Refine my results

Language

  • English (4'141) disable the filter

Keyword

Université de Fribourg

Perturbations to astronomical observations at the European Southern Observatory's very large telescope site in Paranal, Chile: analyses of climatological causes

Beniston, Martin ; Casals, Paula ; Sarazin, Marc S.

In: Theoretical and Applied Climatology, 2002, vol. 73(3-4), p. 133-150

A study has been conducted to assess the reasons for a significant decrease in the astronomic observing period since the Very Large Telescope of ESO (the European Southern Observatory) went into operation in 1998. Following a multi-year monitoring of meteorological parameters at the site of the ESO telescope in Paranal (northern Chile), the optimal climatic conditions observed there prior to the...

Université de Fribourg

Nonlinearities, feedbacks and critical thresholds within the earth's climate system

Rial, José A. ; Pielke, Roger A. ; Beniston, Martin ; Claussen, Martin ; Canadell, Josep ; Cox, Peter ; Held, Hermann ; Noblet-Ducoudré, Nathalie de ; Prinn, Ronald ; Reynolds, James F. ; Salas, José D.

In: Climatic Change, 2004, vol. 65, p. 11

The Earth's climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm. While this is widely accepted, there is a relatively poor understanding of the different types of nonlinearities, how they manifest under various conditions, and whether they reflect a climate system...

Università della Svizzera italiana

Constrained nonparametric dependence with application in finance

Gagliardini, Patrick ; Barone-Adesi, Giovanni (Dir.)

Thèse de doctorat : Università della Svizzera italiana, 2003 ; 2003ECO002.

The developments of financial theory in the last decades have shown that one of the most fundamental topics in Finance is the specification of dependence between different risk variables. Empirical evidence on financial time series (such as returns, interest rates, or exchange rates) as well as recent developments in risk management (such as the analysis of dependence between default risks of...

Université de Fribourg

Tracing the decision maker

Schulte-Mecklenbeck, Michael ; Huber, Oswald (Dir.) ; Kühberger, Anton (Codir.)

Thèse de doctorat : Université de Fribourg, 2005.

This thesis focuses on two themes: a methodological and a decision making one. The methodological part introduces the development of a computerized information search tool. The program, called WebDiP (Web Decision Processes), enables the researcher to track participants while they are searching for information in a database. An experiment can be done either in the laboratory or on the Web. The...

Università della Svizzera italiana

Hedging and risk measurement for option portfolios

Fierli, Francesco ; Barone-Adesi, Giovanni (Dir.)

Thèse de doctorat : Università della Svizzera italiana, 2004 ; 2004ECO005.

In the first part of this work we address the problem of parameter misspecification in a generic class of stochastic volatility models. We extend the approach proposed by Avellaneda, Levy and Paràs (1995) (hereafter ALP) by moving from a framework with uncertain volatility to the uncertainty on volatility process parameters. We assume that parameter values of the stochastic volatility model are...

Université de Fribourg

The high-resolution stratigraphic architecture and evolution of the Burdigalian carbonate-siliciclastic sedimentary systems of the Mut Basin, Turkey

Bassant, Philip ; Strasser, Andreas (Dir.)

Thèse de doctorat : Université de Fribourg, 1999 ; no 1256.

The factors influencing the production and deposition of carbonate sediments are known. These are namely accommodation variations (eustasy and tectonics), siliciclastic sediment input, environmental changes (temperature, salinity, trophic level), nature of the producing ecologies, and the hydrodynamic regime. However, the manner in which these factors integrate through time to produce the...

Université de Fribourg

Evidences of winter ascending air circulation throughout talus slopes and rock glaciers situated in the lower belt of alpine discontinuous permafrost (Swiss Alps)

Delaloye, Reynald ; Lambiel, Christophe

In: Norwegian Journal of Geography

The winter ascending circulation of air throughout an accumulation of coarse slope sediments (the so-called chimney effect) facilitates the cooling of the ground and even the occurrence of permafrost in the lower part of a deposit. Simultaneously, any freezing is unlikely to occur in the upper part. The chimney effect has been reported to date mainly for cold and sometimes perennially frozen...