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Littérature scientifique sur le sujet « Sensitivity indices »

Auteur : Grafiati
Publié le 9 mars 2023
Mis à jour le 11 mars 2023

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Articles de revues sur le sujet "Sensitivity indices"

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Lamboni, Matieyendou. « Derivative-based generalized sensitivity indices and Sobol’ indices ». Mathematics and Computers in Simulation 170 (avril 2020) : 236–56. http://dx.doi.org/10.1016/j.matcom.2019.10.017.

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Xu, Chonggang, et George Zdzislaw Gertner. « Reliability of global sensitivity indices ». Journal of Statistical Computation and Simulation 81, no 12 (décembre 2011) : 1939–69. http://dx.doi.org/10.1080/00949655.2010.509317.

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Da Veiga, Sébastien, et Fabrice Gamboa. « Efficient estimation of sensitivity indices ». Journal of Nonparametric Statistics 25, no 3 (septembre 2013) : 573–95. http://dx.doi.org/10.1080/10485252.2013.784762.

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Gamboa, Fabrice, Alexandre Janon, Thierry Klein et Agnès Lagnoux. « Sensitivity indices for multivariate outputs ». Comptes Rendus Mathematique 351, no 7-8 (avril 2013) : 307–10. http://dx.doi.org/10.1016/j.crma.2013.04.016.

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Izsák, János. « Sensitivity Profiles of Diversity Indices ». Biometrical Journal 38, no 8 (1996) : 921–30. http://dx.doi.org/10.1002/bimj.4710380804.

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MacArthur, Lauren A. « Dust Sensitivity of Absorption‐Line Indices ». Astrophysical Journal 623, no 2 (20 avril 2005) : 795–814. http://dx.doi.org/10.1086/428827.

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Janon, Alexandre, Maëlle Nodet et Clémentine Prieur. « Certified metamodels for sensitivity indices estimation ». ESAIM : Proceedings 35 (mars 2012) : 234–38. http://dx.doi.org/10.1051/proc/201235020.

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Salome, C. M., N. J. Brown, H. K. Reddel, W. Xuan et G. B. Marks. « Indices of bronchial reactivity and sensitivity ». Thorax 66, no 3 (27 octobre 2010) : 265–66. http://dx.doi.org/10.1136/thx.2010.151639.

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Chung, C. Y., C. T. Tse, R. Niu et K. W. Wang. « PSS Design by Probabilistic Sensitivity Indices ». IEEE Power Engineering Review 22, no 7 (juillet 2002) : 56. http://dx.doi.org/10.1109/mper.2002.4312394.

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Lasersohn, Peter. « Non-World Indices and Assessment-Sensitivity ». Inquiry 56, no 2-3 (avril 2013) : 122–48. http://dx.doi.org/10.1080/0020174x.2013.784463.

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Thèses sur le sujet "Sensitivity indices"

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GIOIA, PAOLA. « Towards more accurate measures of global sensitivity analysis. Investigation of first and total order indices ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/45695.

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A new technique for estimating variance–based total sensitivity indices from given data is developed. It is also develped a new approach for the estimation of the first order effects given a specific sample design. This method adopts the RBD approach published by Tarantola et al., (2007) for the computation of first order sensitivity indices in association to Quasi–Random numbers.
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Fernandez, Chas Margarita. « Insulin sensitivity estimates from a linear model of glucose disappearance ». Thesis, University of Sussex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341544.

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Moore, Alan D. « Reproducibility and sensitivity of Doppler echocardiographic indices of left ventricular function during exercise ». Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/53648.

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The two most common methods used for the assessment of left ventricular function (LVF) are two-dimensional echocardiography and nuclear ventriculography. Recent technological advances have led to the development of an inexpensive, noninvasive alternative: the stand-alone continuous wave Doppler echocardiograph. The purposes cf this study were twofold: 1) to examine the repeatability of three Doppler measured indices of LVF during repeated exercise trials, and 2) to determine if induced changes in myocardial contractility would be reflected by changes in the Doppler indices. The Doppler indices of LVF were the peak acceleration of ascending aortic blood (pkA), peak Velocity of ascending aortic blood (pkV), and the integral of the Velocity-time waveform (SVI). The study was conducted in two phases. In the first phase, 44 young, healthy males performed similar graded cycle exercise tasks on two separate days. Exercise levels were increased by 50 W every three minutes. PkA, pkV, SVI, blood pressure, heart rate and oxygen consumption were recorded every stage. The test was continued until the subject reached symptom-limited maximum. Pearson product-moment correlation coefficients were used to determine the reproducibility of the dependent measures between the two tests. The second phase involved the testing of a subset of the original 44 subjects (N=18) under a placebo (control) condition, acute beta-blockade, and oral hyperhydration states. Hematocrit was measured as a means to assess blood volume changes. The subjects exercised at levels requiring 20, 40 and 60% of their maximum oxygen consumption. Each stage lasted six minutes. PkA, pkV, SVI, heart rate, blood pressure, cardiac output, and stroke volume were measured. The latter two were determined by a carbon dioxide rebreathing technique. This was a split-plot design with multiple dependent measures. The statistical analysis was a multivariate analysis of variance (MANOVA) with repeated measures. Appropriate univariate tests were utilized as post-hoc procedures. With respect to the first phase, the correlation coefficients for pkA ranged from 0.54-0.81, for pkV, 0.65-0.77, and for SVI, 0.40-0.71. The results of the second phase indicated that alterations in contractile status by beta-blockade was reflected by changes in the Doppler measures, but the hyperhydration state did not produce a change in cardiac contractile response that was detectable. There were no documented changes in plasma volume as measured by change in hematocrit, therefore, the effectiveness of the hyperhydration procedure was judged ineffective. PkA and pkV were significantly reduced (p<.01) at all stages of exercise in the beta-blocked state as compared to the placebo values. Cardiac output and heart rate were significantly lower in the beta-blocked state, and stroke volume was significantly higher. The results of this experiment indicates that continuous wave Doppler echocardiographic estimates of LVF are reproducible (r=0.40-0.81) and reflect changes in myocardial contractility induced by acute beta-blockade.
Ph. D.
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Wajahat, Qazi Hassan. « Development of Sensitivity Based Indices for Optimal Placement of UPFC to Minimize Load Curtailment Requirements ». Thesis, KTH, Elektriska energisystem, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119252.

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Chastaing, Gaëlle. « Indices de Sobol généralisés par variables dépendantes ». Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENM046.

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Dans un modèle qui peut s'avérer complexe et fortement non linéaire, les paramètres d'entrée, parfois en très grand nombre, peuvent être à l'origine d'une importante variabilité de la sortie. L'analyse de sensibilité globale est une approche stochastique permettant de repérer les principales sources d'incertitude du modèle, c'est-à-dire d'identifier et de hiérarchiser les variables d'entrée les plus influentes. De cette manière, il est possible de réduire la dimension d'un problème, et de diminuer l'incertitude des entrées. Les indices de Sobol, dont la construction repose sur une décomposition de la variance globale du modèle, sont des mesures très fréquemment utilisées pour atteindre de tels objectifs. Néanmoins, ces indices se basent sur la décomposition fonctionnelle de la sortie, aussi connue soue le nom de décomposition de Hoeffding. Mais cette décomposition n'est unique que si les variables d'entrée sont supposées indépendantes. Dans cette thèse, nous nous intéressons à l'extension des indices de Sobol pour des modèles à variables d'entrée dépendantes. Dans un premier temps, nous proposons une généralisation de la décomposition de Hoeffding au cas où la forme de la distribution des entrées est plus générale qu'une distribution produit. De cette décomposition généralisée aux contraintes d'orthogonalité spécifiques, il en découle la construction d'indices de sensibilité généralisés capable de mesurer la variabilité d'un ou plusieurs facteurs corrélés dans le modèle. Dans un second temps, nous proposons deux méthodes d'estimation de ces indices. La première est adaptée à des modèles à entrées dépendantes par paires. Elle repose sur la résolution numérique d'un système linéaire fonctionnel qui met en jeu des opérateurs de projection. La seconde méthode, qui peut s'appliquer à des modèles beaucoup plus généraux, repose sur la construction récursive d'un système de fonctions qui satisfont les contraintes d'orthogonalité liées à la décomposition généralisée. En parallèle, nous mettons en pratique ces différentes méthodes sur différents cas tests
A mathematical model aims at characterizing a complex system or process that is too expensive to experiment. However, in this model, often strongly non linear, input parameters can be affected by a large uncertainty including errors of measurement of lack of information. Global sensitivity analysis is a stochastic approach whose objective is to identify and to rank the input variables that drive the uncertainty of the model output. Through this analysis, it is then possible to reduce the model dimension and the variation in the output of the model. To reach this objective, the Sobol indices are commonly used. Based on the functional ANOVA decomposition of the output, also called Hoeffding decomposition, they stand on the assumption that the incomes are independent. Our contribution is on the extension of Sobol indices for models with non independent inputs. In one hand, we propose a generalized functional decomposition, where its components is subject to specific orthogonal constraints. This decomposition leads to the definition of generalized sensitivity indices able to quantify the dependent inputs' contribution to the model variability. On the other hand, we propose two numerical methods to estimate these constructed indices. The first one is well-fitted to models with independent pairs of dependent input variables. The method is performed by solving linear system involving suitable projection operators. The second method can be applied to more general models. It relies on the recursive construction of functional systems satisfying the orthogonality properties of summands of the generalized decomposition. In parallel, we illustrate the two methods on numerical examples to test the efficiency of the techniques
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Horiguchi, Akira. « Bayesian Additive Regression Trees : Sensitivity Analysis and Multiobjective Optimization ». The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1606841319315633.

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Masinde, Brian. « Birds' Flight Range. : Sensitivity Analysis ». Thesis, Linköpings universitet, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166248.

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’Flight’ is a program that uses flight mechanics to estimate the flight range of birds. This program, used by ornithologists, is only available for Windows OS. It requires manual imputation of body measurements and constants (one observation at a time) and this is time-consuming. Therefore, the first task is to implement the methods in R, a programming language that runs on various platforms. The resulting package named flying, has three advantages; first, it can estimate flight range of multiple bird observations, second, it makes it easier to experiment with different settings (e.g. constants) in comparison to Flight and third, it is open-source making contribution relatively easy. Uncertainty and global sen- sitivity analyses are carried out on body measurements separately and with various con- stants. In doing so, the most influential body variables and constants are discovered. This task would have been near impossible to undertake using ’Flight’. A comparison is made amongst the results from a crude partitioning method, generalized additive model, gradi- ent boosting machines and quasi-Monte Carlo method. All of these are based on Sobol’s method for variance decomposition. The results show that fat mass drives the simulations with other inputs playing a secondary role (for example mechanical conversion efficiency and body drag coefficient).
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Seol, Huynsoo. « Sensitivity of five Rasch-model-based fit indices to selected person and item aberrances : a simulation study / ». The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487949508369046.

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Heredia, Guzman Maria Belen. « Contributions to the calibration and global sensitivity analysis of snow avalanche numerical models ». Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALU028.

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Une avalanche de neige est un danger naturel défini comme une masse de neige en mouvement rapide. Depuis les années 30, scientifiques conçoivent des modèles d'avalanche de neige pour décrire ce phénomène. Cependant, ces modèles dépendent de certains paramètres d'entrée mal connus qui ne peuvent pas être mesurés. Pour mieux comprendre les paramètres d'entrée du modèle et les sorties du modèle, les objectifs de cette thèse sont (i) de proposer un cadre pour calibrer les paramètres d'entrée et (ii) de développer des méthodes pour classer les paramètres d'entrée en fonction de leur importance dans le modèle en tenant compte la nature fonctionnelle des sorties. Dans ce cadre, nous développons des méthodes statistiques basées sur l'inférence bayésienne et les analyses de sensibilité globale. Nos développements sont illustrés sur des cas de test et des données réelles des avalanches de neige.D'abord, nous proposons une méthode d'inférence bayésienne pour récupérer la distribution des paramètres d'entrée à partir de séries chronologiques de vitesse d'avalanche ayant été collectées sur des sites de test expérimentaux. Nos résultats montrent qu'il est important d'inclure la structure d'erreur (dans notre cas l'autocorrélation) dans la modélisation statistique afin d'éviter les biais dans l'estimation des paramètres de frottement.Deuxièmement, pour identifier les paramètres d'entrée importants, nous développons deux méthodes basées sur des mesures de sensibilité basées sur la variance. Pour la première méthode, nous supposons que nous avons un échantillon de données et nous voulons estimer les mesures de sensibilité avec cet échantillon. Dans ce but, nous développons une procédure d'estimation non paramétrique basée sur l'estimateur de Nadaraya-Watson pour estimer les indices agrégés de Sobol. Pour la deuxième méthode, nous considérons le cadre où l'échantillon est obtenu à partir de règles d'acceptation/rejet correspondant à des contraintes physiques. L'ensemble des paramètres d'entrée devient dépendant du fait de l'échantillonnage d'acceptation-rejet, nous proposons donc d'estimer les effets de Shapley agrégés (extension des effets de Shapley à des sorties multivariées ou fonctionnelles). Nous proposons également un algorithme pour construire des intervalles de confiance bootstrap. Pour l'application du modèle d'avalanche de neige, nous considérons différents scénarios d'incertitude pour modéliser les paramètres d'entrée. Dans nos scénarios, la position et le volume de départ de l'avalanche sont les entrées les plus importantes.Nos contributions peuvent aider les spécialistes des avalanches à (i) prendre en compte la structure d'erreur dans la calibration du modèle et (ii) proposer un classementdes paramètres d'entrée en fonction de leur importance dans les modèles en utilisant des approches statistiques
Snow avalanche is a natural hazard defined as a snow mass in fast motion. Since the thirties, scientists have been designing snow avalanche models to describe snow avalanches. However, these models depend on some poorly known input parameters that cannot be measured. To understand better model input parameters and model outputs, the aims of this thesis are (i) to propose a framework to calibrate input parameters and (ii) to develop methods to rank input parameters according to their importance in the model taking into account the functional nature of outputs. Within these two purposes, we develop statistical methods based on Bayesian inference and global sensitivity analyses. All the developments are illustrated on test cases and real snow avalanche data.First, we propose a Bayesian inference method to retrieve input parameter distribution from avalanche velocity time series having been collected on experimental test sites. Our results show that it is important to include the error structure (in our case the autocorrelation) in the statistical modeling in order to avoid bias for the estimation of friction parameters.Second, to identify important input parameters, we develop two methods based on variance based measures. For the first method, we suppose that we have a given data sample and we want to estimate sensitivity measures with this sample. Within this purpose, we develop a nonparametric estimation procedure based on the Nadaraya-Watson kernel smoother to estimate aggregated Sobol' indices. For the second method, we consider the setting where the sample is obtained from acceptance/rejection rules corresponding to physical constraints. The set of input parameters become dependent due to the acceptance-rejection sampling, thus we propose to estimate aggregated Shapley effects (extension of Shapley effects to multivariate or functional outputs). We also propose an algorithm to construct bootstrap confidence intervals. For the snow avalanche model application, we consider different uncertainty scenarios to model the input parameters. Under our scenarios, the release avalanche position and volume are the most crucial inputs.Our contributions should help avalanche scientists to (i) account for the error structure in model calibration and (ii) rankinput parameters according to their importance in the models using statistical methods
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Tissot, Jean-yves. « Sur la décomposition ANOVA et l'estimation des indices de Sobol'. Application à un modèle d'écosystème marin ». Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENM064/document.

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Dans les domaines de la modélisation et de la simulation numérique, les simulateurs développés prennent parfois en compte de nombreux paramètres dont l'impact sur les sorties n'est pas toujours bien connu. L'objectif principal de l'analyse de sensibilité est d'aider à mieux comprendre comment les sorties d'un modèle sont sensibles aux variations de ces paramètres. L'approche la mieux adaptée pour appréhender ce problème dans le cas de modèles potentiellement complexes et fortement non linéaires repose sur la décomposition ANOVA et les indices de Sobol'. En particulier, ces derniers permettent de quantifier l'influence de chacun des paramètres sur la réponse du modèle. Dans cette thèse, nous nous intéressons au problème de l'estimation des indices de Sobol'. Dans une première partie, nous réintroduisons de manière rigoureuse des méthodes existantes au regard de l'analyse harmonique discrète sur des groupes cycliques et des tableaux orthogonaux randomisés. Cela nous permet d'étudier les propriétés théoriques de ces méthodes et de les généraliser. Dans un second temps, nous considérons la méthode de Monte Carlo spécifique à l'estimation des indices de Sobol' et nous introduisons une nouvelle approche permettant de l'améliorer. Cette amélioration est construite autour des hypercubes latins et permet de réduire le nombre de simulations nécessaires pour estimer les indices de Sobol' par cette méthode. En parallèle, nous mettons en pratique ces différentes méthodes sur un modèle d'écosystème marin
In the fields of modelization and numerical simulation, simulators generally depend on several input parameters whose impact on the model outputs are not always well known. The main goal of sensitivity analysis is to better understand how the model outputs are sensisitive to the parameters variations. One of the most competitive method to handle this problem when complex and potentially highly non linear models are considered is based on the ANOVA decomposition and the Sobol' indices. More specifically the latter allow to quantify the impact of each parameters on the model response. In this thesis, we are interested in the issue of the estimation of the Sobol' indices. In the first part, we revisit in a rigorous way existing methods in light of discrete harmonic analysis on cyclic groups and randomized orthogonal arrays. It allows to study theoretical properties of this method and to intriduce generalizations. In a second part, we study the Monte Carlo method for the Sobol' indices and we introduce a new approach to reduce the number of simulations of this method. In parallel with this theoretical work, we apply these methods on a marine ecosystem model
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Livres sur le sujet "Sensitivity indices"

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B, Baldwin David J., et Ontario Forest Research Institute, dir. Sensitivity of landscape pattern indices to spatial extent, data resolution, and classification detail in the managed forest of Ontario. Sault Ste. Marie, Ont : Ontario Forest Research Institute, 2001.

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Malik, Waleed Haider. Cultural sensitivity : Judges in indigenous areas. Washington, D.C : World Bank, 2003.

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Kumar, C. Nalin. Sensitivity of India's agri-food exports to the European Union : An institutional perspective. Bangalore : Institute for Social and Economic Change, 2016.

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Mona, Charles, Fort Lewis College. Dept. of Anthropology., Midwest Archeological Center (U.S.) et Fort Carson (Colo.). Directorate of Environmental Compliance and Management., dir. A cultural resource inventory of high- and medium- site sensitivity areas, Fort Carson Military Reservation : El Paso, Fremont, and Pueblo Counties, Colorado, 1998. [Lincoln, Neb : Midwest Archeological Center, 2000.

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Duclos, Jean-Yves, et Luca Tiberti. Multidimensional Poverty Indices. Sous la direction de Matthew D. Adler et Marc Fleurbaey. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780199325818.013.19.

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This chapter reviews and assesses issues involved in the measurement of multidimensional poverty, in particular the soundness of the various “axioms” and properties often imposed on poverty indices. It argues that some of these properties (such as those relating poverty and inequality) may be sound in a unidimensional setting but not so in a multidimensional one. Second, it addresses critically some of the features of recently proposed multidimensional poverty indices, in particular the Multidimensional Poverty Index (MPI) recently put forward by the United Nations Development Program. The MPI suffers from several unattractive features that need to be better understood (given the prominence of the index). The MPI fails in particular to meet all of three properties that one would expect multidimensional poverty indices to obey: continuity, monotonicity, and sensitivity to multiple deprivation. Robustness techniques to address some of the shortcomings of the use of such indices are briefly advocated.
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Facemire, Charles F. Comparison of the sensitivity of electrophoresis and ecological indices for the detection of environmental stress in aquatic ecosystems. 1989.

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Rosik, Piotr. Świat dostępności - metody i komponenty : przykłady analiz empirycznych przestrzeni Polski = The world of accessibility : methods and components : cases of emprical analyses in Poland's space. Instytut Geografii i Przestrzennego Zagospodarowania im. Stanisława Leszczyckiego, Polska Akademia Nauk, 2021. http://dx.doi.org/10.7163/9788361590767.

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Accessibility has many facets. This study focuses on accessibility involving people’s travel, or to be more precise, on the ability to cover the distance from point A (origin) to point B (destination). Accessibility thus defined has its: (1) components (i.e. transport, land-use, individual and temporal components), (2) dimensions (i.e. travel origin and destination, distance decay, restrictions, barriers, mode of transport, extent of study area, socioeconomic and territorial cohesion, and dynamics) and (3) attributes (i.e. affordability, availability, nodal accessibility, and acceptability). The components, dimensions and attributes combine to form the world of accessibility. After having been a subject of academic writing for decades, that world has finally received its own comprehensive volume by Polish author. The book covers its topic in seven chapters. It begins with an introduction, which lays down the objectives and structure of the study and is followed by a chapter covering the definition of accessibility. Chapter 3 is devoted to the methodology of accessibility research. The fourth and longest chapter offers a review of the most important areas of the world of accessibility built around the four components and the dimensions of accessibility. Chapter 5 focuses on the attributes of accessibility, transport exclusion and access equality. Chapter 6 presents the basics of the authors’ own new model of four accessibility factors (network, spatial, travel and individual) developed in the form of a NeST box model. The volume ends with a review of the major threads and considerations of accessibility research in the immediate future, namely: (1) Big Data; (2) distance decay; (3) external spatial effects; (4) sensitivity, criticality and exposure; (5) development of new forms of transport; (6) affordability and equality; (7) long-term effects of the COVID-19 pandemic; (8) comparative analyses and evaluation using accessibility indices.
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Pelto, Joan McAlmond. Field sensitivity of Native American students at Oregon State University, as determined by the group embedded figures test. 1991.

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Weinberg, Jonathan M. Knowledge, Noise, and Curve-Fitting. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198724551.003.0016.

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The psychology of the ‘Gettier effect’ appears robust—but complicated. Contrary to initial reports, more recent and thorough work by several groups of researchers indicates strongly that it is in fact found widely across cultures. Nonetheless, I argue that the pattern of psychological results should not at all be taken to settle the epistemological questions about the nature of knowledge. For the Gettier effect occurs both intermittently and with sensitivity to epistemically irrelevant factors. In short, the effect is noisy. And good principles of model selection indicate that, the noisier one’s data, the more one should prefer simpler curves over those that may be more complicated yet hew closer to the data. While we should not endorse K=JTB at this time, nonetheless the question ‘Is knowledge really just justified true belief?’ ought to be treated as once again in play.
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King, Anna S., dir. Indian Religions : Renaissance and Renewal. Equinox Publishing, 2007. http://dx.doi.org/10.1558/isbn.9781845531690.

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Indian Religions: Renaissance and Renewal, the latest collection of Spalding papers, celebrates the work of Ninian Smart in bringing together papers by some of the most eminent scholars within this field. The papers are concerned with cultural, religious, political or textual exchange and encounter, and therefore in concepts of rupture, revival, restoration, reformation and reformulation. The title of this book comes directly from Professor Klaus Klostermaier’s paper which argues that the real Hindu Renaissance is happening now. However, the title also embraces the contemporary problematic of the study of Indian religions. There cannot ever have been a time when the scholarly study of Indic religions has been under such scrutiny or more politically, culturally and religiously sensitive. The papers in section one urge a major rethinking of academic paradigms. The papers in the second section focus on texts, contexts and ways of understanding. Vastly different in style, period and approach, they nevertheless cumulatively develop sensitivity to textual continuities, to the purposes of commentators and the contemporary creative reinterpretation of texts and their application to real life. The third section is concerned with cultural and religious encounter and exchange, transformation, restoration, revival and reformation. The fourth section is concerned with the performative, experiential and expressive. There are papers on the Hindu imagination and imaginary Hinduisms; religion, the media and a multi-modal future; ritual performance and gender; art and the aesthetic imagination.
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Chapitres de livres sur le sujet "Sensitivity indices"

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Mandel, David, et Giray Ökten. « Randomized Sobol’ Sensitivity Indices ». Dans Springer Proceedings in Mathematics & ; Statistics, 395–408. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-91436-7_22.

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Turnovec, František, et Jacek Mercik. « Sensitivity Analysis of a Priori Power Indices ». Dans Intelligent Information and Database Systems, 464–73. Cham : Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05476-6_47.

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Kucherenko, Sergei, et Shugfang Song. « Derivative-Based Global Sensitivity Measures and Their Link with Sobol’ Sensitivity Indices ». Dans Springer Proceedings in Mathematics & ; Statistics, 455–69. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-33507-0_23.

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Gottschalk, Alexander, Eugene Cornelius et Paul B. Hoffer. « Sensitivity and Efficacy Indices for Oncologic Data Reporting ». Dans Radiolabeled Monoclonal Antibodies for Imaging and Therapy, 139–45. Boston, MA : Springer US, 1988. http://dx.doi.org/10.1007/978-1-4684-5538-0_11.

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Fedotov, A. A., et A. S. Akulova. « Sensitivity of heart rate variability indices for artificially simulated data ». Dans IFMBE Proceedings, 945–49. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-19387-8_230.

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Spiring, Fred. « The Sensitivity of Common Capability Indices to Departures from Normality ». Dans Frontiers in Statistical Quality Control 9, 277–93. Heidelberg : Physica-Verlag HD, 2010. http://dx.doi.org/10.1007/978-3-7908-2380-6_18.

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Obrist, W. D., et W. E. Wilkinson. « Stability and Sensitivity of CBF Indices in the Noninvasive 133Xe Method ». Dans Cerebral Blood Flow and Metabolism Measurement, 30–36. Berlin, Heidelberg : Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-70054-5_4.

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Chervenkov, Hristo, et Valery Spiridonov. « Sensitivity of Selected ETCCDI Climate Indices from the Calculation Method for Projected Future Climate ». Dans Advances in High Performance Computing, 413–27. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-55347-0_35.

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Jain, Rinkesh A., et Darshan B. Rathod. « Line Stability Indices and Contingency Screening by Sensitivity Factors Based Static Voltage Stability Study ». Dans Advances in Intelligent Systems and Computing, 129–38. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1966-2_11.

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Perkins, Kyle, et Worthen N. Hunsaker. « A Comparison of Bayesian and Traditional Indices for Measuring Information Gain Sensitivity in a Cloze Test ». Dans Language Proficiency, 163–71. Boston, MA : Springer US, 1990. http://dx.doi.org/10.1007/978-1-4899-0870-4_17.

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Actes de conférences sur le sujet "Sensitivity indices"

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Todorov, Venelin, et Slavi Georgiev. « An Optimization Technique for Estimating Sobol Sensitivity Indices ». Dans 17th Conference on Computer Science and Intelligence Systems. PTI, 2022. http://dx.doi.org/10.15439/2022f170.

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Algarni, Ayed A. S., et Kankar Bhattacharya. « Novel sensitivity indices based siting of distributed generation resources ». Dans Energy Society General Meeting. IEEE, 2008. http://dx.doi.org/10.1109/pes.2008.4596504.

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Dold, Edward J., et Philip A. Voglewede. « Sensitivity Study With Sobol’ Indices in Planar Multistable Mechanisms ». Dans ASME 2022 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/detc2022-89414.

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Abstract This paper introduces the application of Sobol’ sensitivity indices to the design of toggle mechanisms. Sobol’ indices measure how the variance of the inputs (mechanism parameters) affect the variance of the output (potential energy). The kinematics of the mechanism are calculated to determine the mechanism parameters and potential energy. The indices reveal which parameter has the greatest effect on the variance of the potential energy, pointing designers to the area of the mechanism that should be the focus of improvement. Calculation and interpretation of Sobol’ indices are applied to three examples to show that the results are in line with engineering intuition. The applicability of the indices to any mechanism and their influence on design decisions are also shown. The benefits of the index being normalized are discussed along with methods of reducing computational cost.
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Benidris, Mohammed, et Joydeep Mitra. « Sensitivity analysis of power system reliability indices under emission constraints ». Dans 2014 International Conference on Probabilistic Methods Applied to Power Systems (PMAPS). IEEE, 2014. http://dx.doi.org/10.1109/pmaps.2014.6960650.

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Kala, Zdeněk. « Variance-based sensitivity indices for stochastic models with correlated inputs ». Dans PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON NUMERICAL ANALYSIS AND APPLIED MATHEMATICS 2014 (ICNAAM-2014). AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4913077.

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Kucherenko, Sergei, et Shufang Song. « COMPARISON OF DIFFERENT NUMERICAL ESTIMATORS FOR MAIN EFFECT GLOBAL SENSITIVITY INDICES ». Dans 1st International Conference on Uncertainty Quantification in Computational Sciences and Engineering. Athens : Institute of Structural Analysis and Antiseismic Research School of Civil Engineering National Technical University of Athens (NTUA) Greece, 2015. http://dx.doi.org/10.7712/120215.4296.648.

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Raghavan, Srini H., et Michelle M. Ardeshiri. « Sensitivity analysis of measurement of modulation indices in phase modulated signals ». Dans 2018 IEEE Aerospace Conference. IEEE, 2018. http://dx.doi.org/10.1109/aero.2018.8396646.

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Raghavan, Srini H., et Michelle M. Ardeshiri. « Measurement Sensitivity of Modulation Indices in Telemetry, Tracking and Command Systems ». Dans 2019 IEEE Aerospace Conference. IEEE, 2019. http://dx.doi.org/10.1109/aero.2019.8741863.

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Niewiadomski, Karol, Angel Pena-Quintal, David W. P. Thomas et Sharmila Sumsurooah. « Sensitivity Analysis of Parasitics in Power Electronic Circuit through Sobol’ Indices ». Dans 2021 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC). IEEE, 2021. http://dx.doi.org/10.1109/apemc49932.2021.9597088.

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Yue, Jianpeng, Jaime A. Camelio et Melida Chin. « Product Oriented Sensitivity Analysis for Multi-Station Compliant Assemblies ». Dans ASME 2006 International Manufacturing Science and Engineering Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/msec2006-21077.

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Dimensional variation in assembled products directly affects product performance. To reduce dimensional variation it is necessary that an assembly be robust. A robust assembly is less sensitive to input variation from the product and process components such as incoming parts, subassemblies, fixtures and welding guns. In order to effectively understand the sensitivity of an assembly to input variation, an appropriate set of metrics must be defined. In this paper, three product oriented indices including pattern sensitivity index, component sensitivity index and station sensitivity index are defined. These indices can be utilized to measure the variation influence of a pattern, an individual part and/or component, and components at a particular station to the dimensional quality of a final assembly. Additionally, the relationships among these sensitivity indices are established. Based on these relationships, the ranges of the sensitivity indices are derived. Finally, a case study of a sheet metal assembly is presented and discussed to illustrate the applicability of these metrics.
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Rapports d'organisations sur le sujet "Sensitivity indices"

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Canavan, G. H. Sensitivity of stability indices to dealerting. Office of Scientific and Technical Information (OSTI), mars 1998. http://dx.doi.org/10.2172/663410.

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Canavan, G. H. Sensitivity of stability indices to force uncertainties. Office of Scientific and Technical Information (OSTI), juillet 1997. http://dx.doi.org/10.2172/544701.

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Beauchemin, M., D. Pan et K. B. Fung. Sensitivity of Landscape Indices to Classification Accuracy. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2001. http://dx.doi.org/10.4095/219782.

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Manson, G. K., N. J. Couture et T. S. James. CanCoast 2.0 : data and indices to describe the sensitivity of Canada's marine coasts to changing climate. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2019. http://dx.doi.org/10.4095/314669.

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Gamboa-Estrada, Fredy, et Andrés Sánchez-Jabba. The Effects of Foreign Investor Composition on Colombia´s Sovereign Debt Flows. Banco de la República Colombia, décembre 2022. http://dx.doi.org/10.32468/be.1222.

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Assessing the composition of sovereign debt holders is important because investors’ behavior varies according to distinctive components, including shareholders’ preferences, regulatory constraints, and profitability mandates. To study this issue, we examine the determinants of offshore investments of mutual funds and pension funds, which concentrate Colombia’s outstanding sovereign debt. Our results indicate that mutual funds exhibit considerable sensitivity to shocks in global factors, such as the Federal Funds Rate, sovereign risk, and the composition of financial indices. This contrasts with findings among pension funds, for which we detected no statistically significant effects when examining these factors, underlining the differences in foreign investor behavior that could impact sovereign debt flows within emerging markets.
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Daudelin, Francois, Lina Taing, Lucy Chen, Claudia Abreu Lopes, Adeniyi Francis Fagbamigbe et Hamid Mehmood. Mapping WASH-related disease risk : A review of risk concepts and methods. United Nations University Institute for Water, Environment and Health, décembre 2021. http://dx.doi.org/10.53328/uxuo4751.

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The report provides a review of how risk is conceived of, modelled, and mapped in studies of infectious water, sanitation, and hygiene (WASH) related diseases. It focuses on spatial epidemiology of cholera, malaria and dengue to offer recommendations for the field of WASH-related disease risk mapping. The report notes a lack of consensus on the definition of disease risk in the literature, which limits the interpretability of the resulting analyses and could affect the quality of the design and direction of public health interventions. In addition, existing risk frameworks that consider disease incidence separately from community vulnerability have conceptual overlap in their components and conflate the probability and severity of disease risk into a single component. The report identifies four methods used to develop risk maps, i) observational, ii) index-based, iii) associative modelling and iv) mechanistic modelling. Observational methods are limited by a lack of historical data sets and their assumption that historical outcomes are representative of current and future risks. The more general index-based methods offer a highly flexible approach based on observed and modelled risks and can be used for partially qualitative or difficult-to-measure indicators, such as socioeconomic vulnerability. For multidimensional risk measures, indices representing different dimensions can be aggregated to form a composite index or be considered jointly without aggregation. The latter approach can distinguish between different types of disease risk such as outbreaks of high frequency/low intensity and low frequency/high intensity. Associative models, including machine learning and artificial intelligence (AI), are commonly used to measure current risk, future risk (short-term for early warning systems) or risk in areas with low data availability, but concerns about bias, privacy, trust, and accountability in algorithms can limit their application. In addition, they typically do not account for gender and demographic variables that allow risk analyses for different vulnerable groups. As an alternative, mechanistic models can be used for similar purposes as well as to create spatial measures of disease transmission efficiency or to model risk outcomes from hypothetical scenarios. Mechanistic models, however, are limited by their inability to capture locally specific transmission dynamics. The report recommends that future WASH-related disease risk mapping research: - Conceptualise risk as a function of the probability and severity of a disease risk event. Probability and severity can be disaggregated into sub-components. For outbreak-prone diseases, probability can be represented by a likelihood component while severity can be disaggregated into transmission and sensitivity sub-components, where sensitivity represents factors affecting health and socioeconomic outcomes of infection. -Employ jointly considered unaggregated indices to map multidimensional risk. Individual indices representing multiple dimensions of risk should be developed using a range of methods to take advantage of their relative strengths. -Develop and apply collaborative approaches with public health officials, development organizations and relevant stakeholders to identify appropriate interventions and priority levels for different types of risk, while ensuring the needs and values of users are met in an ethical and socially responsible manner. -Enhance identification of vulnerable populations by further disaggregating risk estimates and accounting for demographic and behavioural variables and using novel data sources such as big data and citizen science. This review is the first to focus solely on WASH-related disease risk mapping and modelling. The recommendations can be used as a guide for developing spatial epidemiology models in tandem with public health officials and to help detect and develop tailored responses to WASH-related disease outbreaks that meet the needs of vulnerable populations. The report’s main target audience is modellers, public health authorities and partners responsible for co-designing and implementing multi-sectoral health interventions, with a particular emphasis on facilitating the integration of health and WASH services delivery contributing to Sustainable Development Goals (SDG) 3 (good health and well-being) and 6 (clean water and sanitation).
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Hamill, Daniel D., Jeremy J. Giovando, Chandler S. Engel, Travis A. Dahl et Michael D. Bartles. Application of a Radiation-Derived Temperature Index Model to the Willow Creek Watershed in Idaho, USA. U.S. Army Engineer Research and Development Center, août 2021. http://dx.doi.org/10.21079/11681/41360.

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The ability to simulate snow accumulation and melting processes is fundamental to developing real-time hydrological models in watersheds with a snowmelt-dominated flow regime. A primary source of uncertainty with this model development approach is the subjectivity related to which historical periods to use and how to combine parameters from multiple calibration events. The Hydrologic Engineering Center, Hydrological Modeling System, has recently implemented a hybrid temperature index (TI) snow module that has not been extensively tested. This study evaluates a radiatative temperature index (RTI) model’s performance relative to the traditional air TI model. The TI model for Willow Creek performed reasonably well in both the calibration and validation years. The results of the RTI calibration and validation simulations resulted in additional questions related to how best to parameterize this snow model. An RTI parameter sensitivity analysis indicates that the choice of calibration years will have a substantial impact on the parameters and thus the streamflow results. Based on the analysis completed in this study, further refinement and verification of the RTI model calculations are required before an objective comparison with the TI model can be completed.
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Fluhr, Robert, et Maor Bar-Peled. Novel Lectin Controls Wound-responses in Arabidopsis. United States Department of Agriculture, janvier 2012. http://dx.doi.org/10.32747/2012.7697123.bard.

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Innate immune responses in animals and plants involve receptors that recognize microbe-associated molecules. In plants, one set of this defense system is characterized by large families of TIR–nucleotide binding site–leucine-rich repeat (TIR-NBS-LRR) resistance genes. The direct interaction between plant proteins harboring the TIR domain with proteins that transmit and facilitate a signaling pathway has yet to be shown. The Arabidopsis genome encodes TIR-domain containing genes that lack NBS and LRR whose functions are unknown. Here we investigated the functional role of such protein, TLW1 (TIR LECTIN WOUNDRESPONSIVE1). The TLW1 gene encodes a protein with two domains: a TIR domain linked to a lectin-containing domain. Our specific aim in this proposal was to examine the ramifications of the TL1-glycan interaction by; A) The functional characterization of TL1 activity in the context of plant wound response and B) Examine the hypothesis that wounding induced specific polysaccharides and examine them as candidates for TL-1 interactive glycan compounds. The Weizmann group showed TLW1 transcripts are rapidly induced by wounding in a JA-independent pathway and T-DNA-tagged tlw1 mutants that lack TLW1 transcripts, fail to initiate the full systemic wound response. Transcriptome methodology analysis was set up and transcriptome analyses indicates a two-fold reduced level of JA-responsive but not JA-independent transcripts. The TIR domain of TLW1 was found to interact directly with the KAT2/PED1 gene product responsible for the final b-oxidation steps in peroxisomal-basedJA biosynthesis. To identify potential binding target(s) of TL1 in plant wound response, the CCRC group first expressed recombinant TL1 in bacterial cells and optimized conditions for the protein expression. TL1 was most highly expressed in ArcticExpress cell line. Different types of extraction buffers and extraction methods were used to prepare plant extracts for TL1 binding assay. Optimized condition for glycan labeling was determined, and 2-aminobenzamide was used to label plant extracts. Sensitivity of MALDI and LC-MS using standard glycans. THAP (2,4,6- Trihydroxyacetophenone) showed minimal background peaks at positive mode of MALDI, however, it was insensitive with a minimum detection level of 100 ng. Using LC-MS, sensitivity was highly increased enough to detect 30 pmol concentration. However, patterns of total glycans displayed no significant difference between different extraction conditions when samples were separated with Dionex ICS-2000 ion chromatography system. Transgenic plants over-expressing lectin domains were generated to obtain active lectin domain in plant cells. Insertion of the overexpression construct into the plant genome was confirmed by antibiotic selection and genomic DNA PCR. However, RT-PCR analysis was not able to detect increased level of the transcripts. Binding ability of azelaic acid to recombinant TL1. Azelaic acid was detected in GST-TL1 elution fraction, however, DHB matrix has the same mass in background signals, which needs to be further tested on other matrices. The major findings showed the importance of TLW1 in regulating wound response. The findings demonstrate completely novel and unexpected TIR domain interactions and reveal a control nexus and mechanism that contributes to the propagation of wound responses in Arabidopsis. The implications are to our understanding of the function of TIR domains and to the notion that early molecular events occur systemically within minutes of a plant sustaining a wound. A WEB site (http://genome.weizmann.ac.il/hormonometer/) was set up that enables scientists to interact with a collated plant hormone database.
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Ohad, Itzhak, et Himadri Pakrasi. Role of Cytochrome B559 in Photoinhibition. United States Department of Agriculture, décembre 1995. http://dx.doi.org/10.32747/1995.7613031.bard.

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The aim of this research project was to obtain information on the role of the cytochrome b559 in the function of Photosystem-II (PSII) with special emphasis on the light induced photo inactivation of PSII and turnover of the photochemical reaction center II protein subunit RCII-D1. The major goals of this project were: 1) Isolation and sequencing of the Chlamydomonas chloroplast psbE and psbF genes encoding the cytochrome b559 a and b subunits respectively; 2) Generation of site directed mutants and testing the effect of such mutation on the function of PSII under various light conditions; 3) To obtain further information on the mechanism of the light induced degradation and replacement of the PSII core proteins. This information shall serve as a basis for the understanding of the role of the cytochrome b559 in the process of photoinhibition and recovery of photosynthetic activity as well as during low light induced turnover of the D1 protein. Unlike in other organisms in which the psbE and psbF genes encoding the a and b subunits of cytochrome b559, are part of an operon which also includes the psbL and psbJ genes, in Chlamydomonas these genes are transcribed from different regions of the chloroplast chromosome. The charge distribution of the derived amino-acid sequences of psbE and psbF gene products differs from that of the corresponding genes in other organisms as far as the rule of "positive charge in" is concerned relative to the process of the polypeptide insertion in the thylakoid membrane. However, the sum of the charges of both subunits corresponds to the above rule possibly indicating co-insertion of both subunits in the process of cytochrome b559 assembly. A plasmid designed for the introduction of site-specific mutations into the psbF gene of C. reinhardtii. was constructed. The vector consists of a DNA fragment from the chromosome of C. reinhardtii which spans the region of the psbF gene, upstream of which the spectinomycin-resistance-conferring aadA cassette was inserted. This vector was successfully used to transform wild type C. reinhardtii cells. The spectinomycin resistant strain thus obtained can grow autotrophically and does not show significant changes as compared to the wild-type strain in PSII activity. The following mutations have been introduced in the psbF gene: H23M; H23Y; W19L and W19. The replacement of H23 involved in the heme binding to M and Y was meant to permit heme binding but eventually alter some or all of the electron transport properties of the mutated cytochrome. Tryptophane W19, a strictly conserved residue, is proximal to the heme and may interact with the tetrapyrole ring. Therefore its replacement may effect the heme properties. A change to tyrosine may have a lesser affect on the potential or electron transfer rate while a replacement of W19 by leucine is meant to introduce a more prominent disturbance in these parameters. Two of the mutants, FW19L and FH23M have segregated already and are homoplasmic. The rest are still grown under selection conditions until complete segregation will be obtained. All mutants contain assembled and functional PSII exhibiting an increased sensitivity of PSII to the light. Work is still in progress for the detailed characterization of the mutants PSII properties. A tobacco mutant, S6, obtained by Maliga and coworkers harboring the F26S mutation in the b subunit was made available to us and was characterized. Measurements of PSII charge separation and recombination, polypeptide content and electron flow indicates that this mutation indeed results in light sensitivity. Presently further work is in progress in the detailed characterization of the properties of all the above mutants. Information was obtained demonstrating that photoinactivation of PSII in vivo initiates a series of progressive changes in the properties of RCII which result in an irreversible modification of the RCII-D1 protein leading to its degradation and replacement. The cleavage process of the modified RCII-D1 protein is regulated by the occupancy of the QB site of RCII by plastoquinone. Newly synthesized D1 protein is not accumulated in a stable form unless integrated in reassembled RCII. Thus the degradation of the irreversibly modified RCII-D1 protein is essential for the recovery process. The light induced degradation of the RCII-D1 protein is rapid in mutants lacking the pD1 processing protease such as in the LF-1 mutant of the unicellular alga Scenedesmus obliquus. In this case the Mn binding site of PSII is abolished, the water oxidation process is inhibited and harmful cation radicals are formed following light induced electron flow in PSII. In such mutants photo-inactivation of PSII is rapid, it is not protected by ligands binding at the QB site and the degradation of the inactivated RCII-D1 occurs rapidly also in the dark. Furthermore the degraded D1 protein can be replaced in the dark in absence of light driven redox controlled reactions. The replacement of the RCII-D1 protein involves the de novo synthesis of the precursor protein, pD1, and its processing at the C-terminus end by an unknown processing protease. In the frame of this work, a gene previously isolated and sequenced by Dr. Pakrasi's group has been identified as encoding the RCII-pD1 C-terminus processing protease in the cyanobacterium Synechocystis sp. PCC 6803. The deduced sequence of the ctpA protein shows significant similarity to the bovine, human and insect interphotoreceptor retinoid-binding proteins. Results obtained using C. reinhardtii cells exposes to low light or series of single turnover light flashes have been also obtained indicating that the process of RCII-D1 protein turnover under non-photoinactivating conditions (low light) may be related to charge recombination in RCII due to back electron flow from the semiquinone QB- to the oxidised S2,3 states of the Mn cluster involved in the water oxidation process.
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