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董事会 2014年第12期 92-94页

作者： christopher b.bingham Nathan R.Furr Kathleen M.Eisenhardt

一旦他们看准并研究透彻了特定市场上的机遇,就会制定一套聚焦战略,将注意力牢牢锚定他们认为最佳的机会,这会让战略家们一次性收获一个领域的多个机遇。

关键词：营销创意聚焦战略特定市场锚定执行阶段时间精力销售能力选择方式提供商成功概率

A robust WENO scheme for nonlinear waves in a moving reference frame

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Journal of Hydrodynamics 2016年第3期28卷 482-488页

作者： Stavros KONTOS Harry b.bingham Ole LINDbERG Allan P.ENGSIG-KARUP Department of Mechanical Engineering Technical University of DenmarkDenmark Department of Applied Mathematics and Computer Science Technical University of DenmarkDenmark

For robust nonlinear wave simulation in a moving reference frame, we recast the free surface problem in Hamilton-Jacobi form and propose a Weighted Essentially Non-Oscillatory （WENO） scheme to automatically handle the upwinding of the convective term. A new automatic procedure for deriving the linear WENO weights based on a Taylor series expansion is introduced. A simplified smoothness indicator is proposed and is shown to perform well. The scheme is combined with high-order explicit Runge-Kutta time integration and a dissipative Lax-Friedrichs-type flux to solve for nonlinear wave propagation in a moving frame of reference. The WENO scheme is robust and less dissipative than the equivalent order upwind-biased finite difference scheme for all ratios of frame of reference to wave propagation speed tested. This provides the basis for solving general nonlinear wave-structure interaction problems at forward speed.

关键词： nonlinear waves Weighted Essentially Non-Oscillatory (WENO) finite difference

基于势流理论和OpenFOAM的耦合模型对多向不规则波浪的模拟

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水科学进展 2016年第1期27卷 88-99页

作者：季新然柳淑学 bo T.PAULSEN Harry b.bingham 大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 丹麦技术大学机械学院代尔夫特三角洲研究中心

基于势流理论的数值水池可以快速计算波浪的传播及其对建筑物的作用,但是势流理论是基于波浪的无黏性假设的,而在工程中,通常需要在固体边界及波浪破碎的区域考虑黏性效应。针对基于求解Navier-Stokes方程的黏性水池计算量较大、速度较... 详细信息

基于势流理论的数值水池可以快速计算波浪的传播及其对建筑物的作用,但是势流理论是基于波浪的无黏性假设的,而在工程中,通常需要在固体边界及波浪破碎的区域考虑黏性效应。针对基于求解Navier-Stokes方程的黏性水池计算量较大、速度较慢的缺点,采用耦合的方法模拟多向不规则波浪的传播,即在外域通过基于势流理论的数值水池产生多向不规则波浪,内域采用求解Navier-Stokes方程和流体体积法(VOF方法)对自由表面进行追踪,通过外域所提供的边界波浪,内域计算可以在较小区域进行计算,从而达到减少计算量、提高计算效率的目的。

关键词：势流理论 OpenFOAM 耦合多向不规则波浪

A Numerical Investigation of Gap and Shape Effects on a 2D Plunger-Type Wave Maker

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Journal of Marine Science and Application 2020年第1期19卷 101-115页

作者： Amir H.Nikseresht Harry b.bingham Department of Mechanical Engineering Technical University of DenmarkDK-2800 Kgs LyngbyDenmark Department of Mechanical Engineering Shiraz University of TechnologyShiraz 71555-13876Iran

The installation of plunger-type wave makers in experimental tanks will generally include a gap between the back of the wedge and the wall of the *** this study,we analyze the influence of this gap on the wave making performance of the plunger using two-dimensional(2 D)CFD calculations for a range of nearly linear wave conditions and compare the results with both experimental measurements and linear potential flow *** wedge-shaped profiles,all with the same submerged volume,are ***,the generated waves are compared with the predictions of linear potential flow *** calculations are made using the commercial ANSYS FLUENT finite-volume code with dynamic meshes to solve the Navier-Stokes equations and the volume of fluid scheme to capture the air-water ***,the linear potential flow solution of Wu(J Hydraul Res 26:481-493,1988)is extended to consider an arbitrary profile and serve as a reference *** amplitude ratios of the generated waves predicted by the CFD calculations compare well with the predictions of linear potential flow theory for a simple wedge,indicating that viscous effects do not influence this ratio for small-amplitude motions in 2 *** contrast,significant higher harmonic components are produced by larger amplitude ***,the simple wedge is found to produce the smallest spurious higher harmonic content in the far-field wave.

关键词： Wave maker Plunger-type berkeley wedge Hyperbolic sine profile Gap Dynamic mesh Volume of fluid

Comparative analysis of empirical and deep learning models for ionospheric sporadic E layer prediction

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Earth and Planetary Physics 2025年第1期9卷 10-19页

作者： bingKun Yu PengHao Tian XiangHui Xue christopher JScott HaiLun Ye JianFei Wu Wen Yi TingDi Chen XianKang Dou Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230088China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China Department of Meteorology University of ReadingReading RG66BBUK

Sporadic E(Es)layers in the ionosphere are characterized by intense plasma irregularities in the E region at altitudes of 90-130 *** they can significantly influence radio communications and navigation systems,accurate forecasting of Es layers is crucial for ensuring the precision and dependability of navigation satellite *** this study,we present Es predictions made by an empirical model and by a deep learning model,and analyze their differences comprehensively by comparing the model predictions to satellite RO measurements and ground-based ionosonde *** deep learning model exhibited significantly better performance,as indicated by its high coefficient of correlation(r=0.87)with RO observations and predictions,than did the empirical model(r=0.53).This study highlights the importance of integrating artificial intelligence technology into ionosphere modelling generally,and into predicting Es layer occurrences and characteristics,in particular.

关键词： ionospheric sporadic E layer radio occultation ionosondes numerical model deep learning model artificial intelligence

Signals and noise in the octavolateralis systems: What is the impact of human activities on fish sensory function?

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Integrative Zoology 2015年第1期10卷 4-14页

作者： christopher b.bRAUN Department of Psychology Hunter CollegeCity University of New YorkNew YorkNYUSA

The octavolateralis systems of fishes include the vestibular,auditory,lateral line and electrosensory *** are united by common developmental and neuro-computational features,including hair cell sensors and computations based on cross-neuron analyses of differential hair cell stimulation *** systems also all use both spectral and temporal filters to separate signals from each other and from noise,and the distributed senses(lateral line and electroreception)add spatial filters as *** all sensory systems,these sensors must provide the animal with guidance for adaptive behavior within a sensory scene composed of multiple stimuli and varying levels of ambient noise,including that created by human *** the extreme,anthropogenic activities impact the octavolateralis systems by destroying or degrading the habitats that provide ecological resources and sensory *** slightly lesser levels of effect,anthropogenic pollutants can be damaging to fish tissues,with sensory organs often the most *** exposed sensory cells of the lateral line and electrosensory systems are especially sensitive to aquatic *** still lesser levels of impact,anthropogenic activities can act as both acute and chronic stressors,activating hormonal changes that may affect behavioral and sensory ***,human activities are now a nearly ubiquitous presence in aquatic habitats,often with no obvious effects on the animals exposed to *** noise,indigenous and industrial fishing techniques,and all the ancillary noises of human civilization form a major part of the soundscape of *** fish use these new sources of information about their habitat is a new and burgeoning field of study.

关键词： audition,electrosense lateral line soundscape underwater noise

Hollow ion atomic structure and X-ray emission in dense hot plasmas

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Matter and Radiation at Extremes 2024年第6期9卷 43-52页

作者： Frank b.Rosmej christopher J.Fontes Sorbonne University Faculty of Science and EngineeringUMR 7605Case 1284 Place JussieuF-75252 ParisFrance Ecole Polytechnique LULIAtomic Physics in Dense PlasmasRoute de SaclayF-91129 PalaiseauFrance Computational Physics Division Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA

Hollow ion X-ray emission is of great interest in high-energy-density research,since negligible opacity allows studies from the interior of very dense *** this paper,ionization potential depressions of the isoelectronic sequences for single and double K-shell vacancies are obtained from a pure ab initio multiconfiguration Hartree-Fock simulation including exact exchange terms and finite temperature dense plasma *** is demonstrated that the simultaneous representation of these ab initio data in the form of a map of hollow ion X-ray transition energies enables identification of important steps in the matter evolution and ionization *** along the isoelectronic sequence as a function of the pumping energy of a X-ray free electron laser also enables visualization of the impact of ionization potential depression on the pathways of hollow ion formation.

关键词： enable interior steps

SARS-CoV-2:the many pros of targeting PLpro

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Signal Transduction and Targeted Therapy 2020年第1期5卷 633-634页

作者： christopher b.McClain Nicolas Vabret Department of Medicine Hematology and Medical OncologyIcahn School of Medicine at Mount SinaiNew YorkNYUSA Precision Immunology Institute Icahn School of Medicine at Mount SinaiNew YorkNYUSA

A new study1 published in Nature compares the mechanisms used by SARS-CoV-1 and SARS-CoV-2 papain-like protease(PLpro)to promote innate immune *** findings identify SARS-CoV-2 PLpro as an attractive drug target for tr... 详细信息

关键词： attractive finding Nature

In the forest vine Smilax rotundifolia,fungal epiphytes show site-wide spatial correlation,while endophytes show evidence of niche partitioning

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Fungal Diversity 2015年第6期75卷 279-297页

作者： christopher b.Zambell James F.White Graduate Program in Ecology&Evolution Rutgers UniversityNew BrunswickNJ 08901USA Department of Plant biology&Pathology 59 Dudley RoadNew BrunswickNJ 08901USA

Endophytic and epiphytic fungal assemblages from stems of ***,a shrubby vine,were studied in order to(1)quantify differences and the degree of overlap between fungal communities of both micro-habitats,and(2)examine whether fungal assemblages are spatially correlated at the local scale(tens to hundreds of meters),in order to understand if dispersal limitation may play a role in structuring these *** was conducted over 160 m of growth along a forest *** communities showed low overlap(bray-Curtis Similarity=0.22),with most species that were common in one habitat appearing rarely if at all in the other,and only Aureobasidium pullulans showing high frequency in *** assemblages proved to be spatially correlated along the 160 m length of the transect,and even more so when adjacent pairs of stems were considered as the unit of comparison rather than individual *** assemblages showed no significant spatial correlation along the ***,three species of endophytes showed a pattern in which abundance of colonies peaked at different heights on the *** boninense showed peak abundance at 3 cm from the stem *** sp.1 peaked at 33 cm from the stem *** isolates of *** peaked at 63 cm from the stem *** was also found that positive correlative relationships were detected between endophyte-endophyte,and epiphyte-epiphyte ***-group interactions seemed to center around crossover species that were not entirely constrained within the surface or interior.

关键词： Colletotrichum Phomopsis Phyllosticta Local dispersal Tissue preference

Strategies towards robust interpretations of in situ zircon oxygen isotopes

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Geoscience Frontiers 2023年第2期14卷 241-255页

作者： Janne Liebmann christopher L.Kirkland John b.Cliff christopher J.Spencer Aaron J.Cavosie Timescales of Mineral Systems Group The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin UniversityPerthAustralia Pacific Northwest National Laboratory RichlandWashington 99354United States Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonONCanada Space Science and Technology Centre The Institute for Geoscience Research(TIGeR)School of Earth and Planetary ScienceCurtin UniversityPerthAustralia

Oxygen isotopes are a versatile tool to address a wide range of questions in the Earth *** include geothermometry,paleoclimatology,tracing of geochemical reservoirs,fluid-rock interaction,magmatic petrogenesis,and identification of extra-terrestrial *** arguably provides one of the most robust records of primary magmatic O isotope ratio due to low diffusion rates in crystalline *** ability to correlate zircon O isotopes with temporal and petrogenetic information(e.g.U-Pb geochronology,Lu-Hf isotopes,and trace elements)makes this mineral a key archive for understanding Earth’s crustal ***,zircon O isotope geochemistry has found widespread usage to address fundamental questions across the earth and planetary *** general apparent ease of O isotopic acquisition through the advancement of rapid in situ techniques(*** ion mass spectrometry;SIMS)and associated dedicated national laboratories has led to the generation of large O isotopic data sets of variable quality,highlighting the importance of a coherent workflow for data collection,reduction,and *** paper presents a set of approaches for measurement,assessment,and reporting of zircon O isotope *** focus in this contribution is on in situ analysis via secondary ion mass spectrometry using large geometry instruments,but other commonly used techniques are briefly reviewed for *** work aims to provide an analytical framework necessary for geologically meaningful interpretation of O isotope *** addition,we describe inherent geological(***-induced disturbance of the zircon O isotopic system)and analytical(*** due to sample topography effects)challenges and outline means to identify and avoid such issues as a prerequisite to the generation of robust primary O isotopic signatures for geological interpretation.

关键词： In situ Oxygen isotopes Zircon SIMS Secondary ion mass spectrometry Off-mount standard