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Effect of artificial natural light on the development of myopia among primary school-age children in China:a three-year longitudinal study

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 924-931页

作者： Hui-Min Cai Meng-Yan Li Yi Cao Yu-Lin Wu Ming Liang Yu-Shi Chen bi-kun Xian Yu-Juan Huang Xiang-bin Kong Department of Ophthalmology the Second People’s Hospital of FoshanAffiliated Foshan Hospital of Southern Medical UniversityFoshan 528000Guangdong ProvinceChina Guangdong Medical University Zhanjiang 524023Guangdong ProvinceChina Guangdong Cosio Lighting Corporation Foshan 528000Guangdong ProvinceChina

AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age ***:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this *** whole randomization method was adopted to include classes as a group according to 1:1 randomized *** in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural *** students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus ***-year follow-up,the students underwent same *** was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuity<20/***:There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±*** three-year cumulative incidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%CI,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%CI,0.08 to 0.28 D);P<0.001].Elongation of axial length was significantly different between in the control group(0.77 mm)and the intervention group[0.72 mm;difference of 0.05 mm(95%CI,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.

关键词： myopia artificial natural light school-age children efficacy

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基于物联网技术的智能电力抄核系统设计与实现

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科技创新与生产力 2024年第5期45卷 142-144页

作者：毕坤王斌国网宁夏电力有限公司银川供电公司宁夏银川750400

为解决电力抄表核算信息更新速度慢、人工抄核误差大的问题,设计基于物联网技术的智能电力抄核系统。此系统数据采集层由电能计量装置,采集用户电能计量信息数据后,汇入集中器;集中器将所采集的电能计量数据,通过数据传输层的GPRS网络与... 详细信息

为解决电力抄表核算信息更新速度慢、人工抄核误差大的问题,设计基于物联网技术的智能电力抄核系统。此系统数据采集层由电能计量装置,采集用户电能计量信息数据后,汇入集中器;集中器将所采集的电能计量数据,通过数据传输层的GPRS网络与ZigBee网络协调器连接,由ZigBee网络协调器将电能计量数据的抄核信息,有效发送至数据管理层的主站计算机;主站计算机使用基于Kettle的无损增量信息智能更新模型,将智能抄表数据进行自动更新后,由核算账务管理模型完成费用核算。实验结果显示此系统可实现高精度、高效率电力抄核问题的智能化管理。

关键词：物联网技术智能电力抄核系统设计

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基于多模态数据感知的低压配电网台区故障区段精准定位

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电子设计工程 2024年第17期32卷 122-126页

作者：吴迪李强毕坤龙丹程时润国网鄂州供电公司湖北鄂州436000

为了提升低压配电网台区故障区段精准定位效果,该文提出基于多模态数据感知的低压配电网台区故障区段精准定位方法。该方法运用主成分分析法确定多模态暂态零序电流数据的综合指标,并采集相关数据。通过相似性指标提取特征参数,并利用... 详细信息

为了提升低压配电网台区故障区段精准定位效果,该文提出基于多模态数据感知的低压配电网台区故障区段精准定位方法。该方法运用主成分分析法确定多模态暂态零序电流数据的综合指标,并采集相关数据。通过相似性指标提取特征参数,并利用循环神经网络自适应融合各监测点的数据。计算监测点间暂态零序电流的相关系数,并与预设阈值比较,以判定故障区段。实验结果表明,该方法能有效感知并融合多模态数据,且在不同故障角下均能准确地定位故障区段。

关键词：多模态数据感知低压配电网故障区段精准定位主成分分析相关系数

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A novel domain decomposition-based model for efficient dynamic predictions of large composite machine tools

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Science China(Technological Sciences) 2024年第6期67卷 1765-1782页

作者： YU YangBo JI Yu Lei CHEN YanRen XU kun bi QingZhen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

We propose a large combined moving component composed of carbon fiber reinforced polymer(CFRP)laminates for making lightweight machine tools with high dynamic *** accurate dynamic prediction of composite machine tools is essential for the new generation machine *** paper aims to address two challenges in numerical dynamic modeling and the design of composite machine tools to enhance development efficiency.(1)Anisotropic composite laminates,which form the composite machine tool,exhibit coupling in various *** propose the generalized continuity condition of the boundary to tackle this dynamic modeling challenge.(2)Composite machine tools feature numerous composite-metal coupled *** mechanical model correction of isotropic metals is performed to address their *** take the example of a five-axis gantry machine tool with composite moving parts,establish a dynamic model for efficient prediction,and verify it through simulation and *** proposed method yields remarkable results,with an average relative error of only 3.85%in modal frequency prediction and a staggering 99.7%reduction in solution time compared to finite element *** further discuss the dynamic performance of the machine tool under varied stacking angles and layer numbers of the composite machine *** propose general design criteria for composite machine tools to consider the modal frequency and manufacturing cost of machine tools.

关键词： machine tool dynamics carbon fiber reinforced polymer composite laminates

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A modified 3D mean strain energy density criterion for predicting shale mixed-mode I/III fracture toughness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2411-2428页

作者： kun Zheng Chaolin Wang Yu Zhao Jing bi Haifeng Liu College of Civil Engineering Guizhou UniversityGuiyang550025China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic *** edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi *** theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture *** distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is *** the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is *** results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar *** macroscopic fracture signatures are consistent with those of triaxial hydraulic *** average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than *** to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.

关键词： Longmaxi shale Hydraulic fracturing Fracture mechanisms Fracture criteria Mixed-mode I/III fracture toughness Edge-notched disk bending

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Correlation of karst agricultural geo-environment with non-karst agricultural geo-environment with respect to nutritive elements in Guizhou

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Chinese Journal Of Geochemistry 2011年第4期30卷 563-568页

作者： CHEN Rong bi kun Miner College of Guizhou University Guiyang 550004 China Guizhou Bureau of Geology and Mineral Exploration ＆ Development Guiyang 550003 China

The karst area accounts for 61.9% of the total area in Guizhou Province, which gives rise to a fragile environment and backward economy. Comparative studies on the element contents of rock and soil and agriculture production in both carbonate area and non-carbonate area have been made to establish factors leading to low output and poor quality of agricultural products in the karst area. The result shows that there is an apparent lack of nutrient elements in carbonate rocks. The trace element contents of carbonate rocks are only 3532.27×10-6, but those of non-carbonate rocks are 10894.21×10-6. The available element contents in culti-vated soil delivered from carbonate rocks are merely 101.4×10-6, but those from non-carbonate rocks are 326.05×10-6. The available element contents and total element contents in cultivated soil delivered from non-carbonate rocks are 3 times higher than those from carbonate rocks. Besides, high-quality agricultural products such as rice, potato and tea are mainly produced in the non-carbonate area. It is indicated that the low output and quality of agricultural products are caused by the above-mentioned low trace element contents and poor agricultural environment. Therefore, a new method of mineral nutrients compensation has been put forward, which is very effective to raise the load-bearing capacity of agricultural environment, agricultural output and quality of agricultural products.

关键词：岩溶地区地质环境营养元素农业生产贵州省微量元素含量碳酸盐岩区农产品质量

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Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： Wen-Jun Cai Jian-Guo Jiang Zi-Dong Zhang Zi-Xuan Liu Lu-JieZhang Zhen-kun Long Ke bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)

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Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： bi Rui GAN Shu YUAN Xiping LI kun LI Raobo LUO Weidong CHEN Cheng GAO Sha HU Lin ZHU Zhifu School of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China Plication Engineering Research Center of Spatial Information Surveying and Mapping Technology in Plateau and Mountainous Areas Set by Universities in Yunnan Province Kunming 650093China West Yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,Yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features

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后基督教时代的巴赫诠释——论汉斯·布鲁门伯格的《马太受难曲》

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中国音乐学 2022年第3期3卷 140-144页

作者：毕琨柏林洪堡大学音乐学系

德国哲学家汉斯·布鲁门伯格的专著《马太受难曲》反思了巴赫的同名音乐作品,它为后基督教时代中生命个体的感性体验予以理论性的支持。这部专著隐含着19世纪早期浪漫派的美学、20世纪的音乐史学以及恩斯特·布洛赫的音乐哲学的影响。... 详细信息

德国哲学家汉斯·布鲁门伯格的专著《马太受难曲》反思了巴赫的同名音乐作品,它为后基督教时代中生命个体的感性体验予以理论性的支持。这部专著隐含着19世纪早期浪漫派的美学、20世纪的音乐史学以及恩斯特·布洛赫的音乐哲学的影响。布鲁门伯格认为,处于后基督教时代的人们能够打破陈旧的神学教条的束缚,对现代性的听众而言那逝去的神性并不会影响对《马太受难曲》的接受,相反,在新的现代性视域之中,听众可以收获一种更为纯粹的音乐性体验。

关键词：布鲁门伯格《马太受难曲》视域绝对音乐意义

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On the Proper Holomorphic Mappings between Equidimensional Hartogs Domains over Hermitian Symmetric Manifolds

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1215-1228页

作者： En Chao bi School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we study a family of Hartogs domains fibred over Hermitian symmetric manifolds being a unit ball in C^(m).The aim of the present study is to establish the rigidity results about proper holomorphic mappings between two equidimensional Hartogs domains over Hermitian symmetric *** particular,we can fully determine its biholomorphic equivalence and automorphism group.

关键词： Proper holomorphic mapping Hartogs domains Hermitian symmetric manifolds

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