Possible evidence for "dark radiation" from Big Bang Nucleosynthesis Data

We address the emerging discrepancy between the Big Bang Nucleosynthesis data and standard cosmology, which asks for a bit longer evolution time. If this effect is real, one possible implication (in a framework of brane cosmology model) is that there is a ``dark radiation'' component which is negative and makes few percents of ordinary matter density. If so, all scales of this model can be fixed, provided brane-to-bulk leakage problem is solved.Comment: We found that references to some nhumbers from unpublished ref.3 in v1 lead to confusion of some readers: we decided to removed those in v

Business Cycles in Emerging market Economies: A New View of the Stylised Facts

This paper builds on an earlier work in business cycle theory - explicitly in the classical cycle tradition of Burns and Mitchell (1946) and the more recent work by Harding and Pagan (e.g.: 2002a; 2005b; 2005a) - to identify and analyse business cycles in emerging market economies. The goal is to revisit the work of for example Agénor, McDermott and Prasad (2000), whom have established a set of stylised facts for business cycle fluctuations in developing countries. Agénor, et. al. (2000) established these stylised facts using the presently standard method of analysing the features of serially correlated deviations from trends (idenified with statistical techniques such as the Hodrick-Prescott filter) in certain macroeconomic time series, including real GDP, the price level, and components of final demand. The alternative method, implemented in this paper, uses an algorithm of Bry and Boschan (1971), and the recent work of Harding and Pagan to identify the various stylised facts regarding the duration, steepness, amplitude and concordance of these fluctuations in emerging market economies.business cycles, turning points, emerging market economies, quantitative analysis of business cycles, time series econometrics, regression with binary variables

The illusive quest: do international capital controls contribute to currency stability?

We investigate the effectiveness of capital controls in insulating economies from currency crises, focusing in particular on both direct and indirect effects of capital controls and how these relationships may have changed over time in response to global financial liberalization and the greater mobility of international capital. We predict the likelihood of currency crises using standard macroeconomic variables and a probit equation estimation methodology with random effects. We employ a comprehensive panel data set comprised of 69 emerging market and developing economies over 1975–2004. Both standard and duration-adjusted measures of capital control intensity (allowing controls to "depreciate" over time) suggest that capital controls have not effectively insulated economies from currency crises at any time during our sample period. Maintaining real GDP growth and limiting real overvaluation are critical factors preventing currency crises, not capital controls. However, the presence of capital controls greatly increases the sensitivity of currency crises to changes in real GDP growth and real exchange rate overvaluation, making countries more vulnerable to changes in fundamentals. Our model suggests that emerging markets weathered the 2007-08 crisis relatively well because of strong output growth and exchange rate flexibility that limited overvaluation of their currencies.Financial crises ; Capital market ; Emerging markets ; Econometric models ; Panel analysis

From Java to real-time Java : A model-driven methodology with automated toolchain

Real-time systems are receiving increasing attention with the emerging application scenarios that are safety-critical, complex in functionality, high on timing-related performance requirements, and cost-sensitive, such as autonomous vehicles. Development of real-time systems is error-prone and highly dependent on the sophisticated domain expertise, making it a costly process. There is a trend of the existing software without the real-time notion being re-developed to realise real-time features, e.g., in the big data technology. This paper utilises the principles of model-driven engineering (MDE) and proposes the first methodology that automatically converts standard time-sharing Java applications to real-time Java applications. It opens up a new research direction on development automation of real-time programming languages and inspires many research questions that can be jointly investigated by the embedded systems, programming languages as well as MDE communities

Best Effort MPI/RT as an Alternative to MPI: Design and Performance Comparison

The Real-Time Message Passing Interface (MPI/RT) is an emerging real-time communications middleware standard for distributed real-time applications. The Message Passing Interface (MPI) is the de facto standard for high performance parallel application development. In this thesis, we describe how MPI/RT with best effort quality of service can be used as an alternative for MPI. Mercury Computer Systems\u27 RACE embedded parallel computer is used as the platform for comparison of design and performance of these two standards. The main advantages MPI/RT has over MPI are its explicit support for communication channels and its emphasis on early binding. Design and implementation of best effort MPI/RT on Mercury is described and its performance is compared with MPI in order to illustrate how MPI/RT features allow implementations to exploit the underlying platform more optimally. The results for the benchmarks show that MPI/RT outperforms MPI in almost all cases examined

Real-time modelling of DDS for event-driven applications

REACTION 2012. 1st International workshop on Real-time and distributed computing in emerging applications. December 4th, 2012, San Juan, Puerto Rico.The Data Distribution Service (DDS) standard defines a data-centric distribution middleware that supports the development of distributed real-time systems. To this end, the standard includes a wide set of configurable parameters to provide different degrees of Quality of Service (QoS). This paper presents an analysis of these QoS parameters when DDS is used to build reactive applications normally designed under an event-driven paradigm, and shows how to configure DDS to obtain predictable applications suitable to apply traditional schedulability analysis techniques.This work has been funded in part by the Spanish Government under grant number TIN2011-28567-C03-02 (HI-PARTES)

Run-time Support for Real-Time Multimedia in the Cloud

REACTION 2013. 2nd International Workshop on Real-time and distributed computing in emerging applications. December 3rd, 2013, Vancouver, Canada.This paper summarizes key research findings in the area of real-time performance and predictabil- ity of multimedia applications in cloud infrastruc- tures, namely: outcomes of the IRMOS European Project, addressing predictability of standard vir- tualized infrastructures; Osprey, an Operating Sys- tem with a novel design suitable for a multitude of heterogeneous workloads including real-time soft- ware; MediaCloud, a novel run-time architecture for offering on-demand multimedia processing facil- ities with unprecedented dynamism and flexibility in resource management. The paper highlights key research challenges ad- dressed by these projects and shortly presents ad- ditional questions lying ahead in this area

Aid, growth, and real exchange rate dynamics

Devarajan, Go, Page, Robinson, and Thierfelder argued that if aid is about the future and recipients are able to plan consumption and investment decisions optimally over time, then the potential problem of an aid-induced appreciation of the real exchange rate (Dutch disease) does not occur. In their paper,"Aid, Growth and Real Exchange Rate Dynamics,"this key result is derived without requiring extreme assumptions or additional productivity story. The economic framework is a standard neoclassical growth model, based on the familiar Salter-Swan characterization of an open economy, with full dynamic savings and investment decisions. It does require that the model is fully dynamic in both savings and investment decisions. An important assumption is that aid should be predictable for intertemporal smoothing to take place. If aid volatility forces recipients to be constrained and myopic, Dutch disease problems become an issue.Economic Theory&Research,Debt Markets,Currencies and Exchange Rates,Emerging Markets,