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Joint alignment and steering to manage interference

Digital Communications and Networks 2024年第2期10卷 429-438页

作者： Zhao Li Xiujuan Liang Yinghou Liu Jia Liu Zheng yan School of Cyber Engineering Xidian UniversityXi'an710126China Technol.on Commun.Net.Lab. The 54th Research Inst.of China Elec.Technol.Group Corp.Shijiazhuang050081China School of Computer Science and Technology Xidian UniversityXi'an710126China The Department of Communications and Networking(Comnet) Aalto University02150EspooFinland

In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network ***,when managing multiple disturbances from the same source,it may not be feasible to use existing IM methods such as Interference Alignment(IA)and Interference Steering(IS)*** is because with IA,the aligned interference becomes indistinguishable at its desired Receiver(Rx)under the cost constraint of Degrees-of-Freedom(DoF),while with IS,more transmit power will be consumed in the direct and repeated application of IS to each *** remedy these deficiencies,Interference Alignment Steering(IAS)is proposed by incorporating IA and IS and exploiting their advantages in *** IAS,the interfering Transmitter(Tx)first aligns one interference incurred by the transmission of one data stream to a one-dimensional subspace orthogonal to the desired transmission at the interfered Rx,and then the remaining interferences are treated as a whole and steered to the same subspace as the aligned ***,two improved versions of IAS,i.e.,IAS with Full Adjustment at the Interfering Tx(IAS-FAIT)and Interference Steering and Alignment(ISA),are *** former considers the influence of IA on the interfering user-pair's *** orthogonality between the desired signals at the interfered Rx can be maintained by adjusting the spatial characteristics of all interferences and the aligned interference components,thus ensuring the Spectral Efficiency(se)of the interfering communication *** ISA,the power cost for IS at the interfered Tx is minimized,hence improving se performance of the interfered *** the proposed methods are realized at the interfering and interfered Txs cooperatively,the expenses of IM are shared by both *** in-depth simulation results show that joint use of IA and

关键词： Interference Interference management Interference alignment Interference steering Spectral efficiency

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Ghost-YOLO v8:An Attention-Guided Enhanced Small Target Detection Algorithm for Floating Litter on Water Surfaces

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Computers, Materials & Continua 2024年第9期80卷 3713-3731页

作者： Zhongmin Huangfu Shuqing Li Luoheng yan School of Information Engineering North China University ofWater Resources and Electric PowerZhengzhou450046China

Addressing the challenges in detecting surface floating litter in artificial lakes,including complex environments,uneven illumination,and susceptibility to noise andweather,this paper proposes an efficient and lightweight Ghost-YOLO(You Only Look Once)v8 *** algorithmintegrates advanced attention mechanisms and a smalltarget detection head to significantly enhance detection performance and ***,an se(Squeeze-and-Excitation)mechanism is incorporated into the backbone network to fortify the extraction of resilient features and precise target *** mechanism models feature channel dependencies,enabling adaptive adjustment of channel importance,thereby improving recognition of floating litter ***,a 160×160 small-target detection layer is designed in the feature fusion neck to mitigate semantic information loss due to varying target *** design enhances the fusion of deep and shallow semantic information,improving small target feature representation and enabling better capture and identification of tiny floating ***,to balance performance and efficiency,the GhostConv module replaces part of the conventional convolutions in the feature fusion ***,a novel C2fGhost(CSPDarknet53 to 2-Stage Feature Pyramid Networks Ghost)module is introduced to further reduce network ***,to address the challenge of occlusion,a newloss function,WIoU(Wise Intersection over Union)v3 incorporating a flexible and non-monotonic concentration approach,is adopted to improve detection rates for surface floating *** outcomes of the experiments demonstrate that the Ghost-YOLO v8 model proposed in this paper performs well in the dataset Marine,significantly enhances precision and recall by 3.3 and 7.6 percentage points,respectively,in contrast with the base model,mAP@0.5 and mAP 0.5:0.95 improve by 5.3 and 4.4 percentage points and reduces the computational volume by 1.88MB,the FPS value hardly decreases

关键词： YOLO v8 surface floating litter target detection attention mechanism small target detection head ghostnet loss function

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Two different autorefractors for vision screening in children and adolescents

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 331-338页

作者： Xiao-Jun Chen Lin-Jie Liu Bing Sun Dan-Dan Jiang Shu-Shu Zuo yan-Hui Wang Chun-Hua Zhang yan-yan Chen School of Optometry and Ophthalmology Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To compare the consistency of two autorefractors(Tianle RM-9000 and Topcon KR-800)for school-age myopia children,and to provide a basis for largescale data analysis and ***:The refractive error in 909 subjects(age 4–18y)were measured using both autorefractors without *** data were analyzed using Fourier decomposition and the correlation coefficients,intraclass correlation coefficients(ICC),and Bland-Altman limits of agreement(LoA)for each parameter were ***:There was a strong correlation between the spherical equivalent(se),sphere diopter(DS),and cylinder diopter(DC)readings of the Tianle RM-9000 and those of the Topcon KR-800,with correlation coefficient values of 0.98,0.98 and 0.83 and ICC values of 0.99,0.99 and 0.93,***,the correlation coefficients and ICC values of J0 and J45 were unreliable(R=-0.004,-0.034;both ICCse,DS,and DC measured by the Tianle RM-9000 were significantly biased toward myopia compared with the Topcon KR-800,and the mean differences were-0.072,-0.026,-0.091 D,respectively(all Pse,DS,and DC was 0.63 D,0.50 D,0.62 D,respectively;all these values were in the clinically acceptable *** J0 and J45,the mean differences were close to zero(P=0.43,0.84);however,the 95%LoA were relatively wide(J0 SD:0.53;95%CI:-1.00,1.10;J45 SD:0.52;95%CI:-1.00,1.00).CONCLUSION:The two autorefractors are consistent with each other,as the differences in se,DS,and DC were within the clinically acceptable *** can compare the data measured by either device in different studies and use the two devices in the same study to generate a dataset that can be analyzed ***,the J0 and J45 vectors are unreliable and should not be used to assess astigmatism.

关键词： refractive error autorefractors school-age myopia children

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The abundance,distribution,and enrichment mechanism of harmful trace elements in coals from Guizhou,Southwestern China

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Acta Geochimica 2024年第5期43卷 889-903页

作者： Hui Hou Wei Cheng Ruidong yang yan Zhang College of Mining Guizhou UniversityGuiyangChina National and Local Joint Laboratory of Engineering for Effective Utilization of RegionalMineral Resources from Karst Areas GuiyangChina Guizhou Key Laboratory of Comprehensive Utilization of Non-Metallic Mineral Resources GuiyangChina College of Resource and Environment Engineering Guizhou UniversityGuiyangChina

Coal seams can enrich a variety of harmful trace elements under specific geological *** spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are *** harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human *** is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace *** on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of *** results show that the average contents of Cd,Pb,se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei *** enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical *** supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou.

关键词： Harmful trace elements Distribution characteristics Enrichment law Geological and geochemical features Guizhou

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Influence of rare earth oxides on microstructure and mechanical properties of nickel-based superalloys fabricated by high energy beam processing:A review

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Journal of Rare Earths 2024年第9期42卷 1629-1645,I0001页

作者： Lianjie Bi Hua yan Peilei Zhang Haichuan Shi Zhiyuan Li Ruidi Li School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai201620China College of Agricultural Science and Engineering Hohai UniversityNanjing211100China Department of Mechanics and Maritime Science Chalmers University of TechnologyGothenburSE41296Sweden State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

In this paper,the effects of rare earth oxides on the micro structure and mechanical properties of nickelbased superalloys prepared by high-energy beam processing technology were critically *** focus is on the optimal amount of rare earth oxides that can produce ideal *** attention was paid to their main strengthening mechanisms,including solid solution strengthening mainly in the form of solid solution dissolved in the nickel-based alloy and improving the microstructure of the alloy by grain refinement or fine grain strengthening produced by homogenizing the distribution phase.Y_(2)O_(3),La_(2)O_(3) and CeO_(2) rare earth oxides can also improve the fluidity of the alloy molten pool and reduce the segregation of alloying *** advantages can significantly improve the mechanical properties of the ***,this paper outlines the future research directions of rare earth oxides,aiming to expand their application potential.

关键词： Rare earths High energy beam Nickel-based superalloys Microstructure Mechanical properties

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Controlled Twill Surface Structure Endowing Nanofiber Composite Membrane Excellent Electromagnetic Interference Shielding

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Nano-Micro Letters 2024年第11期16卷 255-273页

作者： Dechang Tao Xin Wen Chenguang yang Kun yan Zhiyao Li Wenwen Wang Dong Wang Key Laboratory of Textile Fiber and Products(Wuhan Textile University) Ministry of EducationWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry Chemical Engineering and BiotechnologyDonghua UniversityShanghai 201620People’s Republic of China

Inspired by the Chinese Knotting weave structure,an electromagnetic interference(EMI)nanofiber composite membrane with a twill surface was ***(vinyl alcohol-co-ethylene)(Pva-co-PE)nanofibers and twill nylon fabric were used as the matrix and filter templates,respectively.A Pva-co-PEMXene/silver nanowire(Pva-co-PE-MXene/AgNW,PM_(x)Ag)membrane was successfully prepared using a template *** the MXene/AgNW content was only 7.4 wt%(PM_(7.4)Ag),the EMI shielding efficiency(se)of the composite membrane with the oblique twill structure on the surface was 103.9 dB and the surface twill structure improved the EMI by 38.5%.This result was attributed to the pre-interference of the oblique twill structure in the direction of the incident EM wave,which enhanced the probability of the electromagnetic waves randomly colliding with the MXene ***,the internal reflection and ohmic and resonance losses were *** PM_(7.4)Ag membrane with the twill structure exhibited both an outstanding tensile strength of 22.8 MPa and EMI se/t of 3925.2 dB cm^(-1).Moreover,the PM_(x)Ag nanocomposite membranes demonstrated an excellent thermal management performance,hydrophobicity,non-flammability,and performance stability,which was demonstrated by an EMI se of 97.3%in a high-temperature environment of 140℃.The successful preparation of surface-twill composite membranes makes it difficult to achieve both a low filler content and a high EMI se in electromagnetic shielding *** strategy provides a new approach for preparing thin membranes with excellent EMI properties.

关键词： Twill surface structure MXene/AgNW Nanofiber membrane Electromagnetic interference Flexibility and mechanical properties

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Modulating redox transition kinetics by anion regulation in Ni-Fe-X(X=O,S,se,N,and P)electrocatalyst for efficient water oxidation

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Nano Research 2024年第6期17卷 4720-4728页

作者： Liting Wei Kaini Zhang Rui Zhao Lei Zhang yan Zhang Suyi yang Jinzhan Su International Research Center for Renewable Energy&State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Applied Chemistry Yuncheng UniversityYuncheng 044000China

NiFe-based electrocatalysts will experience dynamical surface reconstruction during oxygen evolution reaction(OER)process,and the derived metal(oxy)hydroxide hybrids on the surface have been considered as the actual active species for *** efforts have been dedicated to understanding the surface reconstruction,but there is rare research on recognizing the origin of improved performance derived from anion species of ***,the OER electrocatalytic characteristics were tuned with different anions in NiFe-based catalyst,using NiFe-based oxides/nitride/sulfide/selenides/phosphides(NiFeX,X=O,N,S,se,and P)as the model *** combination of X-ray photoelectronic spectroscopy,electrochemical tests,operando spectroscopic characterizations,and density functional theory(DFT)calculations,reveals that anion with lower electronegativity in NiFe-based catalyst leads to higher conductivity and delayed valence transition of Ni sites,as well as optimized adsorption behavior towards oxygen intermediates,contributing to enhanced OER ***,NiFeP electrocatalyst demonstrates an ultralow overpotential of 265 mV at 20 mA·cm−2 for OER,as well as long-term *** work not only offers further insights into the effect of anionic electronegativity on the intrinsic OER electrocatalytic properties of NiFe-based electrocatalyst but also provides guide to design efficient non-noble metal-based electrocatalysts for water oxidation.

关键词： oxygen evolution reaction(OER) anion species electronegativity valence transition

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中国宏观层面全要素生产率测算及国际比较

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经济管理学刊 2023年第2期2卷 1-26页

作者：王鹏郭凯明颜色中国人民银行金融研究所中山大学岭南学院北京大学光华管理学院

本文测算了1997—2021年中国宏观层面全要素生产率(简称TFP)的增长率和贡献率,并与美国进行了比较分析。分析发现,中国TFP的增长率和贡献率在2007年前呈单边上升趋势,此后呈V形走势;受2008年国际金融危机和2019年新冠疫情的影响,2010、2... 详细信息

本文测算了1997—2021年中国宏观层面全要素生产率(简称TFP)的增长率和贡献率,并与美国进行了比较分析。分析发现,中国TFP的增长率和贡献率在2007年前呈单边上升趋势,此后呈V形走势;受2008年国际金融危机和2019年新冠疫情的影响,2010、2011和2020年TFP增长率处于低点;2012年后TFP的贡献率恢复明显,2015年后已普遍高于2006年前。中国TFP增长率普遍高于美国,但危机后中美差距有所缩小;美国TFP贡献率在危机前基本高于中国,但危机后,特别是2012年以来中国在大多数年份都已超过美国,且恢复更快。中美TFP走势分化主要是由于技术创新发展和产业结构转型存在阶段性差别,以及中国市场化改革和研发创新投入等带来的改革创新红利。为持续提高全要素生产率,本文建议继续深化市场化改革、加快高水平开放,不断建设以实体经济为支撑的现代化产业体系。

关键词：全要素生产率增长核算高质量发展

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Metal–ligand interfaces for well-defined gold nanoclusters

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Science China Chemistry 2024年第3期67卷 806-823页

作者： Dan yang Yating Wu Zhaotong Yuan Chunmei Zhou Yihu Dai Xiaoyue Wan yan Zhu yanhui yang Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China College of Material and Chemical Engineering Minjiang UniversityFuzhou 350108China

Ligand engineering for well-defined gold nanoclusters(Au NCs) is getting more extensive attention. Organizing the Au-ligand interfaces on gold NCs can achieve the structural and functional control. This review focuses on the Au-ligand interfaces including gold-phosphorus(Au-P), gold-sulfur(Au-S), gold-selenium(Au-se), gold-carbon(Au-C), and gold-nitrogen(Au-N), derived from the bonding between Au atoms and the different ligands(e.g., organic phosphine, thiolate, selenolate, alkynyl,n-heterocyclic carbene and nitrogenous ligands). The formation mechanism of Au-ligand interfaces is well discussed. In addition, the effects of Au-ligand interfaces on the stability, optical property, and catalysis are also presented. We hope the advances in this research area can boost the development of Au NC sciences.

关键词： Au nanoclusters well-defined structures metal–ligand interfaces formation mechanism structure–property correlation

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Ocular surface in patients with different degrees of myopia

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1313-1321页

作者： yan-Yun Lyu Shuang Wang Xiao-Niao Chen Zhen-Yu Wang Shan-Shan Huang yan Yuan Hong-Shuang Lu Wen-Li yang Li-Ya Qiao Lei Tian Ying Jie Tongren Eye Care Center Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical University and Beijing Ophthalmology and Visual Sciences Key LaboratoryBeijing 100730China Department of Ophthalmology the Third Medical Center of Chinese People’s Liberation Army General HospitalBeijing 100039China Department of Ophthalmology and Visual Science Tokyo Medical and Dental UniversityTokyo 113-8510Japan

AIM:To investigate the clinical features of the ocular surface in patients with different degrees of ***:A cross-sectional study was conducted involving 122 participants with myopia in Beijing Tongren Hospital from February to June,*** completing the Ocular Surface Disease Index(OSDI)score scale,measurements were taken for refraction,biometric parameters and ocular surface *** prevalence,severity and related parameters of the dry eye among different groups based on axial length(AL)were *** analysis was performed between ocular surface parameters and refraction/biometric measurement ***:Statistically significant differences were observed in refractive error,corneal thickness,anterior chamber depth,and subfoveal choroidal thickness among the groups(all Pse in AL,the incidence and severity of dry eye increased significantly(Psed significantly(Pse;both Pse,and corneal astigmatism(AST;all Pse(both Pset in myopic *** longer the AL,the more severe the dry eye is,with the increased CFS spots and tear film ***,se and AST exhibit negative correlations with dry eye symptom scores and ocular surface parameters.

关键词： myopia axial length ocular surface dry eye

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