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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 186-196页

作者： Sara Marijan Luka Pavic Division of Materials Chemistry Ruđer Boskovic InstituteBijenicka 54HR-10000 ZagrebCroatia

Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 *** transition from a predominantly phosphate glass network(xhrough modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic *** contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation *** high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)*** scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a

关键词： phosphate glasses glass-ceramics impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism

Mammal-bearing Pleistocene deposits,Vranic,southwestern Pannonian Basin System

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Journal of Palaeogeography 2024年第3期13卷 430-452页

作者： Adriano Banak Zsòfia Ruszkiczay-Rüdiger Anita Grizelj Martina Đuras Kresimir Petrinjak ASTER Team Alexander Wieser Monika Milosevic Davor Pavelic Department of Geology Croatian Geological SurveyMilana Sachsa 2HR-10000 ZagrebCroatia Institute for Geological and Geochemical Research HUN-REN Research Centre for Astronomy and Earth Sciences(MTA Centre of Excellence)Budaorsi Street 451112 BudapestHungary The Faculty of Veterinary Medicine University of ZagrebHeinzelova 55HR-10000 ZagrebCroatia CEREGE CNRS-IRD-College de France-INRAE UM34Aix-Marseille UniversiteAix-en-ProvenceFrance Faculty of Physics-Isotope Physics University of ViennaWahringer Straße 171090 ViennaAustria Faculty of Mining Geology and Petroleum EngineeringUniversity of ZagrebPierottijeva 6HR-10000 ZagrebCroatia

Vranic site is a sand quarry that is located on the southern foothills of Papuk *** bottom to top of the succession,three sedimentary units have been recognized as:Unit 1 containing massive sand with scattered gravel-sized clasts,marl cobbles and boulders,and abundant marine mammal and fish fossils;Unit 2 consisting of sand intercalated with silt,clay and gravel,which may be horizontally bedded;and Unit 3,which is an erosionally-based lenticular matrix to clast-supported structureless *** basal part of Unit 1 shows numerous reworked skeletal remains of Miocene marine *** radionuclides constrain the age of burial of Unit 1 to 895±211 ka,while the source area of Unit 1 had a quick *** massive sands deposited on the slopes of Papuk Mountain were vulnerable to erosion due to the absence of *** rainfall or water from snow melting created flash floods that infiltrated the sands,thereby causing slope destabilization and *** process led to slumps that were transformed into a sandy debris *** sediment was probably deposited during the interglacial marine isotope age(MIS)21 period when the scarce vegetation and a warmer climate favored the melting of permafrost ice and consequently triggered slope movements during MIS *** reworked skeletal material sampled at the Vranic site comprises fossilized fish along with mammal bones and ***,the Vranic site represents an important site for cetacean fossil remains and serves as an important data source for marine life in the Central Paratethys.

关键词： Miocene marine mammals Alluvial slope deposit Pleistocene Cosmogenic nuclides Pannonian Basin System

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蔡雪:AI驱动下重塑hr新生态

企业家 2024年第5期 74-77页

作者：张冰馨蔡雪不详金蝶中国hr产品事业部

在数字化转型的浪潮中,AI与大数据等新兴技术正以前所未有的力量重塑行业格局与职业生态。近日,《企业家》杂志就这一主题采访了资深人力资源专家——金蝶中国hr产品事业部联席总经理蔡雪,共同探讨了在技术革新背景下,AI技术对产品创新... 详细信息

在数字化转型的浪潮中,AI与大数据等新兴技术正以前所未有的力量重塑行业格局与职业生态。近日,《企业家》杂志就这一主题采访了资深人力资源专家——金蝶中国hr产品事业部联席总经理蔡雪,共同探讨了在技术革新背景下,AI技术对产品创新方向和新生态构建的潜在影响,展现了技术进步如何塑造未来人力资源行业的生动图景.

关键词：产品事业部行业格局人力资源专家数字化转型大数据生态构建创新方向 AI技术

Nonlinear Model of Mean Free Surface of Waves

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China Ocean Engineering 1999年第2期14卷 155-162页

作者： Nicholas DODD Ph. D. Coastal Group HR Wallingford Howbery Park Wallingford

A nonlinear model of mean free surface of waves or wave set-up is presented. The model is based on that of Roelvink (1993), but the numerical techniques used in the solution are based on the Weighted-Average Flux (WAF) method (Watson el al., 1992), with Time-Operator-Splitting (TOS) used for the treatment of the source terms. This method allows a small number of computational points to be used, and is particularly efficient in modeling wave set-up. The short wave (or primary wave) energy equation is solved by use of a more traditional Lax-Wendroff technique. A nonlinear wave theory (James, 1974) is introduced. The model described in this paper is found to be satisfactory in most respects when compared with the measurements conducted by Stive (1983) except in modeling the mean free surface very close to the mean shoreline.

关键词： mean free surface radiation stress hyperbolic wave theory nonlinear model wave propagation

Breeding phase and outcome determine space use in European rollers Coracias garrulus prior to migration

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Current Zoology 2024年第2期70卷 137-149页

作者： Flavio Monti Sanja Barisic Sebastian Cannarella Davor Cikovic Vesna Tutis JelenaKralj Carlo Catoni aUniversity of Siena Department of Physical SciencesEarth and EnvironmentVia Mattioli 453100 SienaItaly Institute of Ornithology Croatian Academy of Sciences and ArtsGunduliceva 24HR-1000 ZagrebCroatia Ornis italica Piazza Crati 1500199 RomeItaly

The breeding period is a demanding and time-constrained phase for migratory bird *** outcome and duration can interact with the extent and duration of post-breeding movements,resulting in individual differences in space use ultimately influencing later stages of the annual *** present space-use and home range estimates during the breeding season for 21 European rollers Coracias garrulus tracked between 2018 and 2022,in Italy and *** high-resolution spatial GPS data coupled with regular nest-box monitoring,we analyzed dif-ferences in space use during the incubation/nestling period versus post-breeding period prior to migration,accounting for the breeding outcome(successful ***).We found that adult movements were strongly reduced during the first phase,whereas increased in the post-breeding phase,especially for failed *** breeders remained in the surroundings of the nest site,whereas unsuccessful ones tended to abandon the nest and visit distant areas(up to 500 km)for long periods(60.5±6.2 days).Breeding outcome did not influence the departure date of autumn migration,suggesting that failed breeders used this period for exploratory movements but not for advancing the onset of *** exploratory movements may be functional to prospect and inform settlement decisions in failed breeders in search of new breeding opportunities and may be particularly important in migratory species,which generally have a limited period to gather information prior to autumn *** study demonstrates the need to investigate seasonal movements in different populations and the potential importance of pros-pectingpost-breeding movements for long-distance migratory species.

关键词： animal movement biologging conservation Coracidae Mediterranean nest-box population monitoring prospecting movements reproduction.

Spreadability of powders for additive manufacturing: A critical review of metrics and characterisation methods

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PARTICUOLOGY 2024年第10期93卷 211-234页

作者： Talebi, Fatemeh A. Haydari, Zobaideh Salehi, Hamid Mehrabi, Mozhdeh Gardy, Jabbar Bradley, Mike Bayly, Andrew E. Hassanpour, Ali Univ Leeds Sch Chem & Proc Engn Leeds LS2 9JT England Univ Greenwich Sch Engn Greenwich ME4 4TB England Cormica Ltd Listerhills Sci PkCampus Rd Bradford BD7 1HR England

Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder layers. While extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM systems. This review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability. (c) 2024 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY license (http:// ***/licenses/by/4.0/).

关键词： Powder spreading Powder flowability Powder properties Quality of layer and final products DISCRETE ELEMENT SIMULATION PARTICLE-SIZE DISTRIBUTION SPREADING PROCESS FLOW PROPERTIES NUMERICAL-SIMULATION DENSITY BULK FLOWABILITY SEGREGATION BEHAVIOR

A 3-D numerical study of solitary wave interaction with vertical cylinders using a parallelised particle-in-cell solver

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Journal of Hydrodynamics 2017年第5期29卷 790-799页

作者： Qiang Chen Jun Zang David M.Kelly Aggelos S.Dimakopoulos WEIR Research Unit Department of Architecture and Civil EngineeringUniversity of BathBathUK Coastal Research Laboratory International Hurricane Research CenterFlorida International UniversityMiamiUSA hr wallingford WallingfordOxonUK

This paper aims to provide a better understanding of the interaction between solitary waves and vertical circular cylinders. This is achieved via process based numerical modelling using the parallel particle-in-cell based incompressible flow solver PICIN. The numerical model solves the Navier-Stokes equations for free-surface flows and incorporates a Cartesian cut cell method for fluid-structure interaction. Solitary waves are generated using a piston-type wave paddle. The PICIN model is first validated using a test case that involves solitary wave scattering by a single vertical cylinder. Comparisons between the present results and experimental data show good agreement for the free surface elevations around the cylinder and the horizontal wave force on the cylinder. The model is then employed to investigate solitary wave interaction with a group of eleven vertical cylinders. The wave run-up and wave forces on the cylinders are discussed.

关键词： CFD hybrid Eulerian-Lagrangian particle-in-cell solitary wave vertical cylinder

Experiments on Transformation and Run-Up of Wave Trains

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China Ocean Engineering 2000年第3期15卷 329-337页

作者：董国海李玉成 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China Coastal Group HR Wallingford Howbery Park Wallingford OX10 8BA United Kingdom

This paper. details experiments undertaken in the UK Coastal Research Facility (CRF)at Hy draulies Research (hr), wallingford, on transformation and run-up of wave trains. The purpose of these experiments is to provide verification data for numerical models of wave transformation in shoaling. surf and swash zones. This is the kind of data ih:lt flume experiments are unable to provide, and is collected in the highly controlled environment of CRF where extrinsic factors present in the field are not an issue. The experiments concerning wave trains are undertaken by use of existing wave generation software, and the run-up measurements are made with large experimental run-up gauges.

关键词： experiment transformation wave train run-up random waves regular waves

Modelling of the behavior of marine oil spills: applications based on random walk techniques

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Journal of Environmental Sciences 2000年第1期12卷 3-8页

作者： Li, Zhi-Wei Mead, Christopher T. Zhang, Shu-Shen Dept. of Environ. Sci. and Technol. Dalian University of Technology Dalian 116012 China hr wallingford Howbery Park Wallingford Oxon OX10 8BA United Kingdom

A numerical model has been developed to simulate the transport and fate of oil spilled at sea. The model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under the influence of tidal currents, wind driven currents, and turbulent eddies is simulated by the PLUME RW dispersion model developed by hr wallingford. The weathering processes in the model represent physical and chemical changes of soil slicks with time, and comprise mechanical spreading, dispersion, evaporation and emulsification. Shoreline stranding is determined approximately using a capacity method for different shoreline types. This paper presents details of the model, and describe the results of various sensitivity tests. The model is suitable for oil spill contingency planning.

关键词： oil spill modelling random walk technique CLC number: TQ021 4 Document code: A

A Nonlinear Model of Surf Beat

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China Ocean Engineering 1995年第2期10卷 193-203页

作者： Nicholas Dodd Coastal Group HR WallingfordHowbery RarkWallingford

A nonlinear short-wave-averaged (surf beat) model is presented. The model is based on that of Roelvink (1993), but the numerical techniques used in the solution are based on the so-called weighted-averaged flux (WAF) method (eg Watson et al., 1992), with time-operator splitting used for the treatment of some of the source terms. This method allows a small number of computational points to be used, and is particularly efficient in modelling breaking long waves. The short-wave (or primary-wave) energy equation is solved using a more traditional Lax-Wendroff technique. Results of validation indicate that the model performs satisfactorily in most respects.

关键词： surf beat long wave surf zone