The Self-insurance Role of International Reserves and the 2008-2010 Crisis

There is no standard rule for the definition of an “optimal level” of international reserves and several assumptions underlie the rationale behind holding reserves. There are various theoretical approaches, but no standard for the evaluation of the performance of “optimal level” models, and their parameters are difficult to estimate. The literature suggests that the benefits of holding reserves are high, but the accumulation of reserves is a costly strategy. In fact, in a world of high liquidity and free capital flow, establishing an adequate level of international reserves is still a puzzle. The strategy of accumulating international reserves is evaluated here using data from the 2008-2010 crisis and it is shown that countries with higher international reserve levels had less adjustment costs between 2008 and 2010. The cost-benefit relationship of holding reserves in the 2008-2010 crisis is also discussed based on a sample with 71 countries.

Evolving Material Porosity on an Additive Manufacturing Simulation with the Generalized Method of Cells

The effect of material porosity on final part distortion and residual stresses in a selective laser sintering manufacturing simulation is presented here. A time-dependent thermomechanical model is used with the open-source FEA software CalculiX. Effective homogenized material properties for Inconel 625 are precomputed using NASAs Micromechanics Analysis Code with Generalized Method of Cells (MAC/GMC). The evolving porosity of the material is estimated with each pass of the laser beam during simulation runtime. A comparison with a homogenous model and the evolving model shows that the evolving porous model predicts larger distortions with greater residual stresses

An analytical solution for the analysis of zero-length-column experiments with heat effects

An analytical solution for the analysis of zero-length-column (ZLC) experiments with heat effects is developed. The model is an extension of the original one developed by Eic and Ruthven with the inclusion of the energy balance. Two additional parameters are obtained, beta = (DeltaH/C-p) (partial derivativeq/partial derivativeT)\ (c0),(T0) and alpha = (ha/C-p)(r(c)(2)/D-c). A criterion for negligible heat effects, 3L beta/alpha < 0.1, is derived from the analytical solution based on ZLC operating parameters. ZLC desorption curves in nonisothermal operation are discussed. The model reduces to the original solution of isothermal operation developed by Eic and Ruthven when heat effects are negligible. ZLC experiments with heat effects are analyzed, and trends are in good agreement with theory. Because of its simplicity, the model is a valuable tool for the analysis of ZLC experiments with heat effects

Duration of Low Wage Employment: A Study Based on a Survival Model

This paper includes a survival analysis which attempts to explain the duration, as in the number of years a worker remains in a low wage situation. Explanatory variables take into account the characteristics of the employee, such as education, age, tenure with the company, gender and nationality, and the characteristics of the job and the company such as industry affiliation, number of employees, age of the company and location.low wage, survival, Portugal

Brazilian Strategy for Managing the Risk of Foreign Exchange Rate Exposure During a Crisis

Even in a floating foreign exchange rate regime, monetary authorities sometimes intervene in the currency market due to liquidity demand and foreign exchange crises. Typically, central banks intervene using foreign currency trades and/or by changing domestic interest rates. We discuss this framework in the context of an optimal impulse stochastic control model. The control and performance equations include interventions with swap operations in the domestic market, since the Central Bank of Brazil also uses these operations. We evaluate risk management strategies for central bank interventions in case of crisis based on the model. We conclude that the Brazilian risk management strategy of increasing holdings of international reserves and decreasing short foreign exchange rate exposure in domestic public debt after 2004 gave the country more flexibility to manage foreign exchange rate risk in 2008 and to avoid higher interest rates to attract international capital as was necessary in previous crises.

Can the distributional impacts of macroeconomic shocks be predicted? A comparison of the performance of macro-micro models with historical data for Brazil

What was the impact of Brazil's 1998-99 currency crisis-which resulted in a change of exchange rate regime and a large real devaluation-on the occupational structure of the labor force and the distribution of incomes? Would it have been possible to predict such effects ahead of the crisis? The authors present an integrated macro-micro model of the Brazilian economy in 1998. The model consists of an applied general equilibrium macroeconometric component, connected through a set of linkage aggregate variables to a microeconomic model of household incomes. The authors use this framework to predict the employment and distributional consequences of the 1999 Brazilian currency crisis, based on 1998 household survey data. They then test the predictive performance of the model by comparing its simulated results with the actual household survey data observed in 1999. In addition to the fully integrated macro-micro model, the authors also test the performances of the microeconometric model on its own, and of a"representative household groups"approach. They find that the integrated macro-micro econometric model, while still inaccurate on many dimensions, can actually predict the broad pattern of the incidence of changes in household incomes across the distribution reasonably well, and much better than the alternative approaches. The authors conclude that further experimentation with these tools might be of considerable potential usefulness to policymakers.Labor Policies,Payment Systems&Infrastructure,Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Economic Theory&Research,Environmental Economics&Policies,Macroeconomic Management,Inequality,Economic Stabilization

BUSCA, RECUPERAÇÃO E VISUALIZAÇÃO DE RECURSOS ACADÊMICOS DISTRIBUÍDOS

Universities are reference when the subject is research and innovation. So much research creates a lot of related material (papers and videos for example), mostly this material is not shared with the community (of any nature: academic, scientific or public) because there is not a means with easy access and use. Don’t just researches create academic resources, the environment of a university by itself offer a wide range of activities that create academic resources: classes, scientific initiations, symposia, congress and others. The biggest problem of this scenario is that such a wealth of subjects doesn’t have any value when they are saved. As every university has a good IT infrastructure, the hosting and providing of such resources on Internet is trivial, the problem is that should know where the resources are to get them. This work pretends to take place in this context, allow the search of such resources in a transparent way to the final use

Application-level fault tolerance in real-time embedded systems

Critical real-time embedded systems need to make use of fault tolerance techniques to cope with operation time errors, either in hardware or software. Fault tolerance is usually applied by means of redundancy and diversity. Redundant hardware implies the establishment of a distributed system executing a set of fault tolerance strategies by software, and may also employ some form of diversity, by using different variants or versions for the same processing. This work proposes and evaluates a fault tolerance framework for supporting the development of dependable applications. This framework is build upon basic operating system services and middleware communications and brings flexible and transparent support for application threads. A case study involving radar filtering is described and the framework advantages and drawbacks are discussed.Fundação para a Ciência e a Tecnologia (FCT

Middleware Fault Tolerance Support for the BOSS Embedded Operating System

Critical embedded systems need a dependable operating system and application. Despite all efforts to prevent and remove faults in system development, residual software faults usually persist. Therefore, critical systems need some sort of fault tolerance to deal with these faults and also with hardware faults at operation time. This work proposes fault-tolerant support mechanisms for the BOSS embedded operating system, based on the application of proven fault tolerance strategies by middleware control software which transparently delivers the added functionality to the application software. Special attention is taken to complexity control and resource constraints, targeting the needs of the embedded market.Fundação para a Ciência e a Tecnologia (FCT