MDGs and Microcredit: An Empirical Evaluation for Latin American Countries

This study uses for the first time household survey data from a number of Latin American countries to investigate the degree and effects of the access to credit on the income and education of poor households. With this goal in mind, multivariate regressions are run to estimate the impact of the credit to the poor on their labor income and on the probability of their children to stay at both primary and secondary school. Afterwards, based on these results, alternative credit policies are simulated. Much in line with the available microcredit evidence, the study provides mixed results: while no negative effects are identified, positive and significant loadings are found in several, but not all cases. The simulation exercises support the claim that microcredit might be a relatively powerful but still limited tool for meeting the MDGs.

Fault-tolerant control under controller-driven sampling using virtual actuator strategy

We present a new output feedback fault tolerant control strategy for continuous-time linear systems. The strategy combines a digital nominal controller under controller-driven (varying) sampling with virtual-actuator (VA)-based controller reconfiguration to compensate for actuator faults. In the proposed scheme, the controller controls both the plant and the sampling period, and performs controller reconfiguration by engaging in the loop the VA adapted to the diagnosed fault. The VA also operates under controller-driven sampling. Two independent objectives are considered: (a) closed-loop stability with setpoint tracking and (b) controller reconfiguration under faults. Our main contribution is to extend an existing VA-based controller reconfiguration strategy to systems under controller-driven sampling in such a way that if objective (a) is possible under controller-driven sampling (without VA) and objective (b) is possible under uniform sampling (without controller-driven sampling), then closed-loop stability and setpoint tracking will be preserved under both healthy and faulty operation for all possible sampling rate evolutions that may be selected by the controller

Labor Informality Effects of a Poverty-Alleviation Program

In the midst of a serious macroeconomic crisis Argentina implemented a large social program – the Programa Jefes de Hogar (PJH) – that provides cash transfers to unemployed household heads meeting certain criteria. In practice, giving the difficulties in monitoring informal jobs, the unemployment requirement of the PJH would imply a disincentive for the program participants to search for a formal job. By applying matching techniques we evaluate the empirical relevance of this prediction during the period of strong economic growth that followed the crisis. We find some evidence on the informality bias of the PJH when the value of the transfer was relatively high compared to wages in the formal labor market.informality, employment, Argentina, evaluation, program, Jefes

Large-signal stability conditions for semi-quasi-Z-source inverters: switched and averaged models

The recently introduced semi-quasi-Z-source in- verter can be interpreted as a DC-DC converter whose input- output voltage gain may take any value between minus infinity and 1 depending on the applied duty cycle. In order to generate a sinusoidal voltage waveform at the output of this converter, a time-varying duty cycle needs to be applied. Application of a time-varying duty cycle that produces large-signal behavior requires careful consideration of stability issues. This paper provides stability results for both the large-signal averaged and the switched models of the semi-quasi-Z-source inverter operating in continuous conduction mode. We show that if the load is linear and purely resistive then the boundedness and ultimate boundedness of the state trajectories is guaranteed provided some reasonable operation conditions are ensured. These conditions amount to keeping the duty cycle away from the extreme values 0 or 1 (averaged and switched models), and limiting the maximum PWM switching period (switched model). The results obtained can be used to give theoretical justification to the inverter operation strategy recently proposed by Cao et al. in [1].Comment: Submitted to the IEEE Conf. on Decision and Control, Florence, Italy, 201

Beamforming Design for Joint Localization and Data Transmission in Distributed Antenna System

A distributed antenna system is studied whose goal is to provide data communication and positioning functionalities to Mobile Stations (MSs). Each MS receives data from a number of Base Stations (BSs), and uses the received signal not only to extract the information but also to determine its location. This is done based on Time of Arrival (TOA) or Time Difference of Arrival (TDOA) measurements, depending on the assumed synchronization conditions. The problem of minimizing the overall power expenditure of the BSs under data throughput and localization accuracy requirements is formulated with respect to the beamforming vectors used at the BSs. The analysis covers both frequency-flat and frequency-selective channels, and accounts also for robustness constraints in the presence of parameter uncertainty. The proposed algorithmic solutions are based on rank-relaxation and Difference-of-Convex (DC) programming.Comment: 15 pages, 9 figures, and 1 table, accepted in IEEE Transactions on Vehicular Technolog

On the Asymptotic Properties of Euclidean Dial-A-Ride Routing

A conjecture by Stein [1], proposing a probabilistic limit result for the shortest possible route of a bus that has to transfer passengers between random locations in some region of the plane, is refuted.- The existence of such limit result remains an open question