Tracking a cold filament with matched-field inversion

Rep 01/02 - SiPLAB 09/July/2002Simulation tests are carried out to estimate the time, range and depth variations of ocean acoustic properties. The estimation is based on matched- eld inversion de ned by a coupled mode acoustic model, a linear mis t function and an hybrid search algorithm. It is shown that tracking cold laments is possible even in non-optimal conditions

Estimation of the properties of a range-dependent ocean environment. A simulation study

Rep 03/01 - SiPLAB 26/October/2001This report describes a simulation study to estimate the range and depth variations of ocean acoustic properties. The estimation is based on matched- eld inversion. Results show the feasibility of detecting the presence of an abnormaltemperature water entity

Reconciling the Old Theory and the New Evidence: Comments on Ronald Mann\u27s \u27The Role of Letters of Credit in Payment Transactions\u27

Ronald Mann\u27s thorough research and rigorous analysis provide compelling evidence that the commercial letter of credit does not further the fundamental purpose traditionally associated with it. Equally persuasive are his hypotheses about the functions that letters of credit actually serve in the real world. The objective statistics are startling. An overwhelming majority of letter of credit seller-beneficiaries make at least initial presentations to issuing or correspondent banks that by the express terms of the letter of credit do not entitle the seller to payment. Without a waiver from its customer, the issuing bank is legally entitled to, and surely will demand, strict compliance with these terms. It is only the voluntary foregoing by the buyer-applicant of its own unambiguous formal power, which is essentially always forthcoming, that enables the seller to draw on the letter of credit. Thus, the normal course of a letter-of-credit transaction at least initially places the seller at the mercy of the buyer. Given these empirical findings, it is difficult to believe that the persistent use of letters of credit in commercial transactions has anything to do with their theoretical potential to ensure that the seller actually gets paid. It is difficult to believe, but not impossible. Mann recognizes that his evidence does not conclusively refute the traditional view that the principal function of the letter of credit is to assure payment. At least one plausible conceptual account of the letter of credit remains that is consistent both with the new, surprising empirics and the old idea that the commercial letter of credit is primarily an atomic element of the payment system. The traditional view does not depend on the legal enforceability of letters of credit because one does not need legal rights to feel assured of payment

Economie van energiegewassen

Bio-energie staat sterk in de belangstelling. De wens naar een meer duurzame energievoorziening is hierbij een belangrijke drijfveer. Ook vanuit de akkerbouw is er interesse in het telen van gewassen voor de productie van energie. Belangrijke vraag bij de afweging om energiegewassen te gaan telen, is het economisch perspectief. In dit onderzoek zijn de saldi voor gewassen met als teelt doel covergisting, biodiesel en bio-ethanol beoordeeld. Hierbij zijn teelttechnische en milieuaspecten meegenomen. Aanvullend is ook gekeken of, en zo ja, welke akkerbouwreststromen ingezet kunnen worden voor covergisting. Tevens is onderzocht of akkerbouwers zelf in hun eigen brandstof kunnen voorzien door de teelt en verwerking van koolzaad tot koolzaadolie

Stock index returns’ density prediction using GARCH models: Frequentist or Bayesian estimation?

Using well-known GARCH models for density prediction of daily S&P 500 and Nikkei 225 index returns, a comparison is provided between frequentist and Bayesian estimation. No significant difference is found between the qualities of the forecasts of the whole density, whereas the Bayesian approach exhibits significantly better left-tail forecast accuracy

Milieuspagaat bij beweiding: broeikasgassen of MINAS

Beweiding heeft invloed op de mate en de vorm waarin stikstof verloren gaat. Het volledig opstallen van de koeien is in veel gevallen een effectieve maatregel voor het halen van de Minas-normen

Stock index returns’ density prediction using GARCH models: Frequentist or Bayesian estimation?

Using well-known GARCH models for density prediction of daily S&P 500 and Nikkei 225 index returns, a comparison is provided between frequentist and Bayesian estimation. No significant difference is found between the qualities of the forecasts of the whole density, whereas the Bayesian approach exhibits significantly better left-tail forecast accuracy

Door wisselbouw blijft bodemvruchtbaarheid op peil

Op De Marke is onderzocht hoe de bodemvruchtbaarheid zich ontwikkelt. Om binnen milieukundige randvoorwaarden te produceren past De Marke een aangepast beheer toe. Dit gebeurt met evenwichtsbemesting voor fosfaat, een stikstofaanvoer naar de bodem die de helft lager is dan gangbaar, een hoog aandeel maïs en wisselbouw