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Superior efficiency and stability of YbO-enhanced perovskite solar cells

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Science China Materials 2024年

作者： qifeng zhang Guozhong Cao Department of Materials Science and Engineering University of Washington Department of Electrical and Computer Engineering North Dakota State University

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Semi-supervised remote sensing image scene classification with prototype-based consistency

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Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang LI zhang LI Zi WANG Kun WANG qifeng YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale datasets.However,annotating the remote sensing images is time-consuming and even tough for experts.Deep neural networks trained using a few labeled samples usually generalize less to new unseen images.In this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled images.To this end,we,first,propose a feature enhancement module to extract discriminative features.This is achieved by focusing the model on the foreground areas.Then,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature representations.We conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning

Robust multi-sensor image matching based on normalized self-similarity region descriptor

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Chinese Journal of Aeronautics 2024年第1期37卷 271-286页

作者： Xuecong LIU Xichao TENG Jing LUO zhang LI qifeng YU Yijie BIAN College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China High-Tech Institute Qingzhou 262500China

Multi-modal image matching is crucial in aerospace applications because it can fully exploit the complementary and valuable information contained in the amount and diversity of remote sensing images.However,it remains a challenging task due to significant non-linear radiometric,geometric differences,and noise across different sensors.To improve the performance of heterologous image matching,this paper proposes a normalized self-similarity region descriptor to extract consistent structural information.We first construct the pointwise self-similarity region descriptor based on the Euclidean distance between adjacent image blocks to reflect the structural properties of multi-modal images.Then,a linear normalization approach is used to form Modality Independent Region Descriptor(MIRD),which can effectively distinguish structural features such as points,lines,corners,and flat between multi-modal images.To further improve the matching accuracy,the included angle cosine similarity metric is adopted to exploit the directional vector information of multi-dimensional feature descriptors.The experimental results show that the proposed MIRD has better matching accuracy and robustness for various multi-modal image matching than the state-of-the-art methods.MIRD can effectively extract consistent geometric structure features and suppress the influence of SAR speckle noise using non-local neighboring image blocks operation,effectively applied to various multi-modal image matching.

关键词： Remote sensing Multi-modal image matching Template matching Feature descriptor Similarity metric Synthetic Aperture Radar(SAR)

The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE qifeng DONG Yunpeng CAI Yuanfeng ZHAI Mingguo XIAO Aifang zhang Hong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 10029China

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock series.The samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of Eu.In the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_N,10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type granite.Combined the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization fractional.The values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement rocks.The comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

Hybrid Hierarchical Particle Swarm Optimization with Evolutionary Artificial Bee Colony Algorithm for Task Scheduling in Cloud Computing

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Computers, Materials & Continua 2024年第1期78卷 1135-1156页

作者： Shasha Zhao Huanwen Yan qifeng Lin Xiangnan Feng He Chen Dengyin zhang College of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Jiangsu Key Laboratory of Broadband Wireless Communication and Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Tongding Interconnection Information Co. Ltd.Suzhou215000China

Task scheduling plays a key role in effectively managing and allocating computing resources to meet various computing tasks in a cloud computing environment.Short execution time and low load imbalance may be the challenges for some algorithms in resource scheduling scenarios.In this work,the Hierarchical Particle Swarm Optimization-Evolutionary Artificial Bee Colony Algorithm(HPSO-EABC)has been proposed,which hybrids our presented Evolutionary Artificial Bee Colony(EABC),and Hierarchical Particle Swarm Optimization(HPSO)algorithm.The HPSO-EABC algorithm incorporates both the advantages of the HPSO and the EABC algorithm.Comprehensive testing including evaluations of algorithm convergence speed,resource execution time,load balancing,and operational costs has been done.The results indicate that the EABC algorithm exhibits greater parallelism compared to the Artificial Bee Colony algorithm.Compared with the Particle Swarm Optimization algorithm,the HPSO algorithmnot only improves the global search capability but also effectively mitigates getting stuck in local optima.As a result,the hybrid HPSO-EABC algorithm demonstrates significant improvements in terms of stability and convergence speed.Moreover,it exhibits enhanced resource scheduling performance in both homogeneous and heterogeneous environments,effectively reducing execution time and cost,which also is verified by the ablation experimental.

关键词： Cloud computing distributed processing evolutionary artificial bee colony algorithm hierarchical particle swarm optimization load balancing

Revealing the key role of non-solvating diluents for fast-charging and low temperature Li-ion batteries

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Journal of Energy Chemistry 2024年第7期94卷 171-180页

作者： Yuping zhang Siyin Li Junkai Shi Jiawei Lai Ziyue Zhuang Jingwen Liu Wenming Yang Liang Ma Yue-Peng Cai Jjian Xu qifeng Zheng School of Chemistry Guangzhou Key Laboratory of Materials for Energy Conversion and StorageSouth China Normal UniversityGuangzhou 510006GuangdongChina Guangzhou Foreign Language School Guangzhou 511455GuangdongChina Department of ChemistryCity University of Hong KongHong Kong 999077China

Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based elec-trolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetoni-trile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Lit sol-vates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphitellNCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.

关键词： Li-ion battery Fast-charging Low temperature Non-solvating diluent Shielding effect

Understanding the role of tungsten on Pt/CeO_(2)for vinyl chloride catalytic combustion

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Journal of Rare Earths 2022年第9期40卷 1462-1470,I0005页

作者： qifeng zhang Zhengbo Zhou Tian Fang Han Gu Yanglong Guo Wangcheng Zhan Yun Guo Li Wang Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis School of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Spherical CeO_(2)synthesized by the hydrothermal process was used as support to prepare Pt/WO_(3)/CeO_(2),and the effects of tungsten(W)contents on activity,stability and polychlorinated by-products were investigated to understand the role of W for vinyl chloride(VC)catalytic oxidation.The introduction of12 wt%W to Pt/CeO_(2)(P12 WC)exhibits the highest catalytic activity with 90%conversion of VC at 250℃,meanwhile the stability improves and the polychlorinated by-products in the tail gas significantly decrease due to the removal of dissociated Cl species in the formation of HCl.The beneficial effects of W on Pt/CeO_(2)are closely related to the chemical state of Pt,redox and surface acid sites distribution.The doped W not only makes Pt disperse evenly on the support with the high valence,but also weakens the interaction between Pt and CeO_(2)by the formation of Pt-O-W and Pt-O-W-O-Ce species,which facilitates oxygen mobility.In addition,the modification of W species also significantly increases the surface acidity amount and changes the distribution of acid sites.

关键词： Tungsten oxides Vinyl chloride Catalytic oxidation Pt/CeO_(2) By-products Rare earths

Linearly Compact Difference Scheme for the Two-Dimensional Kuramoto-Tsuzuki Equation with the Neumann Boundary Condition

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Annals of Applied Mathematics 2023年第1期39卷 49-78页

作者： qifeng zhang Lu zhang Department of Mathematics Zhejiang Sci-Tech UniversityHangzhouZhejiang 310018China School of Mathematics and Statistics Xuzhou University of TechnologyXuzhouJiangsu 221018China

In this paper,we analyze and test a high-order compact difference scheme numerically for solving a two-dimensional nonlinear Kuramoto-Tsuzuki equation under the Neumann boundary condition.A three-level average technique is utilized,thereby leading to a linearized difference scheme.The main work lies in the pointwise error estimate in H^(2)-norm.The optimal fourth-order convergence order is proved in combination of induction,the energy method and the embedded inequality.Moreover,we establish the stability of the difference scheme with respect to the initial value under very mild condition,however,does not require any step ratio restriction.Extensive numerical examples with/without exact solutions under diverse cases are implemented to validate the theoretical results.

关键词： Kuramoto-Tsuzuki equation compact difference scheme pointwise error estimate stability numerical simulation

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基于多曝光图像序列的相机响应函数标定方法

光学学报 2024年第4期44卷 128-135页

作者：高刘正关棒磊苏昂李璋于起峰国防科技大学空天科学学院湖南长沙410072 酒泉卫星发射中心甘肃酒泉735000

基于多项式拟合的标定方法可在缺乏相机曝光时间的条件下,获取相机响应函数(CRF)曲线和图像曝光比,具备广泛的适用性。然而该方法存在迭代发散和标定精度不高问题,影响其实际应用。本文通过分析传统多项式拟合标定方法流程,发现在全局... 详细信息

基于多项式拟合的标定方法可在缺乏相机曝光时间的条件下,获取相机响应函数(CRF)曲线和图像曝光比,具备广泛的适用性。然而该方法存在迭代发散和标定精度不高问题,影响其实际应用。本文通过分析传统多项式拟合标定方法流程,发现在全局误差函数条件下,标定数据集合中存在大量无效项,既减少了有效标定数据,又降低了图像曝光比迭代计算精度。针对这一问题,提出了一种改进的联合局部误差函数标定方法,可在两幅曝光相近的图像间选取标定数据,避免引入无效项,使得计算多项式系数和曝光比的数据一致。在公开数据集和某工业相机拍摄数据集上的标定结果表明,改进方法具有较好的收敛性,相比于传统方法,颜色三通道CRF曲线分布更加紧凑,通道间曝光比平均偏差分别减少了49.83%和42.25%。

关键词：成像系统相机响应函数多曝光图像拟合多项式