Long-term and large-scale storage of natural cold thermal energy in the winter season. (2nd Report, Practical experiment by a scale model).

The long-term settlements in organic clay can create a kind of an engineering challenge that appear in most facilities design and construction in areas with deep deposits of soft clay. Peat ground is widely distributed throughout the southern part of Iraq. Peat contains a large amount of organic matter and has a very high natural water content. Three soil samples were collected from depths of 1.5 m, 2.5 m, and 3.5 m, below the soil surface in Halfaya oilfield, which lies east of Missan governorate southern Iraq. A series of tests were conducted in a large-scale model using a plate footing and considering three different percent of organic content. The percent of secondary settlement found is dependent on the stress level applied. A large fraction of the total settlement may be due to secondary compression. The assumption of a constant coefficient of secondary compression, Cα, may not be valid for a long-term settlement of peats. Laboratory data indicate that Cα generally increases with time. Thus, settlement predictions using constant Cα may underestimate field settlement.

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Comparing lake sediment records of landscape macronutrient loadings with N14CP model simulations: 200 years of change in British lakes

10.5194/egusphere-egu2020-9968 ◽

2020 ◽

Author(s):

John Boyle ◽

Ed Tipping ◽

Jess Davies ◽

Neil Rose ◽

Simon Turner ◽

...

Keyword(s):

Lake Sediment ◽

Large Scale ◽

Process Models ◽

Mountain Lake ◽

Scale Model ◽

Data Sets ◽

Empirical Reality ◽

C Isotopes ◽

Sediment Records

To fully understand coupling between P and other macronutrients it is necessary to have both long-term data sets and process models, combining empirical reality with numerical simulation of coupling processes. Here, lake sediment records of N and P from four UK lakes are compared with model output from N14CP, a long-term, large-scale model of cycling and export of macronutrients from the landscape. The sediment records at the three lakes that have substantial lowland contributions reveal strongly increasing N and P loading through the late 19th century, with steady increases through the twentieth century. Corresponding changes in N and C isotopes are observed. However, the one mountain lake show maximum N and P loadings in the 19th century, with declines through the twentieth, consistent with a wholly different land use history. The N14CP model shows N and P increasing from mid 19th century for average lowland sites, in agreement with the lowland sediment records. The implications of these results for our knowledge about the history of P and N coupling and leaching from UK soils are discussed.

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Dynamic Response of Pile-Board Subgrade Based on Large Scale Model Test

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.383 ◽

2011 ◽

Vol 71-78 ◽

pp. 383-387 ◽

Cited By ~ 1

Author(s):

Qian Su ◽

Xing Li ◽

Hao Bai

Keyword(s):

Dynamic Response ◽

Dynamic Load ◽

Large Scale ◽

Test Group ◽

Structural Type ◽

Scale Model ◽

Load Frequency ◽

Large Scale Model ◽

Supporting Effect

A series of tests based on large scale model are designed to study dynamic response of pile-broad subgrade, aiming at structure’s response towards different load frequency and structure’s performance under long-term dynamic load. The test results indicate that dynamic stress of reinforcement and soil decrease slightly with load frequency, while accelerations trend to increase. Soil under loading plate has certain supporting effect because stress of reinforcement is smaller in test group with soil remains. Performance of pile-board subgrade under long-term dynamic load is steady and reliable since none of stress and displacement varies obviously when loading times increase to 106. Ultimate bearing capacity of pile-board subgrade is much bigger than actual demand, so the structural type of pile-broad plate remains to be optimized.

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Novel Method to Analytically Obtain the Asymptotic Stable Equilibria States of Extended SIR-type Epidemiological Models

10.20944/preprints202105.0644.v1 ◽

2021 ◽

Author(s):

Teddy Lazebnik ◽

Svetlana Bunimovich-Mendrazitsky ◽

Leonid Shaikhet

Keyword(s):

Large Scale ◽

Initial Conditions ◽

Scale Model ◽

Epidemiological Models ◽

Stochastic Representation ◽

Asymptotic Stable ◽

Large Scale Model ◽

Stable Equilibria ◽

Novel Method

We present a new analytical method to find the asymptotic stable equilibria states based on the Markov chain technique. We reveal this method on the SIR-type epidemiological model that we developed for viral diseases with long-term immunity memory pandemic. This is a large-scale model containing 15 nonlinear ODE equations, and classical methods have failed to analytically obtain its equilibria. The proposed method is used to conduct a comprehensive analysis by a stochastic representation of the dynamics of the model, followed by finding all asymptotic stable equilibrium states of the model for any values of parameters and initial conditions.

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Analyzing regimes of mid-latitude atmosphere circulation by novel nonlinear data decomposition method

10.5194/egusphere-egu21-3144 ◽

2021 ◽

Author(s):

Dmitry Mukhin ◽

Abdel Hannachi

Keyword(s):

Large Scale ◽

Winter Season ◽

Principal Component ◽

Empirical Modeling ◽

Kernel Principal Component Analysis ◽

Russian Science ◽

Quasi Biennial Oscillation ◽

Weather Patterns ◽

Dynamical Regimes

We present a new method for identifying dominant dynamical regimes underlying the observed mid-latitude atmospheric circulation. The method combines the partitioning of recurrence networks and kernel principal component analysis. It enables the detection of significant regimes of variability in addition to obtaining dynamical variables which can be used for regimes embedding. The method is applied to the analysis of geopotential height anomalies of the mid-latitude atmosphere in the Northern hemisphere for the 1981-present winter season. The identified regimes as well as the set of dynamical variables explain large-scale weather patterns, which are associated, e.g., with severe winters over Eurasia and North America. Pronounced inter-annual signatures are also found in the long-term dynamics of the regimes&#8217; frequencies, which are shown to be closely related to the quasi-biennial oscillation of the tropical stratosphere. The method is presented, and prospects for empirical modeling of the atmosphere circulation regimes, and long-term climate predictability are discussed. The work is supported by the Russian Science Foundation (grant 19-42-04121).

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Novel Method to Analytically Obtain the Asymptotic Stable Equilibria States of Extended SIR-Type Epidemiological Models

Symmetry ◽

10.3390/sym13071120 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1120

Author(s):

Teddy Lazebnik ◽

Svetlana Bunimovich-Mendrazitsky ◽

Leonid Shaikhet

Keyword(s):

Large Scale ◽

Initial Conditions ◽

Scale Model ◽

Epidemiological Models ◽

Stochastic Representation ◽

Asymptotic Stable ◽

Large Scale Model ◽

Stable Equilibria ◽

Novel Method

We present a new analytical method to find the asymptotic stable equilibria states based on the Markov chain technique. We reveal this method on the Susceptible-Infectious-Recovered (SIR)-type epidemiological model that we developed for viral diseases with long-term immunity memory. This is a large-scale model containing 15 nonlinear ordinary differential equations (ODEs), and classical methods have failed to analytically obtain its equilibria. The proposed method is used to conduct a comprehensive analysis by a stochastic representation of the dynamics of the model, followed by finding all asymptotic stable equilibrium states of the model for any values of parameters and initial conditions thanks to the symmetry of the population size over time.

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A 100-m-Scale Modeling Study of a Gale Event on the Lee Side of a Long Narrow Mountain

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-19-0066.1 ◽

2020 ◽

Vol 59 (1) ◽

pp. 23-45 ◽

Cited By ~ 2

Author(s):

Haile Xue ◽

Jian Li ◽

Tingting Qian ◽

Hongping Gu

Keyword(s):

Large Scale ◽

Winter Season ◽

Wave Theory ◽

Early Morning ◽

Horizontal Resolution ◽

Scale Model ◽

Wind Fields ◽

Eddy Simulation ◽

Downslope Wind ◽

Lee Waves

AbstractIn this study, a gale event that occurred on the lee side of a long narrow mountain was investigated, together with the associated mountain flows, using a realistic-case large-eddy simulation (LES) that is based on the Weather Research and Forecasting Model. The mountain is located on the southeastern Tibetan Plateau, where approximately 58 gales occur annually, mostly in the afternoons during the winter season. Benefitting from realistic topography and high horizontal resolution as fine as 111 m, the LES can replicate features similar to the wind fields observed during the gale period. Investigation of the early morning wind structure over the mountain revealed that weak inflows were blocked, reversed, and divided in the upstream area and that some weak lee waves, rotors, and two clear lee vortices were evident downstream. As the upstream wind accelerated and the boundary layer developed during the daytime, the lee waves became amplified with severe downslope wind and rotors. The interaction and coherent structure of the downslope wind, rotor, and vortices were investigated to show the severe wind distribution. The mountain drags associated with blocking and amplified lee waves are displayed to show the potential impact on the large-scale model. The linear lee-wave theory was adopted to explain the wave evolution during this event together with a discussion of the uncertainty around low-level nonlinear processes.

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Regional simulation of long-term organic carbon stock changes in cropland soils using the DNDC model: 1. Large-scale model validation against a spatially explicit data set

Soil Use and Management ◽

10.1111/j.1475-2743.2006.00045.x ◽

2006 ◽

Vol 22 (4) ◽

pp. 342-351 ◽

Cited By ~ 17

Author(s):

S. Sleutel ◽

S. De Neve ◽

D. Beheydt ◽

C. Li ◽

G. Hofman

Keyword(s):

Large Scale ◽

Scale Model ◽

Spatially Explicit ◽

Dndc Model ◽

Data Set ◽

Large Scale Model ◽

Regional Simulation ◽

Spatially Explicit Data ◽

Organic Carbon Stock

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Sequestration of CO2 in Geological Media: A Case Study of the Saline Reservoir Using Parallel Computing for Multi-Well Injection

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.1468 ◽

2013 ◽

Vol 284-287 ◽

pp. 1468-1472 ◽

Cited By ~ 1

Author(s):

Chien Hao Tseng ◽

Chia Chen Kuo ◽

Wei Chih Su ◽

Chuan Lin Lai

Keyword(s):

Carbon Dioxide ◽

Parallel Computing ◽

Large Scale ◽

Scale Model ◽

Heterogeneous Model ◽

Injection Model ◽

And Storage ◽

Saline Reservoir

Carbon-Dioxide Capture and Storage (CCS) in deep saline aquifers is one of the most feasible techniques for reducing anthropogenic emission of carbon dioxide (CO2). In this paper, a high-performance parallel computing is used to simulate the large-scale and long-term CO2 geologic storage in the saline aquifer (Sleipner Vest field in the Norwegian) based on the ECO2N module of the flow/transport simulator TOUGH2-MP, which is the parallel version of TOUGH2 implemented by the MPI. We have developed a complex three-dimensional heterogeneous model to study the spatial and temporal distribution and storage of CO2 injection into the sands of the Utsira formation, at the Sleipner Vest field in the Norway. Simulation results demonstrate that the high-speed parallel computing enhanced the capability on handling the large-scale model and the long-term studies. Furthermore, in order to avoid the problems of overpressure in the saline reservoir, the case study employs multi-well (ten-well) injection model, which has been proven to be able to reduce the reservoir pressure effectively when compared to the single-well injection model.

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