This paper presents an impedance-matching-based control scheme for the harmonic resonance damping of multiple grid-connected-converters (GCCs) with LCL filters. As indicated in this paper, harmonic resonance occurs if a GCC possesses an output impedance that is not matched with the rest of the network in some specific frequency bands. It is also revealed that the resonance frequency is associat...

In connection with recent theoretical predictions, enhancement of optical second harmonic generation (SHG) by diffractive coupling to the silver surface-plasmon polariton (SPP) mode is shown experimentally to be maximized on a biperiodic corrugated surface. Optimized first-order diffractive coupling of incident radiation to the SPP maximizes resonance enhancement of the surface-localized electr...

This thesis presents a study of resonance dynamics in circuits of superconducting Josephson junctions. The Josephson junction is an intrinsically nonlinear device which, under certain conditions, can exhibit harmonic oscillations. This research begins with the dynamics of Josephson junctions connected in parallel with either periodic (ring geometry) or open-ended (row geometry) boundary conditi...

Nuclear magnetic resonance microscopy poses fundamental as well as practical challenges. The Torrey–Bloch equation obeyed by the magnetization density is basic to this field. We discuss exact solutions of the equation from a generalization that addresses the motion of the nuclear spins towards an attractive center with an arbitrary time dependence in the attractive (harmonic) potential. The sol...

We consider a dilute two-component atomic fermion gas with unequal populations in a harmonic trap potential using the mean field theory and the local density approximation. We show that the system is phase separated into concentric shells with the superfluid in the core surrounded by the normal fermion gas in both the weak-coupling BCS side and near the Feshbach resonance. In the strong-couplin...

Second-harmonic generation (SHG) from periodic arrays of subwavelength rectangular air hole with various aspect ratios perforated in gold thin films can get resonantly enhanced for some specific geometric shapes. Here we clarify the physical origin of this shape resonance effect. A nonlinear coupled-mode theory is set up to solve energy conversion from fundamental wave (FW) mode to second-harmo...

Consider a one-mass system with two degrees of freedom, nonlin-early coupled, with parametric excitation in one direction. Assuming the internal resonance 1:2 and parametric resonance 1:2 we derive conditions for stability of the trivial solution by using both the harmonic balance method and the normal form method of averaging. If the trivial solution becomes unstable a stable periodic solution...

We investigate a method of selectively targeting cancer cells by means of ultrasound harmonic excitation at their resonance frequency, which we refer to as oncotripsy. The geometric model of the cells takes into account the cytoplasm, nucleus and nucleolus, as well as the plasma membrane and nuclear envelope. Material properties are varied within a pathophysiologically-relevant range. A first m...

We report the observation of multiple harmonic generation in electric dipole spin resonance in an InAs nanowire double quantum dot. The harmonics display a remarkable detuning dependence: near the interdot charge transition as many as eight harmonics are observed, while at large detunings we only observe the fundamental spin resonance condition. The detuning dependence indicates that the observ...

LCL filter has the characteristic of prompt attenuation over the high-frequency range, but the thirdorder control system exits the resonance problem. Nonetheless, the inherent non-linear characteristic and dead-time effects of switching tubes, along with the DC-side voltage secondary pulsation and grid harmonic pollution, arouse a wealth of low-order harmonics injected which is tough to be filt...