San Joaquin-Tulare Conjunctive Use Model: Detailed model description

AbstractVariational Autoencoders (VAEs) are powerful generative models that merge elements from statistics and information theory with the flexibility offered by deep neural networks to efficiently solve the generation problem for high-dimensional data. The key insight of VAEs is to learn the latent distribution of data in such a way that new meaningful samples can be generated from it. This approach led to tremendous research and variations in the architectural design of VAEs, nourishing the recent field of research known as unsupervised representation learning. In this article, we provide a comparative evaluation of some of the most successful, recent variations of VAEs. We particularly focus the analysis on the energetic efficiency of the different models, in the spirit of the so-called Green AI, aiming both to reduce the carbon footprint and the financial cost of generative techniques. For each architecture, we provide its mathematical formulation, the ideas underlying its design, a detailed model description, a running implementation and quantitative results.

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The dependences of the surface plasmon frequencies on the supported metal particle sizes and shapes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125580 ◽

1987 ◽

Vol 45 ◽

pp. 130-131

Author(s):

Z.L. Wang ◽

J.M. Cowley

Keyword(s):

Surface Plasmon ◽

Metal Particle ◽

Experimental Studies ◽

Spherical Particles ◽

Model Description ◽

Particle Sizes ◽

Detailed Model ◽

Particle Properties ◽

Dispersion Effects ◽

Effect Of The Support

I. Theoretical and experimental studies of supported spherical metal particles show that the existence of the support introduce some new surface plasmon modes. As a continuation of our previous work, hydrodynamics theory is used to calculate the plasmon frequencies of the half-embedded spherical particles as a function of the particle sizes. In this study, the spatial dispersion effects of the particle sizes are illustrated. The predicted surface plasmons ⍵h and ⍵LO, as in Fig. 1(A), and ⍵1 to ⍵4 as in Fig. 1(B) are for the cases of a metal A1 particle covered with thin Al2O3 layer sitting on (A) a dielectric insulator AlF3 and (B) a metallic AI plate, respectively. The detailed model description is given in, The dotted solid curves in Fig. 1 are plots of the surface plasmon frequencies for an isolated metal particle. It is clearly seen that the appearance of ⍵LO and ⍵1, ⍵2, and ⍵4, for the two different supporting cases, are due to the existence of the support. It shows that the effect of the support on the metal particle properties must be considered in the practical experiments.

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MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): an aerosol microphysical module for global atmospheric models

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-6003-2008 ◽

2008 ◽

Vol 8 (20) ◽

pp. 6003-6035 ◽

Cited By ~ 128

Author(s):

S. E. Bauer ◽

D. L. Wright ◽

D. Koch ◽

E. R. Lewis ◽

R. McGraw ◽

...

Keyword(s):

Particle Size ◽

Climate Model ◽

Particle Diameter ◽

Number Concentration ◽

Sea Salt ◽

Box Model ◽

Model Description ◽

Mixing State ◽

Cloud Drop ◽

Detailed Model

Abstract. A new aerosol microphysical module MATRIX, the Multiconfiguration Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS) climate model (ModelE) are described. This module, which is based on the quadrature method of moments (QMOM), represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol population, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble aerosol populations. A detailed model description and results of box-model simulations of various aerosol population configurations are presented. The box model experiments demonstrate the dependence of cloud activating aerosol number concentration on the aerosol population configuration; comparisons to sectional models are quite favorable. MATRIX is incorporated into the GISS climate model and simulations are carried out primarily to assess its performance/efficiency for global-scale atmospheric model application. Simulation results were compared with aircraft and station measurements of aerosol mass and number concentration and particle size to assess the ability of the new method to yield data suitable for such comparison. The model accurately captures the observed size distributions in the Aitken and accumulation modes up to particle diameter 1 μm, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment. This is more likely due to oversimplifications of the representation of sea salt emissions – sea salt emissions are only calculated for two size classes – than to inherent limitations of MATRIX.

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Performance Analysis of Solid Oxide Fuel Cell Stack: Part 1 — Model Description and Validation

Volume 6: Energy Systems: Analysis, Thermodynamics and Sustainability ◽

10.1115/imece2007-43627 ◽

2007 ◽

Author(s):

Vittorio Verda ◽

Michele Cali`

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Solid Oxide ◽

Model Description ◽

Current Transfer ◽

Oxide Fuel ◽

Cfd Model ◽

Detailed Model ◽

Fuel Cell Stack ◽

Stack Model

In this paper a detailed model for the simulation of a tubular solid oxide fuel cell stack is presented. The model solves heat transfer, current transfer and fluid flow in the stack. The effect of mass transfer is accounted by means of the information provided by a CFD model of a single cell. The approach used to build the model allows one to simulate large stacks, predicting the temperature, current and mass flow rate profiles. The model has been applied to the CHP100 manufactured by Siemens. The results obtained by the stack model are compared with some of the available measurements.

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A Real-Time Open Access Platform towards Proof of Concept for Smart Grid Applications

Journal of Mobile Multimedia ◽

10.13052/550-4646.1413 ◽

2018 ◽

Author(s):

Mohammed Kemal1 ◽

Lennart Petersen ◽

Florin Iov ◽

Rasmus Løvenstein Olsen

Keyword(s):

Open Access ◽

Smart Grid ◽

Real Time ◽

Model Description ◽

Proof Of Concept ◽

Detailed Model ◽

Power Sources ◽

Electrical Grid ◽

Grid Applications ◽

Set Up

This paper presents development of real time open access platform towards proof of concept of smart grid applications deployed at Smart Energy System Laboratory of Aalborg University. Discussed on the paper is the architecture and set-up of the platform by elaborating the three main layers: electrical grid layer, ICT & network emulation layer and control layer. DiSC-OPAL, a toolbox built for OPAL-RT real time grid simulation; comprising of models for wide variety of controllable flexible assets, stochastic power sources for wind and solar power plants, real consumption data’s and electrical grid components is presented. A detailed model description of the whole set up and the corresponding functionalities is characterized. To showcase real life application of the whole framework, an overview of two test cases implemented for European SmartC2Net project with focus on control and market integration of low voltage distribution grids is presented.

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MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): an aerosol microphysical module for global atmospheric models

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-8-9931-2008 ◽

2008 ◽

Vol 8 (3) ◽

pp. 9931-10003 ◽

Cited By ~ 1

Author(s):

S. E. Bauer ◽

D. Wright ◽

D. Koch ◽

E. R. Lewis ◽

R. McGraw ◽

...

Keyword(s):

Particle Size ◽

Climate Model ◽

Particle Diameter ◽

Global Scale ◽

Number Concentration ◽

Model Description ◽

Carbonaceous Aerosols ◽

Mixing State ◽

Cloud Drop ◽

Detailed Model

Abstract. A new aerosol microphysical module MATRIX, the Multiconfiguation Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS) climate model (ModelE) is described. This module, which is based on the quadrature method of moments (QMOM), represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol mode, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble modes. A detailed model description and results of box-model simulations of various mode configurations are presented. The number concentration of aerosol particles activated to cloud drops depends on the mode configuration. Simulations on the global scale with the GISS climate model are evaluated against aircraft and station measurements of aerosol mass and number concentration and particle size. The model accurately captures the observed size distributions in the aitken and accumulation modes up to particle diameter 1 μm, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment.

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The biophysics, ecology, and biogeochemistry of functionally diverse, vertically- and horizontally-heterogeneous ecosystems: the Ecosystem Demography Model, version 2.2 — Part 1: Model description

10.5194/gmd-2019-45 ◽

2019 ◽

Author(s):

Marcos Longo ◽

Ryan G. Knox ◽

David M. Medvigy ◽

Naomi M. Levine ◽

Michael C. Dietze ◽

...

Keyword(s):

Terrestrial Ecosystems ◽

Companion Paper ◽

Model Description ◽

Ecosystem Structure ◽

Detailed Model ◽

Carbon Cycles ◽

Model Version ◽

Vertical Heterogeneity ◽

Individual Trees ◽

Functionally Diverse

Abstract. Earth System Models (ESMs) have been developed to represent the role of terrestrial ecosystems on the energy, water, and carbon cycles. However, many ESMs still lack representation of within-ecosystem heterogeneity and diversity. In this manuscript, we present the Ecosystem Demography Model version 2.2 (ED-2.2). In ED-2.2, the biophysical and physiological cycles account for the horizontal and vertical heterogeneity of the ecosystem: the energy, water, and carbon cycles are solved separately for each group of individual trees of similar size and functional group (cohorts) living in a micro-environment with similar disturbance history (patches). We define the equations that describe the energy, water, and carbon cycles in terms of total energy, water, and carbon, which simplifies the ordinary differential equations and guarantees excellent conservation of these quantities in long-term simulation ( < 0.1 % error over 50 years). We also show examples of ED-2.2 simulation results at single sites and across tropical South America. These results demonstrate the model's ability to characterize the variability of ecosystem structure, composition and functioning both at stand- and continental-scales. In addition, a detailed model evaluation was carried out and presented in a companion paper. Finally, we highlight some of the ongoing developments in ED-2.2 that aim at reducing the uncertainties identified in this study and the inclusion of processes hitherto not represented in the model.

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The biophysics, ecology, and biogeochemistry of functionally diverse, vertically and horizontally heterogeneous ecosystems: the Ecosystem Demography model, version 2.2 – Part 1: Model description

Geoscientific Model Development ◽

10.5194/gmd-12-4309-2019 ◽

2019 ◽

Vol 12 (10) ◽

pp. 4309-4346 ◽

Cited By ~ 14

Author(s):

Marcos Longo ◽

Ryan G. Knox ◽

David M. Medvigy ◽

Naomi M. Levine ◽

Michael C. Dietze ◽

...

Keyword(s):

Terrestrial Ecosystems ◽

Companion Paper ◽

Model Description ◽

Ecosystem Structure ◽

Detailed Model ◽

Carbon Cycles ◽

Model Version ◽

Physiological Processes ◽

Vertical Heterogeneity ◽

And Performance

Abstract. Earth system models (ESMs) have been developed to represent the role of terrestrial ecosystems on the energy, water, and carbon cycles. However, many ESMs still lack representation of within-ecosystem heterogeneity and diversity. In this paper, we present the Ecosystem Demography model version 2.2 (ED-2.2). In ED-2.2, the biophysical and physiological processes account for the horizontal and vertical heterogeneity of the ecosystem: the energy, water, and carbon cycles are solved separately for a series of vegetation cohorts (groups of individual plants of similar size and plant functional type) distributed across a series of spatially implicit patches (representing collections of micro-environments that have a similar disturbance history). We define the equations that describe the energy, water, and carbon cycles in terms of total energy, water, and carbon, which simplifies the differential equations and guarantees excellent conservation of these quantities in long-term simulation (< 0.1 % error over 50 years). We also show examples of ED-2.2 simulation results at single sites and across tropical South America. These results demonstrate the model's ability to characterize the variability of ecosystem structure, composition, and functioning both at stand and continental scales. A detailed model evaluation was conducted and is presented in a companion paper (Longo et al., 2019a). Finally, we highlight some of the ongoing model developments designed to improve the model's accuracy and performance and to include processes hitherto not represented in the model.

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