Search results for " Stab"

Positive l<inf>1</inf> observer design for positive switched systems with time-varying delays via delta operator approach

2014

Futures pricing in electricity markets based on stable CARMA spot models

2012

We present a new model for the electricity spot price dynamics, which is able to capture seasonality, low-frequency dynamics and the extreme spikes in the market. Instead of the usual purely deterministic trend we introduce a non-stationary independent increments process for the low-frequency dynamics, and model the large uctuations by a non-Gaussian stable CARMA process. The model allows for analytic futures prices, and we apply these to model and estimate the whole market consistently. Besides standard parameter estimation, an estimation procedure is suggested, where we t the non-stationary trend using futures data with long time until delivery, and a robust L 1 -lter to nd the states of …

A fully adaptive wavelet algorithm for parabolic partial differential equations

2001

We present a fully adaptive numerical scheme for the resolution of parabolic equations. It is based on wavelet approximations of functions and operators. Following the numerical analysis in the case of linear equations, we derive a numerical algorithm essentially based on convolution operators that can be efficiently implemented as soon as a natural condition on the space of approximation is satisfied. The algorithm is extended to semi-linear equations with time dependent (adapted) spaces of approximation. Numerical experiments deal with the heat equation as well as the Burgers equation.

Weighting non-covalent forces in the molecular recognition of C60. Relevance of concave–convex complementarity

2008

The relative contributions of several weak intermolecular forces to the overall stability of the complexes formed between structurally related receptors and [60]fullerene are compared, revealing a discernible contribution from concave–convex complementarity. Viruela Martin, Pedro Manuel, Pedro.M.Viruela@uv.es ; Viruela Martin, Rafael, Rafael.Viruela@uv.es ; Orti Guillen, Enrique, Enrique.Orti@uv.es

Pricing to market behaviour in European car markets

2003

Abstract This paper investigates PTM behaviour in European car markets for a period of great interest (1993–98), taking into account the role of invoicing currency. The results indicate that local currency price stability is a strong and pervasive phenomenon across products independently of the invoicing currency. The paper offers robustness checks, tests and arguments that justify the interpretation of this finding, at least in part, as evidence of PTM. It implies the existence of market segmentation and price discrimination, despite the completion of the single market programme on 1 January 1993.

A History of the Pharmacological Treatment of Bipolar Disorder.

2018

In this paper, the authors review the history of the pharmacological treatment of bipolar disorder, from the first nonspecific sedative agents introduced in the 19th and early 20th century, such as solanaceae alkaloids, bromides and barbiturates, to John Cade’s experiments with lithium and the beginning of the so-called “Psychopharmacological Revolution” in the 1950s. We also describe the clinical studies and development processes, enabling the therapeutic introduction of pharmacological agents currently available for the treatment of bipolar disorder in its different phases and manifestations. Those drugs include lithium salts, valproic acid, carbamazepine, new antiepilep…

Optimal Flight Path Determination in Turbulent Air: A Modified EKF Approach

2017

By using the Extended Kalman Filter an accurate path following in turbulent air is performed. The procedure employs simultaneously two different EKFs: the first one estimates disturbances, the second one affords to determine the necessary controls displacements for rejecting those ones. To tune the EKFs an optimization algorithm has been designed to automatically determine Process Noise Covariance and Measurement Noise Covariance matrices. The first filter, by using instrumental measurements gathered in turbulent air, estimates wind components. The second one obtains command laws able to follow the desired flight path. To perform this task aerodynamic coefficients have been modified. Such a…

Robust fault detection filter design for a class of linear systems with mixed time-varying delays and nonlinear perturbations

2009

In this note, the problem of robust fault detection filter (RFDF) design for a class of linear systems subjected to some nonlinear perturbations and mixed neutral and discrete time-varying delays is investigated based on an H ∞ performance condition. By introducing a descriptor technique, using Lyapunov-Krasovskii functional and a suitable change of variables, new required sufficient conditions are established in terms of delay-dependent linear matrix inequalities (LMIs) to synthesize the residual generation scheme. Based on Luenberger type observers, the explicit expression of the filters is derived for the fault such that both asymptotic stability and a prescribed level of disturbance att…

Income structure, profitability and risk in the European banking sector: The impact of the crisis

2017

This study sets out to analyse whether the effect of the income structure on the risk and profitability of European banks has changed as a result of the crisis and if it varies according to banks’ specialisation in a particular type of banking business. To do so, it estimates the income structure over the period 2002–2012 using data for a panel of European banks. The study also examines if there are differences between investment-oriented banks and banks specialising in financial intermediation in terms of the effect of income structure on risk and profitability. Our findings show that an increase in the share of non-interest income has a negative impact on profitability, although the effec…

Quantifying Structural Subsidy Values for Systemically Important Financial Institutions

2013

Abstract Claimants to Systemically Important Financial Institutions (SIFIs) would receive transfers when governments are forced into bailouts. Ex ante, this bailout expectation lowers SIFIs’ daily funding costs. The funding cost advantage reflects both the structural level of the government support and the time-varying market valuation for such a support. Based on a large worldwide sample of banks, we estimate the value of the structural subsidy, by exploiting expectations of state support embedded in credit ratings and by applying the long-run average value of the rating bonus. The value of the structural subsidy was already sizable, 60 basis points (bp), as of the end-2007, before the cri…