scholarly journals Probabilistic Method to Assess Model Uncertainty of Rigid Inclusion on a Granular Fill Supporting a Slab Foundation

2020 ◽  
Vol 10 (21) ◽  
pp. 7885 ◽  
Author(s):  
Félix Escolano Sánchez ◽  
Manuel Bueno Aguado ◽  
Eugenio Sanz Pérez

Probabilistic approaches to deal with uncertainty on soil mechanic predictions are on the rise. We developed a procedure to deal with uncertainty coming from soil conditions. It was applied to an analytical model to simulate the behavior of a soil improvement work based on rigid inclusion below a slab foundation. The model can predict the settlements of the slab. Even more, it was also able to provide a confidence level based on a probabilistic approach to the input’s variables. Outputs were compared to large-scale tests. The agreement is outstanding. We try to encourage the use of probabilistic models to solve complex geotechnical problems.

2014 ◽  
Vol 53 (3) ◽  
pp. 660-675 ◽  
Author(s):  
Megan C. Kirchmeier ◽  
David J. Lorenz ◽  
Daniel J. Vimont

AbstractThis study presents the development of a method to statistically downscale daily wind speed variations in an extended Great Lakes region. A probabilistic approach is used, predicting a daily-varying probability density function (PDF) of local-scale daily wind speed conditioned on large-scale daily wind speed predictors. Advantages of a probabilistic method are that it provides realistic information on the variance and extremes in addition to information on the mean, it allows the autocorrelation of downscaled realizations to be tuned to match the autocorrelation of local-scale observations, and it allows flexibility in the use of the final downscaled product. Much attention is given to fitting the proper functional form of the PDF by investigating the observed local-scale wind speed distribution (predictand) as a function of the decile of the large-scale wind (predictor). It is found that the local-scale standard deviation and the local-scale shape parameter (from a gamma distribution) are nonconstant functions of the large-scale predictor. As such, a vector generalized linear model is developed to relate the large-scale and local-scale wind speeds. Maximum likelihood and cross validation are used to fit local-scale gamma distribution shape and scale parameters to the large-scale wind speed. The result is a daily-varying probability distribution of local-scale wind speed, conditioned on the large-scale wind speed.


2014 ◽  
Vol 30 (1) ◽  
pp. 111-129 ◽  
Author(s):  
Liam M. Wotherspoon ◽  
Rolando P. Orense ◽  
Mike Jacka ◽  
Russell A. Green ◽  
Brady R. Cox ◽  
...  

The city of Christchurch and the surrounding region on the South Island of New Zealand are underlain by large areas of recent alluvial sediments and fills that are highly susceptible to liquefaction and seismic ground failure. Thus, the widespread liquefaction that occurred following the successive large-scale earth-quakes, with moment magnitudes (MW) ranging from 6.0 to 7.1 that struck the Canterbury region in 2010–2011 was expected. Prior to the series of earthquakes, soil improvement had been used at several sites to mitigate the anticipated damage. This paper reviews the performance of improved sites during the Canterbury earthquake sequence. The existing soil conditions at each site and the design of the ground improvement are discussed, together with descriptions of the post-earthquake damage observed. Moreover, liquefaction assessment within and surrounding a selection of the ground improvement zones is presented.


2002 ◽  
Vol 24 (2) ◽  
pp. 189-208 ◽  
Author(s):  
Akihito Kamata ◽  
Gershon Tenenbaum ◽  
Yuri L. Hanin

The Individual Zone of Optimal Functioning (IZOF) model postulates the functional relationship between emotions and optimal performance, and aims to predict the quality of upcoming performance with respect to the pre-performance emotional state of the performer. Several limitations associated with the traditional method of determining the IZOF are outlined and a new probabilistic approach is introduced instead. To reliably determine the boundaries of the IZOF and their associated probabilistic curve thresholds, performance outcomes that vary in quality, as well as the emotional intensity associated with them, are taken into account. Several probabilistic models of varying complexity are presented, along with hypothetical and real data to illustrate the concept. The traditional and the new methods are contrasted in one actual set and two hypothetical sets of data. In all cases the proposed probabilistic method was found to show greater sensitivity and to more accurately represent the data than the traditional method. The development of the method is a first stage toward developing models that take into account the interactive nature and multidimensionality of the emotional construct, as well as the fluctuations in emotional intensity and performance throughout the competition phases (i.e., momentum).


Computers ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 82
Author(s):  
Ahmad O. Aseeri

Deep Learning-based methods have emerged to be one of the most effective and practical solutions in a wide range of medical problems, including the diagnosis of cardiac arrhythmias. A critical step to a precocious diagnosis in many heart dysfunctions diseases starts with the accurate detection and classification of cardiac arrhythmias, which can be achieved via electrocardiograms (ECGs). Motivated by the desire to enhance conventional clinical methods in diagnosing cardiac arrhythmias, we introduce an uncertainty-aware deep learning-based predictive model design for accurate large-scale classification of cardiac arrhythmias successfully trained and evaluated using three benchmark medical datasets. In addition, considering that the quantification of uncertainty estimates is vital for clinical decision-making, our method incorporates a probabilistic approach to capture the model’s uncertainty using a Bayesian-based approximation method without introducing additional parameters or significant changes to the network’s architecture. Although many arrhythmias classification solutions with various ECG feature engineering techniques have been reported in the literature, the introduced AI-based probabilistic-enabled method in this paper outperforms the results of existing methods in outstanding multiclass classification results that manifest F1 scores of 98.62% and 96.73% with (MIT-BIH) dataset of 20 annotations, and 99.23% and 96.94% with (INCART) dataset of eight annotations, and 97.25% and 96.73% with (BIDMC) dataset of six annotations, for the deep ensemble and probabilistic mode, respectively. We demonstrate our method’s high-performing and statistical reliability results in numerical experiments on the language modeling using the gating mechanism of Recurrent Neural Networks.


2013 ◽  
Vol 38 ◽  
pp. 1-15 ◽  
Author(s):  
Ahmet Demir ◽  
Mustafa Laman ◽  
Abdulazim Yildiz ◽  
Murat Ornek

1951 ◽  
Vol 41 (1-2) ◽  
pp. 149-162 ◽  
Author(s):  
H. H. Nicholson ◽  
G. Alderman ◽  
D. H. Firth

1. The methods of investigation of the effect of ground water-level on crop growth, together with tho field installations in use, are discussed.2. Direct field experiments are handicapped by the difficulties of achieving close control on a sufficiently large scale, due to considerable variations of surface level and depth of peat within individual fields and to rapid fluctuations in rainfall and evaporation. Many recorded experiments are associated with climatic conditions of substantial precipitation during the growing season.3. Seasonal fluctuations of ground water-level in Fen peat soils in England, in natural and agricultural conditions, are described.4. The local soil conditions are outlined and the implications of profile variations are discussed.5. The effective control of ground water-level on a field scale requires deep and commodious ditches and frequent large underdrains to ensure the movement of water underground with sufficient freedom to give rapid compensatory adjustment for marked disturbances of ground water-level following the incidence of heavy rain or excessive evaporation.6. A working installation for a field experiment in ordinary farming conditions is described and the measure of control attained is indicated.


Author(s):  
Christopher Cammies ◽  
David Mytton ◽  
Rosemary Crichton

AbstractAquaponics is a food production system which connects recirculating aquaculture (fish) to hydroponics (plants) systems. Although aquaponics has the potential to improve soil conditions by reducing erosion and nutrient loss and has been shown to reduce food production related carbon emissions by up to 73%, few commercial aquaponics projects in the EU and UK have been successful. Key barriers to commercial success are insufficient initial investment, an uncertain and complex regulatory environment, and the lack of projects operating on a large scale able to demonstrate profitability. In this paper, we use the UK as a case study to discuss the legal and economic barriers to the success of commercial aquaponics in the EU. We also propose three policies: (1) making aquaponics eligible for the new system of Environmental Land Management grants; (2) making aquaponics eligible for organic certification; and (3) clarifying and streamlining the aquaponics licence application process. The UK’s departure from the EU presents a unique opportunity to review agricultural regulations and subsidies, which in turn could provide evidence that similar reforms are needed in the EU.


1969 ◽  
Vol 41 (3) ◽  
pp. 179-188
Author(s):  
M. A. Lugo-López ◽  
J. A. Bonnet ◽  
R. Pérez-Escolar

Data are presented here on the effect of synthetic soil conditioners on aggregation and aggregate stability of acid Lares clay and on their effect, with or without lime, on the yields of sweetpotatoes, cotton, and corn. Three conditioners were used: Formulations 6 and 9 of Krilium, and Aerotil, dry form, each at the rates of 900, 1,800, and 3,600 pounds to the acre. There were 20 treatments: Check, lime, conditioners at three levels, and conditioners at the same three levels plus lime. The data presented indicate that these conditioners will stabilize soil structural units, but will not form them. Five crops were grown as a sequence: Sweetpotatoes, cotton, cotton (a ratoon crop), sweetpotatoes, and corn. All crops, except the cotton ratoon, showed some response to the application of soil conditioners. Sweetpotato, a root crop, was more responsive; but the cotton plant crop responded also to stabilized good structural soil conditions. The largest crop responses measured were in the limed treatments. Increases attributable to lime were obtained either in the presence or absence of synthetic soil conditioners. Liming and rational fertilization seems to be the key to increased productivity in some acid soils of Puerto Rico. The synthetic materials do not have practical possibilities in large-scale farming.


2021 ◽  
Author(s):  
Carl-Fredrik Johannesson ◽  
Klaus Steenberg Larsen ◽  
Brunon Malicki ◽  
Jenni Nordén

<p>Boreal forests are among the most carbon (C) rich forest types in the world and store up to 80% of its total C in the soil. Forest soil C development under climate change has received increased scientific attention yet large uncertainties remain, not least in terms of magnitude and direction of soil C responses. As with climate change, large uncertainties remain in terms of the effects of forest management on soil C sequestration and storage. Nonetheless, it is clear that forest management measures can have far reaching effects on ecosystem functioning and soil conditions. For example, clear cutting is a widely undertaken felling method in Scandinavia which profoundly affects the forest ecosystem and its functioning, including the soil. Nitrogen (N) fertilization is another common practice in Scandinavia which, despite uncertainties regarding effects on soil C dynamics, is being promoted as a climate change mitigation tool. A more novel practice of biochar addition to soils has been shown to have positive effects on soil conditions, including soil C storage, but studies on biochar in the context of forests are few.</p><p>In the face of climate change, the ForBioFunCtioN project is dedicated to investigating the response of boreal forest soil CO<sub>2</sub> and CH<sub>4</sub> fluxes to experimentally increased temperatures and increased precipitation – climatic changes in line with projections over Norway – within a forest management context. The experiment is set in a Norwegian spruce-dominated bilberry chronosequence, including a clear-cut site, a middle-aged thinned stand, a mature stand and an old unmanaged stand. Warming, simulated increased precipitation, N fertilizer and biochar additions will be applied on experimental plots in an additive manner that allows for disentangling the effects of individual parameters from interaction effects. Flux measurements will be undertaken at high temporal resolution using the state-of-the-art LI-7810 Trace Gas Analyzer (©LI-COR Biosciences). The presentation will show the experimental setup and first measurements from the large-scale experiment.</p>


Author(s):  
Jerzy Antoni Żurański ◽  
Andrzej Sobolewski

The paper deals with the probabilistic method of the assessment of the depth of soil freezing. Annual (winter) maxima of the position of the zero centigrade temperature measured in the soil were approximated by Gumbel probability distribution. Its parameters were estimated using maximum likelihood method. Results received on the base of data from 2 meteorological stations and 30 years of observations, called as characteristic values of 50-year return period, refelect the influence of the climatic conditions on the freezing depth. On the other hand the soil structure and its conditions also play an important role in freezing. Nowadays they may be taken into account using correction coefficients. It is concluded that this methods is more precise than a method using so called air freezing index. Received results are not the same as given in the old Polish Standard. New analysis is currently being done.


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