For focused pulses of light in isotropic nonlinear media, third-harmonic generation can be strongly affected by group-velocity mismatch between the fundamental and third-harmonic. There is a characteristic time determined by the group-velocity mismatch and the Rayleigh range of the focused pulse. The dynamics depend on two dimensionless quantities, namely the ratio of the characteristic time to...

We efficiently extract an ultraviolet femtosecond pulse train of milliwatt average power and 100 MHz repetition rate from a colliding pulse mode-locked dye laser by intracavity frequency doubling in KDP. The ultraviolet and visible outputs, which are comparable in power and pulse duration, are perfect synchronized with each

We consider an interpretation of monadic second-order logic of order in the continuous time structure of nitely variable signals and show the decidability of monadic logic in this structure. The expressive power of monadic logic is illustrated by providing a straightforward meaning preserving translation into monadic logic of three typical continuous time speciication formalism: Temporal Logic ...

The challenge in visualizing fast microscale fluid motion phenomena is to record high-quality images free of motion-blur. Here, we present an illumination technique based on laser-induced fluorescence which delivers high-intensity light pulses of 7 ns. The light source consists of a Q-switched Nd:YAG laser and a laser dye solution incorporated into a total internal reflection lens, resulting in...

This paper introduces and discusses the main aspects of multicolored femtosecond pulse generation using cascaded four-wave mixing (CFWM) in transparent bulk materials. Theoretical analysis and semi-quantitative calculations, based on the phase-matching condition of the four-wave mixing process, explain the phenomena well. Experimental studies, based on our experiments, have shown the main chara...

Based on the free precession model of the isolated pulsar PSR B1828-11, Link & Epstein (2001) showed that the observed pulse durations require the radio beam to have a non-standard shape: the beam duration is larger for beam sweeps farthest from the dipole axis. In their analysis they assumed that the actual precession period is ≃ 500 d. Recent theoretical studies suggested that the actual prec...

Duration Calculus with Iteration (DC∗) has been used as an interface between original Duration Calculus and Timed Automata, but has not been studied rigorously. In this paper, we study a subset of DC∗ formulas consisting of so-called simple ones which corresponds precisely with the class of Timed Automata. We give a complete proof system and the decidability results for the subset.

Laser milling provides a new method of producing components for the micro tool manufacturing industry. This paper considers the technical capabilities of laser milling when applied to the machining of components for micro tooling. Characteristics important for laser milling as a micro tooling manufacturing process are reviewed. These characteristics are surface finish, aspect ratio, dimensional...

We prove that the particularly narrow subset of the duration calculus which is defined by the BNF φ ::= ⊥ | dSe | A | φ ⇒ φ | (φ; φ) is not recursively axiomatisable or, in other words, incomplete.

BPM maturity is a measure to evaluate how professionally an organization manages its business processes. Previous research provides evidence that higher BPM maturity leads to better performance of processes and of the organization as a whole. It also claims that different organizations should strive for different levels of maturity, depending on their properties. This paper presents an empirica...