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中国百年乡土教材演变述评

广西民族大学学报（哲学社会科学版） 2008年第1期30卷 49-55页

作者：李素梅滕星中央民族大学教育学院北京100081 中央民族大学教育学院及民族教育研究所北京100081

依据大量散见的史料,进行系统的梳理分析,将中国百年乡土教材的发端、演变脉络总结为三个时期五次高峰期,认为中国乡土教材源于舶来成于传统;伴随于乡土教育运动;适应于教育改革运动,普及面广而作用为补充;存在着有发展空间无实施保证... 详细信息

依据大量散见的史料,进行系统的梳理分析,将中国百年乡土教材的发端、演变脉络总结为三个时期五次高峰期,认为中国乡土教材源于舶来成于传统;伴随于乡土教育运动;适应于教育改革运动,普及面广而作用为补充;存在着有发展空间无实施保证、体系上与学校教育的其他内容相对脱节、其功能作用或被夸大或被忽视、缺乏相应的师资、相应理论建设不够、一直没有得到有效总结等局限。

关键词：乡土教材百年演变述评

Tunnel silicon nitride manipulated reconfigurable bi-mode nociceptor analog

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Photonics Research 2024年第8期12卷 1820-1827页

作者： CHENGDONG YANG YILONG liU liNliN su XINWEI li liHUA XU QImei CHENG Jiangsu Province Engineering Research Center of Integrated Circuit Reliability Technology and Testing System Wuxi UniversityWuxi 214105China

Neuromorphic applications have shown great promise not only for efficient parallel computing mode to hold certain computational tasks,such as perception and recognition,but also as key biomimetic elements for th intelligent sensory system of next-generation ***,achieving such a biomimetic nociceptor tha can adaptively switch operation mode with a stimulation threshold remains a *** rational design of material properties and device structures,we realized an easily-fabricated,low-energy,and reconfigurable no *** is capable of threshold-triggered adaptive bi-mode jump that resembles the biological alarm system With a tunnel silicon nitride(Si_(3)N_(4))we mimicked the intensity-and rehearsal-triggered jump by means of th tunneling mode transition of Si_(3)N_(4)*** threshold signals the device can also express some common synaptic functions with an extremely low energy density of 33.5 f J∕μm^(2).In addition,through the modulation o Si_(3)N_(4)thickness it is relatively easy to fabricate the device with differing pain *** nociceptor analog based on a tunneling layer provides an opportunity for the analog pain alarm system and opens up a new path toward threshold-related novel applications.

关键词： Tunnel tunneling rational

Increase of chiral sensing ability in host-guest chemistry by magnetic anisotropy

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Science China Chemistry 2024年第8期67卷 2775-2782页

作者： Jia-liang Chen Bin li Feng Yang Tiesheng Shi Xun-Cheng su State Key Laboratory of Elemento-organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Chemical Engineering and Materials ScienceZaozhuang UniversityZaozhuang 277160China

Enantiomeric molecules generally play distinct functions in chemistry,biology,and *** physical and chemical properties of chiral analytes lay difficulty in discrimination and quantification of the *** report herein an efficient approach of increasing the chiral sensing ability ofβ-cyclodextrin(β-CD),a widely used host molecule,in the hostguest chemistry by magnetic anisotropy.A rigid and chiral lanthanide binding tag was attached to theβ-CD to amplify the changes of nuclear magnetic resonance(NMR)signals in the host-guest recognition *** installation of the paramagnetic lanthanide ion inβ-CD greatly enhances the enantiomeric discrimination up to 30-fold in comparison with the diamagneticβ-CD *** addition,the magnitude of the paramagnetic effects is tunable according to the diverse range of paramagnetic strength of the lanthanide *** reported method significantly increases the chiral sensing ability ofβ-CD,which can be applied to other host *** transferred paramagnetic effects,pseudocontact shifts(PCSs)and paramagnetic relaxation enhancements(PREs),from the host to the guest molecules,are valuable structural restraints to determine the absolute stereochemistry of the chiral *** strategy does not need modification of the analytes and is complementary to the reported analytical methods that rely on the functionalization of the chiral analytes.

关键词： chiral recognition nuclear magnetic resonance host-guest chemistry magnetic anisotropy lanthanide ions

Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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Science China(Technological Sciences) 2024年第1期67卷 172-182页

作者： ZHANG RuiXian HAN YiNing su Man liN ZeFeng li HaoWei ZHANG liXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Management Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous *** tackle this problem,a robust Lyapunov value function(rLVF)is *** rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed *** the rLVF,a uniformly ultimate boundedness criterion is *** criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be ***,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is *** train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is *** proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,*** experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

Comparative study on the hydrogen storage performance of as-milled MgRENi rapid quenched alloy catalyzed by metal sulfides

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Journal of Magnesium and Alloys 2024年第5期12卷 2010-2023页

作者： Xiaoping Dong Zhaoqing Zhang liying Yang Shenghai Xin Dandan su Zhiyuan li Department of Mechanical Design and Manufacture and Automation Hebei UniversityBaoding 071000PR China Baoding New Energy Vehicle Power Engineering Technology Research Center Hebei UniversityBaoding 071002PR China Hebei Technology Innovation Center for lightweight of New Energy Vehicle Power System(Preparation) Hebei UniversityBaoding 071002PR China

The composites of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy and 3 wt.%M(M=CoS,CoS_(2),MoS_(2))catalyst were prepared by high-speed vibration ball *** effects of metal sulfides on the hydrogenation and dehydrogenation dynamics of alloys were *** results show that the as-milled composites contain a large number of amorphous embedded by a small amount of nanocrystals,and there are many point *** ball milling,the crystal grain size in the composites containing CoS is relatively larger,followed by CoS_(2)and MoS_(2)*** hydrogenation,the amorphous phase is crystallized to form Mg_(2)NiH_(4),YH_(3),Pr_(8)H_(18.96),Sm_(3)H_7,Mg,Co or Mo phases,however,Mg_(2)Ni,YH_(2),PrH_(2)and Ni_(3)Y phases appeared after *** maximum hydrogenation capacity of the composites containing CoS,CoS_(2)and MoS_(2)are 3.939,4.265 and 4.507 wt.%,*** hydrogenation saturation ratio of composite containing MoS_(2)is higher than that of the composites containing CoS and CoS_(2).The dehydrogenation activation energy of the composites containing CoS,CoS_(2)and MoS_(2)is 107.76,68.43 and 63.28 ***^(-1).H_(2).On the improvement of hydrogen storage performance of Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)alloy,the catalytic effect of MoS_(2)sulfide is better than that of CoS_(2)sulfide,and which is better than CoS sulfide.

关键词： Mg_(20)Pr_(1)Sm_(3)Y_(1)Ni_(10)as-quenched alloy CoS CoS_(2)and MoS_(2)sulfide Milling Activation energy Hydrogen storage dynamics

3D hand pose and shape estimation from monocular RGB via efficient 2D cues

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Computational Visual Media 2024年第1期10卷 79-96页

作者： Fenghao Zhang lin Zhao Shengling li Wanjuan su liman liu Wenbing Tao Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis&Treatment School of Biomedical EngineeringSouth Central Minzu UniversityWuhan430074China National Key Laboratory of Science and Technology of Multi-spectral Information Processing School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan430074China

Estimating 3D hand shape from a single-view RGB image is important for many ***,the diversity of hand shapes and postures,depth ambiguity,and occlusion may result in pose errors and noisy hand *** full use of 2D cues such as 2D pose can effectively improve the quality of 3D human hand shape *** this paper,we use 2D joint heatmaps to obtain spatial details for robust pose *** also introduce a depth-independent 2D mesh to avoid depth ambiguity in mesh regression for efficient hand-image *** method has four cascaded stages:2D cue extraction,pose feature encoding,initial reconstruction,and reconstruction ***,we first encode the image to determine semantic features during 2D cue extraction;this is also used to predict hand joints and for ***,during the pose feature encoding stage,we use a hand joints encoder to learn spatial information from the joint ***,a coarse 3D hand mesh and 2D mesh are obtained in the initial reconstruction step;a mesh squeeze-and-excitation block is used to fuse different hand features to enhance perception of 3D hand ***,a global mesh refinement stage learns non-local relations between vertices of the hand mesh from the predicted 2D mesh,to predict an offset hand mesh to fine-tune the reconstruction *** and qualitative results on the FreiHAND benchmark dataset demonstrate that our approach achieves state-of-the-art performance.

关键词： hand 3D reconstruction deep learning image features 3D mesh

Plasma characteristics and material erosion mechanism in multi-channel wire electrical discharge machining

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Chinese Journal of Aeronautics 2024年第10期37卷 508-525页

作者： Guokang su Chuanyun ZHANG Junfei li Xiaolei CHEN Guixian liU Yongjun ZHANG State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of Advanced Manufacturing Technology of Marine Energy Equipment Guangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Nontraditional Machining Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China School of Mechanical Engineering Xi’an Technological UniversityXi’an 710021China

Multi-channel wire electrical discharge machining(MC-WEDM)is an advanced and high-efficiency machining technology,but its material erosion mechanism remains *** this study,dual-channel wire electrical discharge machining was utilized as a case study to investigate the impact of the plunging current on both the plasma characteristics and material erosion under complex discharge *** analysis was conducted on the charged particles in the plasma,revealing that the plunging current can influence the trajectory of the plasma by modifying the selfmagnetic *** particle tracking method was employed to simulate the motion of electrons,revealing that in MC-WEDM,electrons exhibited a larger and more uniform *** evolution of the plasma within a single-pulse discharge was observed using high-speed photography technology,and the discharge signals collected from different channels were *** was observed that the plasma in MC-WEDM experienced more intense back-and-forth sweeping on the workpiece surface,facilitating the ejection of molten metal from the molten *** oscillating plasma exhibits a larger processing area and a more uniform distribution of energy,resulting in the formation of larger and shallower discharge ***,the influence of the amplitude and time point of the plunging current on the volume and area of the discharge craters was ***,MC-WEDM significantly reduced the occurrence of holes and micro-cracks and exhibited a thinner recast layer in the continuous discharge experiment.

关键词： Multi-channel WEDM Discharge observation Plunging current Plasma characteristics Material erosion Discharge crater

Vegetation changes across the Eocene-Oligocene transition:Global signals *** development

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Science China Earth Sciences 2024年第9期67卷 2937-2952页

作者： Mengxiao WU Lutz KUNZMANN Shufeng li Vasilis TEODORIDIS Zhekun ZHOU Tao su CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Senckenberg Natural History Collections Dresden Konigsbrücker LandstraBe 159Dresden 01109Germany Department of Biology and Environmental Studies Faculty of EducationCharles UniversityMagdalény Rettigové411639 Prague 1Czech Republic State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China

The Eocene-Oligocene transition(EOT)marked a rapid global cooling event,often considered as the beginning of the modern icehouse *** by various factors,including tectonic activity and paleogeographic settings,the terrestrial records indicate a diverse response of fauna and vegetation to this global *** examined nine macrofossil assemblages from seven fossil localities on the southeastern margin of the Tibetan Plateau and from the mid-latitudinal Europe ranging from the latest Bartonian and Priabonian(37.71-33.9 Ma)to the Rupelian(33.9-27.82 Ma).Our aims were to trace and compare the vegetation history of both regions in the late Eocene and early *** results show that both regions experienced changes in vegetation composition in response to climate change,characterized by a decrease in the percentages of broad-leaved evergreen elements and distinctive changes in general vegetation types.A general change in the overall vegetation type from subtropical broad-leaved evergreen forests in the late Eocene to temperate broad-leaved mixed deciduous evergreen forests,or mixed mesophytic forests,in the early Oligocene is recognized in both *** results indicate a clear change in leaf architecture,leaf margin states,and secondary venation types in the mid-latitudinal Europe,while the results from the southeastern margin of the Tibetan Plateau show a distinct reduction in leaf *** data suggest that both global and regional factors played key roles in shaping the vegetation in the two regions.

关键词： Eocene-Oligocene transition Plant fossil Paleoclimate Leaf architecture Biodiversity

Temporal and Spatial Trends in HIV Positivity Rate for VCT Clinics—China,2015–2022

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China CDC weekly 2024年第1期6卷 6-11页

作者： Yi liu Rong su Dongmin li Shaorong Wang Mengjie Han National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina

Introduction:Human immunodeficiency virus(HIV)voluntary counseling and testing(VCT)clinics play a critical role in identifying and diagnosing HIV *** study aimed to describe the trend of HIV positivity rate(HPR)among Chinese VCT clinics between 2015 and ***:This study utilized data from the China Information System for Disease Control and Prevention to analyze the trend in the HPR for VCT clinics from 2015 to *** HPR was calculated by dividing the number of newly-reported HIV cases by the number of HIV tests,multiplied by 100%.To identify temporal and spatial trends in the HPR,we employed joinpoint regression analysis and the Getis-Ord hotspot ***:From 2015 to 2022,VCT clinics in China performed a total of 22,075,386 HIV tests,leading to the identification of 260,353 HIV cases,resulting in a HPR of 1.18%.The HPR consistently declined over the study period,with an average annual percent change(AAPC)of−7.5%(95%confidence interval:−12.6%,−2.2%,Plinics in China have played a significant role in identifying HIV *** declining HPR observed in these clinics may indicates the progress has been made in some degree in mitigating HIV among high-risk ***,it is crucial to further improving the utilization of VCT clinics for HIV testing.

关键词： VCT dividing Spatial