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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 and Continua 2024年第3期80卷 3713-3731页

作者： Huangfu z. Li s. Yan L. school of Information Engineering North China University of Water Resources and Electric Power Zhengzhou 450046 China

Addressing the challenges in detecting surface floating litter in artificial lakes, including complex environments, uneven illumination, and susceptibility to noise and weather, this paper proposes an efficient and lightweight Ghost-YOLO (You Only Look Once) v8 algorithm. The algorithm integrates advanced attention mechanisms and a small-target detection head to significantly enhance detection performance and efficiency. Firstly, an sE (squeeze-and-Excitation) mechanism is incorporated into the backbone network to fortify the extraction of resilient features and precise target localization. This mechanism models feature channel dependencies, enabling adaptive adjustment of channel importance, thereby improving recognition of floating litter targets. secondly, a 160 × 160 small-target detection layer is designed in the feature fusion neck to mitigate semantic information loss due to varying target scales. This design enhances the fusion of deep and shallow semantic information, improving small target feature representation and enabling better capture and identification of tiny floating litter. Thirdly, to balance performance and efficiency, the GhostConv module replaces part of the conventional convolutions in the feature fusion neck. Additionally, a novel C2fGhost (CsPDarknet53 to 2-stage Feature Pyramid Networks Ghost) module is introduced to further reduce network parameters. Lastly, to address the challenge of occlusion, a new loss function, WIoU (Wise Intersection over Union) v3 incorporating a flexible and non-monotonic concentration approach, is adopted to improve detection rates for surface floating litter. The 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 volu

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

Precise determination of the pole position of the exotic z_(c)(3900)

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science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 84-90页

作者： Yun-Hua chen Meng-Lin Du Feng-Kun Guo school of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China school of Physics University of Electronic Science and Technology of ChinaChengdu 611731China CAs Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We perform a unified description of the experimental data of the π^(+)π^(-)and J/ψπ^(±)invariant mass spectra for e^(+)e^(-)→J/ψπ^(+)π^(-)and the D^(0)D^(*-)mass spectrum for e^(+)e^(-)→D^(0)D^(*-)π^(+)at e^(+)e^(-)center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-DD^(*)coupled-channel interaction respecting unitarity,and the strong ππ-KK final state interaction using dispersion *** analysis leads to a precise determination of the z_(c)(3900)pole with the pole mass and width(3880.7±1.7_(stat)±22.4_(syst))MeV and(35.9±1.4_(stat)±15.3_(syst))MeV,respectively,and hints at that the DD^(*)molecular and non-molecular components are of similar importance in the z_(c)(3900)formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

Implications of the stellar Mass Density of High-z Massive Galaxies from JWsT on Warm Dark Matter

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Research in Astronomy and Astrophysics 2024年第1期24卷 128-134页

作者： Hengjie Lin Yan Gong Bin Yue Xuelei chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China science Center for China space station Telescope National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100871China

A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb space Telescope(JWsT),and it may require a high star formation ***,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR *** dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass *** provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization *** the other hand,the constraints on the properties of WDM can be derived from the JWsT *** this work,we study WDM as a possible solution to reconcile the JWsT stellar mass density of high-z massive galaxies and reionization *** find that,the JWsT high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM *** using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWsT high-z comoving cumulative stellar mass density and the reionization history.

关键词： Cosmology (cosmology:)dark matter (cosmology:)large-scale structure of universe

The Lambert-G Family:Properties,Inference,and Applications

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Computer Modeling in Engineering & sciences 2024年第7期140卷 513-536页

作者： Jamal N.Al Abbasi Ahmed z.Afify Badr Alnssyan Mustafa s.shama Accounting Department Ashur UniversityBaghdad10011Iraq Department of statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt Department of Management Information systems and Production Management College of Business and EconomicsQassim UniversityBuraydah51452Saudi Arabia Department of Basic sciences Common First Year(CFY)King Saud UniversityRiyadh11362Saudi Arabia Department of Mathematics and statistics Osim Higher Institute of Administrative ScienceOsim12961Egypt

This study proposes a new flexible family of distributions called the Lambert-G *** Lambert family is very flexible and exhibits desirable *** three-parameter special sub-models provide all significantmonotonic and non-monotonic failure rates.A special sub-model of the Lambert family called the Lambert-Lomax(LL)distribution is *** expressions for the LL statistical properties are *** of the LL distribution are addressed mathematically based on its hazard *** estimation of the LL parameters is discussed using six estimation *** performance of this estimation method is explored through simulation *** usefulness and flexibility of the LL distribution are demonstrated empirically using two real-life data *** LL model better fits the exponentiated Lomax,inverse power Lomax,Lomax-Rayleigh,power Lomax,and Lomax distributions.

关键词： Lambert function Lomax distribution maximum likelihood hazard function statistical model simulation

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang shenyang National Laboratory for Materials science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and s.z. stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification scanning-transmission electron microscopy.

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed sintering and Post Treatment

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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue s.Y.Peng X.zhang C.N.He Y.z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China school of Materials science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACs and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability strength Electrical conductivity

Efficacy evaluation of zirconia crown on primary molars with caries defects

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Hua Xi Kou Qiang Yi Xue za zhi / West China Journal of stomatology 2024年第5期42卷 652-659页

作者： Deng s. Niu s. Gao Q. zhang L. chen z. Liu M. Dept. of stomatology Shenzhen Children’ s Hospital Shenzhen 518026 China Dept. of stomatology The People’ s Hospital of Longhua Shenzhen 518109 China Dept. of Maxillofacial surgery Shenzhen Second People’ s Hospital Shenzhen 518029 China

Objective This study aimed to estimate the therapeutic effects of preformed metal crown (PMC) and prefabricated zirconia crowns (zC) on decayed primary morals in children, as well as to analyze the possible influencing factors. Methods A retrospective cohort study was performed on the data of 192 patients (aged 3 to 8) in the stomatological Department of shenzhen Children’s Hospital from October 2021 to December 2021. The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and zC, including 96 cases (96 caries) in the PMC group and 96 cases (96 caries) in the zC group. Oral clinical examination was performed at 3 months, 1 year, and 2 years after treatment, overwiewing the clinical therapeutic effects and periodontal status of PMC and zC groups, as well as recording the crown integrity, gingival index (GI), probing bleeding index (BI), plaque index (PLI) and various prosthetic indices. Results No significance differences existed in the periodontal status of PMC and zC groups at 3 months, 1 year, and 2 years after treatment (P>0.05). However, the GI, BI, and PLI in the PMC group were higher than those in the zC group at 3 months, 1 year, and 2 years after treatment, and the difference was dramatically significant (Psignificances difference existed in various prosthetic indices (P>0.05), as well as in the GI, BI, and PLI, between the two groups (P>0.05). No significant differences existed in various prosthetic indices between genders after PMC restoration (P>0.05). The scores of girls in various prosthetic indices after zC restoration were higher than those of boys (Pson correlation analysis indicated an inverse correlation between age in the PMC group and the GI, BI, PLI, and FDI indices (PzC group (P>0.05). Conclusion PMC and zC can be applied to restore deciduous molar caries. The periodontal status of deciduous teeth in zC group was superior to that in the PMC group. The

关键词： gingival index plaque index prefabricated zirconia crowns preformed metal crown probing bleeding index

Compressive property and energy absorption characteristic of interconnected porous Mg-zn-Y alloys with adjusting Y addition

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Journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： J.A.Liu s.J.Liu B.Wang W.B.sun X.J.Liu z.W.Han College of Materials science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for Bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-zn-Y ternary phases appear:I-phase(Mg_(3)zn_(6)Y),W-phase(Mg_(3)zn_(3)Y_(2)),and LPsO phase(Mg_(12)znY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 MJ/m^(3)to 10.97 MJ/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

Importance of diet and intestinal microbiota in the prevention of colorectal cancer-colonoscopy early screening diagnosis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3428-3435页

作者： Miljana z Jovandaric Department of Neonatology Clinic for Gynecology and ObstetricsUniversity Clinical Center of SerbiaBelgrade 11070Serbia

Colorectal cancer is a term used to describe colon and rectal cancer,which is the third most common type of cancer.A MEDLINE and PubMed search resulted in the inclusion of manuscripts written in the last 10 years,using keywords relevant to the topic of the *** analyzing the aim of the searched studies and manuscripts,adequate articles were included that described the stated *** frequency of colorectal cancer varies with climate,nutrition,and many other factors,primarily endogenous,hereditary,intestinal microbiome,as well as external factors,such as exposure of the individual to stress,and bad eating *** cancer and rectal cancer or colorectal cancer in general in the early stages of the disease,may not show symptoms or are barely *** cancer symptoms will most often not develop until the disease has progressed to stage 2 or *** screening tests for colon or rectal cancer,especially colonoscopy,are recommended as part of a regular checkup for people aged 50 years or younger who are at high risk due to a family history of the disease or other *** and colonoscopy as an early screening method play an important role in the prevention of colorectal cancer.

关键词： Colorectal cancer Causes symptoms screening Diet and colonoscopy