The optical signals degrade as travel down the optical link due to the optical fiber properties such as chromatic dispersion, polarization mode dispersion, polarization dependent loss, polarization dependent gain and various fiber nonlinear effects, which are considered as limitations in the high-speed, lang-haul fiber communication systems. Where chromatic dispersion causes different wavelengt...

We present an Yb-fiber oscillator with an all-polarization-maintaining cavity with a higher-order-mode fiber for dispersion compensation. The polarization maintaining higher order mode fiber introduces not only negative second order dispersion but also negative third order dispersion in the cavity, in contrast to dispersion compensation schemes used in previous demonstrations of all-polarizatio...

We present a microstructure-based dual-core dispersion-compensating fiber (DCF) design for dispersion compensation in long-haul optical communication links. The design has been conceptualized by combining the all-solid dual-core DCF and dispersion-compensating photonic crystal fiber. The fiber design has been analyzed numerically by using a full vectorial finite difference time domain method. W...

In this paper, we provide a blow-up mechanism to the modified Camassa-Holm equation with varying linear dispersion. We first consider the case when linear dispersion is absent and derive a finite-time blow-up result with an initial data having a region of mild oscillation. A key feature of the analysis is the development of the Burgers-type inequalities with focusing property on characteristics...

The possibility of controlling the spectral position of the zero group-velocity dispersion point of a negative-index material can be exploited by varying the ratio between the electric and the magnetic plasma frequency to obtain dispersion-free propagation in spectral regions otherwise inaccessible using conventional positive-index materials. Our predictions are confirmed by pulse propagation s...

Non-negativity matrix factorization (NMF) and its variants have been explored in the last decade and are still attractive due to its ability of extracting non-negative basis images. However, most existing NMF based methods are not ready for encoding higher-order data information. One reason is that they do not directly/explicitly model structured data information during learning, and therefore ...

how to cite this article: movahedian ah, heidarzadeh arani m, motaharizad m, mousavi gha, mosayebi z. evaluation of qt dispersion in children with breath holding spells. iran j child neurol. winter 2016; 10(1):25-30. abstract objective breath holding spells (bhs) are common involuntary reflexes in infancy and early childhood. differential diagnosis should embrace long qt syndrome (lqts) and par...

Spectra of phonons with out-of-plane polarization were studied experimentally in a 2D plasma crystal. The dispersion relation was directly measured for the first time using a novel method of particle imaging. The out-of-plane mode was proven to have negative optical dispersion at small wave numbers, comparison with theory showed good agreement. The effect of the plasma wakes on the dispersion r...