductive atomic force microscopy topographic crosstalk current error calibration method