Search results for " Error."
showing 10 items of 1034 documents
Plauto. Menecmi
2020
Due fratelli gemelli, una moglie ricca e una giovane amante, un servo fedele e un parassita inaffidabile, un banchetto segreto e un mantello rubato: sono questi gli ingredienti che danno vita alla commedia dei Menaechmi, che si struttura attorno allo schema dell’equivoco. I due Menecmi del titolo, identici per uno strano gioco del destino perfino nel nome, sono sulla scena – quasi paradossalmente – l’uno ignaro dell’altro e, in tal modo, generano confusione tra i vari personaggi della pièce, alimentando, con malintesi e ambiguità, una divertente serie di gag in una straordinaria comedy of errors. Two twin brothers, a rich wife and a young lover, a faithful servant and an unreliable parasite…
Finite element approximation of vector fields given by curl and divergence
1981
In this paper a finite element approximation scheme for the system curl is considered. The use of pointwise approximation of the boundary condition leads to a nonconforming method. The error estimate is proved and numerically tested.
On the numerical solution of the distributed parameter identification problem
1991
A new error estimate is derived for the numerical identification of a distributed parameter a(x) in a two point boundary value problem, for the case that the finite element method and the fit-to-data output-least-squares technique are used for the identifications. With a special weighted norm, we get a pointwise estimate. Prom the error estimate and also from the numerical tests, we find that if we decrease the mesh size, the maximum error between the identified parameter and the true parameter will increase. In order to improve the accuracy, higher order finite element spaces should be used in the approximations.
Imprisoned But Innocent: Wrongful Convictions and Imprisonments in Germany, 1990-2016
2019
Although in the United States wrongful convictions and imprisonments are a major public and scientific concern, this topic has been largely ignored in Germany for decades. The present article offers for the first time an overview of all accessible German cases of successful retrials involving convicted persons who served a prison sentence since 1990. The data refer to 31 wrongfully convicted persons in 29 independent cases. Although the largest group consists of cases of false allegations, some of the wrongly convicted were considered not guilty by reason of insanity, and a few wrongful convictions occurred because of eyewitness misidentification and false confessions. In addition, incorre…
Improved accuracy of environmentally relevant parameter estimates derived from biodegradation assays.
2019
Biodegradation assays involve both biodegradation and analytical processes which can be affected by systematic errors, among others. These errors can affect all the environmentally relevant parameters related to biodegradability, enantioselectivity (in the case of chiral compounds), kinetic parameters and persistence of chemicals. However, such impacts have never been well-characterized. In this work, calculations and models used for a long time are studied by simulating systematic errors at the 5% level, which affect independently the analytical calibration step and the biodegradation process. The impact of these errors is also compared with those obtained from an alternative approach: rec…
A more cost-effective geomatic approach to modelling PM10 dispersion across Europe
2014
International audience; PM10 concentrations in most major European cities exceed the limits set by the European Directive and are expected to continue to do so in the coming years. Moreover, PM10s can be transported over long distances impacting air quality, public health and ecosystem functionality far from their sources of emission. Modelling remains one of the only options for tracking PM10 deposition in remote areas with no monitoring stations. Even so, air pollution models based on atmospheric physics usually imply substantial economic, logistical and computational investment. In this work, we present a new geomatic approach to modelling mean annual PM10 concentrations across Europe. O…
Relationship between UVB and broadband solar radiation in Spain
2014
The daily values of UVB irradiation (290–315 nm), IUVB, and the broadband total irradiation (300–2800 nm), IT, measured on a horizontal plane have been correlated for the period 2000–2008 at 16 measurement sites in Spain. The results have been compared with the daily experimental values registered at the same sites during the period 2009–2011. The coefficients of determination R2 obtained by applying a linear regression are higher than 0.88 for all sites and increase to 0.94 when using a quadratic regression. When all data are considered together, the values of R2 are 0.91 and 0.97 for the linear and quadratic regressions, respectively. Three different clearness indices, which are dimension…
On the finite element approximation for maxwell’s problem in polynomial domains of the plane
1981
The time-harmonic Maxwell boundary value problem in polygonal domains of R2 is considered. The behaviour of the solution in the neighbourhood of nonregular boundary points is given and asymptotic error estimates in L2- and in curl-div-norm for a finite element approximation of the solution are derived
Polynomial Regression and Measurement Error
2020
Many of the phenomena of interest in information systems (IS) research are nonlinear, and it has consequently been recognized that by applying linear statistical models (e.g., linear regression), we may ignore important aspects of these phenomena. To address this issue, IS researchers are increasingly applying nonlinear models to their datasets. One popular analytical technique for the modeling and analysis of nonlinear relationships is polynomial regression, which in its simplest form fits a "U-shaped" curve to the data. However, the use of polynomial regression can be problematic when the independent variables are contaminated with measurement error, and the implications of error can be m…
Principal polynomial analysis for remote sensing data processing
2011
Inspired by the concept of Principal Curves, in this paper, we define Principal Polynomials as a non-linear generalization of Principal Components to overcome the conditional mean independence restriction of PCA. Principal Polynomials deform the straight Principal Components by minimizing the regression error (or variance) in the corresponding orthogonal subspaces. We propose to use a projection on a series of these polynomials to set a new nonlinear data representation: the Principal Polynomial Analysis (PPA). We prove that the dimensionality reduction error in PPA is always lower than in PCA. Lower truncation error and increased independence suggest that unsupervised PPA features can be b…