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Inversion of maize leaf nitrogen using UAV hyperspectral imagery in breeding fields

International Journal of Agricultural and Biological Engineering 2024年第3期17卷 144-155页

作者： Qiwen Cheng Bingsun Wu Huichun Ye Yongyi Liang Yingpu Che Anting Guo Zixuan Wang Zhiqiang Tao Wenwei Li Jingjing Wang School of Tropical Agriculture and Forestry Hainan UniversityHaikou 570228China Rubber research Institute Chinese Academy of Tropical Agricultural SciencesHaikou 571101China Key Laboratory of Earth Observation of Hainan Province Hainan Aerospace Information Research InstituteSanya 572029HainanChina Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China Institute of Crop Science Chinese Academy of Agricultural SciencesBeijing 100081China

Nitrogen(N)as a pivotal factor in influencing the growth,development,and yield of *** the N status of maize rapidly and non-destructive and real-time is meaningful in fertilization management of agriculture,based on unmanned aerial vehicle(UAV)remote sensing *** this study,the hyperspectral images were acquired by UAV and the leaf nitrogen content(LNC)and leaf nitrogen accumulation(LNA)were measured to estimate the N nutrition status of maize.24 vegetation indices(VIs)were constructed using hyperspectral images,and four prediction models were used to estimate the LNC and LNA of *** models include a single linear regression model,multivariable linear regression(MLR)model,random forest regression(RFR)model,and support vector regression(SVR)***,the model with the highest prediction accuracy was applied to invert the LNC and LNA of maize in breeding *** results of the single linear regression model with 24 VIs showed that normalized difference chlorophyll(NDchl)had the highest prediction accuracy for LNC(R^(2),RMSE,and RE were 0.72,0.21,and 12.19%,respectively)and LNA(R^(2),RMSE,and RE were 0.77,0.26,and 14.34%,respectively).And then,24 VIs were divided into 13 important VIs and 11 unimportant *** prediction models for LNC and LNA were constructed using 13 important VIs,and the results showed that RFR and SVR models significantly enhanced the prediction accuracy of LNC and LNA compared to the multivariable linear regression model,in which RFR model had the highest prediction accuracy for the validation dataset of LNC(R^(2),RMSE,and RE were 0.78,0.16,and 8.83%,respectively)and LNA(R^(2),RMSE,and RE were 0.85,0.19,and 9.88%,respectively).This study provides a theoretical basis for N diagnosis and precise management of crop production based on hyperspectral remote sensing in precision agriculture.

关键词： maize nitrogen hyperspectral imagery vegetation index UAV random forest regression support vector regression

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Fortifying Smart Grids: A Holistic Assessment Strategy against Cyber Attacks and Physical Threats for Intelligent Electronic Devices

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Computers, Materials & Continua 2024年第8期80卷 2579-2609页

作者： Yangrong Chen June Li Yu Xia Ruiwen Zhang Lingling Li Xiaoyu Li Lin Ge School of Computer Science Zhengzhou University of AeronauticsZhengzhou450046China Henan Xin’an Century Technology Co. Ltd.Henan Data Security Engineering Technology Research CenterZhengzhou450046China Key Laboratory of aerospace information Security and Trusted Computing Ministry of EducationSchool of Cyber Science and EngineeringWuhan UniversityWuhan430072China

Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control *** the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication *** grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for ***,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for ***,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security ***,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal *** index system contains 18 indicators in 3 ***,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and *** higher the level,the greater the security ***,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by *** results show that calculated security risk level based on the proposed assessment method are consistent with actual ***,the reasonableness and effectiveness of the proposed index system and assessment method are validated.

关键词： Smart grid intelligent electronic device security assessment abnormal behaviors network traffic running states

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Analytical solutions for full-field radiations of magnetoelectric antennas with nonlinear magnetoelastic coupling

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Acta Mechanica Sinica 2024年第7期40卷 109-121页

作者： Baoxin Lei Zhixiong You Zhidong Zhang Yang Shi research center for Applied Mechanics School of Mechano-Electronic EngineeringXidian UniversityXi'an 710071China China Telecom WanWei information Technology Co. Ltd.Lanzhou 730010China

This paper presents analytical solutions for full-field radiation in magnetoelectric(ME)antennas,considering a fully magnetoelastic coupled constitutive relation.A nonlinear converse ME coupling model is established,incorporating mechanical,electric,and magnetic variables with generalized Maxwell *** model emphasizes the essence of ME antennas,where radiation is achieved through strain/stress-mediated coupling between different *** magnetic flux density and electric displacement obtained from the model are used as sources to solve the full-field radiations of ME *** proposed model is validated through existing experiments and simulations,demonstrating that the radiation performance of ME antennas is strongly influenced by nonlinear magneto-elastic *** material parameters and magnetic bias significantly impact the magnetic flux density and far-field radiation due to the nonlinear magnetization *** study reveals the mechanisms behind enhanced working bandwidth and frequency tuning by examining the frequency response of the radiation impedance with material *** adjusting the initial magnetization rate,saturation magnetostriction,and saturation magnetization,the radiation efficiency/gain can be increased by 340%,108%,and 112%*** model enhances our understanding of the full-field radiation of ME antennas and provides a foundation for designing tunable ME antennas.

关键词： ME antenna Full-field radiation Magneto-elastic coupling Radiation patterns

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Spatial-temporal variations of surface water area during 1986-2018 in Qinghai Province,northwestern China based on Google Earth Engine

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Big Earth Data 2024年第2期8卷 333-349页

作者： Luying Zhu Haifeng Tian Ni Huang Li Wang Zheng Niu State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina College of Geography and Environmental Science Henan UniversityKaifengChina

Called the“Water Tower”,the water resource in Qinghai Province plays a vital role in the ecological environment of northwestern ***,significant uncertainty exists regarding its spatialtemporal *** this study,the data on the surface water of Qinghai Province from 1986 to 2018 was extracted and a systemic analysis of its spatial-temporal variations and responses to climate change was conducted using the Google Earth Engine(GEE)cloud processing *** findings revealed that the surface water in Qinghai Province was primarily concentrated in the Qaidam Basin,the Hoh Xil Nature Reserve,and Qinghai *** surface water area in Qinghai Province exhibited an overall increasing trend,with the temperature and precipitation being the primary drivers of this *** results provide crucial insights into the variations of surface water variations in Qinghai Province,northwestern China,under the influence of climate change.

关键词： Qinghai Province Google Earth Engine surface water climate change

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The Investigation of Data Voting Algorithm for Train Air-Braking System Based on Multi-Classification SVM and ANFIS

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Chinese Journal of Electronics 2024年第1期33卷 274-281页

作者： Juhan WANG Ying GAO Yuan CAO Tao TANG School of Electronics and information Engineering Beijing Jiaotong University Graduate Department China Academy of Railway Science National Engineering research center of Rail Transportation Operation and Control System Beijing Jiaotong University

The pressure data of the train air braking system is of great significance to accurately evaluate its operation state. In order to overcome the influence of sensor fault on the pressure data of train air braking system, it is necessary to design a set of sensor fault-tolerant voting mechanism to ensure that in the case of a pressure sensor fault, the system can accurately identify and locate the position of the faulty sensor, and estimate the fault data according to other normal data. A fault-tolerant mechanism based on multi-classification support vector machine(SVM) and adaptive network-based fuzzy inference system(ANFIS) is introduced. Multi-classification SVM is used to identify and locate the system fault state, and ANFIS is used to estimate the real data of the fault sensor. After estimation, the system will compare the real data of the fault sensor with the ANFIS estimated data. If it is similar,the system will recognize that there is a false alarm and record it. Then the paper tests the whole mechanism based on the real data. The test shows that the system can identify the fault samples and reduce the occurrence of false alarms.

关键词： Support vector machines Fault diagnosis Pressure sensors Fuzzy logic Fault tolerance Adaptive systems Fault tolerant systems

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Amorphous BaTiO_(3) Electron Transport Layer for Thermal Equilibrium-Governed γ-CsPbl_(3) Perovskite Solar Cell with High Power Conversion Efficiency of 19.96%

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Energy & Environmental Materials 2024年第3期7卷 291-302页

作者： Changhyun Lee Chanyong Lee Kyungjin Chae Taemin Kim Seaeun Park Yohan Ko Yongseok Jun Department of Energy Environment Policy and Technology Graduate School of Energy and Environment(KU-KIST Green School)Korea UniversitySeoul 02841Republic of Korea Nano Electronic Materials and Components research center Gumi Electronics and Information Technology Research Institute(GERI)Gumi 39171Republic of Korea Energy Materials research center Clean Energy Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea

Compared to organic-inorganic hybrid perovskites,the cesium-based allinorganic lead halide perovskite(CsPbI_(3))is a promising light absorber for perovskite solar cells owing to its higher resistance to thermal ***,additional research is required to reduce the nonradiative recombination to realize the full potential of CsPbI_(3).Here,the diffusion of Cs ions participating in ion exchange is proposed to be an important factor responsible for the bulk defects inγ-CsPbI_(3)*** based on first-principles density functional theory reveal that the[PbI_(6)]^(4-)octahedral tilt modifies the perovskite crystallographic properties inγ-CsPbI_(3),leading to alterations in its bandgap and crystal *** addition,by substituting amorphous barium titanium oxide(a-BaTiO_(3))for TiO_(2)as the electron transport layer,interfacial defects caused by imperfect energy levels between the electron transport layer and perovskite are ***-resolution transmission electron microscopy and electron energy loss spectroscopy demonstrate that a-BaTiO_(3)forms entirely as a single phase,as opposed to Ba-doped TiO_(2)hybrid nanoclusters or separate domains of TiO_(2)and BaTiO_(3)***,inorganic perovskite solar cells based on the a-BaTiO_(3)electron transport layer achieved a power conversion efficiency of 19.96%.

关键词： amorphous BaTiO_(3) electron transport layer moisture γ-CsPbI_(3)

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Integral precession calibration method of PIGA on linear vibration table

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Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN Shun-qing REN Jun-wei CAO Ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National research center for information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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Quantum dot-enabled infrared hyperspectral imaging with single-pixel detection

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Light(Science & Applications) 2024年第6期13卷 1112-1121页

作者： Heyan Meng Yuan Gao Xuhong Wang Xianye Li Lili Wang Xian Zhao Baoqing Sun School of information Sciences and Engineering Shandong UniversityQingdaoChina center for Optics research and Engineering(CORE) Key Laboratory of Laser&Infrared System(Shandong University)Ministry of EducationShandong UniversityQingdaoChina School of Mechanical Electrical and Information EngineeringShandong UniversityWeihaiChina

Near-infrared(NIR)hyperspectral imaging is a powerful technique that enables the capture of three-dimensional(3D)spectra-spatial information within the NIR spectral range,offering a wide array of ***,the high cost associated with InGaAs focal plane array(FPA)has impeded the widespread adoption of NIR hyperspectral *** this challenge,in this study,we adopt an alternative approach—single-pixel detection for NIR hyperspectral *** investigation reveals that single-pixel detection outperforms conventional FPA,delivering a superior signal-to-noise ratio(SNR)for both spectral and imaging *** implement this strategy,we leverage self-assembled colloidal quantum dots(CQDs)and a digital micromirror device(DMD)for NIR spectral and spatial information multiplexing,complemented by single-pixel detection for simultaneous spectral and image *** experimental results demonstrate successful NIR hyperspectral imaging with a detection window about 600 nm and an average spectral resolution of 8.6 nm with a pixel resolution of 128×*** resulting spectral and spatial data align well with reference instruments,which validates the effectiveness of our *** circumventing the need for expensive and bulky FPA and wavelength selection components,our solution shows promise in advancing affordable and accessible NIR hyperspectral imaging technologies,thereby expanding the range of potential applications.

关键词： spectral Quantum mirror

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A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

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Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui Li Hua Jiang School of Computer and Electronic information Guangxi UniversityNanning530000China Cyber Security and information center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

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Age of information Based User Scheduling and Data Assignment in Multi-User Mobile Edge Computing Networks:An Online Algorithm

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China Communications 2024年第5期21卷 153-165页

作者： Ge Yiyang Xiong Ke Dong Rui Lu Yang Fan Pingyi Qu Gang School of Computer and information Technology Beijing Jiaotong UniversityBeijing 100044China Engineering research center of Network Management Technology for High Speed Railway of Ministry of Education Beijing 100044China Beijing Engineering research center of High-speed Railway Broadband Mobile Communications Beijing 100044China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National research center for information Science and Technology Tsinghua UniversityBeijing 100084China Department of Electrical and Computer Engineering College ParkMarylandUSA

This paper investigates the age of information(AoI)-based multi-user mobile edge computing(MEC)network with partial offloading *** weighted sum AoI(WSA)is first analyzed and derived,and then a WSA minimization problem is formulated by jointly optimizing the user scheduling and data *** to the non-analytic expression of the WSA *** optimization variables and the unknowability of future network information,the problem cannot be solved with known solution ***,an online Joint Partial Offloading and User Scheduling Optimization(JPOUSO)algorithm is proposed by transforming the original problem into a single-slot data assignment subproblem and a single-slot user scheduling sub-problem and solving the two sub-problems *** analyze the computational complexity of the presented JPO-USO algorithm,which is of O(N),with N being the number of *** results show that the proposed JPO-USO algorithm is able to achieve better AoI performance compared with various baseline *** is shown that both the user’s data assignment and the user’s AoI should be jointly taken into account to decrease the system WSA when scheduling users.

关键词： age of information(aoi) mobile edge computing(mec) user scheduling

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