The impact of sudden stops in capital flows on output and investment: Selected emerging markets

Abstract. We evaluate how vulnerable the emerging markets are to sudden stops, that is, capital inflow reversals, using panel data for 12 emerging economies for the period 1976-2002 that experienced such reversals. We investigate the impact of sudden stops on the macroeconomic indicators of economic growth and investment by employing the Generalized Method of Moments (GMM) estimation methodology. A robustness check is performed using regional groups and introducing additional control variables. We find that sudden stops have lagging, negative, and robust effect on output and investment, while the effect on investment is not always robusth.Keywords. Sudden stops, Economic growth, Capital flows, Emerging markets, GMM.JEL. E40, F32, F36, G15

Reliability assesment of distribution systems with distributed generation based on Bayesian networks

Reliability assessment is of primary importance in designing and planning distribution systems that operate in an economical manner with minimal interruption of customer loads. Distributed generation (DG) units are subject to failures as all other generation units, the random behavior of these units must be taken into account in the analysis. In this paper, a new method based on Bayesian Networks is introduced for reliability analysis of distribution systems with distributed generation. The method permits not only computing the reliability indices of a distribution system but also presenting the effect of each component or some components on the system reliability. Thus the shortcomings of traditional reliability assessment methods are overcome. The impacts of DG units, their location, DG unit capacity in each location and their availability, on distribution system reliability are investigated using a study case of distribution including distributed generation

Surface analytical investigation on organometal triiodide perovskite

In a little over a year, there has been an unexpected breakthrough and rapid evolution of highly efficient solid-state hybrid solar cells based on organometal trihalide perovskite materials. This technology has the potential to produce solar cells with the very highest efficiencies while retaining the very lowest cost. The authors have measured the electronic density of states of CH3NH3PbI3 using ultraviolet photoemission spectroscopy (UPS), inverse photoemission spectroscopy (IPES), and x-ray photoemission spectroscopy (XPS). The valence band maximum and conduction band minimum positions are obtained from the UPS and IPES spectra, respectively, by linear extrapolation of the leading edges. The authors investigate the Au/perovskite and C60/perovskite interfaces by UPS and XPS. An interface dipole of 0.1 eV is observed at Au/perovskite interface. The energy levels of perovskite shift upward by ca.0.4 eV with Au coverage of 64Å upon it, resulting in band bending, hence a built-in field in perovskite that encourages hole transport to the interface. The XPS results show a strong initial shift of core levels to lower binding energy in the perovskite, which indicates that electrons transfer from the perovskite film to fullerene molecules. Further deposition of fullerene forms C60 solid, accompanied by the reduction of the electron transfer. The strongest electron transfer happened at 1/4 monolayer of fullerene