We present a new numerical method for the analysis of second-harmonic generation (SHG) in oneand twodimensional (1D, 2D) diffraction gratings with arbitrary profile made of non-centrosymmetric optical materials. Our method extends the generalized source method (GSM), which is a highly efficient alternative to the conventional Fourier modal method, to quadratically nonlinear diffraction gratings...

130-W average-power picosecond green laser pulses at 514.5 nm are generated from a frequency-doubled hybrid cryogenic Yb:YAG laser. A second-harmonic conversion efficiency of 54% is achieved with a 15-mm-long noncritically phase-matched lithium triborate (LBO) crystal from a 240-W 8-ps 78-MHz pulse train at 1029 nm. The high-average-power hybrid laser system consists of a picosecond fiber chirp...

A framework for joint source/channel coding of speech is presented. It is based on a harmonic representation of the speech signal and facilitates efficient quantization of harmonic amplitudes and phases both in a single description and a multiple description setting. Furthermore, it combines high-quality packet loss concealment with efficient source coding and multiple description coding. Two p...

In this paper, computer simulation of a three-phase synchronous motor drive is described. This drive/system is supplied with a new type of pulse-width modulated voltage source inverter (PWM VSI) whose amplitude of the first harmonic, compared to a conventional sinusoidal PWM VSI, is increased by about 17% and whose amplitude of higher harmonics is also reduced inversely proportional to their or...

A compact and stable method for generating high-intensity linearly polarized continuum mid-IR and terahertz light using ultrafast femtosecond (fs) laser pulses is demonstrated. Continuous light generation from <400 cm(-1) (12 THz, 25 microm) to >3300 cm(-1) (100 THz, 3 microm) in a sub-100 fs laser pulse is facilitated by nonlinear mixing of the fundamental, second harmonic, and third harmonic ...

Melody is the pitch perceived from the most dominant source in the polyphonic music. This paper describes our algorithm for melody extraction submitted for the audio melody extraction task of the Music Information Retrieval Evaluation eXchange (MIREX) 2012. The task consists of two parts: melody estimation and voicing detection. The presented algorithm performs the melody estimation in an onlin...

1.1 HARMONICS IN ELECTRICAL SYSTEMS ............................................................................................ 1 1.2 CONVENTIONAL TWO-LEVEL AND THREE-LEVEL VOLTAGE SOURCE INVERTER ............................... 2 1.3 MULTILEVEL VOLTAGE SOURCE INVERTER..................................................................................... 5 1.3.1 Diode-Clamped Multilevel Inverter...

We develop a green light source with low spatial coherence via intracavity frequency doubling of a solid-state degenerate laser. The second-harmonic emission supports many more transverse modes than the fundamental emission, and exhibits lower spatial coherence. A strong suppression of speckle formation is demonstrated for both fundamental and second-harmonic beams. Using the green emission for...

This paper presents a novel three-phase power factor corrector (PFC) circuit which uses two power switches working in zero-voltage-switching (ZVS) condition. The two switches along with a high-frequency inductor constitute a high-frequency current source which is responsible for the energy transfer in the circuit. The input current is partly continuous and partly discontinuous. The total harmon...

A combination of rectifier and DC – DC chopper is useful in feeding DC loads where the DC input to the loads needs to be stepped up or down. Both rectifier and chopper are based on power electronic switches which inject harmonics in the system. This harmonics is an undesirable effect which should be mitigated effectively. For this, passive harmonic filters are used. Passive harmonic filters are...