Ensemble Modeling. Inference from Small-Scale Properties to Large-Scale Systems.

1985 ◽  
Vol 34 (3) ◽  
pp. 292
Author(s):  
K. Walker ◽  
Alan E. Gelfand ◽  
Crayton C. Walker
Keyword(s):  
Large Scale ◽  
Small Scale ◽  
Ensemble Modeling ◽  
Large Scale Systems ◽  
Scale Properties

scholarly journals Extensive deep neural networks for transferring small scale learning to large scale systems

2019 ◽  
Vol 10 (15) ◽  
pp. 4129-4140 ◽  
Author(s):  
Kyle Mills ◽  
Kevin Ryczko ◽  
Iryna Luchak ◽  
Adam Domurad ◽  
Chris Beeler ◽  
...  
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Large Scale ◽  
Deep Neural Network ◽  
Deep Neural Networks ◽  
Small Scale ◽  
Large Scale Systems ◽  
Energy Entropy ◽  
Large Systems ◽  
Number Of Particles

We present a physically-motivated topology of a deep neural network that can efficiently infer extensive parameters (such as energy, entropy, or number of particles) of arbitrarily large systems, doing so with scaling.

Small water and wastewater systems: pathways to sustainable development?

2004 ◽  
Vol 48 (11-12) ◽  
pp. 7-14 ◽  
Author(s):  
G. Ho
Keyword(s):  
Sustainable Development ◽  
Large Scale ◽  
Small Scale ◽  
Technology Choice ◽  
Large Scale Systems ◽  
Environmentally Sustainable ◽  
Small Water ◽  
Developing Communities ◽  
Wastewater Systems ◽  
Water And Wastewater

Globally we are faced with billions of people without access to safe water and adequate sanitation. These are generally located in developing communities. Even in developed communities the current large scale systems for supplying water, collecting wastewater and treating it are not environmentally sustainable, because it is difficult to close the cycle of water and nutrients. This paper discusses the advantages of small scale water and wastewater systems in overcoming the difficulties in providing water and wastewater systems in developing communities and in achieving sustainability in both developed and developing communities. Particular attention is given to technology and technology choice, even though technology alone does not provide the complete answer. Disadvantages of small scale systems and how they may be overcome are discussed.

scholarly journals Non-local dispersion and the reassessment of Richardson's t3-scaling law

2021 ◽  
Vol 932 ◽  
Author(s):  
G.E. Elsinga ◽  
T. Ishihara ◽  
J.C.R. Hunt
Keyword(s):  
Large Scale ◽  
Scaling Law ◽  
Taylor Dispersion ◽  
Small Time ◽  
Inertial Range ◽  
Small Scale ◽  
Mean Square ◽  
Dispersion Regime ◽  
Non Local ◽  
Scale Properties

The Richardson-scaling law states that the mean square separation of a fluid particle pair grows according to t3 within the inertial range and at intermediate times. The theories predicting this scaling regime assume that the pair separation is within the inertial range and that the dispersion is local, which means that only eddies at the scale of the separation contribute. These assumptions ignore the structural organization of the turbulent flow into large-scale shear layers, where the intense small-scale motions are bounded by the large-scale energetic motions. Therefore, the large scales contribute to the velocity difference across the small-scale structures. It is shown that, indeed, the pair dispersion inside these layers is highly non-local and approaches Taylor dispersion in a way that is fundamentally different from the Richardson-scaling law. Also, the layer's contribution to the overall mean square separation remains significant as the Reynolds number increases. This calls into question the validity of the theoretical assumptions. Moreover, a literature survey reveals that, so far, t3 scaling is not observed for initial separations within the inertial range. We propose that the intermediate pair dispersion regime is a transition region that connects the initial Batchelor- with the final Taylor-dispersion regime. Such a simple interpretation is shown to be consistent with observations and is able to explain why t3 scaling is found only for one specific initial separation outside the inertial range. Moreover, the model incorporates the observed non-local contribution to the dispersion, because it requires only small-time-scale properties and large-scale properties.

scholarly journals A stochastic model for the polygonal tundra based on Poisson-Voronoi Diagrams

2012 ◽  
Vol 3 (1) ◽  
pp. 453-483
Author(s):  
F. Cresto Aleina ◽  
V. Brovkin ◽  
S. Muster ◽  
J. Boike ◽  
L. Kutzbach ◽  
...  
Keyword(s):  
Stochastic Model ◽  
Large Scale ◽  
Climate Models ◽  
Voronoi Diagrams ◽  
Field Studies ◽  
Statistical Characteristics ◽  
Small Scale ◽  
Landscape Response ◽  
Soil Heterogeneities ◽  
Scale Properties

Abstract. Sub-grid processes occur in various ecosystems and landscapes but, because of their small scale, they are not represented or poorly parameterized in climate models. These local heterogeneities are often important or even fundamental for energy and carbon balances. This is especially true for northern peatlands and in particular for the polygonal tundra where methane emissions are strongly influenced by spatial soil heterogeneities. We present a stochastic model for the surface topography of polygonal tundra using Poisson-Voronoi Diagrams and we compare the results with available recent field studies. We analyze seasonal dynamics of water table variations and the landscape response under different scenarios of precipitation income. We upscale methane fluxes by using a simple idealized model for methane emission. Hydraulic interconnectivities and large-scale drainage may also be investigated through percolation properties and thresholds in the Voronoi graph. The model captures the main statistical characteristics of the landscape topography, such as polygon area and surface properties as well as the water balance. This approach enables us to statistically relate large-scale properties of the system taking into account the main small-scale processes within the single polygons.

Overview of Accelerator Applications in Energy

2015 ◽  
Vol 08 ◽  
pp. 1-25 ◽  
Author(s):  
Robert W. Garnett ◽  
Richard L. Sheffield
Keyword(s):  
Large Scale ◽  
Oil And Gas ◽  
High Energy ◽  
Small Scale ◽  
Future Directions ◽  
Industrial Systems ◽  
Large Scale Systems ◽  
Oil And Gas Exploration ◽  
Exploration And Production ◽  
Accelerator Technology

An overview of the application of accelerators and accelerator technology in energy is presented. Applications span a broad range of cost, size, and complexity and include large-scale systems requiring high-power or high-energy accelerators to drive subcritical reactors for energy production or waste transmutation, as well as small-scale industrial systems used to improve oil and gas exploration and production. The enabling accelerator technologies will also be reviewed and future directions discussed.

scholarly journals Large Landholdings in Brabant: Unravelling Urbanization Processes in the City-Territory

2020 ◽  
Vol 5 (2) ◽  
pp. 116-131
Author(s):  
Guillaume Vanneste
Keyword(s):  
Large Scale ◽  
18Th Century ◽  
Small Scale ◽  
Urban Transformations ◽  
The Subject ◽  
Scale Properties ◽  
Ecological Relations ◽  
The Village ◽  
The City ◽  
Fragmentation Processes

Through the observation of land property (le foncier) and, specifically, large landholdings, this research aims to take a fresh look at urbanization and urban planning in the Belgian Walloon Brabant Province. In contrast with most Belgian urban studies that tackle the issue of sprawling urbanization through small-scale parcels, fragmentation processes and individual initiatives, this investigation complements recent research on estate urbanization by examining large-scale properties and how they played a role in the city-territory’s urbanization during the second half of the 20th century. Large landholdings in Walloon Brabant are remnants of 18th century territorial dominions inherited from nobility and clergy, progressively dismantled, reorganized or maintained as result of the urbanization dynamics integral to the reproduction of modern and contemporary society. The village of Rixensart is the subject of a series of these transformations. By mapping the de Merode family’s large landholdings in the south of the commune and analyzing the allotments permit, we retrace urban transformations and the reordering of social and ecological relations through changing land structure. The palimpsest notion is used as a tool to unravel the set of actors involved in urbanization dynamics and to highlight the socio-spatial transformations and construction of recent urbanization. The profound transformations taking place in Walloon Brabant today present an opportunity to reflect on its future, and questions regarding landed estates suggest potential for tackling the city-territory’s greater systemic challenges.

scholarly journals A Method to Estimate the 3D–Time Structure of the Raindrop Size Distribution Using Radar and Disdrometer Data*

2015 ◽  
Vol 16 (3) ◽  
pp. 1222-1242 ◽  
Author(s):  
Marc Schleiss ◽  
James Smith
Keyword(s):  
Size Distribution ◽  
Large Scale ◽  
Space Time ◽  
Radar Reflectivity ◽  
Time Structure ◽  
Small Scale ◽  
Drop Diameter ◽  
Rain Event ◽  
Spatial Anisotropy ◽  
Scale Properties

Abstract A geostatistical method to quantify the small-scale 3D–time structure of the drop size distribution (DSD) from the ground level up to the melting layer using radar and disdrometer data is presented. First, 3D–time radar reflectivity fields are used to estimate the large-scale properties of a rain event, such as the apparent motion, spatial anisotropy, and temporal innovation. The retrieved quantities are then combined with independent disdrometer time series to estimate the 3D–time variogram of each DSD parameter. A key point in the procedure is the use of a new metric for measuring distances in moving anisotropic rainfall fields. This metric has the property of being invariant with respect to the specific rainfall parameter being considered, that is, it is identical for the radar reflectivity, rain rate, mean drop diameter, drop concentration, or any other weighted moment of the DSD. Evidence is shown of this fact and some illustrations for a stratiform event in southern France and a convective case in the midwestern United States are provided. The proposed framework offers a series of new and interesting applications, including the possibility to compare the space–time structure of different rain events, to interpolate radar reflectivity fields in space–time and to simulate 3D–time DSD fields at high spatial and temporal resolutions.

scholarly journals Spatial Contrast of Geographically Induced Rainfall Observed by TRMM PR

2017 ◽  
Vol 30 (11) ◽  
pp. 4165-4184 ◽  
Author(s):  
Masafumi Hirose ◽  
Yukari N. Takayabu ◽  
Atsushi Hamada ◽  
Shoichi Shige ◽  
Munehisa K. Yamamoto
Keyword(s):  
Large Scale ◽  
Tropical Rainfall Measuring Mission ◽  
Small Scale ◽  
Small Islands ◽  
Large Scale Systems ◽  
Medium Scale ◽  
Orographic Rainfall ◽  
Hourly Data ◽  
High Concentrations ◽  
The Tropics

Abstract In this study, the spatial variability in precipitation at a 0.1° scale is investigated using long-term data from the Tropical Rainfall Measuring Mission Precipitation Radar. Marked regional heterogeneities emerged for orographic rainfall on characteristic scales of tens of kilometers, high concentrations of small-scale systems (<10 km) over alpine areas, and sharp declines around mountain summits. In detecting microclimates, an additional concern is suspicious echoes observed around certain geographical areas with relatively low rainfall. A finescale land–river contrast can be extracted in the diurnal behavior of rainfall in medium-scale systems (10–100 km), corresponding to the course of the Amazon River. In addition, rainfall enhancement over small islands (0.1°–1°) was identified in terms of the storm scale. Even 0.1°-scale flat islands experience more rainfall than the adjacent ocean, primarily as a result of localized small or moderate systems. By contrast, compared with small islands, high-impact large-scale systems (>100 km) result in more rainfall over the adjacent ocean. Finescale hourly data represented the abrupt asymmetric fluctuation in rainfall across the coastline in the tropics and subtropics (30°S–30°N). Significant diurnal modulations in the rainfall due to large-scale systems are found over tropical offshore regions of vast landmasses but not over small islands or in the midlatitudes between 30° and 36°. Rainfall enhancement over small tropical islands is generated by abundant afternoon rainfall, which results from medium-scale storms that are regulated by the island size and inactivity of rainfall over coastal waters.

Sign in / Sign up

Export Citation Format

Share Document