Search results for "Measure"
showing 10 items of 4687 documents
Theoretical and Pragmatic Approaches of Undeclared Work in Romania
2014
Abstract Undeclared work in Romania is a very widespread phenomenon. The published information about the employment relationship worries us, having regard to the damage recorded by undeclared work. For this reason, without claiming a comprehensive approach, through this article we try to give answer to questions such as: What is undeclared work and how it is manifested in Romania? What is the level of undeclared work in Romania? What are the main causes of undeclared work? What measures can be taken to prevent, detect and stop undeclared work? What is the experience of other countries to combat undeclared work?
Shock-capturing schemes: high accuracy versus total-variation boundedness
2007
In this reseach work we analyze the total variation growth of some high order accurate reconstruction procedures used for the design of shock capturing schemes. This study allows to measure how oscillatory a high order accurate method is in terms of the basic elementary function chosen to increase the order of accuracy. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal passive-damping design using a decentralized velocity-feedback H-infinity approach
2012
In this work, a new strategy to design passive energy dissipation systems for vibration control of large structures is presented. The method is based on the equivalence between passive damping systems and fully decentralized static velocity-feedback controllers. This equivalence allows to take advantage of recent developments in static output-feedback control design to formulate the passive-damping design as a single optimization problem with Linear Matrix Inequality constraints. To illustrate the application of the proposed methodology, a passive damping system is designed for the seismic protection of a five-story building with excellent results. Peer Reviewed
A COMPARISON BETWEEN COMBUSTION PHASE INDICATORS FOR OPTIMAL SPARK TIMING
2008
The closed-loop control of internal combustion engine spark timing may be accomplished by means of a combustion phase indicator, i.e., a parameter, derived from in-cylinder pressure analysis, whose variation is mainly referable to combustion phase shift and assumes a fixed reference value under optimal spark timing operation. The aim of the present work is a comparison between different combustion phase indicators, focusing on the performance attainable by a feedback spark timing control, which uses the indicator as pilot variable. An extensive experimental investigation has been carried out, verifying the relationship between indicators’ optimal values and the main engine running parameter…
Scenery Flow, Conical Densities, and Rectifiability
2015
We present an application of the recently developed ergodic theoretic machinery on scenery flows to a classical geometric measure theoretic problem in Euclidean spaces. We also review the enhancements to the theory required in our work. Our main result is a sharp version of the conical density theorem, which we reduce to a question on rectifiability.
The Performance of the Gradient-Like Influence Measure in Generalized Linear Mixed Models
2015
A gradient-like statistic, recently introduced as an influence measure, has been proven to work well in large sample, thanks to its asymptotic properties. In this work, through small-scale simulation schemes, the performance of such a diagnostic measure is further investigated in terms of concordance with the main influence measures used for outlier identification. The simulation studies are performed by using generalized linear mixed models (GLMMs).
Some insights on the description of gradient elution in reversed-phase liquid chromatography
2014
The so-called "fundamental equation for gradient elution" has been used for modeling the retention in gradient elution. In this approach, the instantaneous retention factor (k) is expressed as a function of the change in the modifier content (φ(ts )), ts being the time the solute has spent in the stationary phase. This approach can only be applied at constant flow rate and with gradients where the elution strength depends on the column length following a f(t-l/u) function, u being the linear mobile phase flow rate, and l the distance from the column inlet to the location where the solute is at time t measured from the beginning of the gradient. These limitations can be solved by using the h…
About the reliability, efficiency, and meaning of the error estimates of a LAOCOON3-type NMR analysis system
1977
Abstract The statistical error estimates of a LAOCOON3-type system are tested. The analyzabilities of a spectrum and spectral parameters are described by a new measure. The variation in the uncertainties of the parameters can be explained by correlation coefficients. According to the calculations made, the error estimates are normally quite reliable if the accuracy of the observed spectrum is known. In some cases the Newton-Raphson type of iteration does not converge or the confidence limits of the parameters are enormous or both; an example is discussed. It seems clear that one cannot avoid differing uncertainties of the parameters by changing the method of analysis, or that one can avoid …
Electrical conductivity as a state indicator for the start-up period of anaerobic fixed-bed reactors.
2016
The aim of this work was to analyse the applicability of electrical conductivity sensors for on-line monitoring the start-up period of an anaerobic fixed-bed reactor. The evolution of bicarbonate concentration and methane production rate was analysed. Strong linear relationships between electrical conductivity and both bicarbonate concentration and methane production rate were observed. On-line estimations of the studied parameters were carried out in a new start-up period by applying simple linear regression models, which resulted in a good concordance between both observed and predicted values. Electrical conductivity sensors were therefore identified as an interesting method for monitori…
The impact of adult attachment style on organizational commitment and adult attachment in the workplace
2015
International audience; Adult attachment style has only recently been considered as having a role in explaining work behavior. The present research aimed to explore the impact of adult attachment style, assessed by the Adult Attachment Interview (AAI), on organizational commitment (OC) and on adult attachment in the workplace (AAW). We hypothesized that a secure attachment style would be positively related to affective and normative commitment, while preoccupied and avoidant styles would be negatively related to affective commitment; we also hypothesized that there would be a correspondence between the AAI categories and the AAW dimensions. Using the AAI categories as group variable, analys…