检索结果-南通市图书馆

地学前缘 2007年第2期14卷 257-267页

作者： v.t. trofimov.t.i. averkina Lomonosov Moscow State University

文中定义了“工程地质结构”这一术语,讨论了其内容、成因、判别标志与依据、谱系分类及全球实际系列,并对全球及各大洲的超巨型、巨型、大型、中型工程地质结构的分布规律进行了描述。

关键词：工程地质结构超巨型、巨型、大型及中型工程地质结构地球工程地质结构实际系列

vegetation dynamics at the southern edge of the Siberian mountain taiga

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Journal of Mountain Science 2025年第2期22卷 451-465页

作者： iM Sergei t KHARUK viacheslav i PEtROv il'ya A SHUSHPANOv Alexander S DviNSKAYA Maria L ONDAR Sergei O v.N.Sukachev institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia institute of Ecology and Geography Institute of Space and Information TechnologiesSiberian Federal UniversityKrasnoyarsk 660041Russia Laboratory of Biodiversity and Ecology Tomsk State UniversityTomsk 634050Russia institute of Space Research and High technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk 660014Russia Department of Biology and Ecology Tuvan State UniversityKyzyl 667000Russia

the growth,survival,and mortality of conifer species in response to the hydrothermal regime have received considerable *** is expected that the highest sensitiv.t. of trees to the warming-drying climate will occur mainly at the edges of the species *** focused on the responses to climate change of the drought-resistant larch(Larix sibirica)and the moisture-sensitive Siberian pine(Pinus sibirica)along the elev.t.on gradient in the tannu-Ola Ridge,the southern margin where those two species coexist in Siberia by using satellite data(MODiS,Landsat,and microwave),the indexes of gross(GPP)and net(NPP)primary productiv.t.,and tree radial growth index(Gi).We found that since the warming restart in the 2000s,the area of larch-dominated forests increased by~150%while the area of pine-dominated forests decreased by~10%.the Siberian pine has retreated at low elev.t.ons(increased its area at higher *** contrast,the area of larch stands increased in both the uphill and downhill ***(Betula spp.)also increased its area at low elev.t.ons(about+120%).Since 2001,the forested area increased by~5%.A shrubification,i.e.,an increase in the area of shrubs,was observed at high *** uphill rate of timberline and shrubline migration was about 0.3 m/*** the 2000s,vegetation NPP has increased by 13%.A notable correlation between NPP and the Gi of larch and pine was found(r=0.5-0.7).At lower elev.t.ons,NPP positively correlated with precipitation and soil moisture,while air temperature and vPD(vapor pressure deficit)increase inhibited *** high elev.t.ons,the effects of these variables on productiv.t. *** continuous decline of the Siberian pine forest indicates an inev.t.ble retreat of this species at low elev.t.ons and its replacement by larch and birch.

关键词： trees range changes Mountain taiga Siberian larch Siberian pine timberline Shrubification tree uphill migration Forest population dynamics Ecological resilience Habitat suitability

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块系岩体准共振诱发弱夹层拉压损伤断裂研究

岩石力学与工程学报 2025年第1期44卷 114-127页

作者：王凯兴徐伟刚潘一山薛佳琪 OPARiN v N KiRYAEvA t A 辽宁工程技术大学力学与工程学院俄罗斯科学院西伯利亚分院矿业研究所

当外界扰动频率接近块系岩体的固有频率时，会出现准共振现象。这一现象导致岩块间的弱夹层应变急剧变化，从而加快弱夹层的动态损伤断裂。为了研究块系岩体准共振导致岩块间弱夹层的动态拉压损伤断裂规律，基于块系岩体模型，分析准共... 详细信息

当外界扰动频率接近块系岩体的固有频率时，会出现准共振现象。这一现象导致岩块间的弱夹层应变急剧变化，从而加快弱夹层的动态损伤断裂。为了研究块系岩体准共振导致岩块间弱夹层的动态拉压损伤断裂规律，基于块系岩体模型，分析准共振状态下弱夹层的变形特征。结合岩石动态损伤断裂准则，对准共振状态下弱夹层的动态损伤断裂进行理论计算分析，进而研究动态破坏规律。通过数值模拟揭示了准共振状态下块系岩体中弱夹层的损伤演化特征。结果表明：当块系岩体发生准共振现象时，岩块间的相对位移急剧增加，使得弱夹层的应变和损伤程度明显增大；弱夹层的损伤程度在准共振频率下最高，同时受外部扰动力和弱夹层的刚度、黏性、厚度及岩块质量等系统参数的影响；块系岩体发生准共振时断裂应力增大，但从断裂到完全破坏的时间明显缩短，即残余承载能力大幅下降。该研究对认识块系岩体的动态断裂具有一定的参考价值。

关键词：岩石力学块系岩体准共振弱夹层变形动态损伤断裂

HEAt tRANSFER OF tiO_2/WAtER NANOFLUiD iN A COiLED AGitA-tED vESSEL WitH PROPELLER

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Journal of Hydrodynamics 2012年第6期24卷 942-950页

作者： PERARASU v.t. ARivAZHAGAN M. SivASHANMUGAM P. Heat transfer Research Laboratory Department of Chemical EngineeringNational Institute of Technology

An attempt is made to investigate heat transfer enhancement using nanofluid in a coiled agitated vessel fitted with propeller agitator. the heat transfer coefficient in coiled agitated vessel for water and tiO2/water nanofluid of 3 different volume concentrations （0.10%, 0.20% and 0.30%） are estimated and compared. the heat transfer coefficient for nanofluid is found to be higher than that for water and also found to increase with increasing volume concentrations. the enhancement in the convective heat transfer using nanofluid is found to be a maximum of 17.59%. Empirical correlations are separately formed for water and tiO2/water nanofluid as well as found to fit the experimental data within ±5% for water and within ±10% for nanofluid.

关键词： coiled agitated vessel heat transfer enhancement Nusselt number tiO2/water nanofluid

Semantic Segmentation of Lumbar vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance images

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v v Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril Department of Computer Science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of information technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from t1-weighted mid-sagittal MRi images of 515 patients in the Lumbar Spine MRi Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean intersection over Union(mean ioU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRi) semantic segmentation lumbar vertebrae deep learning U-Net model

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岩石圈的生态作用(英文)

地学前缘 2002年第4期9卷 293-303页

作者： v.t. trofimov Lomonosov Moscow State University

文章确定了“岩石圈的生态作用”这一概念的内涵 ,考虑了作用的分类 ;阐述了岩石圈的各种生态作用 ,它们分别是资源的、地球动力学的、地球化学的和地球物理的生态作用 ;阐明了在地球演化过程中和工程技术造成的影响之下这些生态作用形... 详细信息

文章确定了“岩石圈的生态作用”这一概念的内涵 ,考虑了作用的分类 ;阐述了岩石圈的各种生态作用 ,它们分别是资源的、地球动力学的、地球化学的和地球物理的生态作用 ;阐明了在地球演化过程中和工程技术造成的影响之下这些生态作用形成的规律 ;提出了有关这些生态作用的研究课题。

关键词：生态地质学岩石圈的生态作用岩石圈的资源的、地球动力学的、地球化学的和地球物理的生态作用关于岩石圈生态作用的科学

Fecal microbiota transplantation in allergic diseases

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World Journal of Methodology 2025年第2期15卷 83-91页

作者： Ece tüsüzÖnata ÖnerÖzdemir Division of Pediatric Allergy and immunology Medical FacultySakarya UniversityAdapazarı54100SakaryaTürkiye

Microorganisms such as bacteria,fungi,viruses,parasites living in the human intestine constitute the human intestinal *** refers to composi-tional and quantitative changes that negatively affect healthy gut *** recent years,with the demonstration that many diseases are associated with dysbiosis,treatment strategies targeting the correction of dysbiosis in the treat-ment of these diseases have begun to be *** microbiota trans-plantation(FMt)is the process of transferring faeces from a healthy donor to another recipient in order to restore the gut microbiota and provide a therapeutic *** studies have gained popularity after probiotic,prebiotic,symbiotic studies in the treatment of dysbiosis and related *** has emerged as a potential new therapy in the treatment of allergic diseases as it is associated with the maintenance of intestinal microbiota and immunological balance(t helper 1/t helper 2 cells)and thus suppression of allergic *** this article,the definition,application,safety and use of FMt in allergic diseases will be discussed with current data.

关键词： Microbiota Dysbiosis Faecal microbiota transplantation Allergic diseases

Surgical site soft tissue thickness as a predictor of complications following arthroplasty

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World Journal of Methodology 2025年第2期15卷 62-73页

作者： Kevin A Wu Faheem Pottayil Crystal Jing Ankit Choudhury Albert t Anastasio Department of Orthopaedic Surgery Duke University HospitalDurhamNC 27710United States Department of Orthopaedic Surgery Medical College of Georgia at Augusta UniversityAugustaGA 30912United States Department of Orthopaedic Surgery Medical College of WisconsinMilwaukeeWI 53226United States

Appreciation of soft-tissue thickness(Stt)at surgical sites is an increasingly recognized aspect of arthroplasty procedures as it may potentially impacting postoperative *** research has focused on the predictive value of preoperative Stt measurements for complications following various forms of arthroplasty,particularly infections,across procedures such as total knee,hip,shoulder,and ankle *** studies have indicated that increased Stt is associated with a higher risk of complications,including infection and wound healing *** assessment of Stt before surgery could play a crucial role in identifying patients at a higher risk of complications and may be instru-mental in guiding preoperative planning to optimize outcomes in arthroplasty *** measurement techniques and further research are essential to enhance the reliability and clinical utility of Stt assessment for arthro-plasty surgery.

关键词： Soft-tissue thickness Arthroplasty Surgical complications total knee arthroplasty total hip arthroplasty total shoulder arthroplasty total ankle arthroplasty Preoperative assessment Wound healing infection risk

implementation of a double trigger condition system based on charge comparison and tOF measurement for the NEDA detector array

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Nuclear Science and techniques 2025年第2期36卷 40-48页

作者： J.M.Deltoro A.Goasduff F.J.Egea v.González A.Gadea R.M.Pérez-vidal i.Lazarus M.Kogimtzis L.McNicholl M.Palacz G.Jaworski J.J.valiente-Dobón J.Nyberg S.Casans A.E.Navarro-Antón E.Sanchis A.Boujrad E.Clément t.Hüyük R.illicachi O.Stezowski v.Modamio Department of Electronic Engineering University of ValenciaBurjassotValenciaSpain istituto Nazionale di Fisica Nucleare Laboratori Nazionali di LegnaroLaboratori Nazionali di LegnaroLegnaroPadovaItaly instituto de Física Corpuscular CSIC-Universidad de ValenciaCSIC-Universidad de Valencia46980 PaternaValenciaSpain Science and technology Facilities Council DaresburyUK Heavy ion Laboratory University of Warsaw02-093 WarsawPoland Department of Physics and Astronomy Uppsala UniversityUppsalaSweden Grand Accélérateur National d’ions Lourds(GANiL) CEA/DRF-CNRS/IN2P3CEA/DRF-CNRS/IN2P3CaenFrance Universitéde Lyon UniversitéLyon-1CNRS/IN2P3UMR5822IP2IIP2I4 Rue Enrico Fermi69622 Villeurbanne CedexFrance Department of Physics University of Oslo0316 OsloNorway

the NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitiv.t. of the setup by enabling reaction channel selection through counting of the evaporated *** article presents the implementation of a double trigger condition system for NEDA,which improves the acquisition of neutrons and reduces the number of gamma rays *** independent triggers are generated in the double trigger condition system:one based on charge comparison(CC)and the other on time-of-flight(tOF).these triggers can be combined using OR and AND logic,offering four distinct trigger *** developed firmware is added to the previous one in the virtex 6 field programmable gate array(FPGA)present in the system,which also includes signal processing,baseline correction,and various trigger logic *** performance of the trigger system is evaluated using data from the E703 experiment performed at *** four trigger modes are applied to the same data,and a subsequent offline analysis is *** is shown that most of the detected neutrons are preserved with the AND mode,and the total number of gamma rays is significantly *** with the CC trigger mode,the OR trigger mode allows increasing the selection of *** addition,it is demonstrated that if the OR mode is selected,the online CC trigger threshold can be raised without losing neutrons.

关键词： Neutron detector Neutron-gamma discrimination Pulse shape analysis time-of-flight Charge comparison

Asymptotics for filtration of polydisperse suspension with small impurities

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 109-126页

作者： L.i.KUZMiNA Y.v.OSiPOv.t.N.GORBUNOvA Department of Applied Mathematics National Research University Higher School of EconomicsMoscow 101000Russia Department of Applied Mathematics Moscow State University of Civil Engineering(National Research University)Moscow 129337Russia

A model for deep bed filtration of a polydisperse suspension with small impurities in a porous medium is *** suspended particles move with the same velocity as the carrier water and get blocked in the pore throats due to the size-exclusion mechanism of particle retention.A solution of the model in the form of a traveling wave is *** global exact solution for a multiparticle filtration with one high concentration and several low concentrations of suspended particles is obtained in an explicit *** analytic solutions for a bidisperse suspension with large and small particles are *** profiles of the retained small particles change monotony with *** global asymptotics for the filtration of a polydisperse suspension with small kinetic rates is constructed in the whole filtration zone.

关键词： deep bed filtration suspension colloid porous medium particle size distribution analytical model