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Occurrence of an endangered grassland butterfly is mainly driven by habitat heterogeneity,food availability,and microclimate

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Insect Science 2022年第4期29卷 1211-1225页

作者： Gwydion Scherer thomas Fartmann Department of Biodiversity and Landscape Ecology University of OsnabrückOsnabrückGermany Institute of Biodiversity and Landscape Ecology(IBL) MünsterGermany

The Marsh Fritillary(Euphydryas aurinia)was once widespread in large parts of Central ***,in the course of the last century,populations of the butterfly largely ***,we surveyed patch and microhabitat occupancy and its drivers in one of the last vital populations in calcareous *** study revealed that environmental conditions at the landscape and habitat level determined the occurrence of *** in a montane agricultural landscape with low land-use *** occupancy increased with the cover of Devil's-bit Scabious(Succisa pratensis)grasslands in the surroundings of the patches,habitat heterogeneity and host-plant *** occupancy was driven by a warm microclimate and high availability of host *** the well-connected landscape of nutrient-poor grasslands,patch occupancy of *** was driven by parameters defining a high habitat *** heterogeneity very likely buffers *** populations against environmental stochasticity and,hence,enhances long-term *** the gregariously feeding caterpillars of ***,host-plant biomass is *** to their more luxuriant growth,*** plants were clearly preferred,although the Glossy Scabious(Scabiosa lucida)was also ***,the growth of large Succisa plants was favored by soil humidity and grassland *** cope with the adverse macro-and mesoclimatic conditions of the study area,females of the butterfly selected host plants growing in extraordinarily warm microhabitats for *** secure long-term viability of *** populations,we recommend creating mosaics of traditionally managed grasslands and early stages of abandonment within the patches.

关键词： agricultural landscape calcarcous grassland hay meadow host-plant abundance land-use change traditional management

Finite morphisms of projective and K■hler manifolds

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Science China Mathematics 2008年第4期51卷 685-694页

作者： thomas PETERNELL Mathematisches Institut Universit■t Bayreuth

In this paper we study finite morphisms of projective and compact K■hler manifolds, in particular,positivity properties of the associated vector bundle,deformation theory and ramified endomorphisms.

关键词： finite morphism deformation Galois covering ample vector bundle Fano manifold

Paralinearization of the Dirichlet-Neumann operator and applications to progressive gravity waves Dedicated to the NSFC-CNRS Chinese-French summer institute on fluid mechanics in 2010

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Science China Mathematics 2012年第2期55卷 207-220页

作者： ALAZARD thomas DMAet CNRS UMR 8553 Ecole Normale Supdrieure 45 rue d＇Ulm 75005 Paris France

This note presents a paradifferential approach to the analysis of the water waves equations.

关键词： incompressible Euler equation free surface paradifferential calculus

Numerical simulation on inclusion transport in continuous casting mold

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Journal of University of Science and Technology Beijing 2006年第4期13卷 293-300页

作者： Lifeng Zhang Brian G thomas Department of Materials Science ＆ Engineering Norwegian University of Science ＆ Technology （NTNU） Alfred Getz vei 2 N-7491 Trondheim Norway University of Illinois at Urbana-Champaign 1206 W. Green St. Urbana IL 61801 USA

Turbulent flow, the transpor＇t of inclusions and bubbles, and inclusion removal by fluid flow, transport and by bubble flotation in the strand of the continuous slab caster are investigated using computational models, and validated through comparison with plant measurements of inclusions. Steady 3-D flow of steel in the liquid pool in the mold and upper strand is simulated with a finitedifference computational model using the standard k-εturbulence rondel. Trajectories of inclusions and bubhles tire calculated by integrating each local velocity, considering its drag and buoyancy forces, A ＂random walk＂ model is used to incorporate the effect of turbulent fluctuations on the particle motion. The attachment probability of inclusions on a bubble surface is investigated based on fundamental fluid flow simulations, incorporating the turbulent inclusion trajectory and sliding time of each individual inclusion along the bubble surface as a function of particle and bubble size. The chunge in inclusion distribution due to removal by bubble transport in the mold is calculated based on the computed attachment probability of inclusions on each bubble and the computed path length of the bubbles. The results indicate that 6%-10% inclusions are removed by fluid flow transport. 10% by bubble flotation, and 4% by entrapment to the submerged entry nozzle （SEN） walls. Smaller bubbles and larger inclusions have larger attachment probabilities. Smaller bubbles are more efficient for inclusion removal by bubble flotation, so Inng as they are not entrapped in the solidifying shell A larger gas flow rate favors inclusion removal by bubble flotation. The optimum bubble size should be 2-4mm.

关键词： inclusion removal fluid flow transport bubble flotation continuous casting mold attachment probability

Effect of MWCNT reinforcement on the precipitation-hardening behavior of AA2219

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 53-61页

作者： Shijo thomas Umasankar V. School of Mechanical and Building Sciences VIT University

Aluminum alloy matrix composites have found a predominant place in research, and their applications are explored in almost all industries. The aerospace industry has been using precipitation-hardenable alloys in structural applications. However, insufficient literature is available on the influence of multiwalled carbon nanotubes （MWCNTs） on precipitation-hardenable alloy composite materials; thus, this work was designed to elucidate the effect on MWCNT reinforcement on AA2219 with and without precipitation hardening. Reinforcement with MWCNTs has been reported to accelerate precipitation and to achieve greater hardness within a much shorter time. The addition of 0.75wt% MWCNTs resulted in maximal hardness at 90 min, which is approximately 27% of improvement over the maximum hardness achieved by the corresponding monolithic alloy after 10 h of aging. The sample reinforced with 0.75wt% MWCNTs showed an improve- ment of 82% in hardness by solutionizing and aging compared to that achieved by sintering.

关键词： aluminum metal-matrix composites multi walled carbon nanotubes (MWCNT) powder metallurgy heat treatment precipitation hardening

Thermal response of steel framing members in open car park fires

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Frontiers of Structural and Civil Engineering 2022年第9期16卷 1071-1088页

作者： Xia YAN Marion CHARLIER thomas GERNAY Department of Civil and Systems Engineering Johns Hopkins UniversityBaltimoreMD 21218USA ArcelorMittal Steligence Esch-sur-Alzette 4221Luxembourg

For open car park structures,adopting a performance-based structural fire design is often justified and allowed because the fire does not reach ***,this design approach requires an accurate assessment of temperatures in structural members exposed to car *** paper describes a numerical study on the thermal exposure on steel framing members in open car park *** temperatures are computed by the coupling of computational fluid dynamics and finite element modeling,and by analytical models from the *** addition,the influence of galvanization on the steel temperature evolution is *** show that temperatures in unprotected beams and columns are influenced by the section geometry,car fire scenario,modeling approach,and use of *** slightly delays and reduces peak *** the different models,CFD-FEM(CFD:computational fluid dynamics,FEM:finite-element method)coupled models predict lower temperatures than the Hasemi model,because the latter conservatively assumes that the fire flame continuously touches the ***,the Hasemi model cannot account for the effect of reduced emissivity from galvanization on the absorbed heat *** temperature distributions obtained in the steel members can be used to complete efficient structural fire designs based on the member sections,structure layout,and use of galvanization.

关键词： open car park localized fire steel frame numerical modeling computational fluid dynamics

GLOBAL AWARENESS,FUTURE CITY DESIGN AND DECISION MAKING

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Journal of Systems Science and Systems Engineering 2012年第3期21卷 337-355页

作者： thomas L.SAATY Mujgan SAGIR University of Pittsburgh PittsburghPA 15260USA Eskisehir Osmangazi University EskisehirTurkey

Our world has been changing at an exponential rate. As a result of this rapid growth, we will be forced to make changes in not only the way we live in the environment but also in the environment itself such as designing the cities of the future to be in greater harmony with the increasing population and growing complexity. The paper contains both reflections on global awareness and comprehensive criteria and their priorities for choosing the most desirable city.

关键词： Global awareness multicriteria decision making prioritization compact city

Influence of water evaporation on elastohydrodynamic lubrication with water-containing polyalkylene glycols

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Friction 2024年第10期12卷 2370-2388页

作者： Stefan HOFMANN thomas LOHNER Karsten STAHL Technical University of Munich School of Engineering and DesignDepartment of Mechanical EngineeringGear Research Center(FZG)Boltzmannstraße 1585748 Garching near MunichGermany

The reduction of frictional power losses in power transmitting gears takes a crucial role in the design of energy-and resource-efficient ***-containing lubricants like glycerol and polyalkylene glycols have shown great potential in achieving friction within the superlubricity regime with coefficients of friction lower than 0.01 under elastohydrodynamic ***,a bio-based production of the base stocks can lead to the development of green ***,one challenge associated with the application of water-containing lubricants to gearboxes is the evaporation of water and its impact on the lubricant *** this study,the influence of water evaporation on elastohydrodynamic friction and film thickness was investigated for three water-containing polyalkylene *** nominal water contents of 20 wt%and 40 wt%and two viscosities were *** results show that the friction increases continuously with higher evaporated water content,while the overall friction level remains low in nearly water-free states.A similar trend is observed for film thickness,where the strong increase in viscosity results in a notable increase in film ***,the sensitivity of friction and film thickness to water evaporation is low for small amounts of evaporated *** allows generous thresholds for permissible variations in water content.

关键词： friction superlubricity aqueous lubrication elastohydrodynamic lubrication(EHL) evaporation polyalkylene glycol

The embryology of persistent cloaca and urogenital sinus malformations

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Asian Journal of Andrology 2020年第2期22卷 124-128页

作者： David F M thomas University of Leeds LeedsWest Yorkshire LS29JTUK

Cloacal malformations are characterized by the confluence of the lower urinary tract,the female reproductive tract,and the rectum to create a common channel with a single opening on the *** presence of a cloaca is a normal phase of early human embryological *** the 4^th and 7^th weeks of gestation,the cloaca undergoes subdivision to form the hindgut and urogenital *** of this process results in the congenital anomaly termed persistent cloaca(PC).The term urorectal septum malformation sequence(URSMS)is also used to describe this *** classic description of this process which is still cited in many standard textbooks dates from the 19th ***,this has been increasingly called into question by the findings of studies using modern scientific *** sinus anomalies are defined by the confluence of the urethra and vagina to form a common channel of varying length with a single perineal *** this condition,the anorectal canal opens separately on the *** presence of a urogenital sinus represents a transient phase of the normal development of the lower genital tract in the female ***,the form of urogenital sinus most commonly encountered in the developed world is a feature of disordered sexual differentiation and does not arise simply from the persistence of the anatomical structure which is a feature of normal fetal development.

关键词： cloaca embryology urogenital sinus