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流域可持续水资源管理的模拟和决策支持框架(英文)

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流域可持续水资源管理的模拟和决策支持框架(英文)

Performance analysis of a 2D numerical model in estimating minimum fluidization velocity for fluidized beds

2009水资源与可持续发展高层论坛

作者： ralph parkin Bob Potter David Webb Halcrow China Ltd Shanghai 200083China Halcrow Group Ltd Burderop ParkSwindonSN4 0QDUK

＜正＞Sustainability is a key objective of water resources management and this paper describes a modelling and decision support framework that achieves this,illustrated by applications on the UK Thames and Mekong river basins. The decision support framework contains several modules,including an interactive user’s interface linked to a GIS,a geo-database,knowledge base,simulation models and optimization *** on the analysis of scenarios and proposed interventions, efficient modelling and optimisation tools form a comprehensive integrated decision support framework for the analysis and operational management of water resources in the river basin: our emphasis has been on a practical implementation through careful screening of alternatives, consideration of the institutional framework and direct involvement of stakeholders in the decision making *** in this environment is transparent,reproducible and auditable,securing the trust of all interested *** paper discusses its applications to water utilisation on the Mekong river basin and drought management of the Lower Thames stored reservoir system.

关键词： Decision support framework sustainable water resources management mathematical modelling optimisation

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Particuology 2023年第6期77卷 116-127页

作者： Nazmul Hossain ralph Metcalfe Department of Mechanical Engineering University of HoustonHoustonTX77004USA

The minimum fluidization velocity of a fluid-solid particle fluidized bed is the primary focus of this *** computationally economic Eulerian Granular model has been used to analyze fluidization for both gas-solid particle and liquid-solid particle fluidized *** conventional approach of finding minimum fluidization velocity(umf)is either with a pressure drop across the particle bed or the change in bed ***,these parameters are often unstable and cannot be used to generalize the degree of fluidization *** this paper,the dominant factor of unstable pressure drop estimation in the 2D Two-Fluid Model(TFM)and a key non-dimensional Euler number has been investigated in deter-mining minimum fluidization velocity for different quasi-2D fluidized beds for different bed sizes,par-ticle sizes,and particle *** assumptions and limitations of these numerical models are discussed in detail for four different fluidized bed cases.A comparative study of the drag model shows little to no influence in unstable pressure drop estimation near fluidization velocity,and all drag models perform *** is observed that particle-particle collision is not the dominant reason for unstable pressure drop near minimum ***,wall effects on the particle bed including frictional losses and wall-particle collision play a key role in unstable pressure drop calculation for the quasi-2D fluidized *** drop characteristics alone do not suffice to obtain minimum fluidization ve-locity with 2D TFM using existing ***,a different approach has been proposed to investigate minimum fluidization involving the Euler number,which has shown promising performance in deter-mining minimum fluidization velocity and characterizing fluidization with 2D *** show con-sistency in Euler number characteristics for all different fluidized bed cases considered in this *** can revitalize computationally economic 2D Eulerian simulatio

关键词： Fluidized bed Minimum fluidization velocity Fluid-solid particle flow Eulerian granularmultiphase model

Review of the applications of Multiangle Imaging SpectroRadiometer to air quality research

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Science China Earth Sciences 2009年第1期52卷 132-144页

作者： ralph A.KAHN Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA

The Multiangle Imaging SpectroRadiometer(MISR) launched by NASA in late 1999 has a unique mul-tiangle design,which points nine cameras at fixed angles along the satellite flight track and collects reflected solar radiation *** design allows the retrieval of a rich dataset of particle abundance,shape and composition over both land and *** of its capabilities have not been seen by any currently operating satellite aerosol *** MISR is sensitive to fine particles,it provides a new data source to study the spatial and temporal characteristics of air quality over large geographical *** first briefly introduce the MISR instrument,the retrieval and structure of MISR aerosol data,and then review the applications of MISR aerosol data in various aspects of air quality research since its *** include the spatial distributions of particle pollution events such as dust storms,wild fires,and urban *** of the high quality of MISR aerosol data,they can be used as quantitative indicators of particle pollution *** review the current modeling studies of surface level particle ***,we introduce research results using MISR's advanced data such as the plume heights,and particle microphysical *** the discussion,we compare MISR research with current MODIS research to the best of our ability as MODIS data have been more extensively explored by the Chinese scientific ***,we summarize the advantages and disadvantages of MISR data related to its applications to the air quality *** the highly quantitative measurements and comprehensive aerosol information MISR can provide,we believe that it will provide great values to advance our understanding of the particle air pollution in China.

关键词： aerosol remote sensing MISR multiangle imaging aerosol optical thickness particulate matters PM2.5 PM10 air pollution

Some Open Problems in Parameterized Complexity Related to the Work of Jianer Chen

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Tsinghua Science and Technology 2014年第4期19卷 325-328页

作者： Michael ralph Fellows Engineering and IT Charles Darwin UniversityDarwin 0909 Northern TerritoryAustralia

This short paper highlights some open problems related to the work of Jianer Chen in the area of parameterized/multivariate algorithmics.

关键词： parameterized complexity multivariate algorithmics open problems

Modulation of ice ages via precession and dust-albedo feedbacks

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Geoscience Frontiers 2016年第6期7卷 891-909页

作者： ralph Ellis Michael Palmer 105-6817 Route Pommier St Martin Bellevue 74370France University of Waterloo Department of ChemistryWaterlooOntarioCanada

We present here a simple and novel proposal for the modulation and rhythm of ice-ages and interglacials during the late Pleistocene. While the standard Milankovitch-precession theory fails to explain the long intervals between interglacials, these can be accounted for by a novel forcing and feedback system involving CO2, dust and albedo. During the glacial period, the high albedo of the northern ice sheets drives down global temperatures and CO2 concentrations, despite subsequent precessional forcing maxima. Over the following millennia more CO2 is sequestered in the oceans and atmospheric concentrations eventually reach a critical minima of about 200 ppm, which combined with arid conditions, causes a die-back of temperate and boreal forests and grasslands, especially at high altitude. The ensuing soil erosion generates dust storms, resulting in increased dust deposition and lower albedo on the northern ice sheets. As northern hemisphere insolation increases during the next Milankovitch cycle, the dust-laden ice-sheets absorb considerably more insolation and undergo rapid melting, which forces the climate into an interglacial period. The proposed mechanism is simple, robust, and comprehensive in its scope, and its key elements are well supported by empirical evidence.

关键词： Paleoclimatology Ice-age Precession CO2 Albedo Dust

The Translational Apparatus of Plastids and Its Role in Plant Development

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Molecular Plant 2014年第7期7卷 1105-1120页

作者： Nadine Tiller ralph Bock Max-Planck-Institut for Molekulare Pflanzenphysiologie Am Muhlenberg 1 D-14476 Potsdam-Golm Germany

Chloroplasts （plastids） possess a genome and their own machinery to express it. Translation in plastids occurs on bacterial-type 70S ribosomes utilizing a set of tRNAs that is entirely encoded in the plastid genome. In recent years, the components of the chloroplast translational apparatus have been intensely studied by proteomic approaches and by reverse genetics in the model systems tobacco （plastid-encoded components） and Arabidopsis （nucleus-encoded components）. This work has provided important new insights into the structure, function, and biogenesis of chloroplast ribosomes, and also has shed fresh light on the molecular mechanisms of the translation process in plastids. In addition, mutants affected in plastid translation have yielded strong genetic evidence for chloroplast genes and gene products influencing plant develop- ment at various levels, presumably via retrograde signaling pathway（s）. In this review, we describe recent progress with the functional analysis of components of the chloroplast translational machinery and discuss the currently available evidence that supports a significant impact of plastid translational activity on plant anatomy and morphology.

关键词： plastid translation ribosome ribosomal protein evolution plastid transformation retrograde signaling leaf development palisade cell.

Lexicalized Dependency Paths Based Supervised Learning for Relation Extraction

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Computer Systems Science & Engineering 2022年第12期43卷 861-870页

作者： Huiyu Sun ralph Grishman New York University New York10012USA

Log-linear models and more recently neural network models used forsupervised relation extraction requires substantial amounts of training data andtime, limiting the portability to new relations and domains. To this end, we propose a training representation based on the dependency paths between entities in adependency tree which we call lexicalized dependency paths (LDPs). We showthat this representation is fast, efficient and transparent. We further propose representations utilizing entity types and its subtypes to refine our model and alleviatethe data sparsity problem. We apply lexicalized dependency paths to supervisedlearning using the ACE corpus and show that it can achieve similar performancelevel to other state-of-the-art methods and even surpass them on severalcategories.

关键词： Relation extraction dependency paths lexicalized dependency paths supervised learning rule-based models

A rapid absorbance-based growth assay to screen the toxicity of oligomer Aβ42 and protect against cell death in yeast

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Neural Regeneration Research 2020年第10期15卷 1931-1936页

作者： Prashant Bharadwaj ralph Martins Centre of Excellence for Alzheimer’s Disease Research and Care School of Medical and Health SciencesEdith Cowan UniversityWestern AustraliaAustralia School of Pharmacy and Biomedical Sciences Curtin Health and Innovation Research Institute(CHIRI)Faculty of Health SciencesCurtin UniversityWestern AustraliaAustralia School of Psychiatry and Clinical Neuroscience.University of Western Australia Western AustraliaAustralia School of Biomedical Science Macquarie UniversitySydneyNSWAustralia

Multiple lines of evidence show that soluble oligomer forms of amyloidβprotein(Aβ42)are the most neurotoxic species in the brain and correlates with the degree of neuronal loss and cognitive deficit in Alzheimer’s *** many studies have used mammalian cells to investigate oligomer Aβ42 toxicity,the use of more simple eukaryotic cellular systems offers advantages for large-scale screening *** have previously established and validated budding yeast,Saccharomyces cerevisiae to be a simple and a robust model to study the toxicity of Aβ.Using colony counting based methods,oligomeric Aβ42 was shown to induce dose-dependent cell death in *** have adapted this method for high throughput screening by developing an absorbance-based growth *** further validated the assay with treatments previously shown to protect oligomer Aβ42 induced cell death in mammalian and yeast *** assay offers a platform for studying underlying mechanisms of oligomer Aβ42 induced cell death using gene deletion/overexpression libraries and developing novel agents that alleviate Aβ42 induced cell death.

关键词： Alzheimer’s disease amyloid toxicity autophagy Aβ42 oligomer high-throughput screening latrepirdine neuroprotection yeast model

Evaluation for Small Visual Difference Between Conforming Meshes on Strain Field

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Journal of Computer Science & Technology 2009年第1期24卷 65-75页

作者：边哲胡事民 ralph R.Martin Department of Computer Science and Technology Tsinghua University School of Computer Science Cardiff UniversityCardiffU.K.

This paper gives a method of quantifying small visual differences between 3D mesh models with conforming topology, based on the theory of strain fields. Strain field is a geometric quantity in elasticity which is used to describe the deformation of elastomer. In this paper we consider the 3D models as objects with elasticity. The further demonstrations are provided： the first is intended to give the reader a visual impression of how our measure works in practice; and the second is to give readers a visual impression of how our measure works in evaluating filter algorithms. Our experiments show that our difference estimates are well correlated with human perception of differences. This work has applications in the evaluation of 3D mesh watermarking, 3D mesh compression reconstruction, and 3D mesh filtering.

关键词： 3D conforming meshes mesh comparison perception strain fields