Search results for "uncertainty"
showing 10 items of 1010 documents
A hybrid statistical decision-making optimization approach for groundwater vulnerability considering uncertainty.
2021
Recognizing the vulnerable areas for contamination is a feasible way to protect groundwater resources. The main contribution of the paper is developing a hybrid statistical decision-making model for evaluating the vulnerability of Shiraz aquifer, southern Iran, with modified DRASTIC (depth to the water table, net recharge, aquifer media, soil media, topography, impact of the vadose zone, and hydraulic conductivity) by using the genetic algorithm (GA), the analytical hierarchy process (AHP) method, and factorial analysis (FA). First, considering the variation of the uncertain parameters, 32 scenarios were defined to perform factorial analysis. Then using the AHP method and GA, DRASTIC parame…
Statistical upscaling of ecosystem CO2 fluxes across the terrestrial tundra and boreal domain: Regional patterns and uncertainties
2021
The regional variability in tundra and boreal carbon dioxide (CO2) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990–2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to a…
Applicability and consequences of the integration of alternative models for CO2 transfer velocity into a process-based lake model
2019
Freshwater lakes are important in carbon cycling, especially in the boreal zone where many lakes are supersaturated with the greenhouse gas carbon dioxide (CO2) and emit it to the atmosphere, thus ventilating carbon originally fixed by the terrestrial system. The exchange of CO2 between water and the atmosphere is commonly estimated using simple wind-based parameterizations or models of gas transfer velocity (k). More complex surface renewal models, however, have been shown to yield more correct estimates of k in comparison with direct CO2 flux measurements. We incorporated four gas exchange models with different complexity into a vertical process-based physico-biochemical lake model, MyLak…
Solidarity in games with a coalition structure
2010
Abstract A new axiomatic characterization of the two-step Shapley value Kamijo (2009) is presented based on a solidarity principle of the members of any union: when the game changes due to the addition or deletion of players outside the union, all members of the union will share the same gains/losses.
Perception du risque dépendance et demande d'assurance : une analyse à partir de l'enquête PATER
2013
Dans la littérature économique, de nombreux travaux tentent d'expliquer pourquoi les individus s’assurent aussi peu contre la dépendance. Du côté de l’offre, différents freins possibles au développement du marché de l’assurance dépendance ont d’ores et déjà été pointés du doigt par la littérature. Les estimations récentes montrent néanmoins que les limites imputables à l’offre ne suffisent pas à expliquer le faible développement du marché : même si les assurances étaient moins coûteuses et les couvertures proposées plus larges, la majorité des individus ne souscrirait toujours pas d’assurance. Il est donc nécessaire d’aller trouver des explications du côté de la demande d’assurance dépendan…
Accounting for soil parameter uncertainty in a physically based and distributed approach for rainfall-triggered landslides
2016
In this study we propose a probabilistic approach for coupled distributed hydrological-hillslope stability models that accounts for soil parameters uncertainty at basin scale. The geotechnical and soil retention curve parameters are treated as random variables across the basin and theoretical probability distributions of the Factor of Safety (FS) are estimated. The derived distributions are used to obtain the spatio-temporal dynamics of probability of failure, in terms of parameters uncertainty, conditioned to soil moisture dynamics. The framework has been implemented in the tRIBS-VEGGIE (Triangulated Irregular Network (TIN)-based Real-time Integrated Basin Simulator-VEGetation Generator fo…
Incertezza, precarietà, capacità di immaginazione del futuro e modernità: un confronto tra Appadurai e De Martino
2017
Though apparently distanced for their temporal and historical moment, their conceptual terminology, their interlocutors and the fields of their empirical research, it is possible to get some notable parallelisms of theoretical vision between the anthropological work of De Martino and that of Appadurai. In both cases, their starting point is in fact the uncertainty of human condition and social orders, and at the heart of their theory, there stands the issue of identifying the different kinds of ethos and cultural activity which permit people to historically and existentially confront this uncertainty through establishing their belonging to a “cultural homeland” (De Martino) or forms of soci…
Economics of Esports
2019
In this paper, esports market development is exhibited and analyzed through various data sources and literature review. Additionally, economic concepts are applied to the esports environment. Demand characteristics of this emerging market are analyzed by applying the concept of competitive balance as commonly used in economics of sport scrutiny. The elite esports demand is proxied by gathering data on total prize money in the elite esports tournaments and explaining the esports demand by testing various factors measuring the competitive market properties. The most commonly used measurement in economics of sport for measuring withinseason competitive balance is calculated as the actual stand…
The Truth is Out There : Focusing on Smaller to Guess Bigger in Image Classification
2023
In Artificial Intelligence (AI) in general and in Machine Learning (ML) in particular, which are important and integral components of modern Industry 4.0, we often deal with uncertainty, e.g., lack of complete information about the objects we are classifying, recognizing, diagnosing, etc. Traditionally, uncertainty is considered to be a problem especially in the responsible use of AI and ML tools in the smart manufacturing domain. However, in this study, we aim not to fight with but rather to benefit from the uncertainty to improve the classification performance in supervised ML. Our objective is a kind of uncertainty-driven technique to improve the performance of Convolutional Neural Netwo…
Uncertainty management in the measurements of low frequency magnetic fields
2014
The paper deals with low-frequency magnetic field measurements carried out by using a broadband and isotropic instrument. These measurements are characterized by very high uncertainty values, which imply a high risk of wrong decisions when there is the need to establish if a site complies or does not comply with specified emission limits. To reduce this risk, we decided to perform the so called “uncertainty management” that is the discipline of optimizing the cost of a measurement versus the uncertainty target. The task is achieved by using the PUMA method that is an iterative technique originally conceived for geometrical and mechanical measurements. The approach is completely based on the…