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.

Among the three major components of a closed birth interval, waiting time to conception can somehow be managed with effective contraceptives while gestation is universally constant in its duration; the duration of postpartum amenorrhoea (PPA) varies in complex nature. The present study aimed to investigate the proximate factors influencing the duration of PPA. A community-based, cross-sectional...

We develop sub-Nyquist sampling systems for signals comprised of several, possibly overlapping, finite duration pulses with unknown shapes and time positions. To the best of our knowledge, stable and low-rate sampling strategies for a superposition of unknown pulses without knowledge of the pulse locations have not been derived. We propose a multichannel scheme based on Gabor frames that exploi...

This work explores the use of statistical techniques, namely stratified sampling and cluster analysis, as powerful tools for deriving traffic properties at the flow level. Our results show that the adequate selection of samples leads to significant improvements allowing further important statistical analysis. Although stratified sampling is a well-known technique, the way we classify the data p...

We present an alternative method for measuring ultrashort extreme-ultraviolet pulses that can be synchronized with an intense infrared pulse. The method, based on photoionization of a target atom by the extremeultraviolet pulse in the presence of the infrared pulse, has a potential accuracy of close to 1 fs and is susceptible to single-shot operation. It is demonstrated on harmonic 15 of a tita...

We present a monolithic passively Q-switched microchip laser generating 200 ps pulses at a wavelength of 1064 nm with a repetition rate of up to 2 MHz. While maintaining transversal and longitudinal single-mode operation, the pulse energy can be changed from 130 nJ to 400 nJ by varying the pump conditions of the laser. To the best of our knowledge, the repetition rate of 2 MHz is by far the hig...

In this paper we show that every real-time system speciied in a certain subset of Duration Calculus 24] can be decomposed into an untimed system communicating with suitable timers. Both asynchronous and synchronous communication are considered.

The spin dynamics in Ni is studied by an exact diagonalization method on the ultrafast time scale. It is shown that the femtosecond relaxation of the magneto-optical response results from exchange interaction and spin-orbit coupling. Each of the two mechanisms affects the relaxation process differently. We find that the intrinsic spin dynamics occurs during about 10 fs while extrinsic effects s...