Ricardo Madeira

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Quadrature oscillators obtained by superharmonic coupling are known for its good phase noise performance. By making use of the presence of a second harmonic in the common-mode node of an Class D LC oscillator it is possible to design a 2.4 GHz quadrature oscillator using an inverting on-chip transformer. Simulation results in a circuit prototype in 130 nm(More)
We investigate the extent to which racial discrimination, in the form of the biased assessment of students, is prevalent within Brazilian schools. Robust evidence is drawn from unique data pertaining to middle-school students and educators. We nd that even after holding constant performance in blindly scored o cial tests of pro ciency, teacher-assigned Math(More)
Switched capacitor (SC) DC-DC converters can be used to convert an input voltage range into a fixed output voltage value. The efficiency of these circuits depends on the ratio between the input and output voltages and on the parasitic capacitances of the circuit. Depending on the type of capacitor and how it is connected, the impact of the parasitic(More)
Sex reassignment surgery (SRS) in transsexuals is not allowed under Portuguese law which means that individuals have turned for aid to other countries to achieve the corresponding bodily 'correction'. Furthermore, those who submitted to SRS abroad suffered a stressful experience involving an unpredictable outcome when they asked for a subsequent change of(More)
Decentralization of the delivery of public services provision is an important governance reform recently witnessed in many developing countries. Public education has been one of the key public services devolved to lower level governments. This paper uses an exclusive and rich longitudinal data on primary schools to evaluate the e¤ects of the(More)
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