Scale dependence Research Papers - Academia.edu (original) (raw)

Top Papers
Most Cited Papers
Most Downloaded Papers
Newest Papers
People
- by
- •
- Thermodynamics, Atomistic Simulation, Finite Element, Shear bands
- by Sheela Chandra
- •
- Engineering, Technology, Biological Sciences, Tissue culture

The statistics of isotropic homogeneous decaying at moderately large Reynolds number are studied in detail using a Fourier-space band-filtering method on flow fields obtained by direct numerical simulation. Two distinct aspects of the... more

- by Zhen-su She
- •
- Applied Mathematics, Partial Differential Equations, Computer Science, Physics
- by Andreas Wipf
- •
- Quantum Physics, Supersymmetric Models, Fixed Point Theory, High Temperature

ABSTRACT: During the cartographic generalisation process, geographic objects cannot just be considered one by one. The way objects are processed clearly depends on their spatial context. In this paper, we first study the nature of spatial context encountered during map generalisation. We differentiate three kinds of relations that an object ,can have with its environment: being part of a ,significant

- by Bernard Moulin
- •
- Contextual Analysis, Knowledge base, Data Model, Scale dependence
- by David Strong
- •
- Applied Mathematics, Mathematical Physics, Pure Mathematics, Inverse Problems
- by Paul Amand
- •
- Technology, Gene Flow, Seed production, Genetic Engineering
- by Michael Mukolwe
- •
- Food Engineering, Sensory Evaluation, Scale dependence, Food Sciences

The effect of binder properties on torque curves, granule growth kinetics, wet mass consistency and dry granule strength has been investigated in this study. Granulation runs have been performed on a fine cohesive microcrystalline cellulose powder (Avicel 105, d50=20μm) in two types of laboratory high shear mixers: a Mi-Pro high shear mixer using a 1.9L bowl and a 6L Diosna

- by P. Holm
- •
- Mechanical Engineering, Chemical Engineering, Kinetics, Powder technology
- by Bo Engdahl
- •
- Biomedical Engineering, Signal Processing, Decomposition, Optimization
- by Brent Mallinckrodt
- •
- Psychology, Counseling Psychology, Translational Research, Adult attachment
- by Ed Waymire
- •
- Earth Sciences, Ebooks, Biological Sciences, Scale dependence
- by David Dozois
- •
- Pain, Coping Strategies, Treatment Outcome, Adolescent
- by james wilczak
- •
- Mechanical Engineering, Applied Mathematics, Turbulence, Fluid Dynamics
- by William Mackaness
- •
- Cartography, Modeling, Density, Urban And Regional Planning
- by surajit dutta
- •
- Landscape Ecology, Geography, Geology, Geomorphology

Drawing on recent literature on the environmental impact of information and communication technologies (ICTs) and the Internet, this paper identifies three main types of effects: direct impacts of the production and use of ICTs on the environment (resource use and pollution related to the production of infrastructure and devices, electricity consumption of hardware, electronic waste disposal); indirect impacts related to the effect of ICTs on production processes, products and distribution systems (de-materialisation, substitution of information goods for material goods, and substitution of communication at a distance for travel); and structural/behavioural impacts, mainly through the stimulation of structural change and growth in the economy by ICTs, and through impacts on life styles and value systems. This paper argues that the diffusion and use of ICTs are leading to both positive and negative environmental impacts. However, because the effects of ICTs on economic activity are pervasive, their impacts on the environment are difficult to trace and measure. The paper argues for a need to move beyond the dichotomy between pessimism and optimism demonstrated in much of the emerging literature. Instead the relationship must be recognised as complex, interdependent, deeply uncertain and scale-dependent.

- by C. Haberfield
- •
- Civil Engineering, Fractal Geometry, Standard Deviation, Conceptual Model

We investigated the extent of raccoon dog roadkills, and the factors influencing them, using data from the National Expressways in Japan for 1987–1998. A high rate of raccoon dog roadkills occurred in western Japan, whereas a relatively low rate was typical of the central region and of Hokkaido. Kills on the National Expressways increased as traffic and the length of

- by Orlando Ortega
- •
- Geology, Uncertainty Estimation, Fluid flow, Spectrum
- by Lorenzo Lignarolo
- •
- Mechanical Engineering, Civil Engineering, Wind Energy, Turbulence

Intermittent demand appears sporadically, with some time periods showing no demand at all. In this paper, four forecasting methods, Simple Moving Average (SMA, 13 periods), Single Exponential Smoothing (SES), Croston's method, and a new method (based on Croston's approach) recently developed by the authors, are compared on 3000 real intermittent demand data series from the automotive industry. The mean signed and relative geometric root-mean-square errors are shown to meet the theoretical and practical requirements of intermittent demand, as do the Percentage Better and Percentage Best summary statistics based on these measures. These measures are subsequently applied in a simulation experiment. The out-of-sample comparison results indicate superior performance of the new method. In addition, the results show that the mean signed error is not strongly scale dependent and the relative geometric root-mean-square error is a well-behaved accuracy measure for intermittent demand.

- by John E Boylan
- •
- Marketing, Econometrics, Forecasting, Automotive Industry
- by Carlos A Peres
- •
- West Africa, Southeast Asia, Land Use Change, Biological Sciences

An important issue in urban thermal remote sensing is how to use pixel-based measurements of land surface temperature (LST) to characterize and quantify the urban heat island (UHI) observed at the mesoscale and macroscale. Characterization and modeling of UHIs must consider the inherent spatial nonstationarity within land surface variables. This study extended a kernel convolution modeling method for 2-D LST imagery to characterize and model the UHI in Indianapolis, IN, as a Gaussian process. To understand the UHI pattern over space and time, four Advanced Spaceborne Thermal Emission and Reflection Radiometer images of different seasons/years were acquired and analyzed. Furthermore, we employed linear spectral mixture analysis to extract subpixel urban biophysical variables [i.e., green vegetation (GV) and impervious surface (IS)] and developed new indexes of greenness and imperviousness based on the convoluted images of GV and IS fractions. These indexes were proposed to show the contrast in the urban-rural biophysical environmental conditions. Results indicate that the UHI intensity possessed a stronger correlation with both greenness and imperviousness indexes than with GV and IS abundance. Because this study utilized a smoothing kernel to characterize the local variability of urban biophysical parameters, including LST, characterized UHIs can therefore be examined as a scale-dependent process. To this end, we categorized the smoothing parameters into three groups, corresponding to the three scales that are suitable to studying the urban thermal landscape at the microscale, mesoscale, and regional scale, respectively. The identified scales can then be matched with various applications in urban planning and environmental management.

- by Rajib Sarkar
- •
- Geophysics, Remote Sensing, Urban Planning, Pattern Recognition
- by Eva Arnau
- •
- Earth Sciences, Soil Erosion, Spatial Scale, Spatial Pattern
- by Ever Atencia
- •
- Pharmacology, Biochemistry, Bioinformatics, Evolutionary Biology
- by Christiane Eschenbach
- •
- Plant Ecology, Ecology, Community, Multidisciplinary

Estimates of national-scale forest carbon (C) stocks and fluxes are typically based on allometric regression equations developed using dimensional analysis techniques. However, the literature is inconsistent and incomplete with respect to large-scale forest C estimation. We compiled all available diameter-based allometric regression equations for estimating total aboveground and component biomass, defined in dry weight terms, for trees in the United

- by Linda Heath
- •
- Dimensional Analysis, Forest, Global Carbon Cycle, United States
- by Joris de Vente
- •
- Earth Sciences, Arid environments, Land Use Change, Biological Sciences

We present a diagnostic framework to assess changes in flood risk across multiple scales in a river network, under nonstationary conditions or in the absence of historical hydro-meteorological data. The framework combines calibration-free hydrological and hydraulic models with urban development information to demonstrate altered flood risk. Our models utilize hydraulic geometric data and high-resolution remote-sensing information provided on a nearly global basis. The need for calibration is eliminated because model parameters are directly related to the physical properties of the system. We apply the methodology in a case study for Mecklenburg County, NC, in which we assess the effects of land cover changes on flood frequency. We obtained maps of expected inundated zones under different conditions of land cover and storm return periods and compared them with the 100-year return period inundation maps developed by Federal Emergency Management Agency that are based on more complex hydraulic models. The close agreement supports our framework's applicability and generality.

- by Ricardo Mantilla
- •
- Remote Sensing, Flood Risk Management, Risk Analysis, Developing Country
- by Burt Kotler
- •
- Ecology, Predation, Habitat Selection, Predation Risk
- by K. Kok
- •
- Statistical Analysis, Multidisciplinary, Ecological Modelling, Land Use Change
- by Satish Achanta
- •
- Mechanical Engineering, Tribology, Atomic Force Microscopy, Surface topography
- by Joris de Vente
- •
- Soil, Environmental Monitoring, Desertification, Multidisciplinary
- by christobel ferguson
- •
- Risk Management, Risk assessment, Multidisciplinary, Water Supply
- by Guillaume Larocque and +1
- •
- Mathematical Geology, Linear Model, Mean square error, Statistical Properties
- by Elsa Cleland
- •
- Biomass, Productivity, Ecology, Biodiversity
- by Pierre Goovaerts
- •
- Biological Sciences, Environmental Sciences, Stochastic Simulation, Soil Quality
- by Roberto Canullo and +1
- •
- Plant Ecology, Information Theory, Monte Carlo Simulation, Plant Biology

Accurate prediction of rockfalls is a major need in mountain areas, both for hazard assessment and the design of countermeasures. In this paper, the performance of an original simulation code, initially developed for regional-scale analysis, is tested at the local scale by using high-resolution input data, in order to show its application to site-specific problems. The code is based on a kinematic algorithm and allows to run detailed, spatially distributed simulations of rockfall on a three-dimensional topography described by a Digital Elevation Model. Two examples from the Central Italian Alps, both characterised by the occurrence of frequent historical events, valuable elements at risk (urban areas, corridors) and countermeasures (barriers and retaining walls) are presented. The suggested approach proves to effectively account for rockfall dynamics when used with high-resolution data. Model calibration issues are discussed and model results are compared to available experimental data. The scale dependency of the results is also discussed.

- by Giovanni Crosta
- •
- Civil Engineering, Slope Stability, Numerical Modelling, High Resolution
- by Ansarul Karim
- •
- Management, Ecology, Biological Sciences, Environmental Sciences
- by David Labat
- •
- Thermodynamics, Hydrology, Earth, Multidisciplinary
- by Jan Kleissl
- •
- Environmental Engineering, Civil Engineering, Water resources, Large Eddy Simulation

Temporal and spatial scales of disturbance and recovery are often confounded in discussions of landscape equilibrium. We developed a broad framework for the description of landscapes that separates the spatial and temporal scales of disturbance and recovery and predicts the resultant dynamics of a landscape. Two key parameters representing time and space are used to describe potential disturbance dynamics. The temporal parameter, T, is the ratio of the disturbance interval (i.e., time between successive disturbance events) to the time required for a disturbed site to recover to a mature stage. The spatial parameter, S, is the ratio of the size of the disturbance to the size of the landscape. The use of ratios in both parameters permits the comparison of landscapes across a range of spatial and temporal scales. A simple simulation model was developed to explore the implications of various combinations of S and T. For any single simulation, disturbances of a fixed size are imposed at random locations on a gridded landscape at specified intervals. Disturbed sites recover deterministically through succession. Where disturbance interval is long relative to recovery time and a small proportion of the landscape is affected, the system is stable and exhibits low variance over time (e.g., northeastern hardwood forests). These are traditional “equilibrium” systems. Where disturbance interval is comparable to recovery interval and a large proportion of the landscape is affected, the system is stable but exhibits large variance (e.g., subalpine forests in Yellowstone Park). Where disturbance interval becomes much shorter than recovery time and a large proportion of the landscape is affected, the system may become unstable and shift into a different trajectory (e.g., arid ecosystems with altered fire regimes). This framework permits the prediction of disturbance conditions that lead to qualitatively different landscape dynamics and demonstrates the scale-dependent nature of concepts of landscape equilibrium.

- by Yaris Baker
- •
- Landscape Ecology, Earth Sciences, Landscape, Biological Sciences