A method is proposed for arbitrarily engineering the high-order harmonic generation phase achieved by shaping a laser pulse and employing xuv light or x rays for ionization. This renders the production of bandwidth-limited attosecond pulses possible while avoiding the use of filters for chirp compensation. By adding the first 8 Fourier components to a sinusoidal field of 1016 W/cm2, the bandwid...

In conventional sliding-mode control systems, the sliding-mode motion is of reduced order. Two main problems hindering the application of the sliding-mode control are the singularity in terminal slidingmode control systems and the chattering in both the conventional linear sliding-mode and the terminal sliding-mode control systems. This paper proposes a chattering-free full-order terminal-slidi...

First-order logic (FOL) is a formal deductive system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first-order predicate calculus (FOPC), the lower predicate calculus, the language of first-order logic or predicate logic. Unlike natural languages such as English, FOL uses a wholly unambiguous formal language interpreted by mathematical str...

Operator Precedence Grammars (OPGs) define a deterministic class of context-free languages, which extend input-driven languages and still enjoy many properties: they are closed w.r.t. Boolean operations, concatenation and Kleene star; the emptiness problem is decidable; they are recognized by a suitable model of pushdown automaton; they can be characterized in terms of a monadic second-order lo...

For every odd positive integer m we prove the existence of a Latin square of order 3m having no proper Latin subsquares. Combining this with previously known results it follows that subsquare-free Latin squares exist for all odd orders. © 2005 Elsevier Ltd. All rights reserved.

Free-word order languages have long posed significant problems for s tandard parsing algorithms. This paper reports on an implemented parser, based on GovernmentBinding theory (GB) (Chomsky, 1981, 1982), for a particular free-word order language, Warlpiri, an aboriginal language of central Australia. The parser is explicitly designed to t ransparent ly mirror the principles of GB. The operation...

In free word order languages, every s('.ni;cn(:(~ is cml)eddcd in its specific contexL The order of consl;ituenLs is d('tcrmincd l)y the categories theme, t heme and contrastive J'oc'us. This paper shows [low to recognisc mid to transhti,e these cat;egorles autom;~t;ically on ;~ serH,e.ntial basis, so that SCilI;ClIC(.' ('ml)edding; can I)c' achieved wit;houL having i;o tel'e,' 1,o l,h(', co,> ...

One protection of cryptographic implementations against sidechannel attacks is the masking of the sensitive variables. In this article, we present a first-order masking that does not leak information when the registers change values according to some specific (and realistic) rules. This countermeasure applies to all devices that leak a function of the distance between consecutive values of inte...