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MSC-YOLO:Improved YOLOv7 Based on Multi-Scale Spatial Context for Small Object Detection in UAV-View

Computers, Materials & Continua 2024年第4期79卷 983-1003页

作者： Xiangyan tang Chengchun Ruan Xiulai li Binbin li Cebin Fu School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou570228China

Accurately identifying small objects in high-resolution aerial images presents a complex and crucial task in thefield of small object detection on unmanned aerial vehicles(UAVs).This task is challenging due to variations inUAV flight altitude,differences in object scales,as well as factors like flight speed and motion blur.To enhancethe detection efficacy of small targets in drone aerial imagery,we propose an enhanced You Only Look Onceversion 7(YOLOv7)algorithm based on multi-scale spatial context.We build the MSC-YOLO model,whichincorporates an additional prediction head,denoted as P2,to improve adaptability for small objects.We replaceconventional downsampling with a Spatial-to-Depth Convolutional Combination(CSPDC)module to mitigatethe loss of intricate feature details related to small objects.Furthermore,we propose a Spatial Context Pyramidwith Multi-Scale Attention(SCPMA)module,which captures spatial and channel-dependent features of smalltargets acrossmultiple scales.This module enhances the perception of spatial contextual features and the utilizationof multiscale feature information.On the Visdrone2023 and UAVDT datasets,MSC-YOLO achieves remarkableresults,outperforming the baseline method YOLOv7 by 3.0%in terms ofmean average precision(mAP).The MSCYOLOalgorithm proposed in this paper has demonstrated satisfactory performance in detecting small targets inUAV aerial photography,providing strong support for practical applications.

关键词： Small object detection YOLOv7 multi-scale attention spatial context

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Fluorescent Probes for Cysteine and Cysteine Oxidation Imaging

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Chemical Research in Chinese Universities 2024年第2期40卷 225-236页

作者： ZHANG Xia li Guocheng PAN Wei li Na li Yanhua tang Bo College of Chemistry Chemical Engineering and Materials ScienceKey Laboratory of Molecular and Nano ProbesMinistry of EducationCollaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of ShandongInstitute of Molecular and Nano ScienceShandong Normal UniversityJinan250014P.R.China Laoshan Laboratory Qingdao266237P.R.China

Cysteine is an important regulator of redox processes.Due to the nucleophilic and oxidative sensitivity,cysteine residues in proteins can be oxidized by intracellular reactive oxygen species(ROS),which can lead to protein structural and functional changes.Hence,the development of fluorescent probes to image cysteine and cysteine oxidation is of great significance for the study of redox homeostasis in living system.In this review,the development of fluorescent probes for imaging cysteine and cysteine oxidation was summarized.Moreover,we further analyzed defects of the reported fluorescent probes and made suggestions for the future development of fluorescent probes.We expect that this review can not only provide a deeper understanding of the role of cysteine and cysteine oxidation in oxidative stress,but also broaden the application of fluorescent probes in imaging cysteine and cysteine oxidation.

关键词： Cysteine Cysteine oxidation Fluorescent probe Oxidative stress

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The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： li Zhenpeng YAN Zhihua YANG Jian tang Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex networks.In this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in 1972.The proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given timestamp.Empirical analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency distribution.This paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure entropy.Importantly,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

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Promoting higher-valent pediatric combination vaccines in China: challenges and recommendations for action

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Infectious Diseases of Poverty 2024年第1期13卷 74-84页

作者： Jiuling li Shu Chen dwin Asturias Shenglan tang Fuqiang Cui Global Health Research Center Duke Kunshan UniversityKunshanJiangsuChina ARC Centre of Excellence in Population Ageing Research(CEPAR) Universityof New SouthWalesSydneyAustralia School of Risk and Actuarial Studies University of New South WalesSydneyAustralia Department of Pediatrics University of Colorado School of MedicineAuroraCOUSA Center for Global Health Colorado School of Public HealthAuroraCOUSA Department of Epidemiology Colorado School of Public HealthAuroraCOUSA Duke Global Health Institute Duke UniversityDurhamNCUSA SingHealth Duke-NUS Global Health Institute Duke-NUSSingaporeSingapore Department of Laboratorial Science and Technology School of Public HealthPeking UniversityBeijingChina Vaccine Research Center School of Public HealthPeking UniversityBeijingChina

Many countries have adopted higher-valent pediatric combination vaccines to simplify vaccination schedules and minimize health expenditures and social costs.However,China is conservative in the use of pediatric combina-tion vaccines.By reviewing and synthesizing quantitative and qualitative data,in this commentary we identify gaps and challenges to combination vaccine use and make recommendations for promoting use of higher-valent pediatric combination vaccines in China.Challenges are in four dimensions:(1)legislation and regulation,(2)immunization schedule design,(3)vaccine awareness and price,and(4)research and development capacity.To optimize the use of combination vaccines to reduce vaccine-preventable disease burden,we make recommendations that address key challenges:(1)develop policies and regulations to strengthen enforcement of the Vaccine Administration Law and remove regulatory hurdles that hinder combination vaccine research and development,(2)establish an evi-dence-informed policy-making mechanism for combination vaccines,(3)resolve immunization schedule conflicts between monovalent and combination vaccines,and(4)implement effective interventions to increase vaccine awareness and reduce price.

关键词： Combination vaccine National immunization program Childhood immunization Vaccine-preventable disease

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Bimetal MOF-derived NiFe-P nanocomposites coupled with Cu_(3)P nanoparticles to construct tandem electron transfer channels for photocatalytic hydrogen evolution

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Journal of Environmental Sciences 2024年第3期137卷 333-346页

作者： Haiyan Zhang Shitao Yang Peng Zhu Senpei tang Ming li College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Account Hunan University of Technology and BusinessChangsha 410205China

Finely modulated light-induced charge separation and transfer is a central challenge to achieve efficient photocatalysis.Although progress has been made in this field,most of the previous research works focused on the separation or migration of photogenerated carriers but did not build a bridge between the two.How to realize the strong driving and precise migration of carriers has become the focus of our work.We report an ingeniously designed ternary heterojunction.Taking NiFe-MOF as the“parent material”,the FeP_(4)/Ni_(x)P_(y)heterojunction is derived in situ while maintaining the frame structure through gas-solid reaction,and finally the Z-type electron transfer is realized.With Cu_(3)P anchoring spindle matrix,an electron transport tunnel is opened up in Cu_(3)P/FeP_(4)/Ni_(x)P_(y)ternary heterojunction under the action of p-n heterojunction built-in electric field driving and accurate energy band matching.The strong driving force of the built-in electric field provides an inexhaustible power for the transmission of electrons,and the fine series of electron transmission channels realizes the precise transmission of electrons.The above fine design makes the perfect fit between the built-in electric field and the electron transfer channel,which not only effectively improves the embarrassing situation of insufficient electron driving force of hydrogen evolution reaction in the previous research,but also makes up for the weakening of semi-conductor reduction ability caused by the construction of traditional p-n heterostructures.This research work provides a new idea for the construction of multiple heterostructures and the design of fine interface engineering in the future.

关键词： Cu_(3)P/FeP_(4)/Ni_(x)P Built-in electric field Electron transfer channels Photocatalysis

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Optimal operation of Internet Data Center with PV and energy storage type of UPS clusters

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Global Energy Interconnection 2024年第1期7卷 61-70页

作者： Man Chen Yuxin Zhao Yuxuan li Peng Peng Xisheng tang CSG PGC Energy Storage Research Institute Guangzhou 510000P.R.China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

With the development of green data centers,a large number of Uninterruptible Power Supply(UPS)resources in Internet Data Center(IDC)are becoming idle assets owing to their low utilization rate.The revitalization of these idle UPS resources is an urgent problem that must be addressed.Based on the energy storage type of the UPS(EUPS)and using renewable sources,a solution for IDCs is proposed in this study.Subsequently,an EUPS cluster classification method based on the concept of shared mechanism niche(CSMN)was proposed to effectively solve the EUPS control problem.Accordingly,the classified EUPS aggregation unit was used to determine the optimal operation of the IDC.An IDC cost minimization optimization model was established,and the Quantum Particle Swarm Optimization(QPSO)algorithm was adopted.Finally,the economy and effectiveness of the three-tier optimization framework and model were verified through three case studies.

关键词： Three-tier optimization framework Energy storage type of the UPS EUPS cluster classification method Quantum Particle Swarm Optimization

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Effective Ultra-High-Speed Identification Scheme of lightning Strikes Suitable for VSC-Based DC Grids

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 548-561页

作者： Longlong Chen Xiangyu Pei Xiaoguang Wei Pengzhi li Guangfu tang North China Electric Power University(NCEPU) Beijing 102206China Changsha University of Science and Technology Changsha 410114China State Key Laboratory of Advanced Power Transmission Technology State Grid Smart Grid Research Institute Co.Ltd.Beijing 102209China

To ensure their sound and continuous operation to the greatest extent,VSC-based DC girds have extremely stringent requirements for transmission line relay protection.In terms of guaranteeing their reliability,accurate identification of lightning strikes on DC transmission lines is one of the urgent key problems to be solved.An effective ultra-high-speed identification scheme of lightning strikes suitable for the VSC-based DC grid is proposed in this paper.First,an 1-mode reverse voltage traveling wave(RVTW)is constructed applying the pole-mode transformation theory.Next,fault traveling wave propagation characteristics along the DC transmission line are analyzed in depth utilizing Peterson's law.Then,differences of time-frequency electromagnetic transient characteristics of 1-mode RVTWs between disturbances and faults caused by lightning strikes are distinguished in detail by means of the classical wavelet transformation multi-resolution analysis theory.Finally,extensive simulations are carried out to evaluate the performance of the proposed identification scheme,and by which its excellent rapidity,reliability and robustness are validated.Index Terms-lightning-strike identification,Multi-resolution analysis,Relay protection,Traveling-wave protection,VsC-based DC grid,Wavelet transformation.

关键词： lightning-strike identification Multi-resolution analysis Relay protection Traveling-wave protection VsC-based DC grid Wavelet transformation

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Effects of host identity on the gut microbiota:A comparative study on three microtinae species

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Animal Models and Experimental Medicine 2024年第2期7卷 98-105页

作者： Zhen Yao Wenli Zhao Baohong tang Qinghua li Zhenlong Wang School of life Sciences Zhengzhou UniversityZhengzhouHenan ProvinceP.R.China

Background:Gut microbiota exert an immense effect on host health and host environmental adaptation.Furthermore,the composition and structure of gut microbiota are determined by the environment and host genetic factors.However,the relative contribution of the environment and host genetic factors toward shaping the structure of gut microbiota has been poorly understood.Methods:In this study,we characterized the fecal microbial communities of the closely related voles Neodon fuscus,Lasiopodomys brandtii,and L.mandarinus after caged feeding in the laboratory for 6 months,through high-throughput sequencing and bioinformatics analysis.Results:The results of pairwise comparisons of N.fuscus vs.L.brandtii and L.mandarinus vs.L.brandtii revealed significant differences in bacterial diversity and composition after domestication.While 991 same operational taxonomic units(OTUs)were shared in three voles,there were 362,291,and 303 species-specific OTUs in N.fuscus,L.brandtii,and L.mandarinus,respectively.The relative abundances of Proteobacteria and Prevotella,which are reported to be enriched in high-altitude populations,were significantly higher in high-altitude N.fuscus than in low-altitude L.brandtii after domestication.Firmicutes,which produce various digestive enzymes for energy metabolism,and Spirochaetes,which can degrade cellulose,were found in higher abundance in subterranean L.mandarinus than that in L.brandtii which dwells on the earth surface.Conclusion:Our findings showed that some components of gut microbiota still maintained dominance even when different host species are reared under the same environmental conditions,suggesting that these bacteria are substantially influenced by host factors.

关键词： gut microbiota high-altitude Lasiopodomys brandtii Neodon fuscus

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Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

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Digital Communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan li Xiao tang Ruonan Zhang Haotong Cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of Computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum efficiency.To tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded cell.To fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent cells.To tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV position.Then,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation schemes.We further propose an iterative power allocation algorithm based on the sequential convex approximation theory.The simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

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Experimental study on the size effect on the equation of state of concretes under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 160-167页

作者： Mei li Jian Cui Yanchao Shi Baijian tang Xin Chen Key Laboratory of Coast Civil Structural Safety of the Ministry of Education Tianjin UniversityTianjin 300072China School of Civil Engineering Suzhou University of Science and Technology1701 Binhe RoadSuzhou 215011JiangsuChina School of Civil Engineering Tianjin UniversityTianjin 300072China

Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which depicts the shear properties of concrete.The experiments on the EoS of concrete is always challenging due to the technical difficulties and equipment limitations,especially for the specimen size effect on the EoS.Although some researchers investigate the shock properties of concretes by fly-plate impact tests,the specimens used in their tests are usually in one size.In this paper,the fly-plate impact tests on concrete specimens with different sizes are performed to investigate the size effect on the shock properties of concrete materials.The mechanical background of the size effect on the shock properties are revealed,which is related to the lateral rarefaction effect and the deviatoric stress produced in the specimen.According to the tests results,the modified EoS considering the size effect on the shock properties of concrete are proposed,which the bulk modulus of concrete is unpredicted by up to 20% if size effects are not accounted for.

关键词： Concrete Equation of state Size effect Shock wave Fly-plate impact test

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