Flutter of Darrieus wind turbine blades: Correlation of theory and experiment

Flutter analysis of two wind turbines was correlated with experimental data for flutter of Darrieus blades

The Effect of Conditional Cash Transfers on Educational Opportunities - Experimental Evidence from Latin America

Conditional Cash Transfers (CCTs) provide income to the poor in an effort to improve current welfare and promote investment in human and social capital to prevent future deprivation. So far, the impact evaluation literature has focused on estimating current effects on outcomes such as school attendance, consumption and labor supply. However, these studies overlook potential redistributive effects, mainly via the equalization of opportunities. The ensuing analysis draws from recent contributions in the literature on opportunities and incorporates these with impact evaluation methods. The main findings indicate a remarkable redistributive effect of CCTs and a positive initial impact on opportunities. However, while mean outcomes improve markedly, the evidence suggests that the distribution of opportunities readjusts to the positive gains, perhaps indicating deeply rooted inequities. These results are expected to encourage discussion on program impact beyond those evaluated and addressing the programs’ long-term consequences.poverty, opportunities, education, children, impact evaluation, conditional cash transfers

Concepts and methods in optimization of integrated LC VCOs

Underlying physical mechanisms controlling the noise properties of oscillators are studied. This treatment shows the importance of inductance selection for oscillator noise optimization. A design strategy centered around an inductance selection scheme is executed using a practical graphical optimization method to optimize phase noise subject to design constraints such as power dissipation, tank amplitude, tuning range, startup condition, and diameters of spiral inductors. The optimization technique is demonstrated through a design example, leading to a 2.4-GHz fully integrated, LC voltage-controlled oscillator (VCO) implemented using 0.35-μm MOS transistors. The measured phase-noise values are -121, -117, and -115 dBc/Hz at 600-kHz offset from 1.91, 2.03, and 2.60-GHz carriers, respectively. The VCO dissipates 4 mA from a 2.5-V supply voltage. The inversion mode MOSCAP tuning is used to achieve 26% of tuning range. Two figures of merit for performance comparison of various oscillators are introduced and used to compare this work to previously reported results