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Chinese Journal of Aeronautics 2018年第1期31卷 31-40页

作者： yuchen SONG Datong LIU Yandong HOU Jinxiang yu yu peng Department of Automatic Test and Control School of Electrical Engineering and Automation Harbin Institute of Technology

Lithium-ion batteries have become the third-generation space batteries and are widely utilized in a series of spacecraft. Remaining Useful Life （RUL） estimation is essential to a spacecraft as the battery is a critical part and determines the lifetime and reliability. The Relevance Vector Machine （RVM） is a data-driven algorithm used to estimate a battery＇s RUL due to its sparse feature and uncertainty management capability. Especially, some of the regressive cases indicate that the RVM can obtain a better short-term prediction performance rather than long-term prediction. As a nonlinear kernel learning algorithm, the coefficient matrix and relevance vectors are fixed once the RVM training is conducted. Moreover, the RVM can be simply influenced by the noise with the training data. Thus, this work proposes an iterative updated approach to improve the long-term prediction performance for a battery＇s RUL prediction. Firstly, when a new estimator is output by the RVM, the Kalman filter is applied to optimize this estimator with a physical degradation model. Then, this optimized estimator is added into the training set as an on-line sample, the RVM model is re-trained, and the coefficient matrix and relevance vectors can be dynamically adjusted to make next iterative prediction. Experimental results with a commercial battery test data set and a satellite battery data set both indicate that the proposed method can achieve a better performance for RUL estimation.

关键词： Iterative updating Kalman filter Lithium-ion battery Relevance vector machine Remaining useful life estimation

Matching CCD images to a stellar catalog using locality-sensitive hashing

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Research in Astronomy and Astrophysics 2018年第2期18卷 105-114页

作者： Bo Liu Jia-Zong yu Qing-yu peng College of Information Science and Technology Jinan University Sino-French Joint Laboratory for Astrometry Dynamics and Space Science Jinan University

The usage of a subset of observed stars in a CCD image to find their corresponding matched stars in a stellar catalog is an important issue in astronomical research. Subgraph isomorphic-based algorithms are the most widely used methods in star catalog matching. When more subgraph features are provided, the CCD images are recognized better. However, when the navigation feature database is large, the method requires more time to match the observing model. To solve this problem, this study investigates further and improves subgraph isomorphic matching algorithms. We present an algorithm based on a locality-sensitive hashing technique, which allocates quadrilateral models in the navigation feature database into different hash buckets and reduces the search range to the bucket in which the observed quadrilateral model is located. Experimental results indicate the effectivity of our method.

关键词： astronomical databases: miscellaneous -- methods: data analysis -- techniques: imageprocessing

Spatial distribution and influencing factors of settlements in the farming-pastoral ecotone of Inner Mongolia,China

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Ecosystem Health and Sustainability 2020年第1期6卷 558-565,557页

作者： yu peng Qinghui Wang College of Life and Environmental Sciences Minzu University of ChinaBeijingChina Urban Planning&Design Institute of Xiong’an RongchengChina

Rural settlements serve as an important part of the rural landscape,and environmental conditions influence their spatial *** hypothesize that there are variations in the spatial patterns of settlements across different farming–pastoral ecotones that exist in accordance with different human activities and environmental *** used remote sensing imagery,digital elevation model,and GIS technology to analyze and compare the spatial patterns of settlements and factors influencing these patterns across pastoral,agricultural,and ecotone areas in Inner Mongolia,China.A Voronoi model,adjacency analysis,landscape metrics,and quantitative analysis were *** results indicated that(1)the settlements in the three areas tended to have a random spatial distribution,and although there were no significant differences between the settlement types,agricultural settlements tended to be clustered and pastoral settlements tended to be evenly distributed;(2)the pastoral area had only a few large and sparsely fragmented patches;(3)the factors influencing settlement distribution mainly differed with respect to the NDVI,distance to roads and rivers,and elevation across three areas,but the slope degree was *** results indicated there are no significant differences between the spatial patterns of settlements along the agricultural to pastoral gradient,although environmental conditions ***,we can optimize the spatial pattern of settlements and achieve sustainable development within farming–pastoral ecotones.

关键词： Farming–pastoral ecotone settlement spatial characteristic influence factor

Inversion of UEP signatures induced by ships based on PSO method

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Defence Technology（防务技术） 2020年第1期16卷 172-177页

作者： yu peng Jin-fang Cheng Run-xiang Jiang Military Key Laboratory for Military Target Characteristics Naval University of EngineeringWuhan 430033PR China College of Weaponry Engineering Naval University of EngineeringWuhan 430033PR China

To model the underwater electric potential(UEP) of ships,a multiple point-electrodes method is commonly ***,it is difficult to determine the total number of point-electrodes,their respective positions and current *** this paper,the particle swarm optimization(PSO) method is applied to solve the number,positions and current values of these point-electrodes according to the UEP distribution at a known depth below the keel of a ship.A scaled ship model experiment is carried out to determine the effectiveness of the *** results show that for hulls in a latural corrosion or cathodic protection state,the UEP inversion accuracy can reach 85% at different depths below the *** method is suitable for software implementation and can help the simulation and prediction of UEP signatures.

关键词： UEP PSO Inversion Point-electrode

Shape Discrimination Analysis of Rolled Strip Based on Strip Element Method

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Journal of Iron and Steel Research International 2004年第1期11卷 29-32页

作者： peng Yan CHU yu-peng LIU Hong-min Yanshan University

Based on load-oriented manufacturing control theory, different combining modes and slab storage calculation method for continuous casting and hot rolling were discussed. The buffer capacity index of continuous casting-rolling was introduced, and the reasonable slab storage under different combining modes was calculated with buffer capacity index of 120.00 h for CCR, 79.20 h for HCR, 19.68 h for DHCR and 3.84 h for DR. Thin slab is 1.20 h, and the strip is zero. Theory gist was provided for steel enterprise to decrease storage.

关键词： continuous casting hot rolling production control slab storage

A New Noise-Tolerant Dual-Neural-Network Scheme for Robust Kinematic Control of Robotic Arms With Unknown Models

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IEEE/CAA Journal of Automatica Sinica 2022年第10期9卷 1778-1791页

作者： Ning Tan peng yu Zhiyan Zhong Fenglei Ni IEEE the School of Computer Science and Engineering&Key Laboratory of Machine Intelligence and Advanced Computing Ministry of EducationSun Yat-sen UniversityGuangzhou 510006China the School of Automation Guangdong Polytechnic Normal UniversityGuangzhou 510665China the State Key Laboratory of Robotics and Systems Harbin Institute of Technology(HIT)Harbin 150080China

Taking advantage of their inherent dexterity,robotic arms are competent in completing many tasks *** a result of the modeling complexity and kinematic uncertainty of robotic arms,model-free control paradigm has been proposed and investigated ***,robust model-free control of robotic arms in the presence of noise interference remains a problem worth *** this paper,we first propose a new kind of zeroing neural network(ZNN),i.e.,integration-enhanced noise-tolerant ZNN(IENT-ZNN)with integration-enhanced noisetolerant ***,a unified dual IENT-ZNN scheme based on the proposed IENT-ZNN is presented for the kinematic control problem of both rigid-link and continuum robotic arms,which improves the performance of robotic arms with the disturbance of noise,without knowing the structural parameters of the robotic *** finite-time convergence and robustness of the proposed control scheme are proven by theoretical ***,simulation studies and experimental demonstrations verify that the proposed control scheme is feasible in the kinematic control of different robotic arms and can achieve better results in terms of accuracy and robustness.

关键词： Dual zeroing neural networks(ZNN) finite-time convergence model-free robot control robustness analysis

Early-season crop type mapping using 30-m reference time series

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Journal of Integrative Agriculture 2020年第7期19卷 1897-1911页

作者： HAO peng-yu TANG Hua-jun CHEN Zhong-xin MENG Qing-yan KANG yu-peng Key Laboratory of Agricultural Remote Sensing Minstry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agrcultural SciencesBejing 100081P.R China Shenzhen Key Laboratory for Geo-Environmental Monitoring of Coastal Zone of the National Administration of Surveying Mapping and Geo-Information&Shenzhen Key Laboratory of Spatial Smart Sensing and ServicesShenzhen UniversityShenzhen 518060P.R.China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBejjing 100101P.R.China

Early-season crop type mapping could provide important information for crop growth monitoring and yield prediction,but the lack of ground-surveyed training samples is the main challenge for crop type *** reference time series based method(RBM)has been proposed to identify crop types without the use of ground-surveyed training samples,the methods are not suitable for study regions with small field size because the reference time series are mainly generated using data set with low spatial *** the combination of Landsat data and Sentinel-2 data could increase the temporal resolution of 30-m image time series,we improved the RBM by generating reference normalized difference vegetation index(NDVI)/enhanced vegetation index(EVI)time series at 30-m resolution(30-m RBM)using both Landsat and Sentinel-2 data,then tried to estimate the potential of the reference NDVI/EVI time series for crop identification at early *** a test case,we tried to use the 30-m RBM to identify major crop types in Hengshui,China at early season of 2018,the results showed that when the time series of the entire growing season were used for classification,overall classification accuracies of the 30-m RBM were higher than 95%,which were similar to the accuracies acquired using the ground-surveyed training *** addition,cotton,spring maize and summer maize distribution could be accurately generated 8,6 and 8 weeks before their harvest using the 30-m RBM;but winter wheat can only be accurately identified around the harvest time ***,NDVI outperformed EVI for crop type classification as NDVI had better separability for distinguishing crops at the green-up time *** with the previous RBM,advantage of 30-m RBM is that the method could use the samples of the small fields to generate reference time series and process image time series with missing value for early-season crop casification;while,samples collected from multiple years should be futher

关键词： early season Landsat Sentinel-2 reference time series crop classification Hengshui

High-Safety Anode Materials for Advanced Lithium-Ion Batteries

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Energy & Environmental Materials 2024年第5期7卷 1-19页

作者： Kai yuan yu Lin Xiang Li yufeng Ding peng yu Jian peng Jiazhao Wang HuaKun Liu Shixue Dou Wuhan Institute of Marine Electric Propulsion Wuhan 430000China State Key Laboratory of Material Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation CampusSquires WayNorth WollongongNew South Wales 2522Australia Institute of Energy Materials Science(IEMS) University of Shanghai for Science and TechnologyShanghai 200093China

Lithium-ion batteries(LIBs)play a pivotal role in today's society,with widespread applications in portable electronics,electric vehicles,and smart *** LIBs predominantly utilize graphite anodes due to their high energy density and *** anodes face challenges,however,in extreme safety-demanding situations,such as airplanes and passenger *** lithiation of graphite can potentially form lithium dendrites at low temperatures,causing short ***,the dissolution of the solid-electrolyte-interphase on graphite surfaces at high temperatures can lead to intense reactions with the electrolyte,initiating thermal *** review introduces two promising high-safety anode materials,Li_(4)Ti_(5)O_(12)and TiNb_(2)O_(7).Both materials exhibit low tendencies towards lithium dendrite formation and have high onset temperatures for reactions with the electrolyte,resulting in reduced heat generation and significantly lower probabilities of thermal ***_(4)Ti_(5)O_(12)and TiNb_(2)O_(7)offer enhanced safety characteristics compared to graphite,making them suitable for applications with stringent safety *** review provides a comprehensive overview of Li_(4)Ti_(5)O_(12)and TiNb_(2)O_(7),focusing on their material properties and practical *** aims to contribute to the understanding and development of high-safety anode materials for advanced LIBs,addressing the challenges and opportunities associated with their implementation in real-world applications.

关键词： anodes electrode materials lithium-ion batteries thermal runaway

Estimations of Bounds on the Multiplicative Fractional Integral Inequalities Having Exponential Kernels

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Communications in Mathematics and Statistics 2024年第2期12卷 187-211页

作者： yu peng Hao Fu Tingsong Du Department of Mathematics College of ScienceChina Three Gorges UniversityYichang 443002People’s Republic of China Three Gorges Mathematical Research Center China Three Gorges UniversityYichang 443002People’s Republic of China

To investigate the fractional Hermite–Hadamard-type inequalities,a class of the multiplicative fractional integrals having exponential kernels is *** estimations of upper bounds for the newly introduced class of integral operators are obtained in terms of the established∗differentiable *** our results presented in this study are substantial generalizations of previousﬁndings given by Ali et al.(Asian Res J Math 12:1–11,2019).Three examples are also provided to identify the correctness of the results that occur with the change of the parameter α.

关键词： Hermite–Hadamard-type inequalities Multiplicative fractional integrals Multiplicatively convex functions Differentiable functions

Pigment signatures of some diatoms isolated from China seas

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Acta Oceanologica Sinica 2006年第1期25卷 108-118页

作者： YAO peng yu Zhigang DENG Chunmei College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China

The photosynthetic pigments of 12 species （14 strains） of cultured diatoms from six genera under specific conditions were examined by the HPLC. The diatom genera were Skeletonema, Thalassiosira, Chaetoceros, Nitzschla, Phaeodactylum and Meuniera. All strains were isolated from China seas and most of them were from the Jiaozhou Bay, China. Fifteen pigments were identified and eight of them were various chlorophyll a derivatives. Chlorophyll a, c2 and c1 and the carotenoids fucoxanthin, diadinoxanthin, diatoxanthin and β, β-carotene existed in all species. The ratios of each pigment to chlorophyll a were compared with the results in literatures. The pigment ratios of this study generally fall within the ranges reported by the literatures although the maximum ratio of fucoxanthin to chlorophyll a was higher and the ratios of chlorophyll c and diatoxanthin to chlorophyll a were low. The pigment ratios are useful to understanding the pigment signatures of diatoms in the Jiaozhou Bay, China, and to setting up the chemotaxonomic method of phytoplankton in these sea areas.

关键词： diatoms pigment HPLC ratio Jiaozhou Bay