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Few-shot incremental radar target recognition framework based on scattering-topology properties

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Chinese Journal of Aeronautics 2024年第8期37卷 246-260页

作者： Chenxuan LI Weigang zhu Bakun zhu Yonggang LI Graduate School Space Engineering UniversityBeijing 101400China Department of Electronic and Optical Engineering Space Engineering UniversityBeijing 101400China

The continuous emergence of new targets in open scenarios leads to a substantial decrease in the performance of Inverse Synthetic Aperture Radar(ISAR)recognition ***,data scarcity further exacerbates the challenge of identifying new classes of ISAR *** this paper,a few-shot incremental target recognition framework based on Scattering-Topology Properties(STPIL)is ***,STPIL extracts scattering-topology properties of ISAR targets as recognition ***,the pseudo-incremental training strategy effectively alleviates the algorithm’s forgetting of old knowledge,and improves compatibility with new ***,a feature embedding network,with few parameters,is designed based on the graph neural *** embedding network is highly adaptable to changes in data ***,STPIL fully considers the joint distribution and marginal distribution in scattering features,and uses the Brownian distance metric module to make the scattering-topology features more *** results on both the simulation dataset and the public measured data indicate that STPIL can effectively balance new classes with old classes,and has superior performance to other advanced methods in the incremental recognition of targets.

关键词： Brownian distance metric Graph neural networks Incremental learning Inverse Synthetic Aperture Radar(ISAR) Scattering

Stress-strain relationship for reactive powder concrete with recycled powder under uniaxial compression

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1015-1027页

作者： Peng zhu Yunming zhu Wenjun QU Liyu XIE College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China

The recycled powder(RP)from construction wastes can be used to partially replace cement in the preparation of reactive powder *** this paper,reactive powder concrete mixtures with RP partially replacing cement,and natural sand instead of quartz,are *** curing is used,instead of steam curing that is normally requested by standard for reactive powder *** influences of RP replacement ratio(0%,10%,20%,30%),silica fume proportion(10%,15%,20%),and steel fiber proportion(0%,1%,2%)are *** effects of RP,silica fume,and steel fiber proportion on compressive strength,elastic modulus,and relative absorption energy are analyzed,and theoretical models for compressive strength,elastic modulus,and relative absorption energy are established.A constitutive model for the uniaxial compressive stress-strain relationship of reactive powder concrete with RP is *** the increase of RP replacement ratio from 0% to 30%,the compressive strength decreases by 42% and elastic modulus decreases by 24%.

关键词： recycled powder reactive powder concrete elastic modulus relative absorbed energy stress-strain relationship

Preparation of single atom catalysts for high sensitive gas sensing

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International Journal of Extreme Manufacturing 2024年第3期6卷 216-248页

作者： Xinxin He Ping Guo Xuyang An Yuyang Li Jiatai Chen Xingyu Zhang lifeng Wang Mingjin Dai Chaoliang Tan Jia Zhang Key Laboratory of Microsystems and Microstructure Manufacturing Ministry of EducationHarbin Institute of TechnologyHarbin 150080People’s Republic of China Institute for Frontier Materials Deakin UniversityWaurn Ponds CampusLocked Bag 20000Victoria 3220Australia School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Electrical and Electronic Engineering The University of Hong KongPokfulam RoadHong Kong Special Administrative Region of China 999077People’s Republic of China Chongqing Research Institute Harbin Institute of TechnologyChongqing 401120People’s Republic of China

Single atom catalysts(SACs)have garnered significant attention in the field of catalysis over the past decade due to their exceptional atom utilization efficiency and distinct physical and chemical *** the semiconductor-based electrical gas sensor,the core is the catalysis process of target gas molecules on the sensitive *** this context,the SACs offer great potential for highly sensitive and selective gas sensing,however,only some of the bubbles come to the *** facilitate practical applications,we present a comprehensive review of the preparation strategies for SACs,with a focus on overcoming the challenges of aggregation and low *** research efforts have been devoted to investigating the gas sensing mechanism,exploring sensitive materials,optimizing device structures,and refining signal post-processing ***,the challenges and future perspectives on the SACs based gas sensing are presented.

关键词： single atom catalysts preparation sensing mechanism gas sensing

预制上筒-基础杯口嵌入型连接结构受力特性分析

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防灾减灾工程学报 2021年第6期41卷 1271-1278,1294页

作者：李亚程泽坤朱立锋中交第三航务工程勘察设计院有限公司上海200032 上海市政工程设计研究总院(集团)有限公司上海200092 东南大学土木工程学院江苏南京210096

当前装配式结构和工业化建造是土木工程重点发展的方向,预制上筒-基础杯口嵌入型连接结构作为近海土木工程领域典型的装配式结构,具有基础性研究意义。采用刚性理论方法、有限单元法、弹性理论方法对该类型连接结构受力特性进行研究,推... 详细信息

当前装配式结构和工业化建造是土木工程重点发展的方向,预制上筒-基础杯口嵌入型连接结构作为近海土木工程领域典型的装配式结构,具有基础性研究意义。采用刚性理论方法、有限单元法、弹性理论方法对该类型连接结构受力特性进行研究,推导相关理论计算公式,并基于工程计算实例进行对比分析。研究发现,若灌浆粘结可靠、杯口和上筒之间固接时,结构变形较小;若灌浆粘结失效,杯口和上筒之间发生摩擦滑移而产生较大位移,且上筒变位随杯口高度增加而减小,当杯口高度在3.0 m及以上时,变位数值较为合理。相对刚性理论计算公式,基于上筒变形形态、接触摩擦传力方式建立的简化弹性理论公式与有限单元法结果误差较小;其中杯口高度为2.0 m时,平均误差约10%,杯口高度为3.0 m、4.0 m时,平均误差降低为7%、6%左右,结果较为接近;计算结果验证了简化弹性理论公式的合理可行性。

关键词：预制上筒基础杯口连接有限单元法变形形态接触

Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020

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Chinese Geographical Science 2024年第1期34卷 181-194页

作者： zhu Yuanyuan ZHANG Yan zhu Xiaohua Key Laboratory of Geographic Process Analysis&Simulation Hubei Province Central China Normal UniversityWuhan430079China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China

Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important *** study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary *** results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption *** dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality *** the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing *** per capita food carbon emissions of residents in urban and rural showed an overall upward *** total food carbon emissions in urban increased significantly,while that in rural increased first and then *** influence of beef and mutton on carbon emissions is the highest in dietary *** with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern.

关键词： dietary structure structural evolution carbon emission effects carbon neutrality China

Designing hierarchical structures for innovative cooling textile

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Nano Research 2024年第10期17卷 9202-9224页

作者： Xiran Du Jinlei Li Bin zhu Jia zhu National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210023China School of Sustainable Energy and Resources Nanjing UniversitySuzhou 215163China

The potential of personal cooling technologies in reducing air conditioning energy consumption and enhancing human thermal comfort is *** review focuses on recent advancements in hierarchical structure design for innovative cooling *** with insights into fundamental heat transfer processes between the human body,textile,and the surroundings,we uncover key control *** the advanced hierarchical structure designs enabling effective radiation,sweat evaporation,conduction management,and integration of cold energy sources for realizing effective human body cooling are systematically ***,we explore multifunctional designs beyond cooling,including switchable cooling-heating and ***,we engage in discussions on unifying cooling performance tests and additional multiple requirements to make strides toward practical *** review is anticipated to be a valuable resource,providing the scientific and industrial communities with a quick grasp of past advancements,current challenges,and future directions in achieving effective human body cooling.

关键词： thermal comfort personal cooling textile hierarchical structures

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颐和园的露陈座及其纹饰

饰（北京服装学院学报艺术版） 2009年第2期 84-90页

作者：朱利峰中华女子学院

颐和园的露陈座是光绪年间专为慈禧太后举行"万寿节"庆典而添安的大规模露天陈设设施。露陈座的纹饰与造型设计独特,艺术内涵丰富,突出表现了典型的"福、寿、富贵"主题,与颐和园作为皇家园林的园居功能取得了高度的一致,集中体现了统治... 详细信息

颐和园的露陈座是光绪年间专为慈禧太后举行"万寿节"庆典而添安的大规模露天陈设设施。露陈座的纹饰与造型设计独特,艺术内涵丰富,突出表现了典型的"福、寿、富贵"主题,与颐和园作为皇家园林的园居功能取得了高度的一致,集中体现了统治者的审美趣味,艺术价值和历史价值均十分突出。

关键词：颐和园露陈座建筑吉祥纹饰

多孔TiO2层厚度对钙钛矿太阳能电池性能的影响

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化学学报 2015年第3期73卷 261-266页

作者：朱立峰石将建李冬梅孟庆波北京市新能源材料与器件重点实验室中国科学院清洁能源前沿研究实验室中国科学院物理研究所100190

制备了基于不同厚度(100~500nm)多孔TiO2层的钙钛矿太阳能电池,并用SEM、XRD、紫外-可见吸收谱、电压-电流曲线、电化学阻抗谱进行了表征.研究发现,多孔TiO2薄膜厚度对电池性能有很大影响,即随着多孔TiO2薄膜厚度的增加,短路电流略有提... 详细信息

制备了基于不同厚度(100~500nm)多孔TiO2层的钙钛矿太阳能电池,并用SEM、XRD、紫外-可见吸收谱、电压-电流曲线、电化学阻抗谱进行了表征.研究发现,多孔TiO2薄膜厚度对电池性能有很大影响,即随着多孔TiO2薄膜厚度的增加,短路电流略有提高,而开路电压和填充因子呈下降趋势;但同时,较厚的多孔TiO2薄膜可有效减弱滞回现象.进一步采用电化学阻抗谱和暗态电流-电压曲线研究了载流子复合.电化学阻抗谱表明,膜厚增加会增大载流子复合但不会改变二极管理想因子.通过拟合暗态电流-电压曲线得到反向饱和电流,随着膜厚增加,反向饱和电流会增大,从而加剧了载流子复合.通过优化多孔TiO2薄膜厚度,基于150nm多孔TiO2薄膜钙钛矿电池的认证效率达到15.56%.

关键词：钙钛矿太阳能电池载流子复合二氧化钛膜厚度

Old Pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China

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Journal of Forestry Research 2024年第5期35卷 155-170页

作者： Wenxin Li Liangjun zhu Lianhua zhu Mengdan Jing Censhi Qian Yu zhu Paolo Cherubini College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British Columbia2004-2424 Main MallVancouverBC V6T 1Z4Canada

Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental *** the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree *** this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern *** normalized log basal area increment of trees in both age groups increased significantly following rapid warming in *** in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth *** growth was more strongly influenced by temperature than by moisture,particularly in old *** tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young *** forests had a significantly lower resistance to extreme drought but faster recovery compared to young ***“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat *** ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter *** findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon Peak&Carbon Neutrality”goals in China.

关键词： Tree rings Pinus massoniana Age effects Drought resilience Subtropical forests Rapid warming