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Chinese Journal of Aeronautics 2024年第5期37卷 349-362页

作者： Zhengjie LI Yujie WEI Junwei XIE Haowei ZHANG Yu TIAN Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Xi’an Flying College Xi’an 710300China Air and Missile Defense Institute Air Force Research InstituteBeijing 100085China School of Economics and Management Beihang UniversityBeijing 100191China

This paper investigates the problem of Joint Radar Node Selection and Power Allocation(JRNSPA)in the Multiple Radar System(MRS)in the blanket jamming *** radar node independently tracks moving target and subsequently transmits the raw observation data to the fusion center,which formulates a centralized tracking network *** order to establish a practical blanket jamming environment,we suppose that each target carries the self-defense jammer which automatically implements blanket jamming to the radar nodes that exceed the preset interception ***,the Predicted Conditional Cramer-Rao Lower Bound(PC-CRLB)is derived and utilized as the tracking accuracy *** at ensuring both the tracking performance and the Low Probability of Intercept(LPI)performance,the resource-saving scheduling model is formulated to minimize the transmit power consumption while meeting the requirements of tracking ***,the Modified Zoutendijk Method Of Feasible Directions(MZMFD)-based two-stage solution technique is adopted to solve the formulated non-convex optimization *** results show the effectiveness of the proposed JRNSPA scheme.

关键词： Multiple Radar System(MRS) Centralized target tracking Resource scheduling Blanket jamming Low Probability of Intercept(LPI)

Probing the Nucleation and Growth Kinetics of Bismuth Nanoparticles via In-situ Transmission Electron Microscopy

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 877-887页

作者：王浪李超凡 RAN Maojin YUAN Manman 胡执一 LI Yu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Nanostructure Research Centre(NRC) Wuhan University of TechnologyWuhan 430070China Institute of Chemistry Henan Academy of SciencesZhengzhou 450002China Henan Academy of Sciences Zhengzhou 450046China

The nucleation and growth mechanism of nanoparticles is an important theory,which can guide the preparation of ***,it is still lacking in direct observation on the details of the evolution of intermediate state structure during nucleation and *** this work,the evolution process of bismuth nanoparticles induced by electron beam was revealed by in-situ transmission electron microscopy(TEM)at atomic *** experimental results demonstrate that the size,stable surface and crystallographic defect have important influences on the growth of Bi *** non-classical growth paths including single crystal growth and polycrystalline combined growth,as well as,corresponding layer-by-layer growth mechanism along{012}stable crystal plane of Bi nanoparticles with dodecahedron structure were revealed by in-situ TEM *** results provide important guidance and a new approach for in-depth understanding of the nucleation and growth kinetics of nanoparticles.

关键词： bismuth nanoparticles crystal growth transmission electron microscopy in-situ electron microscopy

An Opposition-Based Learning-Based Search Mechanism for Flying Foxes Optimization Algorithm

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Computers, Materials & Continua 2024年第6期79卷 5201-5223页

作者： Chen Zhang Liming Liu Yufei Yang Yu Sun Jiaxu Ning Yu Zhang Changsheng Zhang Ying Guo Software College Northeastern UniversityShenyang110169China School of Information Science and Engineering Shenyang Ligong UniversityShenyang110159China china Telecom Digital Intelligence Technology Co. Ltd.Beijing100035China College of Computer Science and Engineering Ningxia Institute of Science and TechnologyShizuishan753000China

The flying foxes optimization(FFO)algorithm,as a newly introduced metaheuristic algorithm,is inspired by the survival tactics of flying foxes in heat wave *** preferentially selects the best-performing *** tendency will cause the newly generated solution to remain closely tied to the candidate optimal in the search *** address this issue,the paper introduces an opposition-based learning-based search mechanism for FFO algorithm(IFFO).Firstly,this paper introduces niching techniques to improve the survival list method,which not only focuses on the adaptability of individuals but also considers the population’s crowding degree to enhance the global search ***,an initialization strategy of opposition-based learning is used to perturb the initial population and elevate its ***,to verify the superiority of the improved search mechanism,IFFO,FFO and the cutting-edge metaheuristic algorithms are compared and analyzed using a set of test *** results prove that compared with other algorithms,IFFO is characterized by its rapid convergence,precise results and robust stability.

关键词： Flying foxes optimization(FFO)algorithm opposition-based learning niching techniques swarm intelligence metaheuristics evolutionary algorithms

The First Total Synthesis of Natural 6β-Cinnamoyloxy-1α- hydroxy-5, 10-bis-epi-eudesm-4-en-3-one

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Chinese Chemical Letters 2006年第10期17卷 1290-1292页

作者： Chen ZHANG Guo Jun ZHEN Jin Chun CHEN Li Jing FANG Yu Lin LI State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one （1）, a highly complex natural eudesmane, was described.

关键词： 6β-Cinnamoyloxy-1α-hydroxy-5,10-bis-epi-eudesm-4-en-3-one C- 1 oxygenated eudesmane total synthesis.

Optimal search path planning of UUV in battlefeld ambush scene

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Defence Technology（防务技术） 2024年第2期32卷 541-552页

作者： Wei Feng Yan Ma Heng Li Haixiao Liu Xiangyao Meng Mo Zhou Naval Research Institute Beijing100161China

Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean ***,by establishing these mathematical models of ocean current environment,target movement,and sonar detection,the probability calculation methods of single UUV searching target and multiple UUV cooperatively searching target are given ***,based on the Hybrid Quantum-behaved Particle Swarm Optimization(HQPSO)algorithm,the path with the highest target search probability is ***,through simulation calculations,the influence of different UUV parameters and target parameters on the target search probability is analyzed,and the minimum number of UUVs that need to be deployed to complete the ambush task is demonstrated,and the optimal search path scheme is *** method proposed in this paper provides a theoretical basis for the practical application of UUV in the future combat.

关键词： Battlefield ambush Optimal search path planning UUV path Planning Probability of cooperative search

Model based on single-nucleotide polymorphism to discriminate aspirin resistance patients

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Stroke & Vascular Neurology 2024年第3期9卷 212-220,I0110-I0129页

作者： Qingyuan Liu Shuaiwei Guo Nuochuan Wang Kaiwen Wang Shaohua Mo Xiong Li Yanan Zhang Hongwei He Shuo Wang Jun Wu Department of Neurosurgery and china National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalBeijingChina Department of Blood Transfusion Beijing Tiantan HospitalBeijingChina Department of Neurosurgery Beijing Chao-Yang Hospital Capital Medical UniversityBeijingChina Beijing Neurosurgical institution Capital Medical UniversityBeijingChina

Background Aspirin is widely used for preventing ischaemic *** 20%–40%of patients have aspirin resistance(ASR),which prevents them from benefiting from aspirin *** study aimed to develop and validate a model based on single-nucleotide polymorphism(SNP)to distinguish ASR *** We included patients with spontaneous intracerebral haemorrhage and continuing antiplatelet therapy from a multicentre,prospective cohort study as the derivation ***(inhibition of arachidonic acid channel<50%)was used to identify *** was performed to identify the ASR-related *** on the result of the logistic analysis,the aspirin resistance in the Chinese population score(ASR-CN score)was established,and its accuracy was evaluated using the area under the curve(AUC).Patients receiving dual antiplatelet therapy for unruptured intracranial aneurysm embolism were prospectively included in the validation *** embolism,30-day ischaemic events,including ischaemic stroke,new or more frequent transient ischaemic attack,stent thrombosis and cerebrovascular death,were *** The derivation cohort included 212 patients(155 male patients and the median age as 59).87(41.0%)individuals were identified with *** multivariate logistic analysis demonstrated six SNPs of GP1BA,TBXA2R,PTGS2 and NOS3 as risk factors related to *** ASR-CN score integrating these SNPs performed well to discriminate ASR patients from non-ASR patients(AUC as 0.77).Based on the validation cohort of 372 patients receiving antiplatelet therapy after embolism(including 130 ASR patients),the ASR-CN score continued to distinguish ASR patients with good accuracy(AUC as 0.80).Patients with high a ASR-CN score were more likely to suffer from 30-day ischaemic events after embolism(OR,1.28;95%CI,1.10 to 1.50;p=0.002).Conclusion GP1BA,TBXA2R,PTGS2 and NOS3 were SNPs related to *** ASR-CN score is an effective tool to discriminate ASR patients,which

关键词： patients aspirin resistance

Relationships between Terrain Features and Forecasting Errors of Surface Wind Speeds in a Mesoscale Numerical Weather Prediction Model

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Advances in Atmospheric Sciences 2024年第6期41卷 1161-1170页

作者： Wenbo XUE Hui YU Shengming TANG Wei HUANG Chinese Academy of Meteorological Sciences Beijing 100081China University of Chinese Academy of Sciences Beijing 101408China Shanghai Typhoon Institute/CMA Shanghai 200030China Key Laboratory of Numerical Modeling for Tropical Cyclone/CMA Shanghai 200030China

Numerical weather prediction(NWP)models have always presented large forecasting errors of surface wind speeds over regions with complex *** this study,surface wind forecasts from an operational NWP model,the SMS-WARR(Shanghai Meteorological Service-WRF ADAS Rapid Refresh System),are analyzed to quantitatively reveal the relationships between the forecasted surface wind speed errors and terrain features,with the intent of providing clues to better apply the NWP model to complex terrain *** terrain features are described by three parameters:the standard deviation of the model grid-scale orography,terrain height error of the model,and slope *** results show that the forecast bias has a unimodal distribution with a change in the standard deviation of *** minimum ME(the mean value of bias)is 1.2 m s^(-1) when the standard deviation is between 60 and 70 m.A positive correlation exists between bias and terrain height error,with the ME increasing by 10%−30%for every 200 m increase in terrain height *** ME decreases by 65.6%when slope angle increases from(0.5°−1.5°)to larger than 3.5°for uphill winds but increases by 35.4%when the absolute value of slope angle increases from(0.5°−1.5°)to(2.5°−3.5°)for downhill *** sensitivity experiments are carried out with a model output statistical(MOS)calibration model for surface wind speeds and ME(RMSE)has been reduced by 90%(30%)by introducing terrain parameters,demonstrating the value of this study.

关键词： surface wind speed terrain features error analysis MOS calibration model

Filterless Photosensors with Intrinsic Color Perception and Flexibility

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Chemical Research in Chinese Universities 2024年第5期40卷 894-900页

作者： ZHOU Hongtao XU Beihang ZHENG Xinjia GONG Jinchao ZHANG Kaitong HE Yonglin Key Laboratory of Advanced Light Conversion Materials and Biophotonics School of Chemistry and Life ResourcesRenmin University of ChinaBeijing100872P.R.China School of Mathematics Renmin University of ChinaBeijing100872P.R.China

Sensing materials possessing intrinsic color perception are indispensable prerequisites for the development of filterless photosensors,which could eliminate the need for complex device designs and avoid color distortion in *** materials are constrained by complex processing methods and limited ***,a color-photosensitive array based on ionic liquid with selective photothermal conversion(ILSPC)has been developed for intrinsic color *** on the selective absorption,photothermal conversion,and thermosensitivity of ILSPC,a photo-thermo-electric sensing system has been ***,the versatility of the two algorithms has been validated in color reconstruction and electrical signal *** an exploration,the photosensitive array showcases promising color recognition capabilities,potentially propelling the evolution of flexible photosensors.

关键词： Ionic liquid Filterless Intrinsic color perception Selective photothermal conversion Photosensitive array

Building a High-Performance Graph Storage on Top of Tree-Structured Key-Value Stores

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Big Data Mining and Analytics 2024年第1期7卷 156-170页

作者： Heng Lin Zhiyong Wang Shipeng Qi Xiaowei Zhu Chuntao Hong Wenguang Chen Yingwei Luo School of Computer Science Peking UniversityBeijing 100871China Ant Group Beijing 100020China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Graph databases have gained widespread adoption in various industries and have been utilized in a range of applications,including financial risk assessment,commodity recommendation,and data lineage *** the principles and design of these databases have been the subject of some investigation,there remains a lack of comprehensive examination of aspects such as storage layout,query language,and *** present study focuses on the design and implementation of graph storage layout,with a particular emphasis on tree-structured key-value *** also examine different design choices in the graph storage layer and present our findings through the development of TuGraph,a highly efficient single-machine graph database that significantly outperforms well-known Graph DataBase Management System(GDBMS).Additionally,TuGraph demonstrates superior performance in the Linked Data Benchmark Council(LDBC)Social Network Benchmark(SNB)interactive benchmark.

关键词： graph database high-performance graph storage

Dual-objective two-photon microscope for volumetric imaging of dense scattering biological samples by bidirectional excitation and collection

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Photonics Research 2024年第6期12卷 1351-1361页

作者： MUYUE ZHAI JING YU YANHUI HU HANG YU BEICHEN XIE YI YU DAWEI LI AIMIN WANG HEPING CHENG National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Research Unit of Mitochondria in Brain Diseases Chinese Academy of Medical SciencesPKU-Nanjing Institute of Translational MedicineNanjing 211500China Beijing Transcend Vivoscope Biotech Beijing 100085China College of Engineering Peking UniversityBeijing 100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China Center for Quantitative Biology Peking UniversityBeijing 100871China School of Electronics Peking UniversityBeijing 100871China State Key Laboratory of Advanced Optical Communication System and Networks Peking UniversityBeijing 100871China

Full view observation throughout entire specimens over a prolonged period is crucial when exploring the physiological functions and system-level ***-photon microscopy(MPM)has been widely employed for such purposes owing to its deep penetration ***,the current MPM struggles with balancing the imaging depth and quality while avoiding photodamage for the exponential increasement of excitation power with the imaging ***,we present a dual-objective two-photon microscope(Duo-2P),characterized by bidirectional two-photon excitation and fluorescence collection,for long-duration volumetric imaging of dense scattering ***-2P effectively doubles the imaging depth,reduces the total excitation energy by an order of magnitude for samples with a thickness five times the scattering length,and enhances the signal-to-noise ratio up to 1.4 *** these advantages,we acquired volumetric images of a 380-μm suprachiasmatic nucleus slice for continuous 4-h recording at a rate of 1.67 s/volume,visualized the calcium activities over 4000 neurons,and uncovered their state-switching *** conclude that Duo-2P provides an elegant and powerful means to overcome the fundamental depth limit while mitigating photodamages for deep tissue volumetric imaging.

关键词： excitation overcome exponential