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  • Least squares calibration of the gravity model when intrazonal flows are unknown
  • The quasi-symmetric side of gravity modelling
  • Calibration ; Entropy maximization ; Flow ; Gravity model ; Markov chain ; Matrix analysis ; Model ; Spatial analysis ; Statistics
  • The A. investigates here quasi-symmetry per se, in contrast to geographical tradition. The size-utility-accessibility parameterization of migration counts turn out to rely exclusively upon the quasi-symmetry of flows. Various facets of quasi
  • different traditions in gravity modelling.
  • Thermal and force-chain effects in an experimental, sloping granular shear flow
  • Experimentation ; Grain size distribution ; Sediment load ; Sediment transport ; Shear stress ; Slope ; Slope gradient ; United States of America
  • Force chains figure prominently in shearing motions of granular materials. A simple scaling of the forces involved in the motion of a dry, gravity driven granular shear flow induced by vibrations suggests that this shearing motion reflects a balance
  • Autoplastic gravity structures in Mecklenburg-Vorpommern (Germany)
  • conditions cryogenesis plays an important role, but the sediment flow and the laterally directed gravitative component associated with bedding and relief conditions must be included in the analysis. According to current observation data from the investigated
  • Submarine channels in Rupert Inlet, British Columbia: II. Sediments and sedimentary structures in Sedimentology of fjords.
  • British Columbia ; Canada ; Cuivre ; Fer ; Fjord ; Fond sous-marin ; Granulométrie ; Gravité spécifique ; Géographie physique ; Littoral ; Plate-forme continentale ; Rupert Inlet ; Structure sédimentaire ; Sédimentologie ; Taux de sédimentation
  • The distributions of sediment properties including grain size, specific gravity and Cu and Fe concentrations for these phases are presented through a succession of three distinct periods or phases over a five years period: meandering channel phase
  • , apron phase and rechannelized phase. Copper-rich, coarse grained deposits were found along channel axes and down the apron flanks. The average thickness of and fraction of the sediment column occupied by turbidities was found to increase with distance
  • down channel, indicating a down channel decrease in the importance of continuous flow to the channel building process.
  • Arizona ; Canyon ; Coastal dynamics ; Current ; Erosion ; Fluvial processes ; Hydraulic works ; Hydrodynamics ; Model ; Sediment transport ; United States
  • The purpose of this paper is to evaluate the relative importance of surface-gravity waves on sandbar stability in Grand Canyon, in contrast to unidirectional currents that are the primary focus of most fluvial studies. A second objective
  • waves are part of the flow field.
  • Derivatives of flows in a doubly constrained gravity model
  • Computation of maximum likelihood estimates of gravity model parameters
  • Algorithm ; Computing ; Distance ; Estimation ; Flow ; Gravity model ; Origin-destination ; Spatial analysis ; Statistics
  • General linear gravity models for the impact of casualty unit closures
  • Accessibility ; Demand ; Emergency services ; England ; Flow ; Gravity model ; Hospital ; London ; Service ; Spatial interaction ; United Kingdom
  • The effects of regionalisation on trade flows
  • Asia ; Economic behaviour ; Economic flow ; Economic integration ; Europe ; Export ; Gravity model ; International trade ; Pacific Region ; Regionalization ; Spatial structure
  • The A. seeks to contextualise spatially the traditional gravity model used widely to examine patterns of international trade. He shows that since global trade is increasingly organised around regions, variations in regionalisation or geographical
  • bias affect the levels of bilateral trade. When such biases are not taken into account, then estimation of the gravity model fails to discriminate between the relative spatial structures of trading regimes. This argument is examined in the context
  • A Bayesian approach to prediction using the gravity model, with an application to patient flow modeling
  • Accessibility ; Demand ; Emergency services ; England ; Facilities ; Flow ; Gravity model ; Hospital ; London ; Simulation ; Spatial analysis ; United Kingdom
  • Allocation of mobile communication flows. From micro-economic demand theory to a gravity model
  • Allocation ; Communication ; Demand ; Gravity model ; Information flow ; Model ; Network ; Spatial analysis ; Telecommunications ; Utility fonction
  • Controlled, ice-cored moraines: sediments and geomorphology. An example from Ragnarbreen, Svalbard
  • Arctic Region ; Cold area ; Debris flow ; Fluvioglacial features ; Front moraine ; Glacial features ; Meltwater ; Polar region ; Sedimentology ; Svalbard
  • in this end moraine complex. However, the intensity of gravity flows is much lower now than it was in the early stages of end moraine complex development. The stability of the ice-cored moraines is due mainly to the thickness of the covering debris, which
  • End moraine of the Ragnarbreen consists of 3 subzones: (1) outer moraine ridge, (2) culmination moraine ridge and (3) inner moraine plateau. Reworking processes were and still are the main factor influencing the morphology and sediment distribution
  • protects the ice from melting. The occurrence of fine sediments on the contemporary hills suggests that the end moraine complex has undergone at least one cycle of topographic inversion. The analysis of landforms and deposits occurring in the end moraine
  • A spatial autoregressive Poisson gravity model
  • Gravity model ; Model ; Monte Carlo analysis ; Origin-destination ; Poisson process ; Regression analysis ; Spatial analysis ; Spatial autocorrelation ; Spatial dependence ; Statistics
  • A Poisson gravity model is introduced that incorporates spatial dependence of the explained variable without relying on restrictive distributional assumptions of the underlying data-generating process. The AA. derive a two-stage nonlinear least
  • be interpreted as the implied total impact effects defined as the sum of direct and indirect spatial feedback effects. The model is illustrated by analyzing patent citation flows data across European regions.
  • Poisson gravity models of spatial flows
  • 1. Tectonics| 2. Sediment isopachs| 3. Crustal structure| 4. Free-air gravity field| 5. Magnetic anomalies| 6. Heat flow, thermal conductivity, thermal gradient. Mercator projection| Scale: 1:6,442,194 at latitude 0| 1,74cm per degree longitude
  • marin ; Quaternaire zones moyennes ; Royaume-Uni ; Sediment gravity flow ; Sédimentologie ; Théorie ; Turbidite à blocs ; verbar; Atlantique
  • Bathymétrie ; Dynamique de versant ; Italie ; Lac ; Lazio ; Modèle numérique de terrain ; Mouvement de masse ; Risque naturel ; Sédiment lacustre
  • Bathymetry ; Digital elevation model ; Italy ; Lacustrine sediment ; Lake ; Lazio ; Mass movement ; Natural hazards ; Slope dynamics
  • , complex rock slides/channelled flows and debris slide and slump. Two main landslide hazard scenarios have been depicted and discussed from the results of the integrated analysis of both subaerial and submerged gravity-induced landforms.
  • depression, and the elucidation of the relationships between subaqueous and subaerial slope processes. The AA. propose a classification based on the landslide's size and type of movement. They recognized rock fall/topples, debris flows, rock slides and slump
  • Effect of saltating sediment on flow resistance and bred roughness in overland flow
  • Carrying capacity ; Experimentation ; Grain size distribution ; Rill wash ; Roughness ; Runoff ; Sediment transport ; Slope
  • This study has evaluated the effect of saltating sediment on flow resistance and bed roughness in overland flow on a fixed sand-covered bed. It is concluded that saltating sediment has a considerable impact on overland flow hydraulics, at least
  • on fixed granular beds. Saltation is likely to have a relatively smaller effect on overland flow on natural hillslopes and agricultural fields where form and wave resistance dominate.
  • Artificial neural networks: a new approach to modeling interregional telecommunication flows
  • Austria ; Gravity model ; Information flow ; Inter-regional trade flow ; Model ; Network ; Regional science ; Telecommunications