Search results for " uncertainties"
showing 10 items of 22 documents
First-order linear differential equations whose data are complex random variables: Probabilistic solution and stability analysis via densities
2022
[EN] Random initial value problems to non-homogeneous first-order linear differential equations with complex coefficients are probabilistically solved by computing the first probability density of the solution. For the sake of generality, coefficients and initial condition are assumed to be absolutely continuous complex random variables with an arbitrary joint probability density function. The probability of stability, as well as the density of the equilibrium point, are explicitly determined. The Random Variable Transformation technique is extensively utilized to conduct the overall analysis. Several examples are included to illustrate all the theoretical findings.
Uncertainties and Risks in the Implementation of an E-Learning Information Systems Project in a Higher-Learning Environment: Viewpoints from Estonia
2005
This paper investigates the sorts of risks and uncertainties inherent in implementing an e-learning information systems project in Estonia. The study uses a variation of the Delphi study in eliciting the risk factors or items from experienced top management professionals within the organisation. The main objective of the study is to identify the uncertainties or risks in the implementation of the systems, using the viewpoint of Estonia, which is an emerging economy. The findings of the work indicate that wrong development strategy, staff volatility, change in top management and lack of funding are amongst the top risk factors in implementing e-learning in Estonia. On the other hand, risks …
On the Limit Behaviour of Moment Resisting Connections Under Uncertainties
2021
Abstract Moment resisting connections are mainly designed to transfer bending moments and shear forces. Generally speaking, the design strength of a moment resisting connection can be classified as full-strength (moment capacity of the connection equal to or greater than that of the connected member) or partial-strength (the moment capacity of the connection less than that of the connected member). Similar remarks can be made regarding the stiffness defining connection rigid or semi-rigid if compared to the stiffness of the connected member. In the past, full-strength connections have been widely adopted especially in moment resisting frames and their structural performance relied on the pr…
Finite-Time Hâ Filtering for T-S Fuzzy Discrete-Time Systems with Time-Varying Delay and Norm-Bounded Uncertainties
2015
In this paper, we investigate the filtering problem of discrete-time Takagi–Sugeno (T–S) fuzzy uncertain systems subject to time-varying delays. A reduced-order filter is designed. With the augmentation technique, a filtering error system with delayed states is obtained. In order to deal with time delays in system states, the filtering error system is first transformed into two interconnected subsystems. By using a two-term approximation for the time-varying delay, sufficient delay-dependent conditions of finite-time boundedness and $H_{\infty }$ performance of the filtering error system are derived with the Lyapunov function. Based on these conditions, the filter design methods are propose…
Robust control of continuous-time systems with state-dependent uncertainties and its application to electronic circuits
2014
In this paper, the problems of robust stability and stabilization are investigated for a class of continuous-time uncertain systems. The uncertainties in the model are state-dependent and belong to a polytopic convex set, as can be found in many electronic circuits and some other applications. The global asymptotic stability conditions for such systems are first established by the classic common quadratic Lyapunov function approach. To reduce conservativeness, a particular class of nonquadratic parameter-dependent Lyapunov functions is introduced, by which improved robust stability conditions for the underlying systems are also derived. Based on the stability criteria, a static output feedb…
The 2017 Assisi Think Tank Meeting on rectal cancer: A positioning paper
2019
BACKGROUND AND PURPOSES: To describe current practice in the management of rectal cancer, to identify uncertainties that usually arise in the multidisciplinary team (MDT)'s discussions ('grey zones') and propose next generation studies which may provide answers to them. MATERIALS AND METHODS: A questionnaire on the areas of controversy in managing T2, T3 and T4 rectal cancer was drawn up and distributed to the Rectal-Assisi Think Tank Meeting (ATTM) Expert European Board. Less than 70% agreement on a treatment option was indicated as uncertainty and selected as a 'grey zone'. Topics with large disagreement were selected by the task force group for discussion at the Rectal-ATTM. RESULTS: The…
"Table 15" of "Search for events with large missing transverse momentum, jets, and at least two tau leptons in 7 TeV proton-proton collision data wit…
2012
The relative systematic uncertainty from the selection, theoretical and statistical uncertainities and their combined values.
"Table 2" of "Comprehensive measurements of $t$-channel single top-quark production cross sections at $\sqrt{s} = 7$ TeV with the ATLAS detector"
2021
Detailed list of the contribution of each source of uncertainty to the total uncertainty on the measured values of $\sigma(tq)$, $\sigma(\bar{t}q)$, $R_t$, and $\sigma(tq+\bar{t}q)$. The evaluation of the systematic uncertainties has a statistical uncertainty of $0.3\,\%$. Uncertainties contributing less than $1.0\,\%$ are marked with "$<1$" in the paper. To provide numerical values for this table in HEPdata, these uncertainties are approximated with $\pm 0.5\,\%$. This approximation is applied to all measurements for the following uncertainties$:$ JES statistical, JES physics modeling, JES mixed detector and modeling, JES close-by-jets, JES pileup, $b$-JES, jet vertex fraction, mistag e…
A sliding mode approach to H∞ synchronization of master–slave time-delay systems with Markovian jumping parameters and nonlinear uncertainties
2012
Author's version of an article published in the journal: Journal of the Franklin Institute. Also available from the publisher at: http://dx.doi.org/10.1016/j.jfranklin.2011.09.015 In this paper, a sliding-mode approach is proposed for exponential H∞ synchronization problem of a class of masterslave time-delay systems with both discrete and distributed time-delays, norm-bounded nonlinear uncertainties and Markovian switching parameters. Using an appropriate LyapunovKrasovskii functional, some delay-dependent sufficient conditions and a synchronization law, which include the masterslave parameters are established for designing a delay-dependent mode-dependent sliding mode exponential H∞ synch…
Parameters analysis influencing 3D measurement without contact by laser scanner to establish a local correction procedure
2007
International audience; The techniques of measuring without contact by laser scanning allows acquisition of a large number of points, at a very high rate speed ; nevertheless with less precision than the one obtained by classical techniques of measuring with contact. We present in this article the research and the experimental analysis of the influential parameters on the precision of the measure by laser sensor without contact. Firstly, a methodology of correction of the relative uncertainties in the conditions of the measuring laser is presented. Then, we apply it to a typical part and compare the results to those obtained by a classical procedure of measuring with a contact sensor. We fi…