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Impact of LHCb 13 TeV W and Z pseudo-data on the parton distribution functions

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Chinese Physics C 2021年第2期45卷 211-221页

作者： Qilin Deng Qundong Han Hang Yin Sayipjamal Dulat tie-jiun hou C.–P.Yuan Institute of Particle Physics Central China Normal UniversityWuhan 430079 China School of Physics Science and Technology Xinjiang UniversityUrumqi 830046 China Department of Physics College of SciencesNortheastern UniversityShenyang 110819 China Department of Physics and Astronomy Michigan State UniversityEast LansingMI 48824 USA

We study the potential of the LHCb 13 TeV single W±and Z boson pseudo-data for constraining the parton distribution functions(PDFs)of the *** an example,we demonstrate the sensitivity of the LHCb 13 TeV data,collected with integrated luminosities of 5fb^(-1) and 300 fb^(-1) ,to reducing the PDF uncertainty bands of the CT14HERA2 PDFs,using the error PDF updating package *** sensitivities of various experimental observables are ***,sizable reductions in PDF uncertainties can be observed in the 300fb^(-1) data sample,particularly in the small-x *** double-differential cross section measurement of Z boson pT and rapidity can greatly reduce the uncertainty bands of u and d quarks in almost the whole x range,as compared to various single observable measurements.

关键词： PDF W/Z boson production LHCb

Reduction of PDF uncertainty in the measurement of the weak mixing angle at the ATLAS experiment

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Chinese Physics C 2021年第5期45卷 1-18页

作者： Yao Fu Siqi Yang Minghui Liu Liang Han tie-jiun hou Carl Schmidt Chen Wang C-P.Yuan Department of Modem Physics University of Science and Technology of ChinaJinzhai Road 96Hefei 230026China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Department of Physics and Astronomy Michigan State UniversityEast LansingMI 48823USA

We investigate the parton distribution function(PDF)uncertainty in the measurement of the effective weak mixing angle sin2θ^(l)_(eff)at the CERN Large Hadron Collider(LHC).The PDF-induced uncertainty is large in proton-proton collisions at the LHC due to the dilution *** measurement of the Drell-Yan forward-backward asymmetry(ApB)at the LHC can be used to reduce the PDF uncertainty in the sin2θ^(l)_(eff)***,when including the full mass range of lepton pairs in the AFB data analysis,the correlation between the PDF updating procedure and the sin2θ^(l)_(eff) extraction leads to a sizable bias in the obtained sin2θ^(l)_(eff)*** our studies,we find that the bias can be significantly reduced by removing Drell-Yan events with invariant mass around the Z-pole region,while most of the sensitivity in reducing the PDF uncertainty ***,the lepton charge asymmetry in the^boson events as a function of the rapidity of the charged leptons,A±(ηl),is known to be another observable which can be used to reduce the PDF uncertainty in the sin2θ^(l)_(eff)*** constraint from A±(ηl)is complementary to that from AFB,and thus no bias affects the sin2θ^(l)_(eff)*** studies are performed using the error PDF Updating Method Package(ePump),which is based on Hessian updating *** this article,the CT14HERA2 PDF set is used as an example.

关键词： parton distribution function weak mixing angle hadron collider experiment electroweak

The impact of ATLAS and CMS single differential top-quark pair measurements at √s=8 TeV on CTEQ-TEA PDFs

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Chinese Physics C 2021年第2期45卷 222-239页

作者： Musajan Kadir Alim Ablat Sayipjamal Dulat tie-jiun hou Ibrahim Sitiwaldi School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China Department of Physics Northeastern UniversityShenyang 110819China

By applying the Error PDF Updating Method,we analyze the impact of the absolute and normalized single differential cross-sections for top-quark pair production data from the ATLAS and CMS experiments at the Large Hadron Collider,at a center-of-mass energy of √s=8TeV,on the CT14HERA2 *** find that the top quark pair single differential distributions provide minor constraints on the CT14HERA2 gluon PDF when the nominal CT14HERA2 inclusive jet production data are included in the *** constraints on the gluon distribution are present when the jet data are removed(CT14HERA2mJ)and/or when increased weights are given to the top data in the CT14HERA2 *** weighted$t\bar t$data provide significant constraints on the CT14HERA2mJ gluon PDF,which are comparable to those obtained from inclusive jet production ***,we examine the top quark mass sensitivity of the top-quark pair single differential distributions.

关键词： top-quark pair production gluon PDF jet data

A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm

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Petroleum Science 2024年第2期21卷 1135-1148页

作者： tie Yan Rui Xu Shi-Hui Sun Zhao-Kai hou Jin-Yu Feng School of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya572025HainanChina

Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation.

关键词： Intelligent drilling Closed-loop drilling Lithology identification Random forest algorithm Feature extraction

Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao hou Kai hou Xiaopeng WANG Hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was *** non-equilibrium solidification structure of the under cooled alloy samples were *** is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling *** and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were ***-density defects were observed,such as dislocations,stacking faults networks,and twinning *** standard FCC diffraction pattern represents that it is still a single-phase *** on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced *** addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was *** was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear *** electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

Integral Operators Between Fock Spaces

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 265-278页

作者： Yongqing LIU Shengzhao hou School of Mathematics and Statistics Changshu Institute of TechnologySuzhou 215006JiangsuChina School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock *** 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is the normali... 详细信息

关键词： Fock spaces Integral operators Normalized reproducing kernel

Herbivore and native plant diversity synergistically resist alien plant invasion regardless of nutrient conditions

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Plant Diversity 2024年第5期46卷 640-647页

作者： Liping Shan Meng hou Key Laboratory of Wetland Ecology and Environment State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant ***,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(*** enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient *** this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient *** found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native *** inhibition was amplified by highly diverse native ***,the amplified effect between herbivory and native plant diversity was independent of nutrient *** results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory *** synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant *** results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.

关键词： Biological invasion Biotic resistance Diversity conservation Plant-herbivore interactions Resource availability Global change

Fractures interaction and propagation mechanism of multi-cluster fracturing on laminated shale oil reservoir

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Petroleum Science 2024年第4期21卷 2600-2613页

作者： Jia-Xin Lv Bing hou Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Department of Petroleum Engineering China University of Petroleum (Beijing) at Karamay

The continental shale reservoirs of Jurassic Lianggaoshan Formation in Sichuan Basin contain thin lamina, which is characterized by strong plasticity and developed longitudinal shell limestone *** improve the production efficiency of reservoirs by multi-cluster fracturing, it is necessary to consider the unbalanced propagation of hydraulic fractures and the penetration effect of fractures. This paper constructed a numerical model of multi-fracture propagation and penetration based on the finite element coupling cohesive zone method; considering the construction cluster spacing, pump rate,lamina strength and other parameters studied the influencing factors of multi-cluster fracture interaction propagation; combined with AE energy data and fracture mode reconstruction method, quantitatively characterized the comprehensive impact of the strength of thin interlayer rock interfaces on the initiation and propagation of fractures that penetrate layers, and accurately predicted the propagation pattern of hydraulic fractures through laminated shale oil reservoirs. Simulation results revealed that in the process of multi-cluster fracturing, the proportion of shear damage is low, and mainly occurs in bedding fractures activated by outer fractures. Reducing the cluster spacing enhances the fracture system's penetration ability, though it lowers the activation efficiency of lamina. The high plasticity of the limestone interlayer may impact the vertical propagation distance of the main fracture. Improving the interface strength is beneficial to the reconstruction of the fracture height, but the interface communication effect is limited. Reasonable selection of layers with moderate lamina strength for fracturing stimulation, increasing the pump rate during fracturing and setting the cluster spacing reasonably are beneficial to improve the effect of reservoir stimulation.

关键词： Laminated shale Multi-cluster fracturing Cross-layer Cohesive zone model Acoustic emission technique

In-Plane Dynamic Crushing Behaviors of a Vertex-Based Hierarchical Auxetic Honeycomb

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Acta Mechanica Solida Sinica 2024年第1期37卷 53-62页

作者： Yichen Zan Xiuhui hou Zichen Deng School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi'an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China

Auxetic metamaterials,which exhibit the negative Poisson’s ratio(NPR)effect,have found wide applications in many engineering ***,their high porosity inevitably weakens their bearing capacity and impact *** improve the energy absorption efficiency of auxetic honeycombs,a novel vertex-based hierarchical star-shaped honeycomb(VSH)is designed by replacing each vertex in the classical star-shaped honeycomb(SSH)with a newly added self-similar *** analytical model is built to investigate the Young’s modulus of VSH,which shows good agreement with experimental results and numerical *** in-plane dynamic crushing behaviors of VSH at three different crushing velocities are investigated,and empirical formulas for the densification strain and plateau stress are *** results reveal more stable deformation modes for VSH,attributed to the addition of self-similar star-shaped ***,compared with SSH under the same relative densities,VSH exhibits better specific energy absorption and higher plateau ***,VSH is verified to be a better candidate for energy absorption while maintaining the auxetic *** study is expected to provide a new design strategy for auxetic honeycombs.

关键词： Vertex-based hierarchical star-shaped honeycomb Auxetic honeycomb Energy absorption Plateau stress Negative Poisson's ratio