521 research outputs found
Interpreting the Hours-Technology time-varying relationship
We investigate the time varying relation between hours and technology shocks using a structural business cycle model. We propose an RBC model with a Constant Elasticity of Substitution (CES) production function that allows for capital- and labor-augmenting technology shocks. We estimate the model with Bayesian techniques. In the full sample, we find (i) evidence in favor of a less than unitary elasticity of substitution (rejecting Cobb-Douglas) and (ii) a sizable role for capital augmenting shock for business cycles fluctuations. In rolling sub-samples, we document that the transmission of technology shocks to hours worked has been varying over time. We argue that this change is due to the increase of the elasticity of factor substitution. That is, labor and capital became less complementary throughout the sample inducing a change in the sign and size of the response of hours. We conjecture that this change may have been induced by a change in the skill composition of the labor input.Hours Worked and Business Cycles, Bayesian Methods.
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Seizures of In Transit Generics at the EU Borders: India and Brazil v. the EU
On May 2010 India and Brazil filed a complaint at the WTO claiming that customs rules in the EU, Regulation 1383/2003 in particular, recently allowed customs authorities to detain certain lots of Indian generics in transit to non-EU states. India and Brazil maintain that these measures contradict relevant TRIPS and GATT provisions. The case has spurred a debate because these measures could affect or impede the protection of public health in some countries, namely the African and Latin American states that are usually the final destination of the Indian manufactured generics
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The ECJ Rules on Private Copying Levy
On 21 October 2010 the European Court of Justice (ECJ) gave its decision in Padawan v SGAE, an interesting case regarding the so-called “private copying levy”. The ECJ held that such a levy is in conformity with Directive 2001/79 (on the harmonization of certain aspects of copyright in the information society) when charged on copying devices sold to individuals, as it can reasonably be assumed that those equipments will be used for copying. Yet the levy should not be charged when said devices are sold to companies and professionals
Another One BITes the Dust: The Distance between Luxembourg and the World is Growing after Achmea
The CJEU has become a gatekeeper. Ever since Opinion 1/91, the CJEU has been imposing barriers to the recognition of decisions by foreign jurisdictions. Its recent Achmea decision is the natural consequence of case law so far. This attitude would not be problematic by itself since, through this attitude, the European Union would still be liable at the international plane, even if it did not implement its international obligations (liability- over property rules). This is not the end of the story. The CJEU accepts the, in principle, relevance of decisions by some international jurisdictions. However, the CJEU has repeatedly failed to establish clear criteria to identify ex ante the circumstances under which this will be the case. As things stand, recognition of foreign judgments is more of a line in the sand, than a dictum set in stone. This attitude is hardly reconcilable with the quintessential elements of a Rechtsstaat
Sultans of Swing? The Emerging WTO Case Law on TBT
Following years of silence after EC-Sardines, three cases were adjudicated by Panels under the WTO Agreement on Technical Barriers to Trade (TBT) in 2011: US-Clove Cigarettes, US-Tuna II (Mexico), and US-COOL. These three cases dealt with key provisions of the Agreement, but the Panels adopted irreconcilable approaches. All three decisions were appealed before the Appellate Body (AB), but even the latter failed to apply a coherent methodology to adjudicate similar.
In Section II, we provide a brief account of the facts and the outcomes of the cases, whereas, in Section III we discuss the methodology applied by the WTO judiciary in the three cases
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A fiscal stimulus with deep habits and optimal monetary policy
A New-Keynesian model with deep habits and optimal monetary policy delivers a larger-than-one multiplier and consumption crowding-in. Optimized Taylor-type rules dominate a conventional Taylor rule. Consumption is crowded out if the Taylor rule is sub-optimal or if commitment is absent
Development of gasoline-ethanol blends laminar flame speed correlations at full-load Si engine conditions via 1D simulations
Nowadays, most of the engineering development in the field of Spark-Ignited (SI) Internal Combustion Engines (ICEs) is supported by 3D-CFD simulations relying on flamelet combustion models. Such kind of models require laminar flame speed as an input to be specified by the user. While several laminar flame speed correlations are available in literature, for gasoline and pure ethanol at ambient conditions, there is a lack of correlations describing laminar flame speed of gasoline-ethanol blends, for different ethanol volume content, at conditions deemed to be representative of engine-like conditions. Toluene Reference Fuel surrogates with addition of ethanol (ETRF), suitable for representing gasoline-ethanol blends up to 85% vol. ethanol content are formulated. Thanks to these surrogates, 1D premixed laminar flame speed calculations are performed at selected engine-relevant conditions for a E5, E20 and E85 fuels. As a final outcome, three different laminar flame speed correlations based on the chemistry-based calculations are derived for E5, E20 and E85 gasoline-ethanol fuel blends focusing on typical full-load engine conditions. Such kind of correlations can be easily implemented in any 3D-CFD code to provide a chemistry-grounded estimation of laminar flame speed during combustion calculations. Such correlations are of practical use, since they might help in developing the next generation of bio-fuels powered internal combustion engines
Knock Tendency Prediction in a High Performance Engine Using LES and Tabulated Chemistry
The paper reports the application of a look-up table approach within a LES combustion modelling framework for the
prediction of knock limit in a highly downsized turbocharged DISI engine.
During experimental investigations at the engine test bed, high cycle-to-cycle variability was detected even for
relatively stable peak power / full load operations of the engine, where knock onset severely limited the overall engine
performance.
In order to overcome the excessive computational cost of a direct chemical solution within a LES framework, the use
of look-up tables for auto-ignition modelling perfectly fits with the strict mesh requirements of a LES simulation, with an
acceptable approximation of the actual chemical kinetics.
The model here presented is a totally stand-alone tool for autoignition analysis integrated with look-up table reading
from detailed chemical kinetic schemes for gasoline. The look-up table access is provided by a multi-linear interpolating
routine internally developed at the \u201cGruppo Motori (GruMo)\u201d of the University of Modena and Reggio Emilia. As the
experimental tests were conducted operating the engine at knock-limited spark advance, the tool is at first validated for
three different LES cycles in terms of knock tolerance, i.e. the safety margin to knock occurrence.
As a second stage, the validation of the methodology is performed for discrete spark advance increases in order to
assess the sensitivity of the modelling strategy to variations in engine operations. A detailed analysis of the unburnt gas
physical state is performed which confirms the knock-limited condition suggested by the experimental tests
Single stage reconstruction of complex head and neck defects involving the skin with a single ALT flap: A ten year review
Background: Multicomponent defects of the head and neck involving the cervical skin pose a reconstructive challenge for microsurgeons and usually requires two flaps. However, many patients who undergo such surgical treatment had prior treatment with radiotherapy and the availability of recipient vessels for free flap reconstruction may be limited. The purpose of this study was to review our experience in the reconstruction of these extensive head and neck defects using a single ALT free flap. Methods: A total of 21 patients with complex defects of the head and neck involving multiple anatomical subunits, including the overlying cervical skin, underwent reconstruction with a single ALT flap. The clinical, functional, and aesthetic outcomes of these patients were reviewed. Results: The mean hospital stay was 24 days. There was one total flap loss due to pedicle thrombosis. The patient underwent a further ALT reconstruction with no postoperative complications. Cervical fistulas occurred in three patients, and all fistulas were healed by simple wound packing. Three patients with tracheal defect had a functional tracheostoma with adequate stomal patency. A modified barium swallowing study was performed on each patient, and all of them achieved total oral intake. Among them, two patients tolerated only a pureed diet. Conclusions: Complex neck reconstruction can be accomplished with a single ALT flap with good clinical and functional results, minimal morbidity and quick recovery
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