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The Existence of Entropy Solutions to Some Parabolic Problems with L^1 Data

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Acta Mathematica Sinica,English Series 2002年第1期18卷 119-128页

作者： LI feng Quan department of mathematics. qufu normal university, Shandong 273165. P. R. china department of mathematics Qufu Normal University Shandon P. R. China

In this paper, an existence result of entropy solutions to some parabolic problems is established. The data belongs to L^1 and no growth assumption is made on the lower-order term in divergence form.

关键词： Existence Parabolic problems Entropy solutions L^1 Data

Analysis of the one-decoy-state SARG04 quantum cryptography protocol in the presence of afterpulse effects

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Communications in Theoretical Physics 2024年第6期76卷 66-71页

作者： hu Nian Ya-feng Nie Chun-Mei Zhang Liang-Liang Lu Key Laboratory of Optoelectronic Technology of Jiangsu Province School of Physical Science and TechnologyNanjing Normal UniversityNanjing 210023China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Hefei National Laboratory Hefei 230088China

The SARG04 quantum key distribution protocol can offer greater robustness against photon number splitting attacks than the BB84 protocol that is implemented with weak *** this paper,we propose a tight key analysis for the SARG04 protocol,by considering the one-decoy method and investigating its performance under the influence of a detector *** results demonstrate that an increase in block size leads to a slight increase in both the secure key rate and the maximum transmission ***,the detector afterpulse plays a crucial role in practical applications and has a more pronounced effect on the SARG04 protocol compared to the BB84 protocol.

关键词： Quantum key distribution SARG04 protocol one decoy afterpulse

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-feng Zhou Yu Long Yan-Liang Yi Cheng Deng Lian-Xi hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Migration pattern of a population of Barn Swallows(Hirundo rustica)breeding in East Asian tropical region

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Avian Research 2024年第3期15卷 299-307页

作者： Li Tian Yu Liu Yang Wu Zimei feng Dan hu Zhengwang Zhang Key Laboratory for Biodiversity Sciences and Ecological Engineering Ministry of EducationCollege of Life SciencesBeijing Normal UniversityBeijing100875China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100107China Life Science and Technology School Lingnan Normal UniversityZhanjiang524048China

Birds exhibit a high degree of migratory diversity,which is influenced by various ecological factors and life history *** studies on tropical bird migration,of which research is scarce,and comparing it with temperate birds can enhance our understanding of bird migration behaviour and its underlying *** this study,we explored the migration behaviour of a breeding population of the Barn Swallow(Hirundo rustica)in Zhanjiang,southern china,a region located in the northern tropics,using light-level *** 2021 to 2023,we deployed geolocators on 92 breeding swallows and retrieved geolocators successfully from 23 *** swallows all exhibited migratory behaviour,and wintering on various islands in Southeast *** displayed sex differences in their wintering *** males concentrated in Borneo,while females primarily chose Borneo but also dispersed to the Philippines,South china Sea,and Vietnam for *** studied swallow population adopted a seasonal migration pattern of“indirect in autumn,direct in spring”,bypassing the ecological barrier of the South china Sea in autumn and tending to directly cross it in spring ***,the distance and duration of autumn migration was significantly longer than those of the spring *** to temperate Barn Swallows,the Barn Swallow population breeding in Zhanjiang adopts a pattern of“intra-tropical migration”and initiates autumn migration *** formation of their migration pattern may be limited by ecological and physiological factors.

关键词： Asia Chain migration Light-level geolocators Migration Northern tropics

A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3524-3543页

作者： Jun Zhao Xia-Ting feng Jia-Rong Wang Liang hu Yue Guo Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in *** this device,the complete shearedeformation process and long-term shear creep tests could be performed on rocks under constant normal stiffness(CNS)or constant normal loading(CNL)conditions in real-time at high temperature and true-triaxial *** the research and development process,five key technologies were successfully broken through:(1)the ability to perform true-triaxial compressioneshear loading tests on rock samples with high stiffness;(2)a shear box with ultra-low friction throughout the entire stress space of the rock sample during loading;(3)a control system capable of maintaining high stress for a long time and responding rapidly to the brittle fracture of a rock sample as well;(4)a refined ability to measure the volumetric deformation of rock samples subjected to true triaxial shearing;and(5)a heating system capable of maintaining uniform heating of the rock sample over a long *** developing these technologies,loading under high true triaxial stress conditions was *** apparatus has a maximum normal stiffness of 1000 GPa/m and a maximum operating temperature of 300*** differences in the surface temperature of the sample are constant to within5*** types of true triaxial shear tests were conducted on homogeneous sandstone to verify that the apparatus has good performance and *** results show that temperature,lateral stress,normal stress and time influence the shear deformation,failure mode and strength of the *** novel apparatus can be reliably used to conduct true-triaxial shear tests on rocks subjected to high temperatures and stress.

关键词： True-triaxial shear apparatus Rocks Complete shear stressedeformation process Creep Real-time high-temperature

Rim^(18)F-fluorodeoxyglucose uptake of hepatic cavernous hemangioma on positron emission tomography/computed tomography:A case report

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World Journal of Clinical Cases 2024年第13期12卷 2243-2247页

作者： Yong-An hu Ya-Xin Guo Qi-feng huang department of Nuclear Medicine Jinhua Hospital of Zhejiang UniversityJinhua Municipal Central HospitalJinhua 321000Zhejiang ProvinceChina

BACKGROUND Peripheral FDG accumulation in a hepatic hemangioma presenting in a patient with prolonged fever is ***,clinicians should pay close attention to patients with hepatic *** SUMMARY A 54-year-old woman with a 4-wk history of daily fevers was admitted to our hospital.A whole body^(18)-Fluordesoxyglucose(PET-FDG)positron emission tomography/computed tomography(PET/CT)was performed to elucidate the source of the ***,whole body^(18)-FDG PET/CT raised the suspicion of a malignant lesion because of peripheral FDG accumulation(SUVmax 3.5 g/mL)higher than that of the normal liver parenchyma(SUVmax 1.6 g/mL)surrounding a hypoactive area,and no other abnormalities were ***,the patient underwent liver mass *** showed a hepatic cavernous hemangioma with fatty infiltration around the *** fever disappeared four days after surgery and the patient did not present any complications during *** Fatty infiltration in the peripheral parts of hepatic cavernous hemangioma may lead to subacute inflammation which further activate the Kupffer *** may cause prolonged fever and peripheral rim FDG accumulation on PET/CT.

关键词： ^(18)-Fluordesoxyglucose positron emission tomography/computed tomography Hepatocellular carcinoma Fever Fatty infiltration Case report

Patterns and drivers of avian taxonomic and phylogenetic beta diversity in china vary across geographical backgrounds and dispersal abilities

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Zoological Research 2024年第1期45卷 125-135页

作者： Jian-Chao Liang Zhi-feng Ding Chun-Lin Li Yi-Ming hu Zhi-Xin Zhou Gan-Wen Lie Xiao-Nan Niu Wen-Bin huang hui-Jian hu Xing-feng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong 510260China School of Resources and Environmental Engineering Anhui UniversityHefeiAnhui 230601China Guangdong Eco-Engineering Polytechnic GuangzhouGuangdong 510520China huizhou Institute of Forestry(huizhou Botanical Garden Management Service Center) HuizhouGuangdong 516001China Administration of National Nature Reserve for Marine Ecology of Guangdong Nanpeng Islands ShantouGuangdong 515900China Zhejiang Zhoushan Archipelago Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity ***,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in china vary across(1)regions on both sides of the hu Line,which demarcates china’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal *** and PBD were calculated and partitioned into turnover and nestedness components using a moving window *** representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental *** distance was considered to assess the impact of dispersal *** partitioning analysis was applied to assess the relative roles of these *** general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental ***,different dominant environmental filters on either side of the hu Line led to divergent beta diversity ***,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,***,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous *** results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological *** a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete ***,a comprehensive understanding of large-scale beta diversity patterns and effective pla

关键词： Beta diversity Environmental filtering Dispersal limitation hu Line Species dispersal ability Breeding birds

Influence of self-similar stresses on scenario earthquake construction:An example along the Tanlu Fault

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Science china Earth Sciences 2024年第5期67卷 1687-1697页

作者： feng hu huajian YAO Houyun YU Zeyu LU Jieyi HOU Song LUO Zhigang SHAO Xiaofei CHEN School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Mengcheng Geophysical National Field Scientific Observatory Hefei 230026China department of Earth and Space Science Southern University of Science and TechnologyShenzhen 518055China Institute of Earthquake Prediction China Earthquake AdministrationBeijing 100036China

As a famous deep and large fault in eastern china,the Tanlu Fault passes through Anhui,Jiangsu,and Shandong and into northeastern *** is important to improve the understanding of seismic hazard assessments in areas near *** start a scenario earthquake simulation in the M7.5 earthquake potential area of the Xinyi-Sihong segment of the Tanlu *** fault rupture length and width are constrained according to the scaling law of large intraplate earthquakes,the background normal stress is depth dependent,and the initial shear stresses are determined using trial and error by matching the earthquake *** the 120 km rupture length of the M7.5 earthquake,we compare the horizontal uniform stress model and self-similar stress perturbation *** findings reveal that the seismic source time function of the horizontal uniform stress model is similar to that of the Haskell model and that of the self-similar stress perturbation model is more similar to that of a real earthquake *** compare the dynamic rupture simulation and ground motion results under four different stress conditions and find that the shorter the characteristic length of the self-similar function is,the rougher the initial *** the M7.5earthquake with an epicenter in the vicinity of Suqian,the Xinyi-Tancheng segment,which is located in the IX-intensity zone north of the epicenter,vibrates more strongly on the northern side than on the southern side due to the influence of the lowvelocity zone and the peak slip *** response spectra analysis at stations in the study area is useful for improving the earthquake resistance capability.

关键词： Scenario earthquakes Self-similar stress Tanlu Fault Dynamic rupture Ground motion

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多输入非线性串级系统的自适应控制

系统工程理论与实践 2001年第12期21卷 30-35页

作者：周绍生冯纯伯曲阜师范大学自动化研究所山东曲阜273165 东南大学自动化研究所江苏南京210096

对一大类含有未知参数的多输入非线性串级系统 ,基于 backstepping递推设计方法 ,进行了自适应控制设计。当自适应控制律作用于该系统时 ,闭环系统的所有信号是有界的。

关键词：自适应控制 V函数多输入非线性串级系统鲁棒控制