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Ultra-lightweight CNN design based on neural architecture search and knowledge distillation: A novel method to build the automatic recognition model of space target ISAR images

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Defence Technology（防务技术） 2022年第6期18卷 1073-1095页

作者： Hong Yang Ya-sheng Zhang Can-bin yin Wen-zhe ding Space Engineering University Beijing101416China Beijing Institute of Tracking and Telecommunications Technology China

In this paper,a novel method of ultra-lightweight convolution neural network(CNN)design based on neural architecture search(NAS)and knowledge distillation(KD)is *** can realize the automatic construction of the space target inverse synthetic aperture radar(ISAR)image recognition model with ultra-lightweight and high *** method introduces the NAS method into the radar image recognition for the first time,which solves the time-consuming and labor-consuming problems in the artificial design of the space target ISAR image automatic recognition model(STIIARM).On this basis,the NAS model’s knowledge is transferred to the student model with lower computational complexity by the flow of the solution procedure(FSP)distillation ***,the decline of recognition accuracy caused by the direct compression of model structural parameters can be effectively avoided,and the ultralightweight STIIARM can be *** the method,the Inverted Linear Bottleneck(ILB)and Inverted Residual Block(IRB)are firstly taken as each block’s basic structure in *** the expansion ratio,output filter size,number of IRBs,and convolution kernel size are set as the search parameters to construct a hierarchical decomposition search ***,the recognition accuracy and computational complexity are taken as the objective function and constraint conditions,respectively,and the global optimization model of the CNN architecture search is ***,the simulated annealing(SA)algorithm is used as the search strategy to search out the lightweight and high accuracy STIIARM *** that,based on the three principles of similar block structure,the same corresponding channel number,and the minimum computational complexity,the more lightweight student model is designed,and the FSP matrix pairing between the NAS model and student model is ***,by minimizing the loss between the FSP matrix pairs of the NAS model and student model,the student model’s weight adjust

关键词： Space target ISAR image Neural architecture search Knowledge distillation Lightweight model

Effect of Marangoni Number on Thermocapillary Convection and Free-Surface Deformation in Liquid Bridges

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Journal of Thermal Science 2016年第2期25卷 178-187页

作者： ZHANG yin HUANG Hu-Lin ZHOU Xiao-Ming ZHU gui-Ping ZOU Yong College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Institute of Engineering Thermophysics Chinese Academy of Sciences

Floating zone technique is a crucible-free process for growth of high quality single crystals. Unstable thermocapillary convection is a typical phenomenon during the process under microgravity. Therefore, it is very important to investigate the instability of thermocapillary convection in liquid bridges with deformable free-surface under microgravity. In this works, the Volume of Fluid(VOF) method is employed to track the free-surface movement. The results are presented as the behavior of flow structure and temperature distribution of the molten zone. The impact of Marangoni number(Ma) is also investigated on free-surface deformation as well as the instability of thermocapillary convection. The free-surface exhibits a noticeable axisymmetric(but it is non-centrosymmetric) and elliptical shape along the circumferential direction. This specific surface shape presents a typical narrow ‘neck-shaped' structure with convex at two ends of the zone and concave at the mid-plane along the axial direction. At both θ = 0° and θ = 90°, the deformation ratio ξ increases rapidly with Ma at first, and then increases slowly. Moreover, the hydrothermal wave number m and the instability of thermocapillary convection increase with Ma.

关键词： thermocapillary convection microgravity Floating zone deformable free-surface VOF liquid bridge

Characterization of the unprecedented polynya events north of Greenland in 2017/2018 using remote sensing and reanalysis data

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Acta Oceanologica Sinica 2020年第9期39卷 5-17页

作者： Ruibo Lei Dawei gui Zhouli Yuan Xiaoping Pang ding Tao Mengxi Zhai MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430072China

Based on an ice concentration threshold of 90%,it has been identified that two polynya events occurred in the region north of Greenland during the 2017/2018 ice *** winter event lasted from February 20 to March 3,2018 and the summer event persisted from August 2 to September 5,*** minimum ice concentration derived from Advanced Microwave Scanning Radiometer 2(AMSR2)observations was 72%and 65%during the winter and summer events,*** occurrence of both events can be related to strengthened southerly winds associated with an increased east-west zonal surface level air pressure gradient across the north Greenland due to perturbation of mid-troposphere polar *** relatively warm air temperature during the 2017/2018 freezing season in comparison with previous years,together with the occurrence of the winter polynya,formed favourable pre-conditions for ice field fracturing in summer,which promoted the formation of the summer *** southerly winds and increased cover of new ice over the open water were the dominant factors for the disappearance of the winter polynya,whereas increased ice inflow from the north was the primary factor behind the closure of the summer ***-1 Synthetic Aperture Radar(SAR)images were found better suited than AMSR2 observations for quantification of a new ice product during the polynya event because the SAR images have high potential for mapping of different sea ice regimes with finely spatial *** unprecedented polynya events north of Greenland in 2017/2018 are important from the perspective of Arctic sea ice loss because they occurred in a region that could potentially be the last“Arctic sea ice refuge”in future summers.

关键词： sea ice ice concentration ice motion polynya Greenland Arctic Ocean

Multidimensional measurement of poverty and its spatio-temporal dynamics in China from the perspective of development geography

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Journal of Geographical Sciences 2021年第1期31卷 130-148页

作者： DONG yin JIN gui DENG Xiangzheng WU Feng School of Public Administration China University of GeosciencesWuhan 430074China School of Economics and Management China University of GeosciencesWuhan 430074China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

Exploring the spatio-temporal dynamics of poverty is important for research on sustainable poverty reduction in China. Based on the perspective of development geography, this paper proposes a panel vector autoregressive(PVAR) model that combines the human development approach with the global indicator framework for Sustainable Development Goals(SDGs) to identify the poverty-causing and the poverty-reducing factors in China. The aim is to measure the multidimensional poverty index(MPI) of China’s provinces from 2007 to 2017, and use the exploratory spatio-temporal data analysis(ESTDA) method to reveal the characteristics of the spatio-temporal dynamics of multidimensional poverty. The results show the following:(1) The poverty-causing factors in China include the high social gross dependency ratio and crop-to-disaster ratio, and the poverty-reducing factors include the high per capita GDP, per capita social security expenditure, per capita public health expenditure, number of hospitals per 10,000 people, rate of participation in the new rural cooperative medical scheme, vegetation coverage, per capita education expenditure, number of universities, per capita research and development(R&D) expenditure, and funding per capita for cultural undertakings.(2) From 2007 to 2017, provincial income poverty(IP), health poverty(HP), cultural poverty(CP), and multidimensional poverty have been significantly reduced in China, and the overall national poverty has dropped by 5.67% annually. there is a differentiation in poverty along different dimensions in certain provinces.(3) During the study period, the local spatial pattern of multidimensional poverty between provinces showed strong spatial dynamics, and a trend of increase from the eastern to the central and western regions was noted. The MPI among provinces exhibited a strong spatial dependence over time to form a pattern of decrease from northwestern and northeastern China to the surrounding areas.(4) The spatio-temporal net

关键词： development geography multidimensional poverty poverty measurement spatio-temporal dynamics collaborative poverty reduction

Construction of three stereocenters via hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones

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Science China Chemistry 2021年第2期64卷 232-237页

作者： Yi-Xuan ding Zhou-Hao Zhu Han Wang Chang-Bin Yu Yong-gui Zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A Ru-catalyzed hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones was developed for construction of three stereocenters including two coherent and discontiguous chiral centers and a chiral quaternary carbon with excellent enantio-and *** synthesis of four stereoisomers could be conducted with high *** desymmetrization could be achieved at gram scale without loss of reactivity and optical purity,and a formal synthesis of bioactive molecule(-)-isocelorbicol was completed.

关键词： desymmetrization hydrogenation 1,3-cyclohexanediones three stereocenters chiral quaternary carbon

北美冬青‘奥斯特’花芽分化期内含物质变化特征

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东北林业大学学报 2025年第1期53卷 49-56页

作者：侯召斌殷雅文杨丁郝明灼邹义萍南京警察学院南京210023 南京林业大学南京国图信息产业有限公司

通过石蜡切片结合物候观察,将北美冬青(Ilex vericillata)花芽分化过程分为花芽分化初期(P1)、花序原基分化期(P2)、花萼原基分化期(P3)、花瓣原基分化期(P4)、雌雄蕊原基分化期(P5)5个阶段。测定枝条内源激素质量分数及比值(赤霉素(GA... 详细信息

通过石蜡切片结合物候观察,将北美冬青(Ilex vericillata)花芽分化过程分为花芽分化初期(P1)、花序原基分化期(P2)、花萼原基分化期(P3)、花瓣原基分化期(P4)、雌雄蕊原基分化期(P5)5个阶段。测定枝条内源激素质量分数及比值(赤霉素(GA_3)、脱落酸(ABA)、玉米素核苷(ZR)、吲哚乙酸(IAA)、(w(IAA)+w(ZR))/w(ABA)、(w(IAA)+w(ZR))/w(GA_3)、w(GA_3)/w(ABA))、枝条矿物质(碳、氮、钾、磷)质量分数及比值(碳氮质量分数比)、可溶性糖、可溶性蛋白质量分数的变化。结果表明:碳、钾、氮和磷、内源激素质量分数、可溶性糖、可溶性蛋白质量分数均随发育阶段变化而表现显著变化。玉米素核苷质量分数在花萼原基分化期(P3)达到最大值,脱落酸质量分数在花瓣原基分化期(P4)最大,吲哚乙酸及赤霉素质量分数在雌雄蕊原基分化期(P5)达到最大值。(w(IAA)+w(ZR))/w(GA_(3))在花萼原基分化期(P3)达到峰值,(w(IAA)+w(ZR))/w(ABA)、w(GA_3)/w(ABA)在雌雄蕊原基分化期(P5)最高。氮、磷、钾质量分数都于花萼原基分化期(P3)达到最高,碳质量分数及碳氮质量分数比在雌雄蕊原基分化期(P5)达到巅峰。可溶性糖、可溶性蛋白质量分数变化都呈类似的上升趋势。分析雌雄蕊原基分化期(P5)枝条内含物质与开花、结实量之间的相关性,结合主成分分析结果显示,可溶性糖、可溶性蛋白质量分数,玉米素核苷、吲哚乙酸、脱落酸质量分数,(w(IAA)+w(ZR))/w(GA_3)、(w(IAA)+w(ZR))/w(ABA),与北美冬青开花、结实量呈正相关,全磷质量分数与开花量呈显著负相关,内源激素、可溶性糖、可溶性蛋白质量分数与开花量、结实量有较强的相关性。较高水平的激素及可溶性糖、可溶性蛋白是保证开花、结实量较为理想的条件。

关键词：北美冬青内源激素花芽分化主成分分析

Human mirror neuron system and its plasticity

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Neural Regeneration Research 2008年第3期3卷 321-323页

作者： Wei Chen Tifei Yuan yin Wang Jun ding Institute of Cognition and Behavioral Neuroscience Hangzhou Normal University Hangzhou 310018 Zhejiang Province China Department of Psychology Hangzhou Normal University Hangzhou 310018 Zhejiang Province China Department of Anatomy Li Kai Shing Faculty of Medicine The University of Hong Kong Hong Kong School of Life Sciences Shanghai University Shanghai 200436 China

The mirror neuron system （MNS） was first discovered in non-human primates; these neurons fire when a monkey performs an action or observes another monkey （or even some people） performing that same action. Recent findings have suggested that neural rehabilitation might be achieved through the activation of the MNS in patients after stroke. We propose two major mechanisms （one involving adult neurogenesis and another involving brain-derived neurotrophic factor） that may underlie the activation, modulation and experience-dependent plasticity in the MNS, for further study on promoting central nerve functional reconstruction and rehabilitation of patients with central nervous system injury.

关键词： mirror neuron system adult neurogenesis neural plasticity rehabilitation spinal cord injury

Recognition of sick pig cough sounds based on convolutional neural network in field situations

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Information Processing in Agriculture 2021年第3期8卷 369-379页

作者： Yanling yin ding Tu Weizheng Shen Jun Bao College of Electrical and Information Northeast Agricultural UniversityHarbinPR China Tus College of Digit Guangxi University of Science and TechnologyLiuZhouPR China College of Animal Science and Technology Northeast Agricultural UniversityHarbinPR China Key Laboratory of Swine Facilities Engineering Ministry of AgricultureNortheast Agricultural UniversityHarbinPR China

Coughing is an obvious respiratory disease symptom,which affects the airways and lungs of *** pig houses,continuous online monitoring of cough sounds can be used to build an intelligent alarm system for disease early *** to complicated interferences in piggery,recognition of pig cough sound becomes *** a lot of algorithms have been proposed to recognize the pig cough sounds,the recognition accuracy in field sit-uations still needs *** purpose of this research is to provide a highly accu-rate pig cough recognition method for the respiratory disease alarm *** propose a classification algorithm based on the fine-tuned AlexNet model and feature of the *** the advantages of the convolutional neural network in image recognition,the sound signals are converted into spectrogram images for recognition,to enhance the *** compare the proposed algorithm’s performance with the probabilistic neural net-work classifier and some existing *** results reveal that the proposed algorithm significantly outperforms the other algorithms-cough and overall recognition accuracies reach to 96.8%and 95.4%,respectively,with 96.2%F1-score achieved.

关键词： Convolutional neural network Cough recognition Respiratory diseases detection Sound classification

A disk-corona model for the low/hard state of black hole X-ray binaries

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Research in Astronomy and Astrophysics 2013年第10期13卷 1163-1180页

作者： Jiu-Zhou Wang ding-Xiong Wang Chang-yin Huang School of Physics Huazhong University of Science and Technology

A disk-corona model for fitting the low/hard（LH）state of the associated steady jet in black hole X-ray binaries（BHXBs）is proposed based on the large-scale magnetic field configuration that arises from the coexistence of the Blandford-Znajek（BZ）and Blandford-Payne（BP）processes,where the magnetic field configuration for the BP process is determined by the requirement of energy conversion from Poynting energy flux into kinetic energy flux in the *** is found that corona current is crucial to guarantee the consistency of the jet launching from the accretion *** relative importance of the BZ and BP processes in powering jets from black hole accretion disks is discussed,and the LH state of several BHXBs is fitted based on our *** addition,we suggest that magnetic field configuration can be regarded as the second parameter for governing the state transition of BHXBs.

关键词： accretion accretion disks black hole physics magnetic field jet power